#!/bin/bash
#
# This test is for basic NAT functionality: snat, dnat, redirect, masquerade.
#

# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4
ret=0

nft --version > /dev/null 2>&1
if [ $? -ne 0 ];then
	echo "SKIP: Could not run test without nft tool"
	exit $ksft_skip
fi

ip -Version > /dev/null 2>&1
if [ $? -ne 0 ];then
	echo "SKIP: Could not run test without ip tool"
	exit $ksft_skip
fi

ip netns add ns0
ip netns add ns1
ip netns add ns2

ip link add veth0 netns ns0 type veth peer name eth0 netns ns1 > /dev/null 2>&1
if [ $? -ne 0 ];then
    echo "SKIP: No virtual ethernet pair device support in kernel"
    exit $ksft_skip
fi
ip link add veth1 netns ns0 type veth peer name eth0 netns ns2

ip -net ns0 link set lo up
ip -net ns0 link set veth0 up
ip -net ns0 addr add 10.0.1.1/24 dev veth0
ip -net ns0 addr add dead:1::1/64 dev veth0

ip -net ns0 link set veth1 up
ip -net ns0 addr add 10.0.2.1/24 dev veth1
ip -net ns0 addr add dead:2::1/64 dev veth1

for i in 1 2; do
  ip -net ns$i link set lo up
  ip -net ns$i link set eth0 up
  ip -net ns$i addr add 10.0.$i.99/24 dev eth0
  ip -net ns$i route add default via 10.0.$i.1
  ip -net ns$i addr add dead:$i::99/64 dev eth0
  ip -net ns$i route add default via dead:$i::1
done

bad_counter()
{
	local ns=$1
	local counter=$2
	local expect=$3

	echo "ERROR: $counter counter in $ns has unexpected value (expected $expect)" 1>&2
	ip netns exec $ns nft list counter inet filter $counter 1>&2
}

check_counters()
{
	ns=$1
	local lret=0

	cnt=$(ip netns exec $ns nft list counter inet filter ns0in | grep -q "packets 1 bytes 84")
	if [ $? -ne 0 ]; then
		bad_counter $ns ns0in "packets 1 bytes 84"
		lret=1
	fi
	cnt=$(ip netns exec $ns nft list counter inet filter ns0out | grep -q "packets 1 bytes 84")
	if [ $? -ne 0 ]; then
		bad_counter $ns ns0out "packets 1 bytes 84"
		lret=1
	fi

	expect="packets 1 bytes 104"
	cnt=$(ip netns exec $ns nft list counter inet filter ns0in6 | grep -q "$expect")
	if [ $? -ne 0 ]; then
		bad_counter $ns ns0in6 "$expect"
		lret=1
	fi
	cnt=$(ip netns exec $ns nft list counter inet filter ns0out6 | grep -q "$expect")
	if [ $? -ne 0 ]; then
		bad_counter $ns ns0out6 "$expect"
		lret=1
	fi

	return $lret
}

check_ns0_counters()
{
	local ns=$1
	local lret=0

	cnt=$(ip netns exec ns0 nft list counter inet filter ns0in | grep -q "packets 0 bytes 0")
	if [ $? -ne 0 ]; then
		bad_counter ns0 ns0in "packets 0 bytes 0"
		lret=1
	fi

	cnt=$(ip netns exec ns0 nft list counter inet filter ns0in6 | grep -q "packets 0 bytes 0")
	if [ $? -ne 0 ]; then
		bad_counter ns0 ns0in6 "packets 0 bytes 0"
		lret=1
	fi

	cnt=$(ip netns exec ns0 nft list counter inet filter ns0out | grep -q "packets 0 bytes 0")
	if [ $? -ne 0 ]; then
		bad_counter ns0 ns0out "packets 0 bytes 0"
		lret=1
	fi
	cnt=$(ip netns exec ns0 nft list counter inet filter ns0out6 | grep -q "packets 0 bytes 0")
	if [ $? -ne 0 ]; then
		bad_counter ns0 ns0out6 "packets 0 bytes 0"
		lret=1
	fi

	for dir in "in" "out" ; do
		expect="packets 1 bytes 84"
		cnt=$(ip netns exec ns0 nft list counter inet filter ${ns}${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 $ns$dir "$expect"
			lret=1
		fi

		expect="packets 1 bytes 104"
		cnt=$(ip netns exec ns0 nft list counter inet filter ${ns}${dir}6 | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 $ns$dir6 "$expect"
			lret=1
		fi
	done

	return $lret
}

reset_counters()
{
	for i in 0 1 2;do
		ip netns exec ns$i nft reset counters inet > /dev/null
	done
}

test_local_dnat6()
{
	local lret=0
ip netns exec ns0 nft -f - <<EOF
table ip6 nat {
	chain output {
		type nat hook output priority 0; policy accept;
		ip6 daddr dead:1::99 dnat to dead:2::99
	}
}
EOF
	if [ $? -ne 0 ]; then
		echo "SKIP: Could not add add ip6 dnat hook"
		return $ksft_skip
	fi

	# ping netns1, expect rewrite to netns2
	ip netns exec ns0 ping -q -c 1 dead:1::99 > /dev/null
	if [ $? -ne 0 ]; then
		lret=1
		echo "ERROR: ping6 failed"
		return $lret
	fi

	expect="packets 0 bytes 0"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 ns1$dir "$expect"
			lret=1
		fi
	done

	expect="packets 1 bytes 104"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 ns2$dir "$expect"
			lret=1
		fi
	done

	# expect 0 count in ns1
	expect="packets 0 bytes 0"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi
	done

	# expect 1 packet in ns2
	expect="packets 1 bytes 104"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns2 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns0$dir "$expect"
			lret=1
		fi
	done

	test $lret -eq 0 && echo "PASS: ipv6 ping to ns1 was NATted to ns2"
	ip netns exec ns0 nft flush chain ip6 nat output

	return $lret
}

test_local_dnat()
{
	local lret=0
ip netns exec ns0 nft -f - <<EOF
table ip nat {
	chain output {
		type nat hook output priority 0; policy accept;
		ip daddr 10.0.1.99 dnat to 10.0.2.99
	}
}
EOF
	# ping netns1, expect rewrite to netns2
	ip netns exec ns0 ping -q -c 1 10.0.1.99 > /dev/null
	if [ $? -ne 0 ]; then
		lret=1
		echo "ERROR: ping failed"
		return $lret
	fi

	expect="packets 0 bytes 0"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 ns1$dir "$expect"
			lret=1
		fi
	done

	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 ns2$dir "$expect"
			lret=1
		fi
	done

	# expect 0 count in ns1
	expect="packets 0 bytes 0"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi
	done

	# expect 1 packet in ns2
	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns2 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns0$dir "$expect"
			lret=1
		fi
	done

	test $lret -eq 0 && echo "PASS: ping to ns1 was NATted to ns2"

	ip netns exec ns0 nft flush chain ip nat output

	reset_counters
	ip netns exec ns0 ping -q -c 1 10.0.1.99 > /dev/null
	if [ $? -ne 0 ]; then
		lret=1
		echo "ERROR: ping failed"
		return $lret
	fi

	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns1$dir "$expect"
			lret=1
		fi
	done
	expect="packets 0 bytes 0"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 ns2$dir "$expect"
			lret=1
		fi
	done

	# expect 1 count in ns1
	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns0 ns0$dir "$expect"
			lret=1
		fi
	done

	# expect 0 packet in ns2
	expect="packets 0 bytes 0"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns2 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns2$dir "$expect"
			lret=1
		fi
	done

	test $lret -eq 0 && echo "PASS: ping to ns1 OK after nat output chain flush"

	return $lret
}


test_masquerade6()
{
	local lret=0

	ip netns exec ns0 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null

	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: cannot ping ns1 from ns2 via ipv6"
		return 1
		lret=1
	fi

	expect="packets 1 bytes 104"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns2$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	reset_counters

# add masquerading rule
ip netns exec ns0 nft -f - <<EOF
table ip6 nat {
	chain postrouting {
		type nat hook postrouting priority 0; policy accept;
		meta oif veth0 masquerade
	}
}
EOF
	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: cannot ping ns1 from ns2 with active ipv6 masquerading"
		lret=1
	fi

	# ns1 should have seen packets from ns0, due to masquerade
	expect="packets 1 bytes 104"
	for dir in "in6" "out6" ; do

		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	# ns1 should not have seen packets from ns2, due to masquerade
	expect="packets 0 bytes 0"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	ip netns exec ns0 nft flush chain ip6 nat postrouting
	if [ $? -ne 0 ]; then
		echo "ERROR: Could not flush ip6 nat postrouting" 1>&2
		lret=1
	fi

	test $lret -eq 0 && echo "PASS: IPv6 masquerade for ns2"

	return $lret
}

test_masquerade()
{
	local lret=0

	ip netns exec ns0 sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
	ip netns exec ns0 sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null

	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: canot ping ns1 from ns2"
		lret=1
	fi

	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns2$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	reset_counters

# add masquerading rule
ip netns exec ns0 nft -f - <<EOF
table ip nat {
	chain postrouting {
		type nat hook postrouting priority 0; policy accept;
		meta oif veth0 masquerade
	}
}
EOF
	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: cannot ping ns1 from ns2 with active ip masquerading"
		lret=1
	fi

	# ns1 should have seen packets from ns0, due to masquerade
	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns0${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	# ns1 should not have seen packets from ns2, due to masquerade
	expect="packets 0 bytes 0"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	ip netns exec ns0 nft flush chain ip nat postrouting
	if [ $? -ne 0 ]; then
		echo "ERROR: Could not flush nat postrouting" 1>&2
		lret=1
	fi

	test $lret -eq 0 && echo "PASS: IP masquerade for ns2"

	return $lret
}

test_redirect6()
{
	local lret=0

	ip netns exec ns0 sysctl net.ipv6.conf.all.forwarding=1 > /dev/null

	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: cannnot ping ns1 from ns2 via ipv6"
		lret=1
	fi

	expect="packets 1 bytes 104"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns2$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	reset_counters

# add redirect rule
ip netns exec ns0 nft -f - <<EOF
table ip6 nat {
	chain prerouting {
		type nat hook prerouting priority 0; policy accept;
		meta iif veth1 meta l4proto icmpv6 ip6 saddr dead:2::99 ip6 daddr dead:1::99 redirect
	}
}
EOF
	ip netns exec ns2 ping -q -c 1 dead:1::99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: cannot ping ns1 from ns2 with active ip6 redirect"
		lret=1
	fi

	# ns1 should have seen no packets from ns2, due to redirection
	expect="packets 0 bytes 0"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi
	done

	# ns0 should have seen packets from ns2, due to masquerade
	expect="packets 1 bytes 104"
	for dir in "in6" "out6" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi
	done

	ip netns exec ns0 nft delete table ip6 nat
	if [ $? -ne 0 ]; then
		echo "ERROR: Could not delete ip6 nat table" 1>&2
		lret=1
	fi

	test $lret -eq 0 && echo "PASS: IPv6 redirection for ns2"

	return $lret
}

test_redirect()
{
	local lret=0

	ip netns exec ns0 sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
	ip netns exec ns0 sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null

	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: cannot ping ns1 from ns2"
		lret=1
	fi

	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns2$dir "$expect"
			lret=1
		fi

		cnt=$(ip netns exec ns2 nft list counter inet filter ns1${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns2 ns1$dir "$expect"
			lret=1
		fi
	done

	reset_counters

# add redirect rule
ip netns exec ns0 nft -f - <<EOF
table ip nat {
	chain prerouting {
		type nat hook prerouting priority 0; policy accept;
		meta iif veth1 ip protocol icmp ip saddr 10.0.2.99 ip daddr 10.0.1.99 redirect
	}
}
EOF
	ip netns exec ns2 ping -q -c 1 10.0.1.99 > /dev/null # ping ns2->ns1
	if [ $? -ne 0 ] ; then
		echo "ERROR: cannot ping ns1 from ns2 with active ip redirect"
		lret=1
	fi

	# ns1 should have seen no packets from ns2, due to redirection
	expect="packets 0 bytes 0"
	for dir in "in" "out" ; do

		cnt=$(ip netns exec ns1 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi
	done

	# ns0 should have seen packets from ns2, due to masquerade
	expect="packets 1 bytes 84"
	for dir in "in" "out" ; do
		cnt=$(ip netns exec ns0 nft list counter inet filter ns2${dir} | grep -q "$expect")
		if [ $? -ne 0 ]; then
			bad_counter ns1 ns0$dir "$expect"
			lret=1
		fi
	done

	ip netns exec ns0 nft delete table ip nat
	if [ $? -ne 0 ]; then
		echo "ERROR: Could not delete nat table" 1>&2
		lret=1
	fi

	test $lret -eq 0 && echo "PASS: IP redirection for ns2"

	return $lret
}


# ip netns exec ns0 ping -c 1 -q 10.0.$i.99
for i in 0 1 2; do
ip netns exec ns$i nft -f - <<EOF
table inet filter {
	counter ns0in {}
	counter ns1in {}
	counter ns2in {}

	counter ns0out {}
	counter ns1out {}
	counter ns2out {}

	counter ns0in6 {}
	counter ns1in6 {}
	counter ns2in6 {}

	counter ns0out6 {}
	counter ns1out6 {}
	counter ns2out6 {}

	map nsincounter {
		type ipv4_addr : counter
		elements = { 10.0.1.1 : "ns0in",
			     10.0.2.1 : "ns0in",
			     10.0.1.99 : "ns1in",
			     10.0.2.99 : "ns2in" }
	}

	map nsincounter6 {
		type ipv6_addr : counter
		elements = { dead:1::1 : "ns0in6",
			     dead:2::1 : "ns0in6",
			     dead:1::99 : "ns1in6",
			     dead:2::99 : "ns2in6" }
	}

	map nsoutcounter {
		type ipv4_addr : counter
		elements = { 10.0.1.1 : "ns0out",
			     10.0.2.1 : "ns0out",
			     10.0.1.99: "ns1out",
			     10.0.2.99: "ns2out" }
	}

	map nsoutcounter6 {
		type ipv6_addr : counter
		elements = { dead:1::1 : "ns0out6",
			     dead:2::1 : "ns0out6",
			     dead:1::99 : "ns1out6",
			     dead:2::99 : "ns2out6" }
	}

	chain input {
		type filter hook input priority 0; policy accept;
		counter name ip saddr map @nsincounter
		icmpv6 type { "echo-request", "echo-reply" } counter name ip6 saddr map @nsincounter6
	}
	chain output {
		type filter hook output priority 0; policy accept;
		counter name ip daddr map @nsoutcounter
		icmpv6 type { "echo-request", "echo-reply" } counter name ip6 daddr map @nsoutcounter6
	}
}
EOF
done

sleep 3
# test basic connectivity
for i in 1 2; do
  ip netns exec ns0 ping -c 1 -q 10.0.$i.99 > /dev/null
  if [ $? -ne 0 ];then
  	echo "ERROR: Could not reach other namespace(s)" 1>&2
	ret=1
  fi

  ip netns exec ns0 ping -c 1 -q dead:$i::99 > /dev/null
  if [ $? -ne 0 ];then
	echo "ERROR: Could not reach other namespace(s) via ipv6" 1>&2
	ret=1
  fi
  check_counters ns$i
  if [ $? -ne 0 ]; then
	ret=1
  fi

  check_ns0_counters ns$i
  if [ $? -ne 0 ]; then
	ret=1
  fi
  reset_counters
done

if [ $ret -eq 0 ];then
	echo "PASS: netns routing/connectivity: ns0 can reach ns1 and ns2"
fi

reset_counters
test_local_dnat
test_local_dnat6

reset_counters
test_masquerade
test_masquerade6

reset_counters
test_redirect
test_redirect6

for i in 0 1 2; do ip netns del ns$i;done

exit $ret