1 #ifndef _NET_FLOW_DISSECTOR_H
2 #define _NET_FLOW_DISSECTOR_H
4 #include <linux/types.h>
5 #include <linux/skbuff.h>
9 * struct flow_dissector_key_basic:
10 * @thoff: Transport header offset
11 * @n_proto: Network header protocol (eg. IPv4/IPv6)
12 * @ip_proto: Transport header protocol (eg. TCP/UDP)
14 struct flow_dissector_key_basic {
21 * struct flow_dissector_key_addrs:
22 * @src: source ip address in case of IPv4
23 * For IPv6 it contains 32bit hash of src address
24 * @dst: destination ip address in case of IPv4
25 * For IPv6 it contains 32bit hash of dst address
27 struct flow_dissector_key_addrs {
28 /* (src,dst) must be grouped, in the same way than in IP header */
34 * flow_dissector_key_tp_ports:
35 * @ports: port numbers of Transport header
36 * port16[0]: src port number
37 * port16[1]: dst port number
39 struct flow_dissector_key_ports {
47 * struct flow_dissector_key_ipv6_addrs:
48 * @src: source ip address
49 * @dst: destination ip address
51 struct flow_dissector_key_ipv6_addrs {
52 /* (src,dst) must be grouped, in the same way than in IP header */
57 enum flow_dissector_key_id {
58 FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
59 FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_addrs */
60 FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS, /* struct flow_dissector_key_addrs */
61 FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
62 FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
64 FLOW_DISSECTOR_KEY_MAX,
67 struct flow_dissector_key {
68 enum flow_dissector_key_id key_id;
69 size_t offset; /* offset of struct flow_dissector_key_*
70 in target the struct */
73 struct flow_dissector {
74 unsigned int used_keys; /* each bit repesents presence of one key id */
75 unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
78 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
79 const struct flow_dissector_key *key,
80 unsigned int key_count);
82 bool __skb_flow_dissect(const struct sk_buff *skb,
83 struct flow_dissector *flow_dissector,
84 void *target_container,
85 void *data, __be16 proto, int nhoff, int hlen);
87 static inline bool skb_flow_dissect(const struct sk_buff *skb,
88 struct flow_dissector *flow_dissector,
89 void *target_container)
91 return __skb_flow_dissect(skb, flow_dissector, target_container,
96 struct flow_dissector_key_addrs addrs;
97 struct flow_dissector_key_ports ports;
98 struct flow_dissector_key_basic basic;
101 extern struct flow_dissector flow_keys_dissector;
102 extern struct flow_dissector flow_keys_buf_dissector;
104 static inline bool skb_flow_dissect_flow_keys(const struct sk_buff *skb,
105 struct flow_keys *flow)
107 memset(flow, 0, sizeof(*flow));
108 return __skb_flow_dissect(skb, &flow_keys_dissector, flow,
112 static inline bool skb_flow_dissect_flow_keys_buf(struct flow_keys *flow,
113 void *data, __be16 proto,
116 memset(flow, 0, sizeof(*flow));
117 return __skb_flow_dissect(NULL, &flow_keys_buf_dissector, flow,
118 data, proto, nhoff, hlen);
121 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
122 void *data, int hlen_proto);
124 static inline __be32 skb_flow_get_ports(const struct sk_buff *skb,
125 int thoff, u8 ip_proto)
127 return __skb_flow_get_ports(skb, thoff, ip_proto, NULL, 0);
130 u32 flow_hash_from_keys(struct flow_keys *keys);
131 void __skb_get_hash(struct sk_buff *skb);
132 u32 skb_get_poff(const struct sk_buff *skb);
133 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
134 const struct flow_keys *keys, int hlen);
136 /* struct flow_keys_digest:
138 * This structure is used to hold a digest of the full flow keys. This is a
139 * larger "hash" of a flow to allow definitively matching specific flows where
140 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
141 * that it can by used in CB of skb (see sch_choke for an example).
143 #define FLOW_KEYS_DIGEST_LEN 16
144 struct flow_keys_digest {
145 u8 data[FLOW_KEYS_DIGEST_LEN];
148 void make_flow_keys_digest(struct flow_keys_digest *digest,
149 const struct flow_keys *flow);