diff mbox series

[net-next,v6,2/2] selftests/net: Add selftest for IPv4 RTM_GETMULTICAST support

Message ID 20250117081600.150863-2-yuyanghuang@google.com (mailing list archive)
State New
Headers show
Series [net-next,v6,1/2] netlink: support dumping IPv4 multicast addresses | expand

Commit Message

Yuyang Huang Jan. 17, 2025, 8:15 a.m. UTC
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: Yuyang Huang <yuyanghuang@google.com>
---
 Documentation/netlink/specs/rt_link.yaml | 70 ++++++++++++++++++++++++
 tools/testing/selftests/net/Makefile     |  1 +
 tools/testing/selftests/net/rtnetlink.py | 30 ++++++++++
 3 files changed, 101 insertions(+)
 create mode 100755 tools/testing/selftests/net/rtnetlink.py
diff mbox series

Patch

diff --git a/Documentation/netlink/specs/rt_link.yaml b/Documentation/netlink/specs/rt_link.yaml
index 0d492500c7e5..7dcd5fddac9d 100644
--- a/Documentation/netlink/specs/rt_link.yaml
+++ b/Documentation/netlink/specs/rt_link.yaml
@@ -92,6 +92,41 @@  definitions:
       -
         name: ifi-change
         type: u32
+  -
+    name: ifaddrmsg
+    type: struct
+    members:
+      -
+        name: ifa-family
+        type: u8
+      -
+        name: ifa-prefixlen
+        type: u8
+      -
+        name: ifa-flags
+        type: u8
+      -
+        name: ifa-scope
+        type: u8
+      -
+        name: ifa-index
+        type: u32
+  -
+    name: ifacacheinfo
+    type: struct
+    members:
+      -
+        name: ifa-prefered
+        type: u32
+      -
+        name: ifa-valid
+        type: u32
+      -
+        name: cstamp
+        type: u32
+      -
+        name: tstamp
+        type: u32
   -
     name: ifla-bridge-id
     type: struct
@@ -2253,6 +2288,18 @@  attribute-sets:
       -
         name: tailroom
         type: u16
+  -
+    name: ifmcaddr-attrs
+    attributes:
+      -
+        name: addr
+        type: binary
+        value: 7
+      -
+        name: cacheinfo
+        type: binary
+        struct: ifacacheinfo
+        value: 6
 
 sub-messages:
   -
@@ -2493,6 +2540,29 @@  operations:
         reply:
           value: 92
           attributes: *link-stats-attrs
+    -
+      name: getmaddrs
+      doc: Get / dump IPv4/IPv6 multicast addresses.
+      attribute-set: ifmcaddr-attrs
+      fixed-header: ifaddrmsg
+      do:
+        request:
+          value: 58
+          attributes:
+            - ifa-family
+            - ifa-index
+        reply:
+          value: 58
+          attributes: &mcaddr-attrs
+            - addr
+            - cacheinfo
+      dump:
+        request:
+          value: 58
+            - ifa-family
+        reply:
+          value: 58
+          attributes: *mcaddr-attrs
 
 mcast-groups:
   list:
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 73ee88d6b043..e2f03211f9b3 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -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
diff --git a/tools/testing/selftests/net/rtnetlink.py b/tools/testing/selftests/net/rtnetlink.py
new file mode 100755
index 000000000000..9b9dfbe4dd7b
--- /dev/null
+++ b/tools/testing/selftests/net/rtnetlink.py
@@ -0,0 +1,30 @@ 
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+from lib.py import ksft_exit, ksft_run, ksft_ge, RtnlFamily
+import socket
+
+IPV4_ALL_HOSTS_MULTICAST = b'\xe0\x00\x00\x01'
+
+def dump_mcaddr_check(rtnl: RtnlFamily) -> 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['addr'] == 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 = RtnlFamily()
+    ksft_run([dump_mcaddr_check], args=(rtnl, ))
+    ksft_exit()
+
+if __name__ == "__main__":
+    main()