[PATCH libnflog] utils: add minimal nfnlog test case

Check that nfulnl_test receives 4 log messages each for ping/ping6 packets.

Signed-off-by: Florian Westphal <[email protected]>
---
 Seems I forgot to send it, I have carried this locally for more than
 a month :-/

 utils/nfulnl_test.c  |  1 +
 utils/nfulnl_test.sh | 58 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)
 create mode 100755 utils/nfulnl_test.sh

diff --git a/utils/nfulnl_test.c b/utils/nfulnl_test.c
index 4f29f1757c81..840c0bea3a86 100644
--- a/utils/nfulnl_test.c
+++ b/utils/nfulnl_test.c
@@ -121,6 +121,7 @@ int main(int argc, char **argv)
 
 		/* handle messages in just-received packet */
 		nflog_handle_packet(h, buf, rv);
+		fflush(stdout);
 	}
 
 	printf("unbinding from group 100\n");
diff --git a/utils/nfulnl_test.sh b/utils/nfulnl_test.sh
new file mode 100755
index 000000000000..b23ccab04bae
--- /dev/null
+++ b/utils/nfulnl_test.sh
@@ -0,0 +1,58 @@
+#!/bin/bash
+
+# Configuration
+NFLOG_GROUP=0
+PING_COUNT=2
+out=""
+
+cleanup() {
+	rm -f "$out"
+}
+
+die() {
+	echo "$@"
+	exit 1
+}
+
+if [ "$1" = "" ]; then
+	# Re-execute in new network namespace
+	exec unshare -n -- "$0" "run"
+fi
+
+trap cleanup EXIT
+set -e
+out=$(mktemp)
+
+timeout 5 ./nfulnl_test > "$out" &
+
+# Create ruleset to log ICMP/ICMPv6
+nft -f - <<EOF
+table inet filter {
+	chain icmp-log {
+		type filter hook prerouting priority 0; policy accept;
+
+		meta l4proto icmp counter log group $NFLOG_GROUP prefix "test icmp "
+		meta l4proto ipv6-icmp counter log group $NFLOG_GROUP prefix "test icmp6 "
+	}
+}
+EOF
+
+# Ensure the namespace has loopback and can send traffic
+ip link set lo up
+
+sleep 1
+
+# Trigger ICMP echo requests to ourselves (127.0.0.1 and ::1)
+ping -q -c "$PING_COUNT" 127.0.0.1 > /dev/null
+ping6 -q -c "$PING_COUNT" ::1 > /dev/null
+
+wait
+
+set +e
+cnt4=$(grep -c '^hw_protocol=0x0800 hook=0 hw_addrlen=6 hw_addr=00:00:00:00:00:00 mark=0 indev=1 prefix="test icmp " payload_len=84' "$out")
+cnt6=$(grep -c '^hw_protocol=0x86dd hook=0 hw_addrlen=6 hw_addr=00:00:00:00:00:00 mark=0 indev=1 prefix="test icmp6 " payload_len=104' "$out")
+
+[ "$cnt4" -ne 4 ] && die "Expected 2 counts each for ipv4 and ipv6, got $cnt4, $cnt6"
+[ "$cnt6" -ne 4 ] && die "Expected 2 counts each for ipv4 and ipv6, got $cnt4, $cnt6"
+
+echo "Completed, 4 log lines found for ipv4 and ipv6 each"
-- 
2.54.0