datapath/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 #include <net/nsh.h>
  39
  40 struct sk_buff;
  41
  42 enum sw_flow_mac_proto {
  43         MAC_PROTO_NONE = 0,
  44         MAC_PROTO_ETHERNET,
  45 };
  46 #define SW_FLOW_KEY_INVALID     0x80
  47
  48 /* Store options at the end of the array if they are less than the
  49  * maximum size. This allows us to get the benefits of variable length
  50  * matching for small options.
  51  */
  52 #define TUN_METADATA_OFFSET(opt_len) \
  53         (FIELD_SIZEOF(struct sw_flow_key, tun_opts) - opt_len)
  54 #define TUN_METADATA_OPTS(flow_key, opt_len) \
  55         ((void *)((flow_key)->tun_opts + TUN_METADATA_OFFSET(opt_len)))
  56
  57 struct ovs_tunnel_info {
  58         struct metadata_dst     *tun_dst;
  59 };
  60
  61 struct vlan_head {
  62         __be16 tpid; /* Vlan type. Generally 802.1q or 802.1ad.*/
  63         __be16 tci;  /* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
  64 };
  65
  66 #define OVS_SW_FLOW_KEY_METADATA_SIZE                   \
  67         (offsetof(struct sw_flow_key, recirc_id) +      \
  68         FIELD_SIZEOF(struct sw_flow_key, recirc_id))
  69
  70 struct ovs_key_nsh {
  71         struct ovs_nsh_key_base base;
  72         __be32 context[NSH_MD1_CONTEXT_SIZE];
  73 };
  74
  75 struct sw_flow_key {
  76         u8 tun_opts[255];
  77         u8 tun_opts_len;
  78         struct ip_tunnel_key tun_key;  /* Encapsulating tunnel key. */
  79         struct {
  80                 u32     priority;       /* Packet QoS priority. */
  81                 u32     skb_mark;       /* SKB mark. */
  82                 u16     in_port;        /* Input switch port (or DP_MAX_PORTS). */
  83         } __packed phy; /* Safe when right after 'tun_key'. */
  84         u8 mac_proto;                   /* MAC layer protocol (e.g. Ethernet). */
  85         u8 tun_proto;                   /* Protocol of encapsulating tunnel. */
  86         u32 ovs_flow_hash;              /* Datapath computed hash value.  */
  87         u32 recirc_id;                  /* Recirculation ID.  */
  88         struct {
  89                 u8     src[ETH_ALEN];   /* Ethernet source address. */
  90                 u8     dst[ETH_ALEN];   /* Ethernet destination address. */
  91                 struct vlan_head vlan;
  92                 struct vlan_head cvlan;
  93                 __be16 type;            /* Ethernet frame type. */
  94         } eth;
  95         /* Filling a hole of two bytes. */
  96         u8 ct_state;
  97         u8 ct_orig_proto;               /* CT original direction tuple IP
  98                                          * protocol.
  99                                          */
 100         union {
 101                 struct {
 102                         __be32 top_lse; /* top label stack entry */
 103                 } mpls;
 104                 struct {
 105                         u8     proto;   /* IP protocol or lower 8 bits of ARP opcode. */
 106                         u8     tos;         /* IP ToS. */
 107                         u8     ttl;         /* IP TTL/hop limit. */
 108                         u8     frag;    /* One of OVS_FRAG_TYPE_*. */
 109                 } ip;
 110         };
 111         u16 ct_zone;                    /* Conntrack zone. */
 112         struct {
 113                 __be16 src;             /* TCP/UDP/SCTP source port. */
 114                 __be16 dst;             /* TCP/UDP/SCTP destination port. */
 115                 __be16 flags;           /* TCP flags. */
 116         } tp;
 117         union {
 118                 struct {
 119                         struct {
 120                                 __be32 src;     /* IP source address. */
 121                                 __be32 dst;     /* IP destination address. */
 122                         } addr;
 123                         union {
 124                                 struct {
 125                                         __be32 src;
 126                                         __be32 dst;
 127                                 } ct_orig;      /* Conntrack original direction fields. */
 128                                 struct {
 129                                         u8 sha[ETH_ALEN];       /* ARP source hardware address. */
 130                                         u8 tha[ETH_ALEN];       /* ARP target hardware address. */
 131                                 } arp;
 132                         };
 133                 } ipv4;
 134                 struct {
 135                         struct {
 136                                 struct in6_addr src;    /* IPv6 source address. */
 137                                 struct in6_addr dst;    /* IPv6 destination address. */
 138                         } addr;
 139                         __be32 label;                   /* IPv6 flow label. */
 140                         union {
 141                                 struct {
 142                                         struct in6_addr src;
 143                                         struct in6_addr dst;
 144                                 } ct_orig;      /* Conntrack original direction fields. */
 145                                 struct {
 146                                         struct in6_addr target; /* ND target address. */
 147                                         u8 sll[ETH_ALEN];       /* ND source link layer address. */
 148                                         u8 tll[ETH_ALEN];       /* ND target link layer address. */
 149                                 } nd;
 150                         };
 151                 } ipv6;
 152                 struct ovs_key_nsh nsh;         /* network service header */
 153         };
 154         struct {
 155                 /* Connection tracking fields not packed above. */
 156                 struct {
 157                         __be16 src;     /* CT orig tuple tp src port. */
 158                         __be16 dst;     /* CT orig tuple tp dst port. */
 159                 } orig_tp;
 160                 u32 mark;
 161                 struct ovs_key_ct_labels labels;
 162         } ct;
 163
 164 } __aligned(BITS_PER_LONG/8); /* Ensure that we can do comparisons as longs. */
 165
 166 static inline bool sw_flow_key_is_nd(const struct sw_flow_key *key)
 167 {
 168         return key->eth.type == htons(ETH_P_IPV6) &&
 169                 key->ip.proto == NEXTHDR_ICMP &&
 170                 key->tp.dst == 0 &&
 171                 (key->tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 172                  key->tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT));
 173 }
 174
 175 struct sw_flow_key_range {
 176         unsigned short int start;
 177         unsigned short int end;
 178 };
 179
 180 struct sw_flow_mask {
 181         int ref_count;
 182         struct rcu_head rcu;
 183         struct sw_flow_key_range range;
 184         struct sw_flow_key key;
 185 };
 186
 187 struct sw_flow_match {
 188         struct sw_flow_key *key;
 189         struct sw_flow_key_range range;
 190         struct sw_flow_mask *mask;
 191 };
 192
 193 #define MAX_UFID_LENGTH 16 /* 128 bits */
 194
 195 struct sw_flow_id {
 196         u32 ufid_len;
 197         union {
 198                 u32 ufid[MAX_UFID_LENGTH / 4];
 199                 struct sw_flow_key *unmasked_key;
 200         };
 201 };
 202
 203 struct sw_flow_actions {
 204         struct rcu_head rcu;
 205         size_t orig_len;        /* From flow_cmd_new netlink actions size */
 206         u32 actions_len;
 207         struct nlattr actions[];
 208 };
 209
 210 struct flow_stats {
 211         u64 packet_count;               /* Number of packets matched. */
 212         u64 byte_count;                 /* Number of bytes matched. */
 213         unsigned long used;             /* Last used time (in jiffies). */
 214         spinlock_t lock;                /* Lock for atomic stats update. */
 215         __be16 tcp_flags;               /* Union of seen TCP flags. */
 216 };
 217
 218 struct sw_flow {
 219         struct rcu_head rcu;
 220         struct {
 221                 struct hlist_node node[2];
 222                 u32 hash;
 223         } flow_table, ufid_table;
 224         int stats_last_writer;          /* CPU id of the last writer on
 225                                          * 'stats[0]'.
 226                                          */
 227         struct sw_flow_key key;
 228         struct sw_flow_id id;
 229         struct cpumask cpu_used_mask;
 230         struct sw_flow_mask *mask;
 231         struct sw_flow_actions __rcu *sf_acts;
 232         struct flow_stats __rcu *stats[]; /* One for each CPU.  First one
 233                                            * is allocated at flow creation time,
 234                                            * the rest are allocated on demand
 235                                            * while holding the 'stats[0].lock'.
 236                                            */
 237 };
 238
 239 struct arp_eth_header {
 240         __be16      ar_hrd;     /* format of hardware address   */
 241         __be16      ar_pro;     /* format of protocol address   */
 242         unsigned char   ar_hln; /* length of hardware address   */
 243         unsigned char   ar_pln; /* length of protocol address   */
 244         __be16      ar_op;      /* ARP opcode (command)     */
 245
 246         /* Ethernet+IPv4 specific members. */
 247         unsigned char       ar_sha[ETH_ALEN];   /* sender hardware address  */
 248         unsigned char       ar_sip[4];          /* sender IP address        */
 249         unsigned char       ar_tha[ETH_ALEN];   /* target hardware address  */
 250         unsigned char       ar_tip[4];          /* target IP address        */
 251 } __packed;
 252
 253 static inline u8 ovs_key_mac_proto(const struct sw_flow_key *key)
 254 {
 255         return key->mac_proto & ~SW_FLOW_KEY_INVALID;
 256 }
 257
 258 static inline u16 __ovs_mac_header_len(u8 mac_proto)
 259 {
 260         return mac_proto == MAC_PROTO_ETHERNET ? ETH_HLEN : 0;
 261 }
 262
 263 static inline u16 ovs_mac_header_len(const struct sw_flow_key *key)
 264 {
 265         return __ovs_mac_header_len(ovs_key_mac_proto(key));
 266 }
 267
 268 static inline bool ovs_identifier_is_ufid(const struct sw_flow_id *sfid)
 269 {
 270         return sfid->ufid_len;
 271 }
 272
 273 static inline bool ovs_identifier_is_key(const struct sw_flow_id *sfid)
 274 {
 275         return !ovs_identifier_is_ufid(sfid);
 276 }
 277
 278 void ovs_flow_stats_update(struct sw_flow *, __be16 tcp_flags,
 279                            const struct sk_buff *);
 280 void ovs_flow_stats_get(const struct sw_flow *, struct ovs_flow_stats *,
 281                         unsigned long *used, __be16 *tcp_flags);
 282 void ovs_flow_stats_clear(struct sw_flow *);
 283 u64 ovs_flow_used_time(unsigned long flow_jiffies);
 284
 285 /* Update the non-metadata part of the flow key using skb. */
 286 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key);
 287 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
 288                          struct sk_buff *skb,
 289                          struct sw_flow_key *key);
 290 /* Extract key from packet coming from userspace. */
 291 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
 292                                    struct sk_buff *skb,
 293                                    struct sw_flow_key *key, bool log);
 294
 295 #endif /* flow.h */