tests/shell: skip map query if kernel lacks support

On recent kernels one can perform a lookup in a map without a destination
register (i.e., treat the map like a set -- pure existence check).

Add a feature probe and work around the missing feature in
typeof_maps_add_delete: do the test with a simplified ruleset,

Indicate skipped even though a reduced test was run (earlier errors
cause a failure) to not trigger dump validation error.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Thomas Haller <thaller@redhat.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/tests/shell/features/map_lookup.nft b/tests/shell/features/map_lookup.nft
new file mode 100644
index 00000000..06c4c9d9
--- /dev/null
+++ b/tests/shell/features/map_lookup.nft
@@ -0,0 +1,11 @@
+# a4878eeae390 ("netfilter: nf_tables: relax set/map validation checks")
+# v6.5-rc1~163^2~256^2~8
+table ip t {
+        map m {
+                typeof ip daddr : meta mark
+        }
+
+        chain c {
+                ip saddr @m
+        }
+}