LXR linux/include/net/flow

   1#ifndef _NET_FLOW_DISSECTOR_H
   2#define _NET_FLOW_DISSECTOR_H
   3
   4#include <linux/types.h>
   5#include <linux/in6.h>
   6#include <uapi/linux/if_ether.h>
   7
   8/**
   9 * struct flow_dissector_key_control:
  10 * @thoff: Transport header offset
  11 */
  12struct flow_dissector_key_control {
  13        u16     thoff;
  14        u16     addr_type;
  15        u32     flags;
  16};
  17
  18#define FLOW_DIS_IS_FRAGMENT    BIT(0)
  19#define FLOW_DIS_FIRST_FRAG     BIT(1)
  20#define FLOW_DIS_ENCAPSULATION  BIT(2)
  21
  22/**
  23 * struct flow_dissector_key_basic:
  24 * @thoff: Transport header offset
  25 * @n_proto: Network header protocol (eg. IPv4/IPv6)
  26 * @ip_proto: Transport header protocol (eg. TCP/UDP)
  27 */
  28struct flow_dissector_key_basic {
  29        __be16  n_proto;
  30        u8      ip_proto;
  31        u8      padding;
  32};
  33
  34struct flow_dissector_key_tags {
  35        u32     flow_label;
  36};
  37
  38struct flow_dissector_key_vlan {
  39        u16     vlan_id:12,
  40                vlan_priority:3;
  41        u16     padding;
  42};
  43
  44struct flow_dissector_key_keyid {
  45        __be32  keyid;
  46};
  47
  48/**
  49 * struct flow_dissector_key_ipv4_addrs:
  50 * @src: source ip address
  51 * @dst: destination ip address
  52 */
  53struct flow_dissector_key_ipv4_addrs {
  54        /* (src,dst) must be grouped, in the same way than in IP header */
  55        __be32 src;
  56        __be32 dst;
  57};
  58
  59/**
  60 * struct flow_dissector_key_ipv6_addrs:
  61 * @src: source ip address
  62 * @dst: destination ip address
  63 */
  64struct flow_dissector_key_ipv6_addrs {
  65        /* (src,dst) must be grouped, in the same way than in IP header */
  66        struct in6_addr src;
  67        struct in6_addr dst;
  68};
  69
  70/**
  71 * struct flow_dissector_key_tipc_addrs:
  72 * @srcnode: source node address
  73 */
  74struct flow_dissector_key_tipc_addrs {
  75        __be32 srcnode;
  76};
  77
  78/**
  79 * struct flow_dissector_key_addrs:
  80 * @v4addrs: IPv4 addresses
  81 * @v6addrs: IPv6 addresses
  82 */
  83struct flow_dissector_key_addrs {
  84        union {
  85                struct flow_dissector_key_ipv4_addrs v4addrs;
  86                struct flow_dissector_key_ipv6_addrs v6addrs;
  87                struct flow_dissector_key_tipc_addrs tipcaddrs;
  88        };
  89};
  90
  91/**
  92 * flow_dissector_key_tp_ports:
  93 *      @ports: port numbers of Transport header
  94 *              src: source port number
  95 *              dst: destination port number
  96 */
  97struct flow_dissector_key_ports {
  98        union {
  99                __be32 ports;
 100                struct {
 101                        __be16 src;
 102                        __be16 dst;
 103                };
 104        };
 105};
 106
 107
 108/**
 109 * struct flow_dissector_key_eth_addrs:
 110 * @src: source Ethernet address
 111 * @dst: destination Ethernet address
 112 */
 113struct flow_dissector_key_eth_addrs {
 114        /* (dst,src) must be grouped, in the same way than in ETH header */
 115        unsigned char dst[ETH_ALEN];
 116        unsigned char src[ETH_ALEN];
 117};
 118
 119enum flow_dissector_key_id {
 120        FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
 121        FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
 122        FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
 123        FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
 124        FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
 125        FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
 126        FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */
 127        FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_flow_vlan */
 128        FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
 129        FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
 130        FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
 131
 132        FLOW_DISSECTOR_KEY_MAX,
 133};
 134
 135#define FLOW_DISSECTOR_F_PARSE_1ST_FRAG         BIT(0)
 136#define FLOW_DISSECTOR_F_STOP_AT_L3             BIT(1)
 137#define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL     BIT(2)
 138#define FLOW_DISSECTOR_F_STOP_AT_ENCAP          BIT(3)
 139
 140struct flow_dissector_key {
 141        enum flow_dissector_key_id key_id;
 142        size_t offset; /* offset of struct flow_dissector_key_*
 143                          in target the struct */
 144};
 145
 146struct flow_dissector {
 147        unsigned int used_keys; /* each bit repesents presence of one key id */
 148        unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
 149};
 150
 151struct flow_keys {
 152        struct flow_dissector_key_control control;
 153#define FLOW_KEYS_HASH_START_FIELD basic
 154        struct flow_dissector_key_basic basic;
 155        struct flow_dissector_key_tags tags;
 156        struct flow_dissector_key_vlan vlan;
 157        struct flow_dissector_key_keyid keyid;
 158        struct flow_dissector_key_ports ports;
 159        struct flow_dissector_key_addrs addrs;
 160};
 161
 162#define FLOW_KEYS_HASH_OFFSET           \
 163        offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
 164
 165__be32 flow_get_u32_src(const struct flow_keys *flow);
 166__be32 flow_get_u32_dst(const struct flow_keys *flow);
 167
 168extern struct flow_dissector flow_keys_dissector;
 169extern struct flow_dissector flow_keys_buf_dissector;
 170
 171/* struct flow_keys_digest:
 172 *
 173 * This structure is used to hold a digest of the full flow keys. This is a
 174 * larger "hash" of a flow to allow definitively matching specific flows where
 175 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
 176 * that it can by used in CB of skb (see sch_choke for an example).
 177 */
 178#define FLOW_KEYS_DIGEST_LEN    16
 179struct flow_keys_digest {
 180        u8      data[FLOW_KEYS_DIGEST_LEN];
 181};
 182
 183void make_flow_keys_digest(struct flow_keys_digest *digest,
 184                           const struct flow_keys *flow);
 185
 186static inline bool flow_keys_have_l4(const struct flow_keys *keys)
 187{
 188        return (keys->ports.ports || keys->tags.flow_label);
 189}
 190
 191u32 flow_hash_from_keys(struct flow_keys *keys);
 192
 193static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
 194                                      enum flow_dissector_key_id key_id)
 195{
 196        return flow_dissector->used_keys & (1 << key_id);
 197}
 198
 199static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
 200                                              enum flow_dissector_key_id key_id,
 201                                              void *target_container)
 202{
 203        return ((char *)target_container) + flow_dissector->offset[key_id];
 204}
 205
 206#endif
 207