Commit 4f280376 authored by Yuyang Huang's avatar Yuyang Huang Committed by Paolo Abeni
Browse files

selftests/net: Add selftest for IPv4 RTM_GETMULTICAST support 



This change introduces a new selftest case to verify the functionality
of dumping IPv4 multicast addresses using the RTM_GETMULTICAST netlink
message. The test utilizes the ynl library to interact with the
netlink interface and validate that the kernel correctly reports the
joined IPv4 multicast addresses.

To run the test, execute the following command:

$ vng -v --user root --cpus 16 -- \
    make -C tools/testing/selftests TARGETS=net \
    TEST_PROGS=rtnetlink.py TEST_GEN_PROGS="" run_tests

Cc: Maciej Żenczykowski <maze@google.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: default avatarYuyang Huang <yuyanghuang@google.com>
Link: https://patch.msgid.link/20250207110836.2407224-2-yuyanghuang@google.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent eb4e17a1

Documentation/netlink/specs/rt_addr.yaml

+23 −0
Original line number Diff line number Diff line
@@ -168,6 +168,29 @@ operations: 
        reply:

          value: 20

          attributes: *ifaddr-all

    -

      name: getmaddrs

      doc: Get / dump IPv4/IPv6 multicast addresses.

      attribute-set: addr-attrs

      fixed-header: ifaddrmsg

      do:

        request:

          value: 58

          attributes:

            - ifa-family

            - ifa-index

        reply:

          value: 58

          attributes: &mcaddr-attrs

            - ifa-multicast

            - ifa-cacheinfo

      dump:

        request:

          value: 58

            - ifa-family

        reply:

          value: 58

          attributes: *mcaddr-attrs



mcast-groups:

  list:

tools/testing/selftests/net/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ TEST_PROGS += cmsg_so_priority.sh 
TEST_PROGS += cmsg_time.sh cmsg_ipv6.sh

TEST_PROGS += netns-name.sh

TEST_PROGS += nl_netdev.py

TEST_PROGS += rtnetlink.py

TEST_PROGS += srv6_end_dt46_l3vpn_test.sh

TEST_PROGS += srv6_end_dt4_l3vpn_test.sh

TEST_PROGS += srv6_end_dt6_l3vpn_test.sh

tools/testing/selftests/net/lib/py/__init__.py

+1 −1
Original line number Diff line number Diff line
@@ -5,5 +5,5 @@ from .ksft import * 
from .netns import NetNS

from .nsim import *

from .utils import *

from .ynl import NlError, YnlFamily, EthtoolFamily, NetdevFamily, RtnlFamily

from .ynl import NlError, YnlFamily, EthtoolFamily, NetdevFamily, RtnlFamily, RtnlAddrFamily

from .ynl import NetshaperFamily

tools/testing/selftests/net/lib/py/ynl.py

+4 −0
Original line number Diff line number Diff line
@@ -42,6 +42,10 @@ class RtnlFamily(YnlFamily): 
        super().__init__((SPEC_PATH / Path('rt_link.yaml')).as_posix(),

                         schema='', recv_size=recv_size)



class RtnlAddrFamily(YnlFamily):

    def __init__(self, recv_size=0):

        super().__init__((SPEC_PATH / Path('rt_addr.yaml')).as_posix(),

                         schema='', recv_size=recv_size)



class NetdevFamily(YnlFamily):

    def __init__(self, recv_size=0):

tools/testing/selftests/net/rtnetlink.py

0 → 100755
+30 −0
Original line number Diff line number Diff line 
#!/usr/bin/env python3

# SPDX-License-Identifier: GPL-2.0



from lib.py import ksft_exit, ksft_run, ksft_ge, RtnlAddrFamily

import socket



IPV4_ALL_HOSTS_MULTICAST = b'\xe0\x00\x00\x01'



def dump_mcaddr_check(rtnl: RtnlAddrFamily) -> None:

    """

    Verify that at least one interface has the IPv4 all-hosts multicast address.

    At least the loopback interface should have this address.

    """



    addresses = rtnl.getmaddrs({"ifa-family": socket.AF_INET}, dump=True)



    all_host_multicasts = [

        addr for addr in addresses if addr['ifa-multicast'] == IPV4_ALL_HOSTS_MULTICAST

    ]



    ksft_ge(len(all_host_multicasts), 1,

            "No interface found with the IPv4 all-hosts multicast address")



def main() -> None:

    rtnl = RtnlAddrFamily()

    ksft_run([dump_mcaddr_check], args=(rtnl, ))

    ksft_exit()



if __name__ == "__main__":

    main()