From a3222dc95ca751cdc5f6ac3c9b092b160b73ed9f Mon Sep 17 00:00:00 2001 From: William Tu Date: Thu, 30 Nov 2017 11:51:27 -0800 Subject: 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: William Tu Signed-off-by: David S. Miller --- include/net/erspan.h | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) (limited to 'include/net/erspan.h') diff --git a/include/net/erspan.h b/include/net/erspan.h index ca94fc86865e..6e758d08c9ee 100644 --- a/include/net/erspan.h +++ b/include/net/erspan.h @@ -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 -- cgit