[PATCH v15 net-next 10/10] selftests/net: psp: add dev-get, no-nsid, and cleanup tests

[Wei Wang <weibunny.kernel@gmail.com>]

From: Wei Wang <weibunny@fb.com>

Add the following 3 tests:

- _psp_dev_get_check_netkit_psp_assoc: verifies dev-get output in both
  host and guest namespaces, checking assoc-list, by-association flag,
  and nsid values
- _dev_assoc_no_nsid: tests dev-assoc and dev-disassoc without the nsid
  attribute, verifying ifindex lookup in the caller's namespace
- _psp_dev_assoc_cleanup_on_netkit_del: verifies that deleting the
  associated netkit interface properly cleans up the assoc-list, using
  a disposable netkit pair to avoid disturbing the shared environment

Signed-off-by: Wei Wang <weibunny@fb.com>
---
 tools/testing/selftests/drivers/net/psp.py | 146 ++++++++++++++++++++-
 1 file changed, 145 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/drivers/net/psp.py b/tools/testing/selftests/drivers/net/psp.py
index 78682a425886..315648a770d0 100755
--- a/tools/testing/selftests/drivers/net/psp.py
+++ b/tools/testing/selftests/drivers/net/psp.py
@@ -18,7 +18,7 @@ from lib.py import ksft_not_none
 from lib.py import ksft_variants, KsftNamedVariant
 from lib.py import KsftSkipEx, KsftFailEx
 from lib.py import NetDrvEpEnv, NetDrvContEnv
-from lib.py import NlError, PSPFamily
+from lib.py import Netlink, NlError, PSPFamily, RtnlFamily
 from lib.py import NetNSEnter
 from lib.py import bkg, rand_port, wait_port_listen
 from lib.py import ip
@@ -723,6 +723,147 @@ def _dev_change_notify_multi_ns_netkit(cfg):
                 f" in {label} namespace")
 
 
+def _psp_dev_get_check_netkit_psp_assoc(cfg):
+    """ Check psp dev-get output with netkit interface associated with PSP dev """
+    _assoc_nk_guest(cfg)
+
+    # Check 1: In default netns, verify dev-get has correct ifindex and assoc-list
+    dev_info = cfg.pspnl.dev_get({'id': cfg.psp_dev_id})
+    ksft_eq(dev_info['ifindex'], cfg.psp_ifindex)
+    _check_assoc_list(cfg, cfg.psp_dev_id, cfg.nk_guest_ifindex,
+                      cfg.psp_dev_peer_nsid)
+
+    # Check 2: In guest netns, verify dev-get has assoc-list with nk_guest device
+    with NetNSEnter(cfg.netns.name):
+        peer_pspnl = PSPFamily()
+
+        # Dump all devices in the guest namespace
+        peer_devices = peer_pspnl.dev_get({}, dump=True)
+
+        # Find the device with by-association flag
+        peer_dev = None
+        for dev in peer_devices:
+            if dev.get('by-association'):
+                peer_dev = dev
+                break
+
+        ksft_not_none(peer_dev, "No PSP device found with by-association flag in guest netns")
+
+        # Verify assoc-list contains the nk_guest device
+        ksft_true('assoc-list' in peer_dev and len(peer_dev['assoc-list']) > 0,
+                  "Guest device should have assoc-list with local devices")
+
+        # Verify the assoc-list contains nk_guest ifindex with nsid=-1 (same namespace)
+        found = False
+        for assoc in peer_dev['assoc-list']:
+            if assoc['ifindex'] == cfg.nk_guest_ifindex:
+                ksft_eq(assoc['nsid'], -1,
+                        "nsid should be -1 (NETNSA_NSID_NOT_ASSIGNED) for same-namespace device")
+                found = True
+                break
+        ksft_true(found, "nk_guest ifindex not found in assoc-list")
+
+
+def _dev_assoc_no_nsid(cfg):
+    """ Test dev-assoc and dev-disassoc without nsid attribute """
+    _init_psp_dev(cfg, True)
+
+    # Associate without nsid - should look up ifindex in caller's netns
+    cfg.pspnl.dev_assoc({'id': cfg.psp_dev_id,
+                         'ifindex': cfg.nk_host_ifindex})
+    defer(_try_disassoc, cfg,
+          cfg.psp_dev_id, cfg.nk_host_ifindex)
+    defer(delattr, cfg, 'psp_dev_id')
+    defer(delattr, cfg, 'psp_info')
+
+    # Verify assoc-list contains the device (match by ifindex only)
+    _check_assoc_list(cfg, cfg.psp_dev_id, cfg.nk_host_ifindex)
+
+    # Disassociate without nsid - should also use caller's netns
+    cfg.pspnl.dev_disassoc({'id': cfg.psp_dev_id,
+                            'ifindex': cfg.nk_host_ifindex})
+
+    # Verify assoc-list no longer contains the device
+    dev_info = cfg.pspnl.dev_get({'id': cfg.psp_dev_id})
+    found = False
+    if 'assoc-list' in dev_info:
+        for assoc in dev_info['assoc-list']:
+            if assoc['ifindex'] == cfg.nk_host_ifindex:
+                found = True
+                break
+    ksft_true(not found, "Device should not be in assoc-list after disassociation")
+
+
+def _psp_dev_assoc_cleanup_on_netkit_del(cfg):
+    """Test that assoc-list is cleared when associated netkit is deleted.
+
+    Creates a disposable netkit pair for this test to avoid destroying
+    the shared environment.
+    """
+    _init_psp_dev(cfg, True)
+    defer(delattr, cfg, 'psp_dev_id')
+    defer(delattr, cfg, 'psp_info')
+
+    existing = {cfg.nk_host_ifindex, cfg.nk_guest_ifindex}
+
+    # Create a temporary netkit pair
+    tmp_host_name = "tmp_nk_host"
+    tmp_guest_name = "tmp_nk_guest"
+    rtnl = RtnlFamily()
+    rtnl.newlink(
+        {
+            "ifname": tmp_host_name,
+            "linkinfo": {
+                "kind": "netkit",
+                "data": {
+                    "mode": "l2",
+                    "policy": "forward",
+                    "peer-policy": "forward",
+                },
+            },
+        },
+        flags=[Netlink.NLM_F_CREATE, Netlink.NLM_F_EXCL],
+    )
+    cleanup_netkit = defer(ip, f"link del {tmp_host_name}")
+
+    # Find the peer by diffing against existing netkit ifindexes
+    all_links = ip("-d link show", json=True)
+    tmp_peer = [link for link in all_links
+                if link.get('linkinfo', {}).get('info_kind') == 'netkit'
+                and link['ifindex'] not in existing
+                and link['ifname'] != tmp_host_name]
+    ksft_eq(len(tmp_peer), 1,
+            "Failed to find temporary netkit peer")
+    guest_name = tmp_peer[0]['ifname']
+
+    # Rename and move guest end into the test namespace
+    ip(f"link set dev {guest_name} name {tmp_guest_name}")
+    ip(f"link set dev {tmp_guest_name} netns {cfg.netns.name}")
+    tmp_guest_dev = ip(f"link show dev {tmp_guest_name}",
+                       json=True, ns=cfg.netns)[0]
+    tmp_guest_ifindex = tmp_guest_dev['ifindex']
+    ip(f"link set dev {tmp_guest_name} up", ns=cfg.netns)
+
+    # Associate PSP device with the temporary guest interface
+    cfg.pspnl.dev_assoc({'id': cfg.psp_dev_id,
+                         'ifindex': tmp_guest_ifindex,
+                         'nsid': cfg.psp_dev_peer_nsid})
+
+    # Verify assoc-list contains the temporary device
+    _check_assoc_list(cfg, cfg.psp_dev_id, tmp_guest_ifindex,
+                      cfg.psp_dev_peer_nsid)
+
+    # Delete the temporary netkit pair (deleting one end removes both)
+    ip(f"link del {tmp_host_name}")
+    cleanup_netkit.cancel()
+
+    # Verify assoc-list is cleared after netkit deletion
+    dev_info = cfg.pspnl.dev_get({'id': cfg.psp_dev_id})
+    ksft_true('assoc-list' not in dev_info
+              or len(dev_info['assoc-list']) == 0,
+              "assoc-list should be empty after netkit deletion")
+
+
 def _try_disassoc(cfg, psp_dev_id, ifindex, nsid=None):
     """Best-effort disassociate, ignoring errors if already removed."""
     try:
@@ -840,6 +981,9 @@ def main() -> None:
                         data_basic_send_netkit_psp_assoc,
                         _key_rotation_notify_multi_ns_netkit,
                         _dev_change_notify_multi_ns_netkit,
+                        _psp_dev_get_check_netkit_psp_assoc,
+                        _dev_assoc_no_nsid,
+                        _psp_dev_assoc_cleanup_on_netkit_del,
                     ]
 
                 ksft_run(cases=cases, globs=globals(),
-- 
2.52.0