1 #include <linux/skbuff.h>
3 #include <linux/ipv6.h>
4 #include <linux/if_vlan.h>
6 #include <linux/if_tunnel.h>
7 #include <linux/if_pppox.h>
8 #include <linux/ppp_defs.h>
9 #include <net/flow_keys.h>
11 /* copy saddr & daddr, possibly using 64bit load/store
12 * Equivalent to : flow->src = iph->saddr;
13 * flow->dst = iph->daddr;
15 static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *iph)
17 BUILD_BUG_ON(offsetof(typeof(*flow), dst) !=
18 offsetof(typeof(*flow), src) + sizeof(flow->src));
19 memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst));
22 bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
24 int poff, nhoff = skb_network_offset(skb);
26 __be16 proto = skb->protocol;
28 memset(flow, 0, sizeof(*flow));
32 case __constant_htons(ETH_P_IP): {
33 const struct iphdr *iph;
36 iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
40 if (ip_is_fragment(iph))
43 ip_proto = iph->protocol;
44 iph_to_flow_copy_addrs(flow, iph);
45 nhoff += iph->ihl * 4;
48 case __constant_htons(ETH_P_IPV6): {
49 const struct ipv6hdr *iph;
52 iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
56 ip_proto = iph->nexthdr;
57 flow->src = iph->saddr.s6_addr32[3];
58 flow->dst = iph->daddr.s6_addr32[3];
59 nhoff += sizeof(struct ipv6hdr);
62 case __constant_htons(ETH_P_8021Q): {
63 const struct vlan_hdr *vlan;
64 struct vlan_hdr _vlan;
66 vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan);
70 proto = vlan->h_vlan_encapsulated_proto;
71 nhoff += sizeof(*vlan);
74 case __constant_htons(ETH_P_PPP_SES): {
79 hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
83 nhoff += PPPOE_SES_HLEN;
85 case __constant_htons(PPP_IP):
87 case __constant_htons(PPP_IPV6):
104 hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
108 * Only look inside GRE if version zero and no
111 if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) {
114 if (hdr->flags & GRE_CSUM)
116 if (hdr->flags & GRE_KEY)
118 if (hdr->flags & GRE_SEQ)
130 flow->ip_proto = ip_proto;
131 poff = proto_ports_offset(ip_proto);
133 __be32 *ports, _ports;
136 ports = skb_header_pointer(skb, nhoff, sizeof(_ports), &_ports);
138 flow->ports = *ports;
143 EXPORT_SYMBOL(skb_flow_dissect);