selftests: netfilter: switch to socat for tests using -q option

The nc cmd(nmap-ncat) that distributed with Fedora/Red Hat does not have
option -q. This make some tests failed with:

	nc: invalid option -- 'q'

Let's switch to socat which is far more dependable.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Author: liuhangbin

tools/testing/selftests/netfilter/ipip-conntrack-mtu.sh

@@ -41,7 +41,7 @@ checktool (){
 
 checktool "iptables --version" "run test without iptables"
 checktool "ip -Version" "run test without ip tool"
-checktool "which nc" "run test without nc (netcat)"
+checktool "which socat" "run test without socat"
 checktool "ip netns add ${r_a}" "create net namespace"
 
 for n in ${r_b} ${r_w} ${c_a} ${c_b};do
@@ -60,11 +60,12 @@ trap cleanup EXIT
 test_path() {
 	msg="$1"
 
-	ip netns exec ${c_b} nc -n -w 3 -q 3 -u -l -p 5000 > ${rx} < /dev/null &
+	ip netns exec ${c_b} socat -t 3 - udp4-listen:5000,reuseaddr > ${rx} < /dev/null &
 
 	sleep 1
 	for i in 1 2 3; do
-		head -c1400 /dev/zero | tr "\000" "a" | ip netns exec ${c_a} nc -n -w 1 -u 192.168.20.2 5000
+		head -c1400 /dev/zero | tr "\000" "a" | \
+			ip netns exec ${c_a} socat -t 1 -u STDIN UDP:192.168.20.2:5000
 	done
 
 	wait
@@ -189,7 +190,7 @@ ip netns exec ${r_w} sysctl -q net.ipv4.conf.all.forwarding=1 > /dev/null
 #---------------------
 #Now we send a 1400 bytes UDP packet from Client A to Client B:
 
-# clienta:~# head -c1400 /dev/zero | tr "\000" "a" | nc -u 192.168.20.2 5000
+# clienta:~# head -c1400 /dev/zero | tr "\000" "a" | socat -u STDIN UDP:192.168.20.2:5000
 test_path "without"
 
 # The IPv4 stack on Client A already knows the PMTU to Client B, so the

tools/testing/selftests/netfilter/nf_nat_edemux.sh

@@ -76,23 +76,23 @@ ip netns exec $ns2 ip route add 10.96.0.1 via 192.168.1.1
 sleep 1
 
 # add a persistent connection from the other namespace
-ip netns exec $ns2 nc -q 10 -w 10 192.168.1.1 5201 > /dev/null &
+ip netns exec $ns2 socat -t 10 - TCP:192.168.1.1:5201 > /dev/null &
 
 sleep 1
 
 # ip daddr:dport will be rewritten to 192.168.1.1 5201
 # NAT must reallocate source port 10000 because
 # 192.168.1.2:10000 -> 192.168.1.1:5201 is already in use
-echo test | ip netns exec $ns2 nc -w 3 -q 3 10.96.0.1 443 >/dev/null
+echo test | ip netns exec $ns2 socat -t 3 -u STDIN TCP:10.96.0.1:443 >/dev/null
 ret=$?
 
 kill $iperfs
 
-# Check nc can connect to 10.96.0.1:443 (aka 192.168.1.1:5201).
+# Check socat can connect to 10.96.0.1:443 (aka 192.168.1.1:5201).
 if [ $ret -eq 0 ]; then
-	echo "PASS: nc can connect via NAT'd address"
+	echo "PASS: socat can connect via NAT'd address"
 else
-	echo "FAIL: nc cannot connect via NAT'd address"
+	echo "FAIL: socat cannot connect via NAT'd address"
 	exit 1
 fi