Commit 3a9ab393 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'ipv6-add-ip6erspan-collect_md-mode' 

William Tu says:

====================
ipv6: add ip6erspan collect_md mode

Similar to erspan collect_md mode in ipv4, the first patch adds
support for ip6erspan collect metadata mode.  The second patch
adds the test case using bpf_skb_[gs]et_tunnel_key helpers.

The corresponding iproute2 patch:
https://marc.info/?l=linux-netdev&m=151251545410047&w=2


====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 92425c40 d37e3bb7

net/ipv6/ip6_gre.c

+85 −25
Original line number Diff line number Diff line
@@ -524,8 +524,37 @@ static int ip6erspan_rcv(struct sk_buff *skb, int gre_hdr_len, 
					   false, false) < 0)

			return PACKET_REJECT;



		if (tunnel->parms.collect_md) {

			struct metadata_dst *tun_dst;

			struct ip_tunnel_info *info;

			struct erspan_metadata *md;

			__be64 tun_id;

			__be16 flags;



			tpi->flags |= TUNNEL_KEY;

			flags = tpi->flags;

			tun_id = key32_to_tunnel_id(tpi->key);



			tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,

						  sizeof(*md));

			if (!tun_dst)

				return PACKET_REJECT;



			info = &tun_dst->u.tun_info;

			md = ip_tunnel_info_opts(info);

			if (!md)

				return PACKET_REJECT;



			md->index = index;

			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;

			info->options_len = sizeof(*md);



			ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);



		} else {

			tunnel->parms.index = ntohl(index);

			ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);

		}



		return PACKET_RCVD;

	}
@@ -857,6 +886,44 @@ static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb, 
	if (gre_handle_offloads(skb, false))

		goto tx_err;



	if (skb->len > dev->mtu + dev->hard_header_len) {

		pskb_trim(skb, dev->mtu + dev->hard_header_len);

		truncate = true;

	}



	t->parms.o_flags &= ~TUNNEL_KEY;

	IPCB(skb)->flags = 0;



	/* For collect_md mode, derive fl6 from the tunnel key,

	 * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.

	 */

	if (t->parms.collect_md) {

		struct ip_tunnel_info *tun_info;

		const struct ip_tunnel_key *key;

		struct erspan_metadata *md;



		tun_info = skb_tunnel_info(skb);

		if (unlikely(!tun_info ||

			     !(tun_info->mode & IP_TUNNEL_INFO_TX) ||

			     ip_tunnel_info_af(tun_info) != AF_INET6))

			return -EINVAL;



		key = &tun_info->key;

		memset(&fl6, 0, sizeof(fl6));

		fl6.flowi6_proto = IPPROTO_GRE;

		fl6.daddr = key->u.ipv6.dst;

		fl6.flowlabel = key->label;

		fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);



		dsfield = key->tos;

		md = ip_tunnel_info_opts(tun_info);

		if (!md)

			goto tx_err;



		erspan_build_header(skb, tunnel_id_to_key32(key->tun_id),

				    ntohl(md->index), truncate, false);



	} else {

		switch (skb->protocol) {

		case htons(ETH_P_IP):

			memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
@@ -875,24 +942,17 @@ static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb, 
			break;

		}



	if (skb->len > dev->mtu + dev->hard_header_len) {

		pskb_trim(skb, dev->mtu + dev->hard_header_len);

		truncate = true;

	}



		erspan_build_header(skb, t->parms.o_key, t->parms.index,

				    truncate, false);

	t->parms.o_flags &= ~TUNNEL_KEY;



	IPCB(skb)->flags = 0;

		fl6.daddr = t->parms.raddr;

	}



	/* Push GRE header. */

	gre_build_header(skb, 8, TUNNEL_SEQ,

			 htons(ETH_P_ERSPAN), 0, htonl(t->o_seqno++));



	/* TooBig packet may have updated dst->dev's mtu */

	if (dst && dst_mtu(dst) > dst->dev->mtu)

	if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)

		dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu);



	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,

samples/bpf/tcbpf2_kern.c

+58 −0
Original line number Diff line number Diff line
@@ -181,6 +181,64 @@ int _erspan_get_tunnel(struct __sk_buff *skb) 
	return TC_ACT_OK;

}



SEC("ip4ip6erspan_set_tunnel")

int _ip4ip6erspan_set_tunnel(struct __sk_buff *skb)

{

	struct bpf_tunnel_key key;

	struct erspan_metadata md;

	int ret;



	__builtin_memset(&key, 0x0, sizeof(key));

	key.remote_ipv6[3] = _htonl(0x11);

	key.tunnel_id = 2;

	key.tunnel_tos = 0;

	key.tunnel_ttl = 64;



	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),

				     BPF_F_TUNINFO_IPV6);

	if (ret < 0) {

		ERROR(ret);

		return TC_ACT_SHOT;

	}



	md.index = htonl(123);

	ret = bpf_skb_set_tunnel_opt(skb, &md, sizeof(md));

	if (ret < 0) {

		ERROR(ret);

		return TC_ACT_SHOT;

	}



	return TC_ACT_OK;

}



SEC("ip4ip6erspan_get_tunnel")

int _ip4ip6erspan_get_tunnel(struct __sk_buff *skb)

{

	char fmt[] = "key %d remote ip6 ::%x erspan index 0x%x\n";

	struct bpf_tunnel_key key;

	struct erspan_metadata md;

	u32 index;

	int ret;



	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);

	if (ret < 0) {

		ERROR(ret);

		return TC_ACT_SHOT;

	}



	ret = bpf_skb_get_tunnel_opt(skb, &md, sizeof(md));

	if (ret < 0) {

		ERROR(ret);

		return TC_ACT_SHOT;

	}



	index = bpf_ntohl(md.index);

	bpf_trace_printk(fmt, sizeof(fmt),

			key.tunnel_id, key.remote_ipv6[0], index);



	return TC_ACT_OK;

}



SEC("vxlan_set_tunnel")

int _vxlan_set_tunnel(struct __sk_buff *skb)

{

samples/bpf/test_tunnel_bpf.sh

+37 −0
Original line number Diff line number Diff line
@@ -70,6 +70,28 @@ function add_erspan_tunnel { 
	ip addr add dev $DEV 10.1.1.200/24

}



function add_ip6erspan_tunnel {



	# assign ipv6 address

	ip netns exec at_ns0 ip addr add ::11/96 dev veth0

	ip netns exec at_ns0 ip link set dev veth0 up

	ip addr add dev veth1 ::22/96

	ip link set dev veth1 up



	# in namespace

	ip netns exec at_ns0 \

		ip link add dev $DEV_NS type $TYPE seq key 2 erspan 123 \

		local ::11 remote ::22



	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24

	ip netns exec at_ns0 ip link set dev $DEV_NS up



	# out of namespace

	ip link add dev $DEV type $TYPE external

	ip addr add dev $DEV 10.1.1.200/24

	ip link set dev $DEV up

}



function add_vxlan_tunnel {

	# Set static ARP entry here because iptables set-mark works

	# on L3 packet, as a result not applying to ARP packets,
@@ -184,6 +206,18 @@ function test_erspan { 
	cleanup

}



function test_ip6erspan {

	TYPE=ip6erspan

	DEV_NS=ip6erspan00

	DEV=ip6erspan11

	config_device

	add_ip6erspan_tunnel

	attach_bpf $DEV ip4ip6erspan_set_tunnel ip4ip6erspan_get_tunnel

	ping6 -c 3 ::11

	ip netns exec at_ns0 ping -c 1 10.1.1.200

	cleanup

}



function test_vxlan {

	TYPE=vxlan

	DEV_NS=vxlan00
@@ -239,6 +273,7 @@ function cleanup { 
	ip link del vxlan11

	ip link del geneve11

	ip link del erspan11

	ip link del ip6erspan11

	pkill tcpdump

	pkill cat

	set -ex
@@ -254,6 +289,8 @@ echo "Testing IP6GRETAP tunnel..." 
test_ip6gretap

echo "Testing ERSPAN tunnel..."

test_erspan

echo "Testing IP6ERSPAN tunnel..."

test_ip6erspan

echo "Testing VXLAN tunnel..."

test_vxlan

echo "Testing GENEVE tunnel..."

CRA Git | Maintained and supported by SUSTech CRA and CCSE