include/net/flow_dissector.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _NET_FLOW_DISSECTOR_H
   3 #define _NET_FLOW_DISSECTOR_H
   4
   5 #include <linux/types.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         u32     flags;
  17 };
  18
  19 #define FLOW_DIS_IS_FRAGMENT    BIT(0)
  20 #define FLOW_DIS_FIRST_FRAG     BIT(1)
  21 #define FLOW_DIS_ENCAPSULATION  BIT(2)
  22
  23 enum flow_dissect_ret {
  24         FLOW_DISSECT_RET_OUT_GOOD,
  25         FLOW_DISSECT_RET_OUT_BAD,
  26         FLOW_DISSECT_RET_PROTO_AGAIN,
  27         FLOW_DISSECT_RET_IPPROTO_AGAIN,
  28         FLOW_DISSECT_RET_CONTINUE,
  29 };
  30
  31 /**
  32  * struct flow_dissector_key_basic:
  33  * @thoff: Transport header offset
  34  * @n_proto: Network header protocol (eg. IPv4/IPv6)
  35  * @ip_proto: Transport header protocol (eg. TCP/UDP)
  36  */
  37 struct flow_dissector_key_basic {
  38         __be16  n_proto;
  39         u8      ip_proto;
  40         u8      padding;
  41 };
  42
  43 struct flow_dissector_key_tags {
  44         u32     flow_label;
  45 };
  46
  47 struct flow_dissector_key_vlan {
  48         u16     vlan_id:12,
  49                 vlan_dei:1,
  50                 vlan_priority:3;
  51         __be16  vlan_tpid;
  52 };
  53
  54 struct flow_dissector_key_mpls {
  55         u32     mpls_ttl:8,
  56                 mpls_bos:1,
  57                 mpls_tc:3,
  58                 mpls_label:20;
  59 };
  60
  61 #define FLOW_DIS_TUN_OPTS_MAX 255
  62 /**
  63  * struct flow_dissector_key_enc_opts:
  64  * @data: tunnel option data
  65  * @len: length of tunnel option data
  66  * @dst_opt_type: tunnel option type
  67  */
  68 struct flow_dissector_key_enc_opts {
  69         u8 data[FLOW_DIS_TUN_OPTS_MAX]; /* Using IP_TUNNEL_OPTS_MAX is desired
  70                                          * here but seems difficult to #include
  71                                          */
  72         u8 len;
  73         __be16 dst_opt_type;
  74 };
  75
  76 struct flow_dissector_key_keyid {
  77         __be32  keyid;
  78 };
  79
  80 /**
  81  * struct flow_dissector_key_ipv4_addrs:
  82  * @src: source ip address
  83  * @dst: destination ip address
  84  */
  85 struct flow_dissector_key_ipv4_addrs {
  86         /* (src,dst) must be grouped, in the same way than in IP header */
  87         __be32 src;
  88         __be32 dst;
  89 };
  90
  91 /**
  92  * struct flow_dissector_key_ipv6_addrs:
  93  * @src: source ip address
  94  * @dst: destination ip address
  95  */
  96 struct flow_dissector_key_ipv6_addrs {
  97         /* (src,dst) must be grouped, in the same way than in IP header */
  98         struct in6_addr src;
  99         struct in6_addr dst;
 100 };
 101
 102 /**
 103  * struct flow_dissector_key_tipc:
 104  * @key: source node address combined with selector
 105  */
 106 struct flow_dissector_key_tipc {
 107         __be32 key;
 108 };
 109
 110 /**
 111  * struct flow_dissector_key_addrs:
 112  * @v4addrs: IPv4 addresses
 113  * @v6addrs: IPv6 addresses
 114  */
 115 struct flow_dissector_key_addrs {
 116         union {
 117                 struct flow_dissector_key_ipv4_addrs v4addrs;
 118                 struct flow_dissector_key_ipv6_addrs v6addrs;
 119                 struct flow_dissector_key_tipc tipckey;
 120         };
 121 };
 122
 123 /**
 124  * flow_dissector_key_arp:
 125  *      @ports: Operation, source and target addresses for an ARP header
 126  *              for Ethernet hardware addresses and IPv4 protocol addresses
 127  *              sip: Sender IP address
 128  *              tip: Target IP address
 129  *              op:  Operation
 130  *              sha: Sender hardware address
 131  *              tpa: Target hardware address
 132  */
 133 struct flow_dissector_key_arp {
 134         __u32 sip;
 135         __u32 tip;
 136         __u8 op;
 137         unsigned char sha[ETH_ALEN];
 138         unsigned char tha[ETH_ALEN];
 139 };
 140
 141 /**
 142  * flow_dissector_key_tp_ports:
 143  *      @ports: port numbers of Transport header
 144  *              src: source port number
 145  *              dst: destination port number
 146  */
 147 struct flow_dissector_key_ports {
 148         union {
 149                 __be32 ports;
 150                 struct {
 151                         __be16 src;
 152                         __be16 dst;
 153                 };
 154         };
 155 };
 156
 157 /**
 158  * flow_dissector_key_icmp:
 159  *      @ports: type and code of ICMP header
 160  *              icmp: ICMP type (high) and code (low)
 161  *              type: ICMP type
 162  *              code: ICMP code
 163  */
 164 struct flow_dissector_key_icmp {
 165         union {
 166                 __be16 icmp;
 167                 struct {
 168                         u8 type;
 169                         u8 code;
 170                 };
 171         };
 172 };
 173
 174 /**
 175  * struct flow_dissector_key_eth_addrs:
 176  * @src: source Ethernet address
 177  * @dst: destination Ethernet address
 178  */
 179 struct flow_dissector_key_eth_addrs {
 180         /* (dst,src) must be grouped, in the same way than in ETH header */
 181         unsigned char dst[ETH_ALEN];
 182         unsigned char src[ETH_ALEN];
 183 };
 184
 185 /**
 186  * struct flow_dissector_key_tcp:
 187  * @flags: flags
 188  */
 189 struct flow_dissector_key_tcp {
 190         __be16 flags;
 191 };
 192
 193 /**
 194  * struct flow_dissector_key_ip:
 195  * @tos: tos
 196  * @ttl: ttl
 197  */
 198 struct flow_dissector_key_ip {
 199         __u8    tos;
 200         __u8    ttl;
 201 };
 202
 203 /**
 204  * struct flow_dissector_key_meta:
 205  * @ingress_ifindex: ingress ifindex
 206  */
 207 struct flow_dissector_key_meta {
 208         int ingress_ifindex;
 209 };
 210
 211 /**
 212  * struct flow_dissector_key_ct:
 213  * @ct_state: conntrack state after converting with map
 214  * @ct_mark: conttrack mark
 215  * @ct_zone: conntrack zone
 216  * @ct_labels: conntrack labels
 217  */
 218 struct flow_dissector_key_ct {
 219         u16     ct_state;
 220         u16     ct_zone;
 221         u32     ct_mark;
 222         u32     ct_labels[4];
 223 };
 224
 225 enum flow_dissector_key_id {
 226         FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
 227         FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
 228         FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
 229         FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
 230         FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
 231         FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
 232         FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
 233         FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
 234         FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
 235         FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
 236         FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
 237         FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
 238         FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
 239         FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
 240         FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
 241         FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
 242         FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
 243         FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
 244         FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
 245         FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
 246         FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
 247         FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
 248         FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
 249         FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
 250         FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
 251         FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
 252
 253         FLOW_DISSECTOR_KEY_MAX,
 254 };
 255
 256 #define FLOW_DISSECTOR_F_PARSE_1ST_FRAG         BIT(0)
 257 #define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL     BIT(1)
 258 #define FLOW_DISSECTOR_F_STOP_AT_ENCAP          BIT(2)
 259
 260 struct flow_dissector_key {
 261         enum flow_dissector_key_id key_id;
 262         size_t offset; /* offset of struct flow_dissector_key_*
 263                           in target the struct */
 264 };
 265
 266 struct flow_dissector {
 267         unsigned int used_keys; /* each bit repesents presence of one key id */
 268         unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
 269 };
 270
 271 struct flow_keys_basic {
 272         struct flow_dissector_key_control control;
 273         struct flow_dissector_key_basic basic;
 274 };
 275
 276 struct flow_keys {
 277         struct flow_dissector_key_control control;
 278 #define FLOW_KEYS_HASH_START_FIELD basic
 279         struct flow_dissector_key_basic basic;
 280         struct flow_dissector_key_tags tags;
 281         struct flow_dissector_key_vlan vlan;
 282         struct flow_dissector_key_vlan cvlan;
 283         struct flow_dissector_key_keyid keyid;
 284         struct flow_dissector_key_ports ports;
 285         struct flow_dissector_key_addrs addrs;
 286 };
 287
 288 #define FLOW_KEYS_HASH_OFFSET           \
 289         offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
 290
 291 __be32 flow_get_u32_src(const struct flow_keys *flow);
 292 __be32 flow_get_u32_dst(const struct flow_keys *flow);
 293
 294 extern struct flow_dissector flow_keys_dissector;
 295 extern struct flow_dissector flow_keys_basic_dissector;
 296
 297 /* struct flow_keys_digest:
 298  *
 299  * This structure is used to hold a digest of the full flow keys. This is a
 300  * larger "hash" of a flow to allow definitively matching specific flows where
 301  * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
 302  * that it can be used in CB of skb (see sch_choke for an example).
 303  */
 304 #define FLOW_KEYS_DIGEST_LEN    16
 305 struct flow_keys_digest {
 306         u8      data[FLOW_KEYS_DIGEST_LEN];
 307 };
 308
 309 void make_flow_keys_digest(struct flow_keys_digest *digest,
 310                            const struct flow_keys *flow);
 311
 312 static inline bool flow_keys_have_l4(const struct flow_keys *keys)
 313 {
 314         return (keys->ports.ports || keys->tags.flow_label);
 315 }
 316
 317 u32 flow_hash_from_keys(struct flow_keys *keys);
 318
 319 static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
 320                                       enum flow_dissector_key_id key_id)
 321 {
 322         return flow_dissector->used_keys & (1 << key_id);
 323 }
 324
 325 static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
 326                                               enum flow_dissector_key_id key_id,
 327                                               void *target_container)
 328 {
 329         return ((char *)target_container) + flow_dissector->offset[key_id];
 330 }
 331
 332 struct bpf_flow_dissector {
 333         struct bpf_flow_keys    *flow_keys;
 334         const struct sk_buff    *skb;
 335         void                    *data;
 336         void                    *data_end;
 337 };
 338
 339 #endif