text: /*
   * Copyright (c) 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at:
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #ifndef OPENVSWITCH_OFP_ACTIONS_H
  #define OPENVSWITCH_OFP_ACTIONS_H 1
  
  #include <stddef.h>
  #include <stdint.h>
  #include "openflow/openflow.h"
  #include "openflow/nicira-ext.h"
  #include "openvswitch/meta-flow.h"
  #include "openvswitch/ofp-util.h"
  #include "openvswitch/ofp-errors.h"
  #include "openvswitch/types.h"
  
  /* List of OVS abstracted actions.
   *
   * This macro is used directly only internally by this header, but the list is
   * still of interest to developers.
   *
   * Each OFPACT invocation has the following parameters:
   *
   * 1. <ENUM>, used below in the enum definition of OFPACT_<ENUM>, and
   *    elsewhere.
   *
   * 2. <STRUCT> corresponding to a structure "struct <STRUCT>", that must be
   *    defined below.  This structure must be an abstract definition of the
   *    action.  Its first member must have type "struct ofpact" and name
   *    "ofpact".  It may be fixed length or end with a flexible array member
   *    (e.g. "int member[];").
   *
   * 3. <MEMBER>, which has one of two possible values:
   *
   *        - If "struct <STRUCT>" is fixed-length, it must be "ofpact".
   *
   *        - If "struct <STRUCT>" is variable-length, it must be the name of the
   *          flexible array member.
   *
   * 4. <NAME>, a quoted string that gives the name of the action, for use in
   *    parsing actions from text.
   */
  #define OFPACTS                                                         \
      /* Output. */                                                       \
      OFPACT(OUTPUT,          ofpact_output,      ofpact, "output")       \
      OFPACT(GROUP,           ofpact_group,       ofpact, "group")        \
      OFPACT(CONTROLLER,      ofpact_controller,  userdata, "controller") \
      OFPACT(ENQUEUE,         ofpact_enqueue,     ofpact, "enqueue")      \
      OFPACT(OUTPUT_REG,      ofpact_output_reg,  ofpact, "output_reg")   \
      OFPACT(BUNDLE,          ofpact_bundle,      slaves, "bundle")       \
                                                                          \
      /* Header changes. */                                               \
      OFPACT(SET_FIELD,       ofpact_set_field,   ofpact, "set_field")    \
      OFPACT(SET_VLAN_VID,    ofpact_vlan_vid,    ofpact, "set_vlan_vid") \
      OFPACT(SET_VLAN_PCP,    ofpact_vlan_pcp,    ofpact, "set_vlan_pcp") \
      OFPACT(STRIP_VLAN,      ofpact_null,        ofpact, "strip_vlan")   \
      OFPACT(PUSH_VLAN,       ofpact_null,        ofpact, "push_vlan")    \
      OFPACT(SET_ETH_SRC,     ofpact_mac,         ofpact, "mod_dl_src")   \
      OFPACT(SET_ETH_DST,     ofpact_mac,         ofpact, "mod_dl_dst")   \
      OFPACT(SET_IPV4_SRC,    ofpact_ipv4,        ofpact, "mod_nw_src")   \
      OFPACT(SET_IPV4_DST,    ofpact_ipv4,        ofpact, "mod_nw_dst")   \
      OFPACT(SET_IP_DSCP,     ofpact_dscp,        ofpact, "mod_nw_tos")   \
      OFPACT(SET_IP_ECN,      ofpact_ecn,         ofpact, "mod_nw_ecn")   \
      OFPACT(SET_IP_TTL,      ofpact_ip_ttl,      ofpact, "mod_nw_ttl")   \
      OFPACT(SET_L4_SRC_PORT, ofpact_l4_port,     ofpact, "mod_tp_src")   \
      OFPACT(SET_L4_DST_PORT, ofpact_l4_port,     ofpact, "mod_tp_dst")   \
      OFPACT(REG_MOVE,        ofpact_reg_move,    ofpact, "move")         \
      OFPACT(STACK_PUSH,      ofpact_stack,       ofpact, "push")         \
      OFPACT(STACK_POP,       ofpact_stack,       ofpact, "pop")          \
      OFPACT(DEC_TTL,         ofpact_cnt_ids,     cnt_ids, "dec_ttl")     \
      OFPACT(SET_MPLS_LABEL,  ofpact_mpls_label,  ofpact, "set_mpls_label") \
      OFPACT(SET_MPLS_TC,     ofpact_mpls_tc,     ofpact, "set_mpls_tc")  \
      OFPACT(SET_MPLS_TTL,    ofpact_mpls_ttl,    ofpact, "set_mpls_ttl") \
      OFPACT(DEC_MPLS_TTL,    ofpact_null,        ofpact, "dec_mpls_ttl") \
      OFPACT(PUSH_MPLS,       ofpact_push_mpls,   ofpact, "push_mpls")    \
      OFPACT(POP_MPLS,        ofpact_pop_mpls,    ofpact, "pop_mpls")     \
                                                                          \
      /* Metadata. */                                                     \
      OFPACT(SET_TUNNEL,      ofpact_tunnel,      ofpact, "set_tunnel")   \
      OFPACT(SET_QUEUE,       ofpact_queue,       ofpact, "set_queue")    \
      OFPACT(POP_QUEUE,       ofpact_null,        ofpact, "pop_queue")    \
      OFPACT(FIN_TIMEOUT,     ofpact_fin_timeout, ofpact, "fin_timeout")  \
                                                                          \
      /* Flow table interaction. */                                       \
      OFPACT(RESUBMIT,        ofpact_resubmit,    ofpact, "resubmit")     \
      OFPACT(LEARN,           ofpact_learn,       specs, "learn")         \
      OFPACT(CONJUNCTION,     ofpact_conjunction, ofpact, "conjunction")  \
                                                                          \
      /* Arithmetic. */                                                   \
      OFPACT(MULTIPATH,       ofpact_multipath,   ofpact, "multipath")    \
                                                                          \
      /* Other. */                                                        \
      OFPACT(NOTE,            ofpact_note,        data, "note")           \
      OFPACT(EXIT,            ofpact_null,        ofpact, "exit")         \
      OFPACT(SAMPLE,          ofpact_sample,      ofpact, "sample")       \
      OFPACT(UNROLL_XLATE,    ofpact_unroll_xlate, ofpact, "unroll_xlate") \
      OFPACT(CT,              ofpact_conntrack,   ofpact, "ct")           \
      OFPACT(NAT,             ofpact_nat,         ofpact, "nat")          \
                                                                          \
      /* Debugging actions.                                               \
       *                                                                  \
       * These are intentionally undocumented, subject to change, and     \
       * only accepted if ovs-vswitchd is started with --enable-dummy. */ \
      OFPACT(DEBUG_RECIRC, ofpact_null,           ofpact, "debug_recirc") \
                                                                          \
      /* Instructions. */                                                 \
      OFPACT(METER,           ofpact_meter,       ofpact, "meter")        \
      OFPACT(CLEAR_ACTIONS,   ofpact_null,        ofpact, "clear_actions") \
      OFPACT(WRITE_ACTIONS,   ofpact_nest,        ofpact, "write_actions") \
      OFPACT(WRITE_METADATA,  ofpact_metadata,    ofpact, "write_metadata") \
      OFPACT(GOTO_TABLE,      ofpact_goto_table,  ofpact, "goto_table")
  
  /* enum ofpact_type, with a member OFPACT_<ENUM> for each action. */
  enum OVS_PACKED_ENUM ofpact_type {
  #define OFPACT(ENUM, STRUCT, MEMBER, NAME) OFPACT_##ENUM,
      OFPACTS
  #undef OFPACT
  };
  
  /* Define N_OFPACTS to the number of types of ofpacts. */
  enum {
  #define OFPACT(ENUM, STRUCT, MEMBER, NAME) + 1
      N_OFPACTS = OFPACTS
  #undef OFPACT
  };
  
  /* Header for an action.
   *
   * Each action is a structure "struct ofpact_*" that begins with "struct
   * ofpact", usually followed by other data that describes the action.  Actions
   * are padded out to a multiple of OFPACT_ALIGNTO bytes in length.
   *
   * The 'raw' member is special:
   *
   *     - Most "struct ofpact"s correspond to one particular kind of OpenFlow
   *       action, at least in a given OpenFlow version.  For example,
   *       OFPACT_SET_VLAN_VID corresponds to OFPAT10_SET_VLAN_VID in OpenFlow
   *       1.0.
   *
   *       For such actions, the 'raw' member is not meaningful and generally
   *       should be zero.
   *
   *     - A few "struct ofpact"s correspond to multiple OpenFlow actions.  For
   *       example, OFPACT_SET_TUNNEL can be NXAST_SET_TUNNEL or
   *       NXAST_SET_TUNNEL64.  In these cases, if the "struct ofpact" originated
   *       from OpenFlow, then we want to make sure that, if it gets translated
   *       back to OpenFlow later, it is translated back to the same action type.
   *       (Otherwise, we'd violate the promise made in DESIGN, in the "Action
   *       Reproduction" section.)
   *
   *       For such actions, the 'raw' member should be the "enum ofp_raw_action"
   *       originally extracted from the OpenFlow action.  (If the action didn't
   *       originate from OpenFlow, then setting 'raw' to zero should be fine:
   *       code to translate the ofpact to OpenFlow must tolerate this case.)
   */
  struct ofpact {
      /* We want the space advantage of an 8-bit type here on every
       * implementation, without giving up the advantage of having a useful type
       * on implementations that support packed enums. */
  #ifdef HAVE_PACKED_ENUM
      enum ofpact_type type;      /* OFPACT_*. */
  #else
      uint8_t type;               /* OFPACT_* */
  #endif
  
      uint8_t raw;                /* Original type when added, if any. */
      uint16_t len;               /* Length of the action, in bytes, including
                                   * struct ofpact, excluding padding. */
  };
  BUILD_ASSERT_DECL(sizeof(struct ofpact) == 4);
  
  /* Alignment. */
  #define OFPACT_ALIGNTO 8
  #define OFPACT_ALIGN(SIZE) ROUND_UP(SIZE, OFPACT_ALIGNTO)
  
  /* Expands to an anonymous union that contains:
   *
   *    - MEMBERS in a nested anonymous struct.
   *
   *    - An array as large as MEMBERS plus padding to a multiple of 8 bytes.
   *
   * The effect is to pad MEMBERS to a multiple of 8 bytes. */
  #define OFPACT_PADDED_MEMBERS(MEMBERS)                          \
      union {                                                     \
          struct { MEMBERS };                                     \
          uint8_t pad[OFPACT_ALIGN(sizeof(struct { MEMBERS }))];  \
      }
  
  /* Returns the ofpact following 'ofpact'. */
  static inline struct ofpact *
  ofpact_next(const struct ofpact *ofpact)
  {
      return (void *) ((uint8_t *) ofpact + OFPACT_ALIGN(ofpact->len));
  }
  
  struct ofpact *ofpact_next_flattened(const struct ofpact *);
  
  static inline struct ofpact *
  ofpact_end(const struct ofpact *ofpacts, size_t ofpacts_len)
  {
      return (void *) ((uint8_t *) ofpacts + ofpacts_len);
  }
  
  /* Assigns POS to each ofpact, in turn, in the OFPACTS_LEN bytes of ofpacts
   * starting at OFPACTS. */
  #define OFPACT_FOR_EACH(POS, OFPACTS, OFPACTS_LEN)                      \
      for ((POS) = (OFPACTS); (POS) < ofpact_end(OFPACTS, OFPACTS_LEN);  \
           (POS) = ofpact_next(POS))
  
  /* Assigns POS to each ofpact, in turn, in the OFPACTS_LEN bytes of ofpacts
   * starting at OFPACTS.
   *
   * For ofpacts that contain nested ofpacts, this visits each of the inner
   * ofpacts as well. */
  #define OFPACT_FOR_EACH_FLATTENED(POS, OFPACTS, OFPACTS_LEN)           \
      for ((POS) = (OFPACTS); (POS) < ofpact_end(OFPACTS, OFPACTS_LEN);  \
           (POS) = ofpact_next_flattened(POS))
  
  /* Action structure for each OFPACT_*. */
  
  /* OFPACT_STRIP_VLAN, OFPACT_POP_QUEUE, OFPACT_EXIT, OFPACT_CLEAR_ACTIONS.
   *
   * Used for OFPAT10_STRIP_VLAN, NXAST_POP_QUEUE, NXAST_EXIT,
   * OFPAT11_POP_VLAN, OFPIT11_CLEAR_ACTIONS.
   *
   * Action structure for actions that do not have any extra data beyond the
   * action type. */
  struct ofpact_null {
      struct ofpact ofpact;
  };
  
  /* OFPACT_OUTPUT.
   *
   * Used for OFPAT10_OUTPUT. */
  struct ofpact_output {
      struct ofpact ofpact;
      ofp_port_t port;            /* Output port. */
      uint16_t max_len;           /* Max send len, for port OFPP_CONTROLLER. */
  };
  
  /* OFPACT_CONTROLLER.
   *
   * Used for NXAST_CONTROLLER. */
  struct ofpact_controller {
      OFPACT_PADDED_MEMBERS(
          struct ofpact ofpact;
          uint16_t max_len;   /* Max length to send to controller. */
          uint16_t controller_id; /* Controller ID to send packet-in. */
          enum ofp_packet_in_reason reason; /* Reason to put in packet-in. */
  
          /* If true, this action freezes packet traversal of the OpenFlow
           * tables and adds a continuation to the packet-in message, that
           * a controller can use to resume that traversal. */
          bool pause;
  
          /* Arbitrary data to include in the packet-in message (currently,
           * only in NXT_PACKET_IN2). */
          uint16_t userdata_len;
      );
      uint8_t userdata[0];
  };
  
  /* OFPACT_ENQUEUE.
   *
   * Used for OFPAT10_ENQUEUE. */
  struct ofpact_enqueue {
      struct ofpact ofpact;
      ofp_port_t port;
      uint32_t queue;
  };
  
  /* OFPACT_OUTPUT_REG.
   *
   * Used for NXAST_OUTPUT_REG. */
  struct ofpact_output_reg {
      struct ofpact ofpact;
      uint16_t max_len;
      struct mf_subfield src;
  };
  
  /* Bundle slave choice algorithm to apply.
   *
   * In the descriptions below, 'slaves' is the list of possible slaves in the
   * order they appear in the OpenFlow action. */
  enum nx_bd_algorithm {
      /* Chooses the first live slave listed in the bundle.
       *
       * O(n_slaves) performance. */
      NX_BD_ALG_ACTIVE_BACKUP = 0,
  
      /* Highest Random Weight.
       *
       * for i in [0,n_slaves):
       *   weights[i] = hash(flow, i)
       * slave = { slaves[i] such that weights[i] >= weights[j] for all j != i }
       *
       * Redistributes 1/n_slaves of traffic when a slave's liveness changes.
       * O(n_slaves) performance.
       *
       * Uses the 'fields' and 'basis' parameters. */
      NX_BD_ALG_HRW = 1
  };
  
  /* OFPACT_BUNDLE.
   *
   * Used for NXAST_BUNDLE. */
  struct ofpact_bundle {
      struct ofpact ofpact;
  
      /* Slave choice algorithm to apply to hash value. */
      enum nx_bd_algorithm algorithm;
  
      /* What fields to hash and how. */
      enum nx_hash_fields fields;
      uint16_t basis;             /* Universal hash parameter. */
  
      struct mf_subfield dst;
  
      /* Slaves for output. */
      unsigned int n_slaves;
      ofp_port_t slaves[];
  };
  
  /* OFPACT_SET_VLAN_VID.
   *
   * We keep track if vlan was present at action validation time to avoid a
   * PUSH_VLAN when translating to OpenFlow 1.1+.
   *
   * We also keep the originating OFPUTIL action code in ofpact.compat.
   *
   * Used for OFPAT10_SET_VLAN_VID and OFPAT11_SET_VLAN_VID. */
  struct ofpact_vlan_vid {
      struct ofpact ofpact;
      uint16_t vlan_vid;          /* VLAN VID in low 12 bits, 0 in other bits. */
      bool push_vlan_if_needed;   /* OF 1.0 semantics if true. */
      bool flow_has_vlan;         /* VLAN present at action validation time? */
  };
  
  /* OFPACT_SET_VLAN_PCP.
   *
   * We keep track if vlan was present at action validation time to avoid a
   * PUSH_VLAN when translating to OpenFlow 1.1+.
   *
   * We also keep the originating OFPUTIL action code in ofpact.compat.
   *
   * Used for OFPAT10_SET_VLAN_PCP and OFPAT11_SET_VLAN_PCP. */
  struct ofpact_vlan_pcp {
      struct ofpact ofpact;
      uint8_t vlan_pcp;           /* VLAN PCP in low 3 bits, 0 in other bits. */
      bool push_vlan_if_needed;   /* OF 1.0 semantics if true. */
      bool flow_has_vlan;         /* VLAN present at action validation time? */
  };
  
  /* OFPACT_SET_ETH_SRC, OFPACT_SET_ETH_DST.
   *
   * Used for OFPAT10_SET_DL_SRC, OFPAT10_SET_DL_DST. */
  struct ofpact_mac {
      struct ofpact ofpact;
      struct eth_addr mac;
  };
  
  /* OFPACT_SET_IPV4_SRC, OFPACT_SET_IPV4_DST.
   *
   * Used for OFPAT10_SET_NW_SRC, OFPAT10_SET_NW_DST. */
  struct ofpact_ipv4 {
      struct ofpact ofpact;
      ovs_be32 ipv4;
  };
  
  /* OFPACT_SET_IP_DSCP.
   *
   * Used for OFPAT10_SET_NW_TOS. */
  struct ofpact_dscp {
      struct ofpact ofpact;
      uint8_t dscp;               /* DSCP in high 6 bits, rest ignored. */
  };
  
  /* OFPACT_SET_IP_ECN.
   *
   * Used for OFPAT11_SET_NW_ECN. */
  struct ofpact_ecn {
      struct ofpact ofpact;
      uint8_t ecn;               /* ECN in low 2 bits, rest ignored. */
  };
  
  /* OFPACT_SET_IP_TTL.
   *
   * Used for OFPAT11_SET_NW_TTL. */
  struct ofpact_ip_ttl {
      struct ofpact ofpact;
      uint8_t ttl;
  };
  
  /* OFPACT_SET_L4_SRC_PORT, OFPACT_SET_L4_DST_PORT.
   *
   * Used for OFPAT10_SET_TP_SRC, OFPAT10_SET_TP_DST. */
  struct ofpact_l4_port {
      struct ofpact ofpact;
      uint16_t port;              /* TCP, UDP or SCTP port number. */
      uint8_t  flow_ip_proto;     /* IP proto from corresponding match, or 0 */
  };
  
  /* OFPACT_REG_MOVE.
   *
   * Used for NXAST_REG_MOVE. */
  struct ofpact_reg_move {
      struct ofpact ofpact;
      struct mf_subfield src;
      struct mf_subfield dst;
  };
  
  /* OFPACT_STACK_PUSH.
   *
   * Used for NXAST_STACK_PUSH and NXAST_STACK_POP. */
  struct ofpact_stack {
      struct ofpact ofpact;
      struct mf_subfield subfield;
  };
  
  /* OFPACT_SET_FIELD.
   *
   * Used for NXAST_REG_LOAD and OFPAT12_SET_FIELD. */
  struct ofpact_set_field {
      struct ofpact ofpact;
      const struct mf_field *field;
      bool flow_has_vlan;   /* VLAN present at action validation time. */
      union mf_value value;
      union mf_value mask;
  };
  
  /* OFPACT_PUSH_VLAN/MPLS/PBB
   *
   * Used for NXAST_PUSH_MPLS, OFPAT11_PUSH_MPLS. */
  struct ofpact_push_mpls {
      struct ofpact ofpact;
      ovs_be16 ethertype;
  };
  
  /* OFPACT_POP_MPLS
   *
   * Used for NXAST_POP_MPLS, OFPAT11_POP_MPLS.. */
  struct ofpact_pop_mpls {
      struct ofpact ofpact;
      ovs_be16 ethertype;
  };
  
  /* OFPACT_SET_TUNNEL.
   *
   * Used for NXAST_SET_TUNNEL, NXAST_SET_TUNNEL64. */
  struct ofpact_tunnel {
      struct ofpact ofpact;
      uint64_t tun_id;
  };
  
  /* OFPACT_SET_QUEUE.
   *
   * Used for NXAST_SET_QUEUE. */
  struct ofpact_queue {
      struct ofpact ofpact;
      uint32_t queue_id;
  };
  
  /* OFPACT_FIN_TIMEOUT.
   *
   * Used for NXAST_FIN_TIMEOUT. */
  struct ofpact_fin_timeout {
      struct ofpact ofpact;
      uint16_t fin_idle_timeout;
      uint16_t fin_hard_timeout;
  };
  
  /* OFPACT_WRITE_METADATA.
   *
   * Used for NXAST_WRITE_METADATA. */
  struct ofpact_metadata {
      struct ofpact ofpact;
      ovs_be64 metadata;
      ovs_be64 mask;
  };
  
  /* OFPACT_METER.
   *
   * Used for OFPIT13_METER. */
  struct ofpact_meter {
      struct ofpact ofpact;
      uint32_t meter_id;
  };
  
  /* OFPACT_WRITE_ACTIONS.
   *
   * Used for OFPIT11_WRITE_ACTIONS. */
  struct ofpact_nest {
      OFPACT_PADDED_MEMBERS(struct ofpact ofpact;);
      struct ofpact actions[];
  };
  BUILD_ASSERT_DECL(offsetof(struct ofpact_nest, actions) % OFPACT_ALIGNTO == 0);
  BUILD_ASSERT_DECL(offsetof(struct ofpact_nest, actions)
                    == sizeof(struct ofpact_nest));
  
  /* Bits for 'flags' in struct nx_action_conntrack.
   *
   * If NX_CT_F_COMMIT is set, then the connection entry is moved from the
   * unconfirmed to confirmed list in the tracker. */
  enum nx_conntrack_flags {
      NX_CT_F_COMMIT = 1 << 0,
  };
  
  /* Magic value for struct nx_action_conntrack 'recirc_table' field, to specify
   * that the packet should not be recirculated. */
  #define NX_CT_RECIRC_NONE OFPTT_ALL
  
  #if !defined(IPPORT_FTP)
  #define	IPPORT_FTP  21
  #endif
  
  /* OFPACT_CT.
   *
   * Used for NXAST_CT. */
  struct ofpact_conntrack {
      OFPACT_PADDED_MEMBERS(
          struct ofpact ofpact;
          uint16_t flags;
          uint16_t zone_imm;
          struct mf_subfield zone_src;
          uint16_t alg;
          uint8_t recirc_table;
      );
      struct ofpact actions[0];
  };
  BUILD_ASSERT_DECL(offsetof(struct ofpact_conntrack, actions)
                    % OFPACT_ALIGNTO == 0);
  BUILD_ASSERT_DECL(offsetof(struct ofpact_conntrack, actions)
                    == sizeof(struct ofpact_conntrack));
  
  static inline size_t
  ofpact_ct_get_action_len(const struct ofpact_conntrack *oc)
  {
      return oc->ofpact.len - offsetof(struct ofpact_conntrack, actions);
  }
  
  static inline size_t
  ofpact_nest_get_action_len(const struct ofpact_nest *on)
  {
      return on->ofpact.len - offsetof(struct ofpact_nest, actions);
  }
  
  void ofpacts_execute_action_set(struct ofpbuf *action_list,
                                  const struct ofpbuf *action_set);
  
  /* Bits for 'flags' in struct nx_action_nat.
   */
  enum nx_nat_flags {
      NX_NAT_F_SRC          = 1 << 0,
      NX_NAT_F_DST          = 1 << 1,
      NX_NAT_F_PERSISTENT   = 1 << 2,
      NX_NAT_F_PROTO_HASH   = 1 << 3,
      NX_NAT_F_PROTO_RANDOM = 1 << 4,
  };
  
  /* OFPACT_NAT.
   *
   * Used for NXAST_NAT. */
  struct ofpact_nat {
      struct ofpact ofpact;
      uint8_t range_af; /* AF_UNSPEC, AF_INET, or AF_INET6 */
      uint16_t flags;  /* NX_NAT_F_* */
      struct {
          struct {
              uint16_t min;
              uint16_t max;
          } proto;
          union {
              struct {
                  ovs_be32 min;
                  ovs_be32 max;
              } ipv4;
              struct {
                  struct in6_addr min;
                  struct in6_addr max;
              } ipv6;
          } addr;
      } range;
  };
  
  
  /* OFPACT_RESUBMIT.
   *
   * Used for NXAST_RESUBMIT, NXAST_RESUBMIT_TABLE. */
  struct ofpact_resubmit {
      struct ofpact ofpact;
      ofp_port_t in_port;
      uint8_t table_id;
  };
  
  /* Part of struct ofpact_learn, below. */
  struct ofpact_learn_spec {
      int n_bits;                 /* Number of bits in source and dest. */
  
      int src_type;               /* One of NX_LEARN_SRC_*. */
      struct mf_subfield src;     /* NX_LEARN_SRC_FIELD only. */
      union mf_subvalue src_imm;  /* NX_LEARN_SRC_IMMEDIATE only. */
  
      int dst_type;             /* One of NX_LEARN_DST_*. */
      struct mf_subfield dst;   /* NX_LEARN_DST_MATCH, NX_LEARN_DST_LOAD only. */
  };
  
  
  /* Bits for 'flags' in struct nx_action_learn.
   *
   * If NX_LEARN_F_SEND_FLOW_REM is set, then the learned flows will have their
   * OFPFF_SEND_FLOW_REM flag set.
   *
   * If NX_LEARN_F_DELETE_LEARNED is set, then removing this action will delete
   * all the flows from the learn action's 'table_id' that have the learn
   * action's 'cookie'.  Important points:
   *
   *     - The deleted flows include those created by this action, those created
   *       by other learn actions with the same 'table_id' and 'cookie', those
   *       created by flow_mod requests by a controller in the specified table
   *       with the specified cookie, and those created through any other
   *       means.
   *
   *     - If multiple flows specify "learn" actions with
   *       NX_LEARN_F_DELETE_LEARNED with the same 'table_id' and 'cookie', then
   *       no deletion occurs until all of those "learn" actions are deleted.
   *
   *     - Deleting a flow that contains a learn action is the most obvious way
   *       to delete a learn action.  Modifying a flow's actions, or replacing it
   *       by a new flow, can also delete a learn action.  Finally, replacing a
   *       learn action with NX_LEARN_F_DELETE_LEARNED with a learn action
   *       without that flag also effectively deletes the learn action and can
   *       trigger flow deletion.
   *
   * NX_LEARN_F_DELETE_LEARNED was added in Open vSwitch 2.4. */
  enum nx_learn_flags {
      NX_LEARN_F_SEND_FLOW_REM = 1 << 0,
      NX_LEARN_F_DELETE_LEARNED = 1 << 1,
  };
  
  #define NX_LEARN_N_BITS_MASK    0x3ff
  
  #define NX_LEARN_SRC_FIELD     (0 << 13) /* Copy from field. */
  #define NX_LEARN_SRC_IMMEDIATE (1 << 13) /* Copy from immediate value. */
  #define NX_LEARN_SRC_MASK      (1 << 13)
  
  #define NX_LEARN_DST_MATCH     (0 << 11) /* Add match criterion. */
  #define NX_LEARN_DST_LOAD      (1 << 11) /* Add NXAST_REG_LOAD action. */
  #define NX_LEARN_DST_OUTPUT    (2 << 11) /* Add OFPAT_OUTPUT action. */
  #define NX_LEARN_DST_RESERVED  (3 << 11) /* Not yet defined. */
  #define NX_LEARN_DST_MASK      (3 << 11)
  
  /* OFPACT_LEARN.
   *
   * Used for NXAST_LEARN. */
  struct ofpact_learn {
      struct ofpact ofpact;
  
      uint16_t idle_timeout;      /* Idle time before discarding (seconds). */
      uint16_t hard_timeout;      /* Max time before discarding (seconds). */
      uint16_t priority;          /* Priority level of flow entry. */
      uint8_t table_id;           /* Table to insert flow entry. */
      ovs_be64 cookie;            /* Cookie for new flow. */
      enum nx_learn_flags flags;  /* NX_LEARN_F_*. */
      uint16_t fin_idle_timeout;  /* Idle timeout after FIN, if nonzero. */
      uint16_t fin_hard_timeout;  /* Hard timeout after FIN, if nonzero. */
  
      unsigned int n_specs;
      struct ofpact_learn_spec specs[];
  };
  
  /* Multipath link choice algorithm to apply.
   *
   * In the descriptions below, 'n_links' is max_link + 1. */
  enum nx_mp_algorithm {
      /* link = hash(flow) % n_links.
       *
       * Redistributes all traffic when n_links changes.  O(1) performance.  See
       * RFC 2992.
       *
       * Use UINT16_MAX for max_link to get a raw hash value. */
      NX_MP_ALG_MODULO_N = 0,
  
      /* link = hash(flow) / (MAX_HASH / n_links).
       *
       * Redistributes between one-quarter and one-half of traffic when n_links
       * changes.  O(1) performance.  See RFC 2992.
       */
      NX_MP_ALG_HASH_THRESHOLD = 1,
  
      /* Highest Random Weight.
       *
       * for i in [0,n_links):
       *   weights[i] = hash(flow, i)
       * link = { i such that weights[i] >= weights[j] for all j != i }
       *
       * Redistributes 1/n_links of traffic when n_links changes.  O(n_links)
       * performance.  If n_links is greater than a threshold (currently 64, but
       * subject to change), Open vSwitch will substitute another algorithm
       * automatically.  See RFC 2992. */
      NX_MP_ALG_HRW = 2,
  
      /* Iterative Hash.
       *
       * i = 0
       * repeat:
       *     i = i + 1
       *     link = hash(flow, i) % arg
       * while link > max_link
       *
       * Redistributes 1/n_links of traffic when n_links changes.  O(1)
       * performance when arg/max_link is bounded by a constant.
       *
       * Redistributes all traffic when arg changes.
       *
       * arg must be greater than max_link and for best performance should be no
       * more than approximately max_link * 2.  If arg is outside the acceptable
       * range, Open vSwitch will automatically substitute the least power of 2
       * greater than max_link.
       *
       * This algorithm is specific to Open vSwitch.
       */
      NX_MP_ALG_ITER_HASH = 3,
  };
  
  /* OFPACT_CONJUNCTION.
   *
   * Used for NXAST_CONJUNCTION. */
  struct ofpact_conjunction {
      struct ofpact ofpact;
      uint8_t clause;
      uint8_t n_clauses;
      uint32_t id;
  };
  
  /* OFPACT_MULTIPATH.
   *
   * Used for NXAST_MULTIPATH. */
  struct ofpact_multipath {
      struct ofpact ofpact;
  
      /* What fields to hash and how. */
      enum nx_hash_fields fields;
      uint16_t basis;             /* Universal hash parameter. */
  
      /* Multipath link choice algorithm to apply to hash value. */
      enum nx_mp_algorithm algorithm;
      uint16_t max_link;          /* Number of output links, minus 1. */
      uint32_t arg;               /* Algorithm-specific argument. */
  
      /* Where to store the result. */
      struct mf_subfield dst;
  };
  
  /* OFPACT_NOTE.
   *
   * Used for NXAST_NOTE. */
  struct ofpact_note {
      struct ofpact ofpact;
      size_t length;
      uint8_t data[];
  };
  
  /* OFPACT_SAMPLE.
   *
   * Used for NXAST_SAMPLE. */
  struct ofpact_sample {
      struct ofpact ofpact;
      uint16_t probability;  // Always >0.
      uint32_t collector_set_id;
      uint32_t obs_domain_id;
      uint32_t obs_point_id;
  };
  
  /* OFPACT_DEC_TTL.
   *
   * Used for OFPAT11_DEC_NW_TTL, NXAST_DEC_TTL and NXAST_DEC_TTL_CNT_IDS. */
  struct ofpact_cnt_ids {
      struct ofpact ofpact;
  
      /* Controller ids. */
      unsigned int n_controllers;
      uint16_t cnt_ids[];
  };
  
  /* OFPACT_SET_MPLS_LABEL.
   *
   * Used for OFPAT11_SET_MPLS_LABEL and NXAST_SET_MPLS_LABEL */
  struct ofpact_mpls_label {
      struct ofpact ofpact;
  
      ovs_be32 label;
  };
  
  /* OFPACT_SET_MPLS_TC.
   *
   * Used for OFPAT11_SET_MPLS_TC and NXAST_SET_MPLS_TC */
  struct ofpact_mpls_tc {
      struct ofpact ofpact;
  
      uint8_t tc;
  };
  
  /* OFPACT_SET_MPLS_TTL.
   *
   * Used for OFPAT11_SET_MPLS_TTL and NXAST_SET_MPLS_TTL */
  struct ofpact_mpls_ttl {
      struct ofpact ofpact;
  
      uint8_t ttl;
  };
  
  /* OFPACT_GOTO_TABLE
   *
   * Used for OFPIT11_GOTO_TABLE */
  struct ofpact_goto_table {
      struct ofpact ofpact;
      uint8_t table_id;
  };
  
  /* OFPACT_GROUP.
   *
   * Used for OFPAT11_GROUP. */
  struct ofpact_group {
      struct ofpact ofpact;
      uint32_t group_id;
  };
  
  /* OFPACT_UNROLL_XLATE.
   *
   * Used only internally. */
  struct ofpact_unroll_xlate {
      struct ofpact ofpact;
  
      /* Metadata in xlate context, visible to controller via PACKET_INs. */
      uint8_t  rule_table_id;       /* 0xFF if none. */
      ovs_be64 rule_cookie;         /* OVS_BE64_MAX if none. */
  };
  
  /* Converting OpenFlow to ofpacts. */
  enum ofperr ofpacts_pull_openflow_actions(struct ofpbuf *openflow,
                                            unsigned int actions_len,
                                            enum ofp_version version,
                                            struct ofpbuf *ofpacts);
  enum ofperr ofpacts_pull_openflow_instructions(struct ofpbuf *openflow,
                                                 unsigned int instructions_len,
                                                 enum ofp_version version,
                                                 struct ofpbuf *ofpacts);
  enum ofperr ofpacts_check(struct ofpact[], size_t ofpacts_len,
                            struct flow *, ofp_port_t max_ports,
                            uint8_t table_id, uint8_t n_tables,
                            enum ofputil_protocol *usable_protocols);
  enum ofperr ofpacts_check_consistency(struct ofpact[], size_t ofpacts_len,
                                        struct flow *, ofp_port_t max_ports,
                                        uint8_t table_id, uint8_t n_tables,
                                        enum ofputil_protocol usable_protocols);
  enum ofperr ofpact_check_output_port(ofp_port_t port, ofp_port_t max_ports);
  
  /* Converting ofpacts to OpenFlow. */
  size_t ofpacts_put_openflow_actions(const struct ofpact[], size_t ofpacts_len,
                                      struct ofpbuf *openflow, enum ofp_version);
  void ofpacts_put_openflow_instructions(const struct ofpact[],
                                         size_t ofpacts_len,
                                         struct ofpbuf *openflow,
                                         enum ofp_version ofp_version);
  
  /* Sets of supported actions. */
  ovs_be32 ofpact_bitmap_to_openflow(uint64_t ofpacts_bitmap, enum ofp_version);
  uint64_t ofpact_bitmap_from_openflow(ovs_be32 ofpat_bitmap, enum ofp_version);
  void ofpact_bitmap_format(uint64_t ofpacts_bitmap, struct ds *);
  
  /* Working with ofpacts. */
  bool ofpacts_output_to_port(const struct ofpact[], size_t ofpacts_len,
                              ofp_port_t port);
  bool ofpacts_output_to_group(const struct ofpact[], size_t ofpacts_len,
                               uint32_t group_id);
  bool ofpacts_equal(const struct ofpact a[], size_t a_len,
                     const struct ofpact b[], size_t b_len);
  const struct mf_field *ofpact_get_mf_dst(const struct ofpact *ofpact);
  uint32_t ofpacts_get_meter(const struct ofpact[], size_t ofpacts_len);
  
  /* Formatting and parsing ofpacts. */
  void ofpacts_format(const struct ofpact[], size_t ofpacts_len, struct ds *);
  char *ofpacts_parse_actions(const char *, struct ofpbuf *ofpacts,
                              enum ofputil_protocol *usable_protocols)
      OVS_WARN_UNUSED_RESULT;
  char *ofpacts_parse_instructions(const char *, struct ofpbuf *ofpacts,
                                   enum ofputil_protocol *usable_protocols)
      OVS_WARN_UNUSED_RESULT;
  const char *ofpact_name(enum ofpact_type);
  
  /* Internal use by the helpers below. */
  void ofpact_init(struct ofpact *, enum ofpact_type, size_t len);
  void *ofpact_put(struct ofpbuf *, enum ofpact_type, size_t len);
  void *ofpact_finish(struct ofpbuf *, struct ofpact *);
  
  /* For each OFPACT_<ENUM> with a corresponding struct <STRUCT>, this defines
   * the following commonly useful functions:
   *
   *   struct <STRUCT> *ofpact_put_<ENUM>(struct ofpbuf *ofpacts);
   *
   *     Appends a new 'ofpact', of length OFPACT_<ENUM>_SIZE, to 'ofpacts',
   *     initializes it with ofpact_init_<ENUM>(), and returns it.  Also sets
   *     'ofpacts->header' to the returned action.
   *
   *     After using this function to add a variable-length action, add the
   *     elements of the flexible array (e.g. with ofpbuf_put()), then use
   *     ofpact_finish() to pad the action to a multiple of OFPACT_ALIGNTO bytes
   *     and update its embedded length field.  (Keep in mind the need to refresh
   *     the structure from 'ofpacts->header' after adding data to 'ofpacts'.)
   *
   *   struct <STRUCT> *ofpact_get_<ENUM>(const struct ofpact *ofpact);
   *
   *     Returns 'ofpact' cast to "struct <STRUCT> *".  'ofpact->type' must be
   *     OFPACT_<ENUM>.
   *
   *   void ofpact_finish_<ENUM>(struct ofpbuf *ofpacts, struct <STRUCT> **ap);
   *
   *     Finishes composing variable-length action '*ap' (begun using
   *     ofpact_put_<NAME>() on 'ofpacts'), by padding the action to a multiple
   *     of OFPACT_ALIGNTO bytes and updating its embedded length field.
   *
   *     May reallocate 'ofpacts', and so as a convenience automatically updates
   *     '*ap' to point to the new location.  If the caller has other pointers
   *     within 'ap' or 'ofpacts', it needs to update them manually.
   *
   * as well as the following more rarely useful definitions:
   *
   *   void ofpact_init_<ENUM>(struct <STRUCT> *ofpact);
   *
   *     Initializes the parts of 'ofpact' that identify it as having type
   *     OFPACT_<ENUM> and length OFPACT_<ENUM>_SIZE and zeros the rest.
   *
   *   <ENUM>_SIZE
   *
   *     The size of the action structure.  For a fixed-length action, this is
   *     sizeof(struct <STRUCT>) rounded up to a multiple of OFPACT_ALIGNTO.  For
   *     a variable-length action, this is the offset to the variable-length
   *     part.
   */
  #define OFPACT(ENUM, STRUCT, MEMBER, NAME)                              \
      BUILD_ASSERT_DECL(offsetof(struct STRUCT, ofpact) == 0);            \
                                                                          \
      enum { OFPACT_##ENUM##_SIZE                                         \
             = (offsetof(struct STRUCT, MEMBER)                           \
                ? offsetof(struct STRUCT, MEMBER)                         \
                : OFPACT_ALIGN(sizeof(struct STRUCT))) };                 \
                                                                          \
      static inline struct STRUCT *                                       \
      ofpact_get_##ENUM(const struct ofpact *ofpact)                      \
      {                                                                   \
          ovs_assert(ofpact->type == OFPACT_##ENUM);                      \
          return ALIGNED_CAST(struct STRUCT *, ofpact);                   \
      }                                                                   \
                                                                          \
      static inline struct STRUCT *                                       \
      ofpact_put_##ENUM(struct ofpbuf *ofpacts)                           \
      {                                                                   \
          return ofpact_put(ofpacts, OFPACT_##ENUM,                       \
                            OFPACT_##ENUM##_SIZE);                        \
      }                                                                   \
                                                                          \
      static inline void                                                  \
      ofpact_init_##ENUM(struct STRUCT *ofpact)                           \
      {                                                                   \
          ofpact_init(&ofpact->ofpact, OFPACT_##ENUM,                     \
                      OFPACT_##ENUM##_SIZE);                              \
      }                                                                   \
                                                                          \
      static inline void                                                  \
      ofpact_finish_##ENUM(struct ofpbuf *ofpbuf, struct STRUCT **ofpactp) \
      {                                                                   \
          struct ofpact *ofpact = &(*ofpactp)->ofpact;                    \
          ovs_assert(ofpact->type == OFPACT_##ENUM);                      \
          *ofpactp = ofpact_finish(ofpbuf, ofpact);                       \
      }
  OFPACTS
  #undef OFPACT
  
  /* Additional functions for composing ofpacts. */
  struct ofpact_set_field *ofpact_put_reg_load(struct ofpbuf *ofpacts);
  
  /* OpenFlow 1.1 instructions.
   * The order is sorted in execution order. Not in the value of OFPIT11_xxx.
   * It is enforced on parser from text string.
   */
  #define OVS_INSTRUCTIONS                                    \
      DEFINE_INST(OFPIT13_METER,                              \
                  ofp13_instruction_meter,          false,    \
                  "meter")                                    \
                                                              \
      DEFINE_INST(OFPIT11_APPLY_ACTIONS,                      \
                  ofp11_instruction_actions,        true,     \
                  "apply_actions")                            \
                                                              \
      DEFINE_INST(OFPIT11_CLEAR_ACTIONS,                      \
                  ofp11_instruction,                false,    \
                  "clear_actions")                            \
                                                              \
      DEFINE_INST(OFPIT11_WRITE_ACTIONS,                      \
                  ofp11_instruction_actions,        true,     \
                  "write_actions")                            \
                                                              \
      DEFINE_INST(OFPIT11_WRITE_METADATA,                     \
                  ofp11_instruction_write_metadata, false,    \
                  "write_metadata")                           \
                                                              \
      DEFINE_INST(OFPIT11_GOTO_TABLE,                         \
                  ofp11_instruction_goto_table,     false,    \
                  "goto_table")
  
  enum ovs_instruction_type {
  #define DEFINE_INST(ENUM, STRUCT, EXTENSIBLE, NAME) OVSINST_##ENUM,
      OVS_INSTRUCTIONS
  #undef DEFINE_INST
  };
  
  enum {
  #define DEFINE_INST(ENUM, STRUCT, EXTENSIBLE, NAME) + 1
      N_OVS_INSTRUCTIONS = OVS_INSTRUCTIONS
  #undef DEFINE_INST
  };
  
  const char *ovs_instruction_name_from_type(enum ovs_instruction_type type);
  int ovs_instruction_type_from_name(const char *name);
  enum ovs_instruction_type ovs_instruction_type_from_ofpact_type(
      enum ofpact_type);
  enum ofperr ovs_instruction_type_from_inst_type(
      enum ovs_instruction_type *instruction_type, const uint16_t inst_type);
  
  ovs_be32 ovsinst_bitmap_to_openflow(uint32_t ovsinst_bitmap, enum ofp_version);
  uint32_t ovsinst_bitmap_from_openflow(ovs_be32 ofpit_bitmap,
                                        enum ofp_version);
  
  #endif /* ofp-actions.h */
  