net: erspan: introduce erspan v2 for ip_gre

The patch adds support for erspan version 2.  Not all features are
supported in this patch.  The SGT (security group tag), GRA (timestamp
granularity), FT (frame type) are set to fixed value.  Only hardware
ID and direction are configurable.  Optional subheader is also not
supported.

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 90 insertions, 15 deletions

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 3e37402147f3..004800b923c6 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -315,11 +315,26 @@ static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
 				return PACKET_REJECT;
 
 			memcpy(md, pkt_md, sizeof(*md));
+			md->version = ver;
+
 			info = &tun_dst->u.tun_info;
 			info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
 			info->options_len = sizeof(*md);
 		} else {
-			tunnel->index = ntohl(pkt_md->u.index);
+			tunnel->erspan_ver = ver;
+			if (ver == 1) {
+				tunnel->index = ntohl(pkt_md->u.index);
+			} else {
+				u16 md2_flags;
+				u16 dir, hwid;
+
+				md2_flags = ntohs(pkt_md->u.md2.flags);
+				dir = (md2_flags & DIR_MASK) >> DIR_OFFSET;
+				hwid = (md2_flags & HWID_MASK) >> HWID_OFFSET;
+				tunnel->dir = dir;
+				tunnel->hwid = hwid;
+			}
+
 		}
 
 		skb_reset_mac_header(skb);
@@ -413,7 +428,8 @@ static int gre_rcv(struct sk_buff *skb)
 	if (hdr_len < 0)
 		goto drop;
 
-	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN))) {
+	if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
+		     tpi.proto == htons(ETH_P_ERSPAN2))) {
 		if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
 			return 0;
 	}
@@ -568,6 +584,7 @@ static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev,
 	bool truncate = false;
 	struct flowi4 fl;
 	int tunnel_hlen;
+	int version;
 	__be16 df;
 
 	tun_info = skb_tunnel_info(skb);
@@ -576,9 +593,13 @@ static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev,
 		goto err_free_skb;
 
 	key = &tun_info->key;
+	md = ip_tunnel_info_opts(tun_info);
+	if (!md)
+		goto err_free_rt;
 
 	/* ERSPAN has fixed 8 byte GRE header */
-	tunnel_hlen = 8 + sizeof(struct erspan_base_hdr) + ERSPAN_V1_MDSIZE;
+	version = md->version;
+	tunnel_hlen = 8 + erspan_hdr_len(version);
 
 	rt = prepare_fb_xmit(skb, dev, &fl, tunnel_hlen);
 	if (!rt)
@@ -592,12 +613,23 @@ static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev,
 		truncate = true;
 	}
 
-	md = ip_tunnel_info_opts(tun_info);
-	if (!md)
-		goto err_free_rt;
+	if (version == 1) {
+		erspan_build_header(skb, tunnel_id_to_key32(key->tun_id),
+				    ntohl(md->u.index), truncate, true);
+	} else if (version == 2) {
+		u16 md2_flags;
+		u8 direction;
+		u16 hwid;
 
-	erspan_build_header(skb, tunnel_id_to_key32(key->tun_id),
-			    ntohl(md->u.index), truncate, true);
+		md2_flags = ntohs(md->u.md2.flags);
+		direction = (md2_flags & DIR_MASK) >> DIR_OFFSET;
+		hwid = (md2_flags & HWID_MASK) >> HWID_OFFSET;
+
+		erspan_build_header_v2(skb, tunnel_id_to_key32(key->tun_id),
+				       direction, hwid,	truncate, true);
+	} else {
+		goto err_free_rt;
+	}
 
 	gre_build_header(skb, 8, TUNNEL_SEQ,
 			 htons(ETH_P_ERSPAN), 0, htonl(tunnel->o_seqno++));
@@ -699,8 +731,14 @@ static netdev_tx_t erspan_xmit(struct sk_buff *skb,
 	}
 
 	/* Push ERSPAN header */
-	erspan_build_header(skb, tunnel->parms.o_key, tunnel->index,
-			    truncate, true);
+	if (tunnel->erspan_ver == 1)
+		erspan_build_header(skb, tunnel->parms.o_key, tunnel->index,
+				    truncate, true);
+	else
+		erspan_build_header_v2(skb, tunnel->parms.o_key,
+				       tunnel->dir, tunnel->hwid,
+				       truncate, true);
+
 	tunnel->parms.o_flags &= ~TUNNEL_KEY;
 	__gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_ERSPAN));
 	return NETDEV_TX_OK;
@@ -1172,13 +1210,32 @@ static int ipgre_netlink_parms(struct net_device *dev,
 	if (data[IFLA_GRE_FWMARK])
 		*fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
 
-	if (data[IFLA_GRE_ERSPAN_INDEX]) {
-		t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
+	if (data[IFLA_GRE_ERSPAN_VER]) {
+		t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
 
-		if (t->index & ~INDEX_MASK)
+		if (t->erspan_ver != 1 && t->erspan_ver != 2)
 			return -EINVAL;
 	}
 
+	if (t->erspan_ver == 1) {
+		if (data[IFLA_GRE_ERSPAN_INDEX]) {
+			t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
+			if (t->index & ~INDEX_MASK)
+				return -EINVAL;
+		}
+	} else if (t->erspan_ver == 2) {
+		if (data[IFLA_GRE_ERSPAN_DIR]) {
+			t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
+			if (t->dir & ~(DIR_MASK >> DIR_OFFSET))
+				return -EINVAL;
+		}
+		if (data[IFLA_GRE_ERSPAN_HWID]) {
+			t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
+			if (t->hwid & ~(HWID_MASK >> HWID_OFFSET))
+				return -EINVAL;
+		}
+	}
+
 	return 0;
 }
 
@@ -1245,7 +1302,7 @@ static int erspan_tunnel_init(struct net_device *dev)
 	tunnel->tun_hlen = 8;
 	tunnel->parms.iph.protocol = IPPROTO_GRE;
 	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
-		       sizeof(struct erspan_base_hdr) + ERSPAN_V1_MDSIZE;
+		       erspan_hdr_len(tunnel->erspan_ver);
 	t_hlen = tunnel->hlen + sizeof(struct iphdr);
 
 	dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4;
@@ -1375,6 +1432,12 @@ static size_t ipgre_get_size(const struct net_device *dev)
 		nla_total_size(4) +
 		/* IFLA_GRE_ERSPAN_INDEX */
 		nla_total_size(4) +
+		/* IFLA_GRE_ERSPAN_VER */
+		nla_total_size(1) +
+		/* IFLA_GRE_ERSPAN_DIR */
+		nla_total_size(1) +
+		/* IFLA_GRE_ERSPAN_HWID */
+		nla_total_size(2) +
 		0;
 }
 
@@ -1417,9 +1480,18 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
 			goto nla_put_failure;
 	}
 
-	if (t->index)
+	if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
+		goto nla_put_failure;
+
+	if (t->erspan_ver == 1) {
 		if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
 			goto nla_put_failure;
+	} else if (t->erspan_ver == 2) {
+		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
+			goto nla_put_failure;
+		if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
+			goto nla_put_failure;
+	}
 
 	return 0;
 
@@ -1455,6 +1527,9 @@ static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
 	[IFLA_GRE_IGNORE_DF]	= { .type = NLA_U8 },
 	[IFLA_GRE_FWMARK]	= { .type = NLA_U32 },
 	[IFLA_GRE_ERSPAN_INDEX]	= { .type = NLA_U32 },
+	[IFLA_GRE_ERSPAN_VER]	= { .type = NLA_U8 },
+	[IFLA_GRE_ERSPAN_DIR]	= { .type = NLA_U8 },
+	[IFLA_GRE_ERSPAN_HWID]	= { .type = NLA_U16 },
 };
 
 static struct rtnl_link_ops ipgre_link_ops __read_mostly = {