Commit a3222dc9 authored by William Tu's avatar William Tu Committed by David S. Miller
Browse files

ip_gre: Refector the erpsan tunnel code. 



Move two erspan functions to header file, erspan.h, so ipv6
erspan implementation can use it.

Signed-off-by: default avatarWilliam Tu <u9012063@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 50e0f5c0

include/net/erspan.h

+51 −0
Original line number Diff line number Diff line
@@ -58,4 +58,55 @@ struct erspanhdr { 
	struct erspan_metadata md;

};



static inline u8 tos_to_cos(u8 tos)

{

	u8 dscp, cos;



	dscp = tos >> 2;

	cos = dscp >> 3;

	return cos;

}



static inline void erspan_build_header(struct sk_buff *skb,

				__be32 id, u32 index,

				bool truncate, bool is_ipv4)

{

	struct ethhdr *eth = eth_hdr(skb);

	enum erspan_encap_type enc_type;

	struct erspanhdr *ershdr;

	struct qtag_prefix {

		__be16 eth_type;

		__be16 tci;

	} *qp;

	u16 vlan_tci = 0;

	u8 tos;



	tos = is_ipv4 ? ip_hdr(skb)->tos :

			(ipv6_hdr(skb)->priority << 4) +

			(ipv6_hdr(skb)->flow_lbl[0] >> 4);



	enc_type = ERSPAN_ENCAP_NOVLAN;



	/* If mirrored packet has vlan tag, extract tci and

	 *  perserve vlan header in the mirrored frame.

	 */

	if (eth->h_proto == htons(ETH_P_8021Q)) {

		qp = (struct qtag_prefix *)(skb->data + 2 * ETH_ALEN);

		vlan_tci = ntohs(qp->tci);

		enc_type = ERSPAN_ENCAP_INFRAME;

	}



	skb_push(skb, sizeof(*ershdr));

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

	memset(ershdr, 0, sizeof(*ershdr));



	ershdr->ver_vlan = htons((vlan_tci & VLAN_MASK) |

				 (ERSPAN_VERSION << VER_OFFSET));

	ershdr->session_id = htons((u16)(ntohl(id) & ID_MASK) |

			   ((tos_to_cos(tos) << COS_OFFSET) & COS_MASK) |

			   (enc_type << EN_OFFSET & EN_MASK) |

			   ((truncate << T_OFFSET) & T_MASK));

	ershdr->md.index = htonl(index & INDEX_MASK);

}



#endif

net/ipv4/ip_gre.c

+5 −49
Original line number Diff line number Diff line
@@ -114,7 +114,8 @@ MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 
static struct rtnl_link_ops ipgre_link_ops __read_mostly;

static int ipgre_tunnel_init(struct net_device *dev);

static void erspan_build_header(struct sk_buff *skb,

				__be32 id, u32 index, bool truncate);

				__be32 id, u32 index,

				bool truncate, bool is_ipv4);



static unsigned int ipgre_net_id __read_mostly;

static unsigned int gre_tap_net_id __read_mostly;
@@ -589,7 +590,7 @@ static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev, 
		goto err_free_rt;



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

			    ntohl(md->index), truncate);

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



	gre_build_header(skb, 8, TUNNEL_SEQ,

			 htons(ETH_P_ERSPAN), 0, htonl(tunnel->o_seqno++));
@@ -668,52 +669,6 @@ static netdev_tx_t ipgre_xmit(struct sk_buff *skb, 
	return NETDEV_TX_OK;

}



static inline u8 tos_to_cos(u8 tos)

{

	u8 dscp, cos;



	dscp = tos >> 2;

	cos = dscp >> 3;

	return cos;

}



static void erspan_build_header(struct sk_buff *skb,

				__be32 id, u32 index, bool truncate)

{

	struct iphdr *iphdr = ip_hdr(skb);

	struct ethhdr *eth = eth_hdr(skb);

	enum erspan_encap_type enc_type;

	struct erspanhdr *ershdr;

	struct qtag_prefix {

		__be16 eth_type;

		__be16 tci;

	} *qp;

	u16 vlan_tci = 0;



	enc_type = ERSPAN_ENCAP_NOVLAN;



	/* If mirrored packet has vlan tag, extract tci and

	 *  perserve vlan header in the mirrored frame.

	 */

	if (eth->h_proto == htons(ETH_P_8021Q)) {

		qp = (struct qtag_prefix *)(skb->data + 2 * ETH_ALEN);

		vlan_tci = ntohs(qp->tci);

		enc_type = ERSPAN_ENCAP_INFRAME;

	}



	skb_push(skb, sizeof(*ershdr));

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

	memset(ershdr, 0, sizeof(*ershdr));



	ershdr->ver_vlan = htons((vlan_tci & VLAN_MASK) |

				 (ERSPAN_VERSION << VER_OFFSET));

	ershdr->session_id = htons((u16)(ntohl(id) & ID_MASK) |

			   ((tos_to_cos(iphdr->tos) << COS_OFFSET) & COS_MASK) |

			   (enc_type << EN_OFFSET & EN_MASK) |

			   ((truncate << T_OFFSET) & T_MASK));

	ershdr->md.index = htonl(index & INDEX_MASK);

}



static netdev_tx_t erspan_xmit(struct sk_buff *skb,

			       struct net_device *dev)

{
@@ -737,7 +692,8 @@ static netdev_tx_t erspan_xmit(struct sk_buff *skb, 
	}



	/* Push ERSPAN header */

	erspan_build_header(skb, tunnel->parms.o_key, tunnel->index, truncate);

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

			    truncate, true);

	tunnel->parms.o_flags &= ~TUNNEL_KEY;

	__gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_ERSPAN));

	return NETDEV_TX_OK;