Commit 5a963eb6 authored by William Tu's avatar William Tu Committed by David S. Miller
Browse files

ip6_gre: Add ERSPAN native tunnel support 



The patch adds support for ERSPAN tunnel over ipv6.

Signed-off-by: default avatarWilliam Tu <u9012063@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 898b2979

include/net/ip6_tunnel.h

+1 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ struct __ip6_tnl_parm { 
	__be32			o_key;



	__u32			fwmark;

	__u32			index;	/* ERSPAN type II index */

};



/* IPv6 tunnel */

net/ipv6/ip6_gre.c

+266 −4
Original line number Diff line number Diff line
@@ -55,6 +55,7 @@ 
#include <net/ip6_route.h>

#include <net/ip6_tunnel.h>

#include <net/gre.h>

#include <net/erspan.h>





static bool log_ecn_error = true;
@@ -73,6 +74,7 @@ struct ip6gre_net { 


static struct rtnl_link_ops ip6gre_link_ops __read_mostly;

static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;

static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;

static int ip6gre_tunnel_init(struct net_device *dev);

static void ip6gre_tunnel_setup(struct net_device *dev);

static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
@@ -121,7 +123,8 @@ static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev, 
	unsigned int h1 = HASH_KEY(key);

	struct ip6_tnl *t, *cand = NULL;

	struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);

	int dev_type = (gre_proto == htons(ETH_P_TEB)) ?

	int dev_type = (gre_proto == htons(ETH_P_TEB) ||

			gre_proto == htons(ETH_P_ERSPAN)) ?

		       ARPHRD_ETHER : ARPHRD_IP6GRE;

	int score, cand_score = 4;
@@ -468,6 +471,41 @@ static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi) 
	return PACKET_REJECT;

}



static int ip6erspan_rcv(struct sk_buff *skb, int gre_hdr_len,

			 struct tnl_ptk_info *tpi)

{

	const struct ipv6hdr *ipv6h;

	struct erspanhdr *ershdr;

	struct ip6_tnl *tunnel;

	__be32 index;



	ipv6h = ipv6_hdr(skb);

	ershdr = (struct erspanhdr *)skb->data;



	if (unlikely(!pskb_may_pull(skb, sizeof(*ershdr))))

		return PACKET_REJECT;



	tpi->key = cpu_to_be32(ntohs(ershdr->session_id) & ID_MASK);

	index = ershdr->md.index;



	tunnel = ip6gre_tunnel_lookup(skb->dev,

				      &ipv6h->saddr, &ipv6h->daddr, tpi->key,

				      tpi->proto);

	if (tunnel) {

		if (__iptunnel_pull_header(skb, sizeof(*ershdr),

					   htons(ETH_P_TEB),

					   false, false) < 0)

			return PACKET_REJECT;



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

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



		return PACKET_RCVD;

	}



	return PACKET_REJECT;

}



static int gre_rcv(struct sk_buff *skb)

{

	struct tnl_ptk_info tpi;
@@ -481,6 +519,12 @@ static int gre_rcv(struct sk_buff *skb) 
	if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))

		goto drop;



	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN))) {

		if (ip6erspan_rcv(skb, hdr_len, &tpi) == PACKET_RCVD)

			return 0;

		goto drop;

	}



	if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)

		return 0;
@@ -732,6 +776,88 @@ static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 
	return NETDEV_TX_OK;

}



static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,

					 struct net_device *dev)

{

	struct ipv6hdr *ipv6h = ipv6_hdr(skb);

	struct ip6_tnl *t = netdev_priv(dev);

	struct dst_entry *dst = skb_dst(skb);

	struct net_device_stats *stats;

	bool truncate = false;

	int encap_limit = -1;

	__u8 dsfield = false;

	struct flowi6 fl6;

	int err = -EINVAL;

	__u32 mtu;



	if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))

		goto tx_err;



	if (gre_handle_offloads(skb, false))

		goto tx_err;



	switch (skb->protocol) {

	case htons(ETH_P_IP):

		memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));

		prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,

					 &dsfield, &encap_limit);

		break;

	case htons(ETH_P_IPV6):

		if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))

			goto tx_err;

		if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,

					     &dsfield, &encap_limit))

			goto tx_err;

		break;

	default:

		memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));

		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)

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



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

			   NEXTHDR_GRE);

	if (err != 0) {

		/* XXX: send ICMP error even if DF is not set. */

		if (err == -EMSGSIZE) {

			if (skb->protocol == htons(ETH_P_IP))

				icmp_send(skb, ICMP_DEST_UNREACH,

					  ICMP_FRAG_NEEDED, htonl(mtu));

			else

				icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);

		}



		goto tx_err;

	}

	return NETDEV_TX_OK;



tx_err:

	stats = &t->dev->stats;

	stats->tx_errors++;

	stats->tx_dropped++;

	kfree_skb(skb);

	return NETDEV_TX_OK;

}



static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)

{

	struct net_device *dev = t->dev;
@@ -1111,7 +1237,6 @@ static void ip6gre_fb_tunnel_init(struct net_device *dev) 
	dev_hold(dev);

}





static struct inet6_protocol ip6gre_protocol __read_mostly = {

	.handler     = gre_rcv,

	.err_handler = ip6gre_err,
@@ -1126,7 +1251,8 @@ static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 


	for_each_netdev_safe(net, dev, aux)

		if (dev->rtnl_link_ops == &ip6gre_link_ops ||

		    dev->rtnl_link_ops == &ip6gre_tap_ops)

		    dev->rtnl_link_ops == &ip6gre_tap_ops ||

		    dev->rtnl_link_ops == &ip6erspan_tap_ops)

			unregister_netdevice_queue(dev, head);



	for (prio = 0; prio < 4; prio++) {
@@ -1248,6 +1374,47 @@ static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 
	return ip6gre_tunnel_validate(tb, data, extack);

}



static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],

				  struct netlink_ext_ack *extack)

{

	__be16 flags = 0;

	int ret;



	if (!data)

		return 0;



	ret = ip6gre_tap_validate(tb, data, extack);

	if (ret)

		return ret;



	/* ERSPAN should only have GRE sequence and key flag */

	if (data[IFLA_GRE_OFLAGS])

		flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);

	if (data[IFLA_GRE_IFLAGS])

		flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);

	if (!data[IFLA_GRE_COLLECT_METADATA] &&

	    flags != (GRE_SEQ | GRE_KEY))

		return -EINVAL;



	/* ERSPAN Session ID only has 10-bit. Since we reuse

	 * 32-bit key field as ID, check it's range.

	 */

	if (data[IFLA_GRE_IKEY] &&

	    (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))

		return -EINVAL;



	if (data[IFLA_GRE_OKEY] &&

	    (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))

		return -EINVAL;



	if (data[IFLA_GRE_ERSPAN_INDEX]) {

		u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);



		if (index & ~INDEX_MASK)

			return -EINVAL;

	}

	return 0;

}



static void ip6gre_netlink_parms(struct nlattr *data[],

				struct __ip6_tnl_parm *parms)
@@ -1294,6 +1461,9 @@ static void ip6gre_netlink_parms(struct nlattr *data[], 


	if (data[IFLA_GRE_FWMARK])

		parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);



	if (data[IFLA_GRE_ERSPAN_INDEX])

		parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);

}



static int ip6gre_tap_init(struct net_device *dev)
@@ -1330,6 +1500,59 @@ static const struct net_device_ops ip6gre_tap_netdev_ops = { 
		       NETIF_F_HIGHDMA |		\

		       NETIF_F_HW_CSUM)



static int ip6erspan_tap_init(struct net_device *dev)

{

	struct ip6_tnl *tunnel;

	int t_hlen;

	int ret;



	tunnel = netdev_priv(dev);



	tunnel->dev = dev;

	tunnel->net = dev_net(dev);

	strcpy(tunnel->parms.name, dev->name);



	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);

	if (!dev->tstats)

		return -ENOMEM;



	ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);

	if (ret) {

		free_percpu(dev->tstats);

		dev->tstats = NULL;

		return ret;

	}



	tunnel->tun_hlen = 8;

	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +

		       sizeof(struct erspanhdr);

	t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);



	dev->hard_header_len = LL_MAX_HEADER + t_hlen;

	dev->mtu = ETH_DATA_LEN - t_hlen;

	if (dev->type == ARPHRD_ETHER)

		dev->mtu -= ETH_HLEN;

	if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))

		dev->mtu -= 8;



	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;

	tunnel = netdev_priv(dev);

	ip6gre_tnl_link_config(tunnel, 1);



	return 0;

}



static const struct net_device_ops ip6erspan_netdev_ops = {

	.ndo_init =		ip6erspan_tap_init,

	.ndo_uninit =		ip6gre_tunnel_uninit,

	.ndo_start_xmit =	ip6erspan_tunnel_xmit,

	.ndo_set_mac_address =	eth_mac_addr,

	.ndo_validate_addr =	eth_validate_addr,

	.ndo_change_mtu =	ip6_tnl_change_mtu,

	.ndo_get_stats64 =	ip_tunnel_get_stats64,

	.ndo_get_iflink =	ip6_tnl_get_iflink,

};



static void ip6gre_tap_setup(struct net_device *dev)

{
@@ -1521,6 +1744,8 @@ static size_t ip6gre_get_size(const struct net_device *dev) 
		nla_total_size(2) +

		/* IFLA_GRE_FWMARK */

		nla_total_size(4) +

		/* IFLA_GRE_ERSPAN_INDEX */

		nla_total_size(4) +

		0;

}
@@ -1542,7 +1767,8 @@ static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 
	    nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||

	    nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||

	    nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||

	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))

	    nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark) ||

	    nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))

		goto nla_put_failure;



	if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
@@ -1578,8 +1804,23 @@ static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 
	[IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },

	[IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },

	[IFLA_GRE_FWMARK]       = { .type = NLA_U32 },

	[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },

};



static void ip6erspan_tap_setup(struct net_device *dev)

{

	ether_setup(dev);



	dev->netdev_ops = &ip6erspan_netdev_ops;

	dev->needs_free_netdev = true;

	dev->priv_destructor = ip6gre_dev_free;



	dev->features |= NETIF_F_NETNS_LOCAL;

	dev->priv_flags &= ~IFF_TX_SKB_SHARING;

	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;

	netif_keep_dst(dev);

}



static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {

	.kind		= "ip6gre",

	.maxtype	= IFLA_GRE_MAX,
@@ -1609,6 +1850,20 @@ static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 
	.get_link_net	= ip6_tnl_get_link_net,

};



static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {

	.kind		= "ip6erspan",

	.maxtype	= IFLA_GRE_MAX,

	.policy		= ip6gre_policy,

	.priv_size	= sizeof(struct ip6_tnl),

	.setup		= ip6erspan_tap_setup,

	.validate	= ip6erspan_tap_validate,

	.newlink	= ip6gre_newlink,

	.changelink	= ip6gre_changelink,

	.get_size	= ip6gre_get_size,

	.fill_info	= ip6gre_fill_info,

	.get_link_net	= ip6_tnl_get_link_net,

};



/*

 *	And now the modules code and kernel interface.

 */
@@ -1637,9 +1892,15 @@ static int __init ip6gre_init(void) 
	if (err < 0)

		goto tap_ops_failed;



	err = rtnl_link_register(&ip6erspan_tap_ops);

	if (err < 0)

		goto erspan_link_failed;



out:

	return err;



erspan_link_failed:

	rtnl_link_unregister(&ip6gre_tap_ops);

tap_ops_failed:

	rtnl_link_unregister(&ip6gre_link_ops);

rtnl_link_failed:
@@ -1653,6 +1914,7 @@ static void __exit ip6gre_fini(void) 
{

	rtnl_link_unregister(&ip6gre_tap_ops);

	rtnl_link_unregister(&ip6gre_link_ops);

	rtnl_link_unregister(&ip6erspan_tap_ops);

	inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);

	unregister_pernet_device(&ip6gre_net_ops);

}