net/openvswitch/flow.h

   1 /*
   2  * Copyright (c) 2007-2017 Nicira, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301, USA
  17  */
  18
  19 #ifndef FLOW_H
  20 #define FLOW_H 1
  21
  22 #include <linux/cache.h>
  23 #include <linux/kernel.h>
  24 #include <linux/netlink.h>
  25 #include <linux/openvswitch.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/types.h>
  28 #include <linux/rcupdate.h>
  29 #include <linux/if_ether.h>
  30 #include <linux/in6.h>
  31 #include <linux/jiffies.h>
  32 #include <linux/time.h>
  33 #include <linux/flex_array.h>
  34 #include <linux/cpumask.h>
  35 #include <net/inet_ecn.h>
  36 #include <net/ip_tunnels.h>
  37 #include <net/dst_metadata.h>
  38
  39 struct sk_buff;
  40
  41 enum sw_flow_mac_proto {
  42         MAC_PROTO_NONE = 0,
  43         MAC_PROTO_ETHERNET,
  44 };
  45 #define SW_FLOW_KEY_INVALID     0x80
  46
  47 /* Store options at the end of the array if they are less than the
  48  * maximum size. This allows us to get the benefits of variable length
  49  * matching for small options.
  50  */
  51 #define TUN_METADATA_OFFSET(opt_len) \
  52         (FIELD_SIZEOF(struct sw_flow_key, tun_opts) - opt_len)
  53 #define TUN_METADATA_OPTS(flow_key, opt_len) \
  54         ((void *)((flow_key)->tun_opts + TUN_METADATA_OFFSET(opt_len)))
  55
  56 struct ovs_tunnel_info {
  57         struct metadata_dst     *tun_dst;
  58 };
  59
  60 struct vlan_head {
  61         __be16 tpid; /* Vlan type. Generally 802.1q or 802.1ad.*/
  62         __be16 tci;  /* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
  63 };
  64
  65 #define OVS_SW_FLOW_KEY_METADATA_SIZE                   \
  66         (offsetof(struct sw_flow_key, recirc_id) +      \
  67         FIELD_SIZEOF(struct sw_flow_key, recirc_id))
  68
  69 struct sw_flow_key {
  70         u8 tun_opts[IP_TUNNEL_OPTS_MAX];
  71         u8 tun_opts_len;
  72         struct ip_tunnel_key tun_key;   /* Encapsulating tunnel key. */
  73         struct {
  74                 u32     priority;       /* Packet QoS priority. */
  75                 u32     skb_mark;       /* SKB mark. */
  76                 u16     in_port;        /* Input switch port (or DP_MAX_PORTS). */
  77         } __packed phy; /* Safe when right after 'tun_key'. */
  78         u8 mac_proto;                   /* MAC layer protocol (e.g. Ethernet). */
  79         u8 tun_proto;                   /* Protocol of encapsulating tunnel. */
  80         u32 ovs_flow_hash;              /* Datapath computed hash value.  */
  81         u32 recirc_id;                  /* Recirculation ID.  */
  82         struct {
  83                 u8     src[ETH_ALEN];   /* Ethernet source address. */
  84                 u8     dst[ETH_ALEN];   /* Ethernet destination address. */
  85                 struct vlan_head vlan;
  86                 struct vlan_head cvlan;
  87                 __be16 type;            /* Ethernet frame type. */
  88         } eth;
  89         /* Filling a hole of two bytes. */
  90         u8 ct_state;
  91         u8 ct_orig_proto;               /* CT original direction tuple IP
  92                                          * protocol.
  93                                          */
  94         union {
  95                 struct {
  96                         __be32 top_lse; /* top label stack entry */
  97                 } mpls;
  98                 struct {
  99                         u8     proto;   /* IP protocol or lower 8 bits of ARP opcode. */
 100                         u8     tos;         /* IP ToS. */
 101                         u8     ttl;         /* IP TTL/hop limit. */
 102                         u8     frag;    /* One of OVS_FRAG_TYPE_*. */
 103                 } ip;
 104         };
 105         u16 ct_zone;                    /* Conntrack zone. */
 106         struct {
 107                 __be16 src;             /* TCP/UDP/SCTP source port. */
 108                 __be16 dst;             /* TCP/UDP/SCTP destination port. */
 109                 __be16 flags;           /* TCP flags. */
 110         } tp;
 111         union {
 112                 struct {
 113                         struct {
 114                                 __be32 src;     /* IP source address. */
 115                                 __be32 dst;     /* IP destination address. */
 116                         } addr;
 117                         union {
 118                                 struct {
 119                                         __be32 src;
 120                                         __be32 dst;
 121                                 } ct_orig;      /* Conntrack original direction fields. */
 122                                 struct {
 123                                         u8 sha[ETH_ALEN];       /* ARP source hardware address. */
 124                                         u8 tha[ETH_ALEN];       /* ARP target hardware address. */
 125                                 } arp;
 126                         };
 127                 } ipv4;
 128                 struct {
 129                         struct {
 130                                 struct in6_addr src;    /* IPv6 source address. */
 131                                 struct in6_addr dst;    /* IPv6 destination address. */
 132                         } addr;
 133                         __be32 label;                   /* IPv6 flow label. */
 134                         union {
 135                                 struct {
 136                                         struct in6_addr src;
 137                                         struct in6_addr dst;
 138                                 } ct_orig;      /* Conntrack original direction fields. */
 139                                 struct {
 140                                         struct in6_addr target; /* ND target address. */
 141                                         u8 sll[ETH_ALEN];       /* ND source link layer address. */
 142                                         u8 tll[ETH_ALEN];       /* ND target link layer address. */
 143                                 } nd;
 144                         };
 145                 } ipv6;
 146         };
 147         struct {
 148                 /* Connection tracking fields not packed above. */
 149                 struct {
 150                         __be16 src;     /* CT orig tuple tp src port. */
 151                         __be16 dst;     /* CT orig tuple tp dst port. */
 152                 } orig_tp;
 153                 u32 mark;
 154                 struct ovs_key_ct_labels labels;
 155         } ct;
 156
 157 } __aligned(BITS_PER_LONG/8); /* Ensure that we can do comparisons as longs. */
 158
 159 static inline bool sw_flow_key_is_nd(const struct sw_flow_key *key)
 160 {
 161         return key->eth.type == htons(ETH_P_IPV6) &&
 162                 key->ip.proto == NEXTHDR_ICMP &&
 163                 key->tp.dst == 0 &&
 164                 (key->tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 165                  key->tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT));
 166 }
 167
 168 struct sw_flow_key_range {
 169         unsigned short int start;
 170         unsigned short int end;
 171 };
 172
 173 struct sw_flow_mask {
 174         int ref_count;
 175         struct rcu_head rcu;
 176         struct list_head list;
 177         struct sw_flow_key_range range;
 178         struct sw_flow_key key;
 179 };
 180
 181 struct sw_flow_match {
 182         struct sw_flow_key *key;
 183         struct sw_flow_key_range range;
 184         struct sw_flow_mask *mask;
 185 };
 186
 187 #define MAX_UFID_LENGTH 16 /* 128 bits */
 188
 189 struct sw_flow_id {
 190         u32 ufid_len;
 191         union {
 192                 u32 ufid[MAX_UFID_LENGTH / 4];
 193                 struct sw_flow_key *unmasked_key;
 194         };
 195 };
 196
 197 struct sw_flow_actions {
 198         struct rcu_head rcu;
 199         size_t orig_len;        /* From flow_cmd_new netlink actions size */
 200         u32 actions_len;
 201         struct nlattr actions[];
 202 };
 203
 204 struct flow_stats {
 205         u64 packet_count;               /* Number of packets matched. */
 206         u64 byte_count;                 /* Number of bytes matched. */
 207         unsigned long used;             /* Last used time (in jiffies). */
 208         spinlock_t lock;                /* Lock for atomic stats update. */
 209         __be16 tcp_flags;               /* Union of seen TCP flags. */
 210 };
 211
 212 struct sw_flow {
 213         struct rcu_head rcu;
 214         struct {
 215                 struct hlist_node node[2];
 216                 u32 hash;
 217         } flow_table, ufid_table;
 218         int stats_last_writer;          /* CPU id of the last writer on
 219                                          * 'stats[0]'.
 220                                          */
 221         struct sw_flow_key key;
 222         struct sw_flow_id id;
 223         struct cpumask cpu_used_mask;
 224         struct sw_flow_mask *mask;
 225         struct sw_flow_actions __rcu *sf_acts;
 226         struct flow_stats __rcu *stats[]; /* One for each CPU.  First one
 227                                            * is allocated at flow creation time,
 228                                            * the rest are allocated on demand
 229                                            * while holding the 'stats[0].lock'.
 230                                            */
 231 };
 232
 233 struct arp_eth_header {
 234         __be16      ar_hrd;     /* format of hardware address   */
 235         __be16      ar_pro;     /* format of protocol address   */
 236         unsigned char   ar_hln; /* length of hardware address   */
 237         unsigned char   ar_pln; /* length of protocol address   */
 238         __be16      ar_op;      /* ARP opcode (command)     */
 239
 240         /* Ethernet+IPv4 specific members. */
 241         unsigned char       ar_sha[ETH_ALEN];   /* sender hardware address  */
 242         unsigned char       ar_sip[4];          /* sender IP address        */
 243         unsigned char       ar_tha[ETH_ALEN];   /* target hardware address  */
 244         unsigned char       ar_tip[4];          /* target IP address        */
 245 } __packed;
 246
 247 static inline u8 ovs_key_mac_proto(const struct sw_flow_key *key)
 248 {
 249         return key->mac_proto & ~SW_FLOW_KEY_INVALID;
 250 }
 251
 252 static inline u16 __ovs_mac_header_len(u8 mac_proto)
 253 {
 254         return mac_proto == MAC_PROTO_ETHERNET ? ETH_HLEN : 0;
 255 }
 256
 257 static inline u16 ovs_mac_header_len(const struct sw_flow_key *key)
 258 {
 259         return __ovs_mac_header_len(ovs_key_mac_proto(key));
 260 }
 261
 262 static inline bool ovs_identifier_is_ufid(const struct sw_flow_id *sfid)
 263 {
 264         return sfid->ufid_len;
 265 }
 266
 267 static inline bool ovs_identifier_is_key(const struct sw_flow_id *sfid)
 268 {
 269         return !ovs_identifier_is_ufid(sfid);
 270 }
 271
 272 void ovs_flow_stats_update(struct sw_flow *, __be16 tcp_flags,
 273                            const struct sk_buff *);
 274 void ovs_flow_stats_get(const struct sw_flow *, struct ovs_flow_stats *,
 275                         unsigned long *used, __be16 *tcp_flags);
 276 void ovs_flow_stats_clear(struct sw_flow *);
 277 u64 ovs_flow_used_time(unsigned long flow_jiffies);
 278
 279 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key);
 280 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
 281                          struct sk_buff *skb,
 282                          struct sw_flow_key *key);
 283 /* Extract key from packet coming from userspace. */
 284 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
 285                                    struct sk_buff *skb,
 286                                    struct sw_flow_key *key, bool log);
 287
 288 #endif /* flow.h */