include/net/flow_dissector.h

   1 #ifndef _NET_FLOW_DISSECTOR_H
   2 #define _NET_FLOW_DISSECTOR_H
   3
   4 #include <linux/types.h>
   5 #include <linux/skbuff.h>
   6 #include <linux/in6.h>
   7 #include <uapi/linux/if_ether.h>
   8
   9 /**
  10  * struct flow_dissector_key_control:
  11  * @thoff: Transport header offset
  12  */
  13 struct flow_dissector_key_control {
  14         u16     thoff;
  15         u16     addr_type;
  16 };
  17
  18 /**
  19  * struct flow_dissector_key_basic:
  20  * @thoff: Transport header offset
  21  * @n_proto: Network header protocol (eg. IPv4/IPv6)
  22  * @ip_proto: Transport header protocol (eg. TCP/UDP)
  23  */
  24 struct flow_dissector_key_basic {
  25         __be16  n_proto;
  26         u8      ip_proto;
  27         u8      padding;
  28 };
  29
  30 struct flow_dissector_key_tags {
  31         u32     vlan_id:12,
  32                 flow_label:20;
  33 };
  34
  35 struct flow_dissector_key_keyid {
  36         __be32  keyid;
  37 };
  38
  39 /**
  40  * struct flow_dissector_key_ipv4_addrs:
  41  * @src: source ip address
  42  * @dst: destination ip address
  43  */
  44 struct flow_dissector_key_ipv4_addrs {
  45         /* (src,dst) must be grouped, in the same way than in IP header */
  46         __be32 src;
  47         __be32 dst;
  48 };
  49
  50 /**
  51  * struct flow_dissector_key_ipv6_addrs:
  52  * @src: source ip address
  53  * @dst: destination ip address
  54  */
  55 struct flow_dissector_key_ipv6_addrs {
  56         /* (src,dst) must be grouped, in the same way than in IP header */
  57         struct in6_addr src;
  58         struct in6_addr dst;
  59 };
  60
  61 /**
  62  * struct flow_dissector_key_tipc_addrs:
  63  * @srcnode: source node address
  64  */
  65 struct flow_dissector_key_tipc_addrs {
  66         __be32 srcnode;
  67 };
  68
  69 /**
  70  * struct flow_dissector_key_addrs:
  71  * @v4addrs: IPv4 addresses
  72  * @v6addrs: IPv6 addresses
  73  */
  74 struct flow_dissector_key_addrs {
  75         union {
  76                 struct flow_dissector_key_ipv4_addrs v4addrs;
  77                 struct flow_dissector_key_ipv6_addrs v6addrs;
  78                 struct flow_dissector_key_tipc_addrs tipcaddrs;
  79         };
  80 };
  81
  82 /**
  83  * flow_dissector_key_tp_ports:
  84  *      @ports: port numbers of Transport header
  85  *              src: source port number
  86  *              dst: destination port number
  87  */
  88 struct flow_dissector_key_ports {
  89         union {
  90                 __be32 ports;
  91                 struct {
  92                         __be16 src;
  93                         __be16 dst;
  94                 };
  95         };
  96 };
  97
  98
  99 /**
 100  * struct flow_dissector_key_eth_addrs:
 101  * @src: source Ethernet address
 102  * @dst: destination Ethernet address
 103  */
 104 struct flow_dissector_key_eth_addrs {
 105         /* (dst,src) must be grouped, in the same way than in ETH header */
 106         unsigned char dst[ETH_ALEN];
 107         unsigned char src[ETH_ALEN];
 108 };
 109
 110 enum flow_dissector_key_id {
 111         FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
 112         FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
 113         FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
 114         FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
 115         FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
 116         FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
 117         FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */
 118         FLOW_DISSECTOR_KEY_VLANID, /* struct flow_dissector_key_flow_tags */
 119         FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
 120         FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
 121         FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
 122
 123         FLOW_DISSECTOR_KEY_MAX,
 124 };
 125
 126 struct flow_dissector_key {
 127         enum flow_dissector_key_id key_id;
 128         size_t offset; /* offset of struct flow_dissector_key_*
 129                           in target the struct */
 130 };
 131
 132 struct flow_dissector {
 133         unsigned int used_keys; /* each bit repesents presence of one key id */
 134         unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
 135 };
 136
 137 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
 138                              const struct flow_dissector_key *key,
 139                              unsigned int key_count);
 140
 141 bool __skb_flow_dissect(const struct sk_buff *skb,
 142                         struct flow_dissector *flow_dissector,
 143                         void *target_container,
 144                         void *data, __be16 proto, int nhoff, int hlen);
 145
 146 static inline bool skb_flow_dissect(const struct sk_buff *skb,
 147                                     struct flow_dissector *flow_dissector,
 148                                     void *target_container)
 149 {
 150         return __skb_flow_dissect(skb, flow_dissector, target_container,
 151                                   NULL, 0, 0, 0);
 152 }
 153
 154 struct flow_keys {
 155         struct flow_dissector_key_control control;
 156 #define FLOW_KEYS_HASH_START_FIELD basic
 157         struct flow_dissector_key_basic basic;
 158         struct flow_dissector_key_tags tags;
 159         struct flow_dissector_key_keyid keyid;
 160         struct flow_dissector_key_ports ports;
 161         struct flow_dissector_key_addrs addrs;
 162 };
 163
 164 #define FLOW_KEYS_HASH_OFFSET           \
 165         offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
 166
 167 __be32 flow_get_u32_src(const struct flow_keys *flow);
 168 __be32 flow_get_u32_dst(const struct flow_keys *flow);
 169
 170 extern struct flow_dissector flow_keys_dissector;
 171 extern struct flow_dissector flow_keys_buf_dissector;
 172
 173 static inline bool skb_flow_dissect_flow_keys(const struct sk_buff *skb,
 174                                               struct flow_keys *flow)
 175 {
 176         memset(flow, 0, sizeof(*flow));
 177         return __skb_flow_dissect(skb, &flow_keys_dissector, flow,
 178                                   NULL, 0, 0, 0);
 179 }
 180
 181 static inline bool skb_flow_dissect_flow_keys_buf(struct flow_keys *flow,
 182                                                   void *data, __be16 proto,
 183                                                   int nhoff, int hlen)
 184 {
 185         memset(flow, 0, sizeof(*flow));
 186         return __skb_flow_dissect(NULL, &flow_keys_buf_dissector, flow,
 187                                   data, proto, nhoff, hlen);
 188 }
 189
 190 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
 191                             void *data, int hlen_proto);
 192
 193 static inline __be32 skb_flow_get_ports(const struct sk_buff *skb,
 194                                         int thoff, u8 ip_proto)
 195 {
 196         return __skb_flow_get_ports(skb, thoff, ip_proto, NULL, 0);
 197 }
 198
 199 u32 flow_hash_from_keys(struct flow_keys *keys);
 200 void __skb_get_hash(struct sk_buff *skb);
 201 u32 skb_get_poff(const struct sk_buff *skb);
 202 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
 203                    const struct flow_keys *keys, int hlen);
 204
 205 /* struct flow_keys_digest:
 206  *
 207  * This structure is used to hold a digest of the full flow keys. This is a
 208  * larger "hash" of a flow to allow definitively matching specific flows where
 209  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
 210  * that it can by used in CB of skb (see sch_choke for an example).
 211  */
 212 #define FLOW_KEYS_DIGEST_LEN    16
 213 struct flow_keys_digest {
 214         u8      data[FLOW_KEYS_DIGEST_LEN];
 215 };
 216
 217 void make_flow_keys_digest(struct flow_keys_digest *digest,
 218                            const struct flow_keys *flow);
 219
 220 #endif