text: /*
   * Copyright (c) 2011-2017 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.
   */
  
  #include <config.h>
  
  #include "openvswitch/meta-flow.h"
  
  #include <errno.h>
  #include <limits.h>
  #include <netinet/icmp6.h>
  #include <netinet/ip6.h>
  
  #include "classifier.h"
  #include "openvswitch/dynamic-string.h"
  #include "nx-match.h"
  #include "ovs-atomic.h"
  #include "ovs-rcu.h"
  #include "ovs-thread.h"
  #include "packets.h"
  #include "random.h"
  #include "openvswitch/shash.h"
  #include "socket-util.h"
  #include "tun-metadata.h"
  #include "unaligned.h"
  #include "util.h"
  #include "openvswitch/ofp-errors.h"
  #include "openvswitch/ofp-match.h"
  #include "openvswitch/ofp-port.h"
  #include "openvswitch/vlog.h"
  #include "vl-mff-map.h"
  #include "openvswitch/nsh.h"
  
  VLOG_DEFINE_THIS_MODULE(meta_flow);
  
  #define FLOW_U32OFS(FIELD)                                              \
      offsetof(struct flow, FIELD) % 4 ? -1 : offsetof(struct flow, FIELD) / 4
  
  #define MF_FIELD_SIZES(MEMBER)                  \
      sizeof ((union mf_value *)0)->MEMBER,       \
      8 * sizeof ((union mf_value *)0)->MEMBER
  
  extern const struct mf_field mf_fields[MFF_N_IDS]; /* Silence a warning. */
  
  const struct mf_field mf_fields[MFF_N_IDS] = {
  #include "meta-flow.inc"
  };
  
  /* Maps from an mf_field's 'name' or 'extra_name' to the mf_field. */
  static struct shash mf_by_name;
  
  /* Rate limit for parse errors.  These always indicate a bug in an OpenFlow
   * controller and so there's not much point in showing a lot of them. */
  static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
  
  #define MF_VALUE_EXACT_8 0xff, 0xff, 0xff, 0xff,  0xff, 0xff, 0xff, 0xff
  #define MF_VALUE_EXACT_16 MF_VALUE_EXACT_8, MF_VALUE_EXACT_8
  #define MF_VALUE_EXACT_32 MF_VALUE_EXACT_16, MF_VALUE_EXACT_16
  #define MF_VALUE_EXACT_64 MF_VALUE_EXACT_32, MF_VALUE_EXACT_32
  #define MF_VALUE_EXACT_128 MF_VALUE_EXACT_64, MF_VALUE_EXACT_64
  #define MF_VALUE_EXACT_INITIALIZER { .tun_metadata = { MF_VALUE_EXACT_128 } }
  
  const union mf_value exact_match_mask = MF_VALUE_EXACT_INITIALIZER;
  
  static void nxm_init(void);
  
  /* Returns the field with the given 'name', or a null pointer if no field has
   * that name. */
  const struct mf_field *
  mf_from_name(const char *name)
  {
      nxm_init();
      return shash_find_data(&mf_by_name, name);
  }
  
  /* Returns the field with the given 'name' (which is 'len' bytes long), or a
   * null pointer if no field has that name. */
  const struct mf_field *
  mf_from_name_len(const char *name, size_t len)
  {
      nxm_init();
  
      struct shash_node *node = shash_find_len(&mf_by_name, name, len);
      return node ? node->data : NULL;
  }
  
  static void
  nxm_do_init(void)
  {
      int i;
  
      shash_init(&mf_by_name);
      for (i = 0; i < MFF_N_IDS; i++) {
          const struct mf_field *mf = &mf_fields[i];
  
          ovs_assert(mf->id == i); /* Fields must be in the enum order. */
  
          shash_add_once(&mf_by_name, mf->name, mf);
          if (mf->extra_name) {
              shash_add_once(&mf_by_name, mf->extra_name, mf);
          }
      }
  }
  
  static void
  nxm_init(void)
  {
      static pthread_once_t once = PTHREAD_ONCE_INIT;
      pthread_once(&once, nxm_do_init);
  }
  
  /* Consider the two value/mask pairs 'a_value/a_mask' and 'b_value/b_mask' as
   * restrictions on a field's value.  Then, this function initializes
   * 'dst_value/dst_mask' such that it combines the restrictions of both pairs.
   * This is not always possible, i.e. if one pair insists on a value of 0 in
   * some bit and the other pair insists on a value of 1 in that bit.  This
   * function returns false in a case where the combined restriction is
   * impossible (in which case 'dst_value/dst_mask' is not fully initialized),
   * true otherwise.
   *
   * (As usually true for value/mask pairs in OVS, any 1-bit in a value must have
   * a corresponding 1-bit in its mask.) */
  bool
  mf_subvalue_intersect(const union mf_subvalue *a_value,
                        const union mf_subvalue *a_mask,
                        const union mf_subvalue *b_value,
                        const union mf_subvalue *b_mask,
                        union mf_subvalue *dst_value,
                        union mf_subvalue *dst_mask)
  {
      for (int i = 0; i < ARRAY_SIZE(a_value->be64); i++) {
          ovs_be64 av = a_value->be64[i];
          ovs_be64 am = a_mask->be64[i];
          ovs_be64 bv = b_value->be64[i];
          ovs_be64 bm = b_mask->be64[i];
          ovs_be64 *dv = &dst_value->be64[i];
          ovs_be64 *dm = &dst_mask->be64[i];
  
          if ((av ^ bv) & (am & bm)) {
              return false;
          }
          *dv = av | bv;
          *dm = am | bm;
      }
      return true;
  }
  
  /* Returns the "number of bits" in 'v', e.g. 1 if only the lowest-order bit is
   * set, 2 if the second-lowest-order bit is set, and so on. */
  int
  mf_subvalue_width(const union mf_subvalue *v)
  {
      return 1 + bitwise_rscan(v, sizeof *v, true, sizeof *v * 8 - 1, -1);
  }
  
  /* For positive 'n', shifts the bits in 'value' 'n' bits to the left, and for
   * negative 'n', shifts the bits '-n' bits to the right. */
  void
  mf_subvalue_shift(union mf_subvalue *value, int n)
  {
      if (n) {
          union mf_subvalue tmp;
          memset(&tmp, 0, sizeof tmp);
  
          if (n > 0 && n < 8 * sizeof tmp) {
              bitwise_copy(value, sizeof *value, 0,
                           &tmp, sizeof tmp, n,
                           8 * sizeof tmp - n);
          } else if (n < 0 && n > -8 * sizeof tmp) {
              bitwise_copy(value, sizeof *value, -n,
                           &tmp, sizeof tmp, 0,
                           8 * sizeof tmp + n);
          }
          *value = tmp;
      }
  }
  
  /* Appends a formatted representation of 'sv' to 's'. */
  void
  mf_subvalue_format(const union mf_subvalue *sv, struct ds *s)
  {
      ds_put_hex(s, sv, sizeof *sv);
  }
  
  /* Returns true if 'wc' wildcards all the bits in field 'mf', false if 'wc'
   * specifies at least one bit in the field.
   *
   * The caller is responsible for ensuring that 'wc' corresponds to a flow that
   * meets 'mf''s prerequisites. */
  bool
  mf_is_all_wild(const struct mf_field *mf, const struct flow_wildcards *wc)
  {
      switch (mf->id) {
      case MFF_DP_HASH:
          return !wc->masks.dp_hash;
      case MFF_RECIRC_ID:
          return !wc->masks.recirc_id;
      case MFF_PACKET_TYPE:
          return !wc->masks.packet_type;
      case MFF_CONJ_ID:
          return !wc->masks.conj_id;
      case MFF_TUN_SRC:
          return !wc->masks.tunnel.ip_src;
      case MFF_TUN_DST:
          return !wc->masks.tunnel.ip_dst;
      case MFF_TUN_IPV6_SRC:
          return ipv6_mask_is_any(&wc->masks.tunnel.ipv6_src);
      case MFF_TUN_IPV6_DST:
          return ipv6_mask_is_any(&wc->masks.tunnel.ipv6_dst);
      case MFF_TUN_ID:
          return !wc->masks.tunnel.tun_id;
      case MFF_TUN_TOS:
          return !wc->masks.tunnel.ip_tos;
      case MFF_TUN_TTL:
          return !wc->masks.tunnel.ip_ttl;
      case MFF_TUN_FLAGS:
          return !(wc->masks.tunnel.flags & FLOW_TNL_PUB_F_MASK);
      case MFF_TUN_GBP_ID:
          return !wc->masks.tunnel.gbp_id;
      case MFF_TUN_GBP_FLAGS:
          return !wc->masks.tunnel.gbp_flags;
      case MFF_TUN_ERSPAN_VER:
          return !wc->masks.tunnel.erspan_ver;
      case MFF_TUN_ERSPAN_IDX:
          return !wc->masks.tunnel.erspan_idx;
      case MFF_TUN_ERSPAN_DIR:
          return !wc->masks.tunnel.erspan_dir;
      case MFF_TUN_ERSPAN_HWID:
          return !wc->masks.tunnel.erspan_hwid;
      CASE_MFF_TUN_METADATA:
          return !ULLONG_GET(wc->masks.tunnel.metadata.present.map,
                             mf->id - MFF_TUN_METADATA0);
      case MFF_METADATA:
          return !wc->masks.metadata;
      case MFF_IN_PORT:
      case MFF_IN_PORT_OXM:
          return !wc->masks.in_port.ofp_port;
      case MFF_SKB_PRIORITY:
          return !wc->masks.skb_priority;
      case MFF_PKT_MARK:
          return !wc->masks.pkt_mark;
      case MFF_CT_STATE:
          return !wc->masks.ct_state;
      case MFF_CT_ZONE:
          return !wc->masks.ct_zone;
      case MFF_CT_MARK:
          return !wc->masks.ct_mark;
      case MFF_CT_LABEL:
          return ovs_u128_is_zero(wc->masks.ct_label);
      case MFF_CT_NW_PROTO:
          return !wc->masks.ct_nw_proto;
      case MFF_CT_NW_SRC:
          return !wc->masks.ct_nw_src;
      case MFF_CT_NW_DST:
          return !wc->masks.ct_nw_dst;
      case MFF_CT_TP_SRC:
          return !wc->masks.ct_tp_src;
      case MFF_CT_TP_DST:
          return !wc->masks.ct_tp_dst;
      case MFF_CT_IPV6_SRC:
          return ipv6_mask_is_any(&wc->masks.ct_ipv6_src);
      case MFF_CT_IPV6_DST:
          return ipv6_mask_is_any(&wc->masks.ct_ipv6_dst);
      CASE_MFF_REGS:
          return !wc->masks.regs[mf->id - MFF_REG0];
      CASE_MFF_XREGS:
          return !flow_get_xreg(&wc->masks, mf->id - MFF_XREG0);
      CASE_MFF_XXREGS: {
          ovs_u128 value = flow_get_xxreg(&wc->masks, mf->id - MFF_XXREG0);
          return ovs_u128_is_zero(value);
      }
      case MFF_ACTSET_OUTPUT:
          return !wc->masks.actset_output;
  
      case MFF_ETH_SRC:
          return eth_addr_is_zero(wc->masks.dl_src);
      case MFF_ETH_DST:
          return eth_addr_is_zero(wc->masks.dl_dst);
      case MFF_ETH_TYPE:
          return !wc->masks.dl_type;
  
      case MFF_ARP_SHA:
      case MFF_ND_SLL:
          return eth_addr_is_zero(wc->masks.arp_sha);
  
      case MFF_ARP_THA:
      case MFF_ND_TLL:
          return eth_addr_is_zero(wc->masks.arp_tha);
  
      case MFF_VLAN_TCI:
          return !wc->masks.vlans[0].tci;
      case MFF_DL_VLAN:
          return !(wc->masks.vlans[0].tci & htons(VLAN_VID_MASK));
      case MFF_VLAN_VID:
          return !(wc->masks.vlans[0].tci & htons(VLAN_VID_MASK | VLAN_CFI));
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
          return !(wc->masks.vlans[0].tci & htons(VLAN_PCP_MASK));
  
      case MFF_MPLS_LABEL:
          return !(wc->masks.mpls_lse[0] & htonl(MPLS_LABEL_MASK));
      case MFF_MPLS_TC:
          return !(wc->masks.mpls_lse[0] & htonl(MPLS_TC_MASK));
      case MFF_MPLS_BOS:
          return !(wc->masks.mpls_lse[0] & htonl(MPLS_BOS_MASK));
      case MFF_MPLS_TTL:
          return !(wc->masks.mpls_lse[0] & htonl(MPLS_TTL_MASK));
  
      case MFF_IPV4_SRC:
          return !wc->masks.nw_src;
      case MFF_IPV4_DST:
          return !wc->masks.nw_dst;
  
      case MFF_IPV6_SRC:
          return ipv6_mask_is_any(&wc->masks.ipv6_src);
      case MFF_IPV6_DST:
          return ipv6_mask_is_any(&wc->masks.ipv6_dst);
  
      case MFF_IPV6_LABEL:
          return !wc->masks.ipv6_label;
  
      case MFF_IP_PROTO:
          return !wc->masks.nw_proto;
      case MFF_IP_DSCP:
      case MFF_IP_DSCP_SHIFTED:
          return !(wc->masks.nw_tos & IP_DSCP_MASK);
      case MFF_IP_ECN:
          return !(wc->masks.nw_tos & IP_ECN_MASK);
      case MFF_IP_TTL:
          return !wc->masks.nw_ttl;
  
      case MFF_ND_TARGET:
          return ipv6_mask_is_any(&wc->masks.nd_target);
  
      case MFF_ND_RESERVED:
          return !wc->masks.igmp_group_ip4;
      case MFF_ND_OPTIONS_TYPE:
          return !wc->masks.tcp_flags;
  
      case MFF_IP_FRAG:
          return !(wc->masks.nw_frag & FLOW_NW_FRAG_MASK);
  
      case MFF_ARP_OP:
          return !wc->masks.nw_proto;
      case MFF_ARP_SPA:
          return !wc->masks.nw_src;
      case MFF_ARP_TPA:
          return !wc->masks.nw_dst;
  
      case MFF_TCP_SRC:
      case MFF_UDP_SRC:
      case MFF_SCTP_SRC:
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV6_TYPE:
          return !wc->masks.tp_src;
      case MFF_TCP_DST:
      case MFF_UDP_DST:
      case MFF_SCTP_DST:
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_CODE:
          return !wc->masks.tp_dst;
      case MFF_TCP_FLAGS:
          return !wc->masks.tcp_flags;
  
      case MFF_NSH_FLAGS:
          return !wc->masks.nsh.flags;
      case MFF_NSH_TTL:
          return !wc->masks.nsh.ttl;
      case MFF_NSH_MDTYPE:
          return !wc->masks.nsh.mdtype;
      case MFF_NSH_NP:
          return !wc->masks.nsh.np;
      case MFF_NSH_SPI:
          return !(wc->masks.nsh.path_hdr & htonl(NSH_SPI_MASK));
      case MFF_NSH_SI:
          return !(wc->masks.nsh.path_hdr & htonl(NSH_SI_MASK));
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          return !wc->masks.nsh.context[mf->id - MFF_NSH_C1];
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /* zq:*/
  bool
  pof_mf_is_all_wild(const struct mf_field *mf, const struct pof_flow_wildcards *wc)
  {
      switch (mf->id) {
          case MFF_FIELD_ID0:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
          case MFF_FIELD_ID1:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
          case MFF_FIELD_ID2:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
          case MFF_FIELD_ID3:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
          case MFF_FIELD_ID4:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
          case MFF_FIELD_ID5:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
          case MFF_FIELD_ID6:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
          case MFF_FIELD_ID7:
              return !wc->masks.field_id[mf->id - MFF_FIELD_ID0];
  
          case MFF_OFFSET0:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
          case MFF_OFFSET1:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
          case MFF_OFFSET2:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
          case MFF_OFFSET3:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
          case MFF_OFFSET4:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
          case MFF_OFFSET5:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
          case MFF_OFFSET6:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
          case MFF_OFFSET7:
              return !wc->masks.offset[mf->id - MFF_OFFSET0];
  
          case MFF_LENGTH0:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
          case MFF_LENGTH1:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
          case MFF_LENGTH2:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
          case MFF_LENGTH3:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
          case MFF_LENGTH4:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
          case MFF_LENGTH5:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
          case MFF_LENGTH6:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
          case MFF_LENGTH7:
              return !wc->masks.len[mf->id - MFF_LENGTH0];
  
          case MFF_VALUE0:
          case MFF_VALUE1:
          case MFF_VALUE2:
          case MFF_VALUE3:
          case MFF_VALUE4:
          case MFF_VALUE5:
          case MFF_VALUE6:
          case MFF_VALUE7:
              return 1;
  
          default:
              OVS_NOT_REACHED();
      }
  }
  
  /* Initializes 'mask' with the wildcard bit pattern for field 'mf' within 'wc'.
   * Each bit in 'mask' will be set to 1 if the bit is significant for matching
   * purposes, or to 0 if it is wildcarded.
   *
   * The caller is responsible for ensuring that 'wc' corresponds to a flow that
   * meets 'mf''s prerequisites. */
  void
  mf_get_mask(const struct mf_field *mf, const struct flow_wildcards *wc,
              union mf_value *mask)
  {
      mf_get_value(mf, &wc->masks, mask);
  }
  
  /* Tests whether 'mask' is a valid wildcard bit pattern for 'mf'.  Returns true
   * if the mask is valid, false otherwise. */
  bool
  mf_is_mask_valid(const struct mf_field *mf, const union mf_value *mask)
  {
      switch (mf->maskable) {
      case MFM_NONE:
          return (is_all_zeros(mask, mf->n_bytes) ||
                  is_all_ones(mask, mf->n_bytes));
  
      case MFM_FULLY:
          return true;
      }
  
      OVS_NOT_REACHED();
  }
  
  /* Returns true if 'flow' meets the prerequisites for 'mf', false otherwise.
   * If a non-NULL 'mask' is passed, zero-valued matches can also be verified.
   * Sets inspected bits in 'wc', if non-NULL. */
  static bool
  mf_are_prereqs_ok__(const struct mf_field *mf, const struct flow *flow,
                      const struct flow_wildcards *mask,
                      struct flow_wildcards *wc)
  {
      ovs_be16 dl_type = get_dl_type(flow);
  
      switch (mf->prereqs) {
      case MFP_NONE:
          return true;
      case MFP_ETHERNET:
          return is_ethernet(flow, wc);
      case MFP_ARP:
          return (dl_type == htons(ETH_TYPE_ARP) ||
                  dl_type == htons(ETH_TYPE_RARP));
      case MFP_IPV4:
          return dl_type == htons(ETH_TYPE_IP);
      case MFP_IPV6:
          return dl_type == htons(ETH_TYPE_IPV6);
      case MFP_VLAN_VID:
          return is_vlan(flow, wc);
      case MFP_MPLS:
          return eth_type_mpls(dl_type);
      case MFP_IP_ANY:
          return is_ip_any(flow);
      case MFP_NSH:
          return dl_type == htons(ETH_TYPE_NSH);
      case MFP_CT_VALID:
          return is_ct_valid(flow, mask, wc);
      case MFP_TCP:
          /* Matching !FRAG_LATER is not enforced (mask is not checked). */
          return is_tcp(flow, wc) && !(flow->nw_frag & FLOW_NW_FRAG_LATER);
      case MFP_UDP:
          return is_udp(flow, wc) && !(flow->nw_frag & FLOW_NW_FRAG_LATER);
      case MFP_SCTP:
          return is_sctp(flow, wc) && !(flow->nw_frag & FLOW_NW_FRAG_LATER);
      case MFP_ICMPV4:
          return is_icmpv4(flow, wc);
      case MFP_ICMPV6:
          return is_icmpv6(flow, wc);
      case MFP_ND:
          return is_nd(flow, wc);
      case MFP_ND_SOLICIT:
          return is_nd(flow, wc) && flow->tp_src == htons(ND_NEIGHBOR_SOLICIT);
      case MFP_ND_ADVERT:
          return is_nd(flow, wc) && flow->tp_src == htons(ND_NEIGHBOR_ADVERT);
      }
  
      OVS_NOT_REACHED();
  }
  
  /* Returns true if 'flow' meets the prerequisites for 'mf', false otherwise.
   * Sets inspected bits in 'wc', if non-NULL. */
  bool
  mf_are_prereqs_ok(const struct mf_field *mf, const struct flow *flow,
                    struct flow_wildcards *wc)
  {
      return mf_are_prereqs_ok__(mf, flow, NULL, wc);
  }
  
  /* Returns true if 'match' meets the prerequisites for 'mf', false otherwise.
   */
  bool
  mf_are_match_prereqs_ok(const struct mf_field *mf, const struct match *match)
  {
      return mf_are_prereqs_ok__(mf, &match->flow, &match->wc, NULL);
  }
  
  /* Returns true if 'value' may be a valid value *as part of a masked match*,
   * false otherwise.
   *
   * A value is not rejected just because it is not valid for the field in
   * question, but only if it doesn't make sense to test the bits in question at
   * all.  For example, the MFF_VLAN_TCI field will never have a nonzero value
   * without the VLAN_CFI bit being set, but we can't reject those values because
   * it is still legitimate to test just for those bits (see the documentation
   * for NXM_OF_VLAN_TCI in meta-flow.h).  On the other hand, there is never a
   * reason to set the low bit of MFF_IP_DSCP to 1, so we reject that. */
  bool
  mf_is_value_valid(const struct mf_field *mf, const union mf_value *value)
  {
      switch (mf->id) {
      case MFF_DP_HASH:
      case MFF_RECIRC_ID:
      case MFF_PACKET_TYPE:
      case MFF_CONJ_ID:
      case MFF_TUN_ID:
      case MFF_TUN_SRC:
      case MFF_TUN_DST:
      case MFF_TUN_IPV6_SRC:
      case MFF_TUN_IPV6_DST:
      case MFF_TUN_TOS:
      case MFF_TUN_TTL:
      case MFF_TUN_GBP_ID:
      case MFF_TUN_GBP_FLAGS:
      case MFF_TUN_ERSPAN_IDX:
      case MFF_TUN_ERSPAN_VER:
      case MFF_TUN_ERSPAN_DIR:
      case MFF_TUN_ERSPAN_HWID:
      CASE_MFF_TUN_METADATA:
      case MFF_METADATA:
      case MFF_IN_PORT:
      case MFF_SKB_PRIORITY:
      case MFF_PKT_MARK:
      case MFF_CT_ZONE:
      case MFF_CT_MARK:
      case MFF_CT_LABEL:
      case MFF_CT_NW_PROTO:
      case MFF_CT_NW_SRC:
      case MFF_CT_NW_DST:
      case MFF_CT_IPV6_SRC:
      case MFF_CT_IPV6_DST:
      case MFF_CT_TP_SRC:
      case MFF_CT_TP_DST:
      CASE_MFF_REGS:
      CASE_MFF_XREGS:
      CASE_MFF_XXREGS:
      case MFF_ETH_SRC:
      case MFF_ETH_DST:
      case MFF_ETH_TYPE:
      case MFF_VLAN_TCI:
      case MFF_MPLS_TTL:
      case MFF_IPV4_SRC:
      case MFF_IPV4_DST:
      case MFF_IPV6_SRC:
      case MFF_IPV6_DST:
      case MFF_IP_PROTO:
      case MFF_IP_TTL:
      case MFF_ARP_SPA:
      case MFF_ARP_TPA:
      case MFF_ARP_SHA:
      case MFF_ARP_THA:
      case MFF_TCP_SRC:
      case MFF_TCP_DST:
      case MFF_UDP_SRC:
      case MFF_UDP_DST:
      case MFF_SCTP_SRC:
      case MFF_SCTP_DST:
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_TYPE:
      case MFF_ICMPV6_CODE:
      case MFF_ND_TARGET:
      case MFF_ND_SLL:
      case MFF_ND_TLL:
      case MFF_ND_RESERVED:
      case MFF_ND_OPTIONS_TYPE:
          return true;
  
      case MFF_IN_PORT_OXM:
      case MFF_ACTSET_OUTPUT: {
          ofp_port_t port;
          return !ofputil_port_from_ofp11(value->be32, &port);
      }
  
      case MFF_IP_DSCP:
          return !(value->u8 & ~IP_DSCP_MASK);
      case MFF_IP_DSCP_SHIFTED:
          return !(value->u8 & (~IP_DSCP_MASK >> 2));
      case MFF_IP_ECN:
          return !(value->u8 & ~IP_ECN_MASK);
      case MFF_IP_FRAG:
          return !(value->u8 & ~FLOW_NW_FRAG_MASK);
      case MFF_TCP_FLAGS:
          return !(value->be16 & ~htons(0x0fff));
  
      case MFF_ARP_OP:
          return !(value->be16 & htons(0xff00));
  
      case MFF_DL_VLAN:
          return !(value->be16 & htons(VLAN_CFI | VLAN_PCP_MASK));
      case MFF_VLAN_VID:
          return !(value->be16 & htons(VLAN_PCP_MASK));
  
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
          return !(value->u8 & ~(VLAN_PCP_MASK >> VLAN_PCP_SHIFT));
  
      case MFF_IPV6_LABEL:
          return !(value->be32 & ~htonl(IPV6_LABEL_MASK));
  
      case MFF_MPLS_LABEL:
          return !(value->be32 & ~htonl(MPLS_LABEL_MASK >> MPLS_LABEL_SHIFT));
  
      case MFF_MPLS_TC:
          return !(value->u8 & ~(MPLS_TC_MASK >> MPLS_TC_SHIFT));
  
      case MFF_MPLS_BOS:
          return !(value->u8 & ~(MPLS_BOS_MASK >> MPLS_BOS_SHIFT));
  
      case MFF_TUN_FLAGS:
          return !(value->be16 & ~htons(FLOW_TNL_PUB_F_MASK));
  
      case MFF_CT_STATE:
          return !(value->be32 & ~htonl(CS_SUPPORTED_MASK));
  
      case MFF_NSH_FLAGS:
          return true;
      case MFF_NSH_TTL:
          return (value->u8 <= 63);
      case MFF_NSH_MDTYPE:
          return (value->u8 == 1 || value->u8 == 2);
      case MFF_NSH_NP:
          return true;
      case MFF_NSH_SPI:
          return !(value->be32 & htonl(0xFF000000));
      case MFF_NSH_SI:
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          return true;
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /* zq:Copies the value of field 'mf' from 'flow' into 'value'.  The caller is
   * responsible for ensuring that 'flow' meets 'mf''s prerequisites. */
  void
  pof_mf_get_value(const struct pof_match_u *mf, const struct pof_fp_flow *flow,
                   union mf_value *value)
  {
      int i = (mf->offset/8);
      /*to do: considering the appropriate length of a field in struct pof_fp_flow. */
      value->be64 = flow->pof_normal[i];
      /*VLOG_INFO("++++++tsf pof_mf_get_value: value->be64:%d", ntohll(value->be64));*/
  }
  
  /* Copies the value of field 'mf' from 'flow' into 'value'.  The caller is
   * responsible for ensuring that 'flow' meets 'mf''s prerequisites. */
  void
  mf_get_value(const struct mf_field *mf, const struct flow *flow,
               union mf_value *value)
  {
      switch (mf->id) {
      case MFF_DP_HASH:
          value->be32 = htonl(flow->dp_hash);
          break;
      case MFF_RECIRC_ID:
          value->be32 = htonl(flow->recirc_id);
          break;
      case MFF_PACKET_TYPE:
          value->be32 = flow->packet_type;
          break;
      case MFF_CONJ_ID:
          value->be32 = htonl(flow->conj_id);
          break;
      case MFF_TUN_ID:
          value->be64 = flow->tunnel.tun_id;
          break;
      case MFF_TUN_SRC:
          value->be32 = flow->tunnel.ip_src;
          break;
      case MFF_TUN_DST:
          value->be32 = flow->tunnel.ip_dst;
          break;
      case MFF_TUN_IPV6_SRC:
          value->ipv6 = flow->tunnel.ipv6_src;
          break;
      case MFF_TUN_IPV6_DST:
          value->ipv6 = flow->tunnel.ipv6_dst;
          break;
      case MFF_TUN_FLAGS:
          value->be16 = htons(flow->tunnel.flags & FLOW_TNL_PUB_F_MASK);
          break;
      case MFF_TUN_GBP_ID:
          value->be16 = flow->tunnel.gbp_id;
          break;
      case MFF_TUN_GBP_FLAGS:
          value->u8 = flow->tunnel.gbp_flags;
          break;
      case MFF_TUN_TTL:
          value->u8 = flow->tunnel.ip_ttl;
          break;
      case MFF_TUN_TOS:
          value->u8 = flow->tunnel.ip_tos;
          break;
      case MFF_TUN_ERSPAN_VER:
          value->u8 = flow->tunnel.erspan_ver;
          break;
      case MFF_TUN_ERSPAN_IDX:
          value->be32 = htonl(flow->tunnel.erspan_idx);
          break;
      case MFF_TUN_ERSPAN_DIR:
          value->u8 = flow->tunnel.erspan_dir;
          break;
      case MFF_TUN_ERSPAN_HWID:
          value->u8 = flow->tunnel.erspan_hwid;
          break;
      CASE_MFF_TUN_METADATA:
          tun_metadata_read(&flow->tunnel, mf, value);
          break;
  
      case MFF_METADATA:
          value->be64 = flow->metadata;
          break;
  
      case MFF_IN_PORT:
          value->be16 = htons(ofp_to_u16(flow->in_port.ofp_port));
          break;
      case MFF_IN_PORT_OXM:
          value->be32 = ofputil_port_to_ofp11(flow->in_port.ofp_port);
          break;
      case MFF_ACTSET_OUTPUT:
          value->be32 = ofputil_port_to_ofp11(flow->actset_output);
          break;
  
      case MFF_SKB_PRIORITY:
          value->be32 = htonl(flow->skb_priority);
          break;
  
      case MFF_PKT_MARK:
          value->be32 = htonl(flow->pkt_mark);
          break;
  
      case MFF_CT_STATE:
          value->be32 = htonl(flow->ct_state);
          break;
  
      case MFF_CT_ZONE:
          value->be16 = htons(flow->ct_zone);
          break;
  
      case MFF_CT_MARK:
          value->be32 = htonl(flow->ct_mark);
          break;
  
      case MFF_CT_LABEL:
          value->be128 = hton128(flow->ct_label);
          break;
  
      case MFF_CT_NW_PROTO:
          value->u8 = flow->ct_nw_proto;
          break;
  
      case MFF_CT_NW_SRC:
          value->be32 = flow->ct_nw_src;
          break;
  
      case MFF_CT_NW_DST:
          value->be32 = flow->ct_nw_dst;
          break;
  
      case MFF_CT_IPV6_SRC:
          value->ipv6 = flow->ct_ipv6_src;
          break;
  
      case MFF_CT_IPV6_DST:
          value->ipv6 = flow->ct_ipv6_dst;
          break;
  
      case MFF_CT_TP_SRC:
          value->be16 = flow->ct_tp_src;
          break;
  
      case MFF_CT_TP_DST:
          value->be16 = flow->ct_tp_dst;
          break;
  
      CASE_MFF_REGS:
          value->be32 = htonl(flow->regs[mf->id - MFF_REG0]);
          break;
  
      CASE_MFF_XREGS:
          value->be64 = htonll(flow_get_xreg(flow, mf->id - MFF_XREG0));
          break;
  
      CASE_MFF_XXREGS:
          value->be128 = hton128(flow_get_xxreg(flow, mf->id - MFF_XXREG0));
          break;
  
      case MFF_ETH_SRC:
          value->mac = flow->dl_src;
          break;
  
      case MFF_ETH_DST:
          value->mac = flow->dl_dst;
          break;
  
      case MFF_ETH_TYPE:
          value->be16 = flow->dl_type;
          break;
  
      case MFF_VLAN_TCI:
          value->be16 = flow->vlans[0].tci;
          break;
  
      case MFF_DL_VLAN:
          value->be16 = flow->vlans[0].tci & htons(VLAN_VID_MASK);
          break;
      case MFF_VLAN_VID:
          value->be16 = flow->vlans[0].tci & htons(VLAN_VID_MASK | VLAN_CFI);
          break;
  
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
          value->u8 = vlan_tci_to_pcp(flow->vlans[0].tci);
          break;
  
      case MFF_MPLS_LABEL:
          value->be32 = htonl(mpls_lse_to_label(flow->mpls_lse[0]));
          break;
  
      case MFF_MPLS_TC:
          value->u8 = mpls_lse_to_tc(flow->mpls_lse[0]);
          break;
  
      case MFF_MPLS_BOS:
          value->u8 = mpls_lse_to_bos(flow->mpls_lse[0]);
          break;
  
      case MFF_MPLS_TTL:
          value->u8 = mpls_lse_to_ttl(flow->mpls_lse[0]);
          break;
  
      case MFF_IPV4_SRC:
          value->be32 = flow->nw_src;
          break;
  
      case MFF_IPV4_DST:
          value->be32 = flow->nw_dst;
          break;
  
      case MFF_IPV6_SRC:
          value->ipv6 = flow->ipv6_src;
          break;
  
      case MFF_IPV6_DST:
          value->ipv6 = flow->ipv6_dst;
          break;
  
      case MFF_IPV6_LABEL:
          value->be32 = flow->ipv6_label;
          break;
  
      case MFF_IP_PROTO:
          value->u8 = flow->nw_proto;
          break;
  
      case MFF_IP_DSCP:
          value->u8 = flow->nw_tos & IP_DSCP_MASK;
          break;
  
      case MFF_IP_DSCP_SHIFTED:
          value->u8 = flow->nw_tos >> 2;
          break;
  
      case MFF_IP_ECN:
          value->u8 = flow->nw_tos & IP_ECN_MASK;
          break;
  
      case MFF_IP_TTL:
          value->u8 = flow->nw_ttl;
          break;
  
      case MFF_IP_FRAG:
          value->u8 = flow->nw_frag;
          break;
  
      case MFF_ARP_OP:
          value->be16 = htons(flow->nw_proto);
          break;
  
      case MFF_ARP_SPA:
          value->be32 = flow->nw_src;
          break;
  
      case MFF_ARP_TPA:
          value->be32 = flow->nw_dst;
          break;
  
      case MFF_ARP_SHA:
      case MFF_ND_SLL:
          value->mac = flow->arp_sha;
          break;
  
      case MFF_ARP_THA:
      case MFF_ND_TLL:
          value->mac = flow->arp_tha;
          break;
  
      case MFF_TCP_SRC:
      case MFF_UDP_SRC:
      case MFF_SCTP_SRC:
          value->be16 = flow->tp_src;
          break;
  
      case MFF_TCP_DST:
      case MFF_UDP_DST:
      case MFF_SCTP_DST:
          value->be16 = flow->tp_dst;
          break;
  
      case MFF_TCP_FLAGS:
      case MFF_ND_OPTIONS_TYPE:
          value->be16 = flow->tcp_flags;
          break;
  
      case MFF_ND_RESERVED:
          value->be32 = flow->igmp_group_ip4;
          break;
  
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV6_TYPE:
          value->u8 = ntohs(flow->tp_src);
          break;
  
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_CODE:
          value->u8 = ntohs(flow->tp_dst);
          break;
  
      case MFF_ND_TARGET:
          value->ipv6 = flow->nd_target;
          break;
  
      case MFF_NSH_FLAGS:
          value->u8 = flow->nsh.flags;
          break;
      case MFF_NSH_TTL:
          value->u8 = flow->nsh.ttl;
          break;
      case MFF_NSH_MDTYPE:
          value->u8 = flow->nsh.mdtype;
          break;
      case MFF_NSH_NP:
          value->u8 = flow->nsh.np;
          break;
      case MFF_NSH_SPI:
          value->be32 = nsh_path_hdr_to_spi(flow->nsh.path_hdr);
          if (value->be32 == htonl(NSH_SPI_MASK >> NSH_SPI_SHIFT)) {
              value->be32 = OVS_BE32_MAX;
          }
          break;
      case MFF_NSH_SI:
          value->u8 = nsh_path_hdr_to_si(flow->nsh.path_hdr);
          break;
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          value->be32 = flow->nsh.context[mf->id - MFF_NSH_C1];
          break;
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /* Makes 'match' match field 'mf' exactly, with the value matched taken from
   * 'value'.  The caller is responsible for ensuring that 'match' meets 'mf''s
   * prerequisites.
   *
   * If non-NULL, 'err_str' returns a malloc'ed string describing any errors
   * with the request or NULL if there is no error. The caller is reponsible
   * for freeing the string. */
  void
  mf_set_value(const struct mf_field *mf,
               const union mf_value *value, struct match *match, char **err_str)
  {
      if (err_str) {
          *err_str = NULL;
      }
  
      switch (mf->id) {
      case MFF_DP_HASH:
          match_set_dp_hash(match, ntohl(value->be32));
          break;
      case MFF_RECIRC_ID:
          match_set_recirc_id(match, ntohl(value->be32));
          break;
      case MFF_PACKET_TYPE:
          match_set_packet_type(match, value->be32);
          break;
      case MFF_CONJ_ID:
          match_set_conj_id(match, ntohl(value->be32));
          break;
      case MFF_TUN_ID:
          match_set_tun_id(match, value->be64);
          break;
      case MFF_TUN_SRC:
          match_set_tun_src(match, value->be32);
          break;
      case MFF_TUN_DST:
          match_set_tun_dst(match, value->be32);
          break;
      case MFF_TUN_IPV6_SRC:
          match_set_tun_ipv6_src(match, &value->ipv6);
          break;
      case MFF_TUN_IPV6_DST:
          match_set_tun_ipv6_dst(match, &value->ipv6);
          break;
      case MFF_TUN_FLAGS:
          match_set_tun_flags(match, ntohs(value->be16));
          break;
      case MFF_TUN_GBP_ID:
           match_set_tun_gbp_id(match, value->be16);
           break;
      case MFF_TUN_GBP_FLAGS:
           match_set_tun_gbp_flags(match, value->u8);
           break;
      case MFF_TUN_TOS:
          match_set_tun_tos(match, value->u8);
          break;
      case MFF_TUN_TTL:
          match_set_tun_ttl(match, value->u8);
          break;
      case MFF_TUN_ERSPAN_VER:
          match_set_tun_erspan_ver(match, value->u8);
          break;
      case MFF_TUN_ERSPAN_IDX:
          match_set_tun_erspan_idx(match, ntohl(value->be32));
          break;
      case MFF_TUN_ERSPAN_DIR:
          match_set_tun_erspan_dir(match, value->u8);
          break;
      case MFF_TUN_ERSPAN_HWID:
          match_set_tun_erspan_hwid(match, value->u8);
          break;
      CASE_MFF_TUN_METADATA:
          tun_metadata_set_match(mf, value, NULL, match, err_str);
          break;
  
      case MFF_METADATA:
          match_set_metadata(match, value->be64);
          break;
  
      case MFF_IN_PORT:
          match_set_in_port(match, u16_to_ofp(ntohs(value->be16)));
          break;
  
      case MFF_IN_PORT_OXM: {
          ofp_port_t port;
          ofputil_port_from_ofp11(value->be32, &port);
          match_set_in_port(match, port);
          break;
      }
      case MFF_ACTSET_OUTPUT: {
          ofp_port_t port;
          ofputil_port_from_ofp11(value->be32, &port);
          match_set_actset_output(match, port);
          break;
      }
  
      case MFF_SKB_PRIORITY:
          match_set_skb_priority(match, ntohl(value->be32));
          break;
  
      case MFF_PKT_MARK:
          match_set_pkt_mark(match, ntohl(value->be32));
          break;
  
      case MFF_CT_STATE:
          match_set_ct_state(match, ntohl(value->be32));
          break;
  
      case MFF_CT_ZONE:
          match_set_ct_zone(match, ntohs(value->be16));
          break;
  
      case MFF_CT_MARK:
          match_set_ct_mark(match, ntohl(value->be32));
          break;
  
      case MFF_CT_LABEL:
          match_set_ct_label(match, ntoh128(value->be128));
          break;
  
      case MFF_CT_NW_PROTO:
          match_set_ct_nw_proto(match, value->u8);
          break;
  
      case MFF_CT_NW_SRC:
          match_set_ct_nw_src(match, value->be32);
          break;
  
      case MFF_CT_NW_DST:
          match_set_ct_nw_dst(match, value->be32);
          break;
  
      case MFF_CT_IPV6_SRC:
          match_set_ct_ipv6_src(match, &value->ipv6);
          break;
  
      case MFF_CT_IPV6_DST:
          match_set_ct_ipv6_dst(match, &value->ipv6);
          break;
  
      case MFF_CT_TP_SRC:
          match_set_ct_tp_src(match, value->be16);
          break;
  
      case MFF_CT_TP_DST:
          match_set_ct_tp_dst(match, value->be16);
          break;
  
      CASE_MFF_REGS:
          match_set_reg(match, mf->id - MFF_REG0, ntohl(value->be32));
          break;
  
      CASE_MFF_XREGS:
          match_set_xreg(match, mf->id - MFF_XREG0, ntohll(value->be64));
          break;
  
      CASE_MFF_XXREGS:
          match_set_xxreg(match, mf->id - MFF_XXREG0, ntoh128(value->be128));
          break;
  
      case MFF_ETH_SRC:
          match_set_dl_src(match, value->mac);
          break;
  
      case MFF_ETH_DST:
          match_set_dl_dst(match, value->mac);
          break;
  
      case MFF_ETH_TYPE:
          match_set_dl_type(match, value->be16);
          break;
  
      case MFF_VLAN_TCI:
          match_set_dl_tci(match, value->be16);
          break;
  
      case MFF_DL_VLAN:
          match_set_dl_vlan(match, value->be16, 0);
          break;
      case MFF_VLAN_VID:
          match_set_vlan_vid(match, value->be16);
          break;
  
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
          match_set_dl_vlan_pcp(match, value->u8, 0);
          break;
  
      case MFF_MPLS_LABEL:
          match_set_mpls_label(match, 0, value->be32);
          break;
  
      case MFF_MPLS_TC:
          match_set_mpls_tc(match, 0, value->u8);
          break;
  
      case MFF_MPLS_BOS:
          match_set_mpls_bos(match, 0, value->u8);
          break;
  
      case MFF_MPLS_TTL:
          match_set_mpls_ttl(match, 0, value->u8);
          break;
  
      case MFF_IPV4_SRC:
          match_set_nw_src(match, value->be32);
          break;
  
      case MFF_IPV4_DST:
          match_set_nw_dst(match, value->be32);
          break;
  
      case MFF_IPV6_SRC:
          match_set_ipv6_src(match, &value->ipv6);
          break;
  
      case MFF_IPV6_DST:
          match_set_ipv6_dst(match, &value->ipv6);
          break;
  
      case MFF_IPV6_LABEL:
          match_set_ipv6_label(match, value->be32);
          break;
  
      case MFF_IP_PROTO:
          match_set_nw_proto(match, value->u8);
          break;
  
      case MFF_IP_DSCP:
          match_set_nw_dscp(match, value->u8);
          break;
  
      case MFF_IP_DSCP_SHIFTED:
          match_set_nw_dscp(match, value->u8 << 2);
          break;
  
      case MFF_IP_ECN:
          match_set_nw_ecn(match, value->u8);
          break;
  
      case MFF_IP_TTL:
          match_set_nw_ttl(match, value->u8);
          break;
  
      case MFF_IP_FRAG:
          match_set_nw_frag(match, value->u8);
          break;
  
      case MFF_ARP_OP:
          match_set_nw_proto(match, ntohs(value->be16));
          break;
  
      case MFF_ARP_SPA:
          match_set_nw_src(match, value->be32);
          break;
  
      case MFF_ARP_TPA:
          match_set_nw_dst(match, value->be32);
          break;
  
      case MFF_ARP_SHA:
      case MFF_ND_SLL:
          match_set_arp_sha(match, value->mac);
          break;
  
      case MFF_ARP_THA:
      case MFF_ND_TLL:
          match_set_arp_tha(match, value->mac);
          break;
  
      case MFF_TCP_SRC:
      case MFF_UDP_SRC:
      case MFF_SCTP_SRC:
          match_set_tp_src(match, value->be16);
          break;
  
      case MFF_TCP_DST:
      case MFF_UDP_DST:
      case MFF_SCTP_DST:
          match_set_tp_dst(match, value->be16);
          break;
  
      case MFF_TCP_FLAGS:
          match_set_tcp_flags(match, value->be16);
          break;
  
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV6_TYPE:
          match_set_icmp_type(match, value->u8);
          break;
  
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_CODE:
          match_set_icmp_code(match, value->u8);
          break;
  
      case MFF_ND_TARGET:
          match_set_nd_target(match, &value->ipv6);
          break;
  
      case MFF_ND_RESERVED:
          match_set_nd_reserved(match, value->be32);
          break;
  
      case MFF_ND_OPTIONS_TYPE:
          match_set_nd_options_type(match, value->u8);
          break;
  
      case MFF_NSH_FLAGS:
          MATCH_SET_FIELD_UINT8(match, nsh.flags, value->u8);
          break;
      case MFF_NSH_TTL:
          MATCH_SET_FIELD_UINT8(match, nsh.ttl, value->u8);
          break;
      case MFF_NSH_MDTYPE:
          MATCH_SET_FIELD_UINT8(match, nsh.mdtype, value->u8);
          break;
      case MFF_NSH_NP:
          MATCH_SET_FIELD_UINT8(match, nsh.np, value->u8);
          break;
      case MFF_NSH_SPI:
          match->wc.masks.nsh.path_hdr |= htonl(NSH_SPI_MASK);
          nsh_path_hdr_set_spi(&match->flow.nsh.path_hdr, value->be32);
          break;
      case MFF_NSH_SI:
          match->wc.masks.nsh.path_hdr |= htonl(NSH_SI_MASK);
          nsh_path_hdr_set_si(&match->flow.nsh.path_hdr, value->u8);
          break;
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          MATCH_SET_FIELD_BE32(match, nsh.context[mf->id - MFF_NSH_C1],
                               value->be32);
          break;
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /*zq*/
  void
  pof_mf_set_value(const struct mf_field *mf,
                   const union mf_value *value, struct match_x *match, char **err_str)
  {
      if (err_str) {
          *err_str = NULL;
      }
  
      switch (mf->id) {
          case MFF_FIELD_ID0:
          case MFF_FIELD_ID1:
          case MFF_FIELD_ID2:
          case MFF_FIELD_ID3:
          case MFF_FIELD_ID4:
          case MFF_FIELD_ID5:
          case MFF_FIELD_ID6:
          case MFF_FIELD_ID7:
              /*VLOG_INFO("+++++++++++sqy pof_mf_set_value: MFF_FIELD_ID %u", ntohs(match->flow.field_id));*/
              pof_match_set_field_id(match, mf->id - MFF_FIELD_ID0, value->be16);
              break;
  
          case MFF_OFFSET0:
          case MFF_OFFSET1:
          case MFF_OFFSET2:
          case MFF_OFFSET3:
          case MFF_OFFSET4:
          case MFF_OFFSET5:
          case MFF_OFFSET6:
          case MFF_OFFSET7:
              VLOG_INFO("+++++++++++sqy pof_mf_set_value: MFF_OFFSET %u", ntohs(match->flow.offset));
              pof_match_set_offset(match, mf->id - MFF_OFFSET0, value->be16);
              break;
  
          case MFF_LENGTH0:
          case MFF_LENGTH1:
          case MFF_LENGTH2:
          case MFF_LENGTH3:
          case MFF_LENGTH4:
          case MFF_LENGTH5:
          case MFF_LENGTH6:
          case MFF_LENGTH7:
              /*VLOG_INFO("+++++++++++sqy pof_mf_set_value: MFF_LENGTH %u", ntohs(match->flow.len));*/
              pof_match_set_length(match, mf->id - MFF_LENGTH0, value->be16);
              break;
  
          case MFF_VALUE0:
          case MFF_VALUE1:
          case MFF_VALUE2:
          case MFF_VALUE3:
          case MFF_VALUE4:
          case MFF_VALUE5:
          case MFF_VALUE6:
          case MFF_VALUE7:
              VLOG_INFO("+++++++++++sqy pof_mf_set_value: MFF_VALUE7");
              /*if (match->flow.len>0 && match->flow.len<=8){
                  pof_match_set_value8(match, mf->id - MFF_VALUE0, value->u8);
              }else if (match->flow.len>8 && match->flow.len<=16){
                  pof_match_set_value16(match, mf->id - MFF_VALUE0, value->be16);
              }else if (match->flow.len>16 && match->flow.len<=32){
                  pof_match_set_value32(match, mf->id - MFF_VALUE0, value->be32);
              }else if (match->flow.len>32 && match->flow.len<=48){
                  pof_match_set_value48(match, mf->id - MFF_VALUE0, value->mac);
              }else if (match->flow.len>48 && match->flow.len<=64){
                  pof_match_set_value64(match, mf->id - MFF_VALUE0, value->be64);
              }else if (match->flow.len>64){
                  pof_match_set_value(match, mf->id - MFF_VALUE0, &value->ipv6);
              }*/
              pof_match_set_value(match, mf->id - MFF_VALUE0, &value->ipv6);
              break;
  
          default:
              OVS_NOT_REACHED();
      }
  }
  
  /* Unwildcard the bits in 'mask' of the 'wc' member field described by 'mf'.
   * The caller is responsible for ensuring that 'wc' meets 'mf''s
   * prerequisites. */
  void
  mf_mask_field_masked(const struct mf_field *mf, const union mf_value *mask,
                       struct flow_wildcards *wc)
  {
      union mf_value temp_mask;
      /* For MFF_DL_VLAN, we cannot send a all 1's to flow_set_dl_vlan() as that
       * will be considered as OFP10_VLAN_NONE. So make sure the mask only has
       * valid bits in this case. */
      if (mf->id == MFF_DL_VLAN) {
          temp_mask.be16 = htons(VLAN_VID_MASK) & mask->be16;
          mask = &temp_mask;
      }
  
      union mf_value mask_value;
  
      mf_get_value(mf, &wc->masks, &mask_value);
      for (size_t i = 0; i < mf->n_bytes; i++) {
          mask_value.b[i] |= mask->b[i];
      }
      mf_set_flow_value(mf, &mask_value, &wc->masks);
  }
  
  void
  pof_mf_mask_field_masked(const struct pof_match_u *mf, const union mf_value *mask,
                           struct pof_fp_flow_wildcards *wc)
  {
      union mf_value mask_value;
      int inner_off = mf->offset - (mf->offset/8)*8;
      int i = inner_off;
  
      pof_mf_get_value(mf, &wc->masks, &mask_value);
      /*VLOG_INFO("+++++++++++sqy pof_mf_mask_field_masked: inneroff=%d, mf->len=%d", inner_off , mf->len );*/
      int len = inner_off + mf->len;
      for ( ; i < len && i < 8; i++) {
          /*VLOG_INFO("+++++++++++sqy pof_mf_mask_field_masked 111: mask_value.b[%d] =%d,mask->b[%d] =%d",
                            i, mask_value.b[i], i-inner_off, mask->b[i-inner_off]);*/
          mask_value.b[i] |= mask->b[i-inner_off];
          /*VLOG_INFO("+++++++++++sqy pof_mf_mask_field_masked 222: mask_value.b[%d] =%d,mask->b[%d] =%d",
                   i, mask_value.b[i], i-inner_off, mask->b[i-inner_off]);*/
      }
  
      /* to do: the field which will be 'set_field' corrosponds to more than
       * one field in struct pof_fp_flow.
       * while( len - 8 >0){
          len = len -8;
          for (size_t z = 0 ; z < len && z < 8 && i<128; z++, i++) {
              mask_value.b[i] |= mask->b[i-j];
          }
      }*/
      pof_mf_set_flow_value(mf, &mask_value, &wc->masks);
  }
  
  /* Unwildcard 'wc' member field described by 'mf'.  The caller is
   * responsible for ensuring that 'mask' meets 'mf''s prerequisites. */
  void
  mf_mask_field(const struct mf_field *mf, struct flow_wildcards *wc)
  {
      mf_mask_field_masked(mf, &exact_match_mask, wc);
  }
  
  static int
  field_len(const struct mf_field *mf, const union mf_value *value_)
  {
      const uint8_t *value = &value_->u8;
      int i;
  
      if (!mf->variable_len) {
          return mf->n_bytes;
      }
  
      if (!value) {
          return 0;
      }
  
      for (i = 0; i < mf->n_bytes; i++) {
          if (value[i] != 0) {
              break;
          }
      }
  
      return mf->n_bytes - i;
  }
  
  /* Returns the effective length of the field. For fixed length fields,
   * this is just the defined length. For variable length fields, it is
   * the minimum size encoding that retains the same meaning (i.e.
   * discarding leading zeros).
   *
   * 'is_masked' returns (if non-NULL) whether the original contained
   * a mask. Otherwise, a mask that is the same length as the value
   * might be misinterpreted as an exact match. */
  int
  mf_field_len(const struct mf_field *mf, const union mf_value *value,
               const union mf_value *mask, bool *is_masked_)
  {
      int len, mask_len;
      bool is_masked = mask && !is_all_ones(mask, mf->n_bytes);
  
      len = field_len(mf, value);
      if (is_masked) {
          mask_len = field_len(mf, mask);
          len = MAX(len, mask_len);
      }
  
      if (is_masked_) {
          *is_masked_ = is_masked;
      }
  
      return len;
  }
  
  /* Sets 'flow' member field described by 'mf' to 'value'.  The caller is
   * responsible for ensuring that 'flow' meets 'mf''s prerequisites.*/
  void
  pof_mf_set_flow_value(const struct pof_match_u *mf,
                      const union mf_value *value, struct pof_fp_flow *flow)
  {
      int i = (mf->offset/8);
      /*VLOG_INFO("+++++++++++sqy pof_mf_set_flow_value 111");*/
      /*to do: considering the appropriate length of a field in struct pof_fp_flow. */
      flow->pof_normal[i] = value->be64;
      /*VLOG_INFO("+++++++++++sqy pof_mf_set_flow_value 222, flow->normal[%d]=%d",i, ntohll(flow->pof_normal[i]));*/
  }
  
  /* Sets 'flow' member field described by 'mf' to 'value'.  The caller is
   * responsible for ensuring that 'flow' meets 'mf''s prerequisites.*/
  void
  mf_set_flow_value(const struct mf_field *mf,
                    const union mf_value *value, struct flow *flow)
  {
      switch (mf->id) {
      case MFF_DP_HASH:
          flow->dp_hash = ntohl(value->be32);
          break;
      case MFF_RECIRC_ID:
          flow->recirc_id = ntohl(value->be32);
          break;
      case MFF_PACKET_TYPE:
          flow->packet_type = value->be32;
          break;
      case MFF_CONJ_ID:
          flow->conj_id = ntohl(value->be32);
          break;
      case MFF_TUN_ID:
          flow->tunnel.tun_id = value->be64;
          break;
      case MFF_TUN_SRC:
          flow->tunnel.ip_src = value->be32;
          break;
      case MFF_TUN_DST:
          flow->tunnel.ip_dst = value->be32;
          break;
      case MFF_TUN_IPV6_SRC:
          flow->tunnel.ipv6_src = value->ipv6;
          break;
      case MFF_TUN_IPV6_DST:
          flow->tunnel.ipv6_dst = value->ipv6;
          break;
      case MFF_TUN_FLAGS:
          flow->tunnel.flags = (flow->tunnel.flags & ~FLOW_TNL_PUB_F_MASK) |
                               ntohs(value->be16);
          break;
      case MFF_TUN_GBP_ID:
          flow->tunnel.gbp_id = value->be16;
          break;
      case MFF_TUN_GBP_FLAGS:
          flow->tunnel.gbp_flags = value->u8;
          break;
      case MFF_TUN_TOS:
          flow->tunnel.ip_tos = value->u8;
          break;
      case MFF_TUN_TTL:
          flow->tunnel.ip_ttl = value->u8;
          break;
      case MFF_TUN_ERSPAN_VER:
          flow->tunnel.erspan_ver = value->u8;
          break;
      case MFF_TUN_ERSPAN_IDX:
          flow->tunnel.erspan_idx = ntohl(value->be32);
          break;
      case MFF_TUN_ERSPAN_DIR:
          flow->tunnel.erspan_dir = value->u8;
          break;
      case MFF_TUN_ERSPAN_HWID:
          flow->tunnel.erspan_hwid = value->u8;
          break;
      CASE_MFF_TUN_METADATA:
          tun_metadata_write(&flow->tunnel, mf, value);
          break;
      case MFF_METADATA:
          flow->metadata = value->be64;
          break;
  
      case MFF_IN_PORT:
          flow->in_port.ofp_port = u16_to_ofp(ntohs(value->be16));
          break;
      case MFF_IN_PORT_OXM:
          ofputil_port_from_ofp11(value->be32, &flow->in_port.ofp_port);
          break;
      case MFF_ACTSET_OUTPUT:
          ofputil_port_from_ofp11(value->be32, &flow->actset_output);
          break;
  
      case MFF_SKB_PRIORITY:
          flow->skb_priority = ntohl(value->be32);
          break;
  
      case MFF_PKT_MARK:
          flow->pkt_mark = ntohl(value->be32);
          break;
  
      case MFF_CT_STATE:
          flow->ct_state = ntohl(value->be32);
          break;
  
      case MFF_CT_ZONE:
          flow->ct_zone = ntohs(value->be16);
          break;
  
      case MFF_CT_MARK:
          flow->ct_mark = ntohl(value->be32);
          break;
  
      case MFF_CT_LABEL:
          flow->ct_label = ntoh128(value->be128);
          break;
  
      case MFF_CT_NW_PROTO:
          flow->ct_nw_proto = value->u8;
          break;
  
      case MFF_CT_NW_SRC:
          flow->ct_nw_src = value->be32;
          break;
  
      case MFF_CT_NW_DST:
          flow->ct_nw_dst = value->be32;
          break;
  
      case MFF_CT_IPV6_SRC:
          flow->ct_ipv6_src = value->ipv6;
          break;
  
      case MFF_CT_IPV6_DST:
          flow->ct_ipv6_dst = value->ipv6;
          break;
  
      case MFF_CT_TP_SRC:
          flow->ct_tp_src = value->be16;
          break;
  
      case MFF_CT_TP_DST:
          flow->ct_tp_dst = value->be16;
          break;
  
      CASE_MFF_REGS:
          flow->regs[mf->id - MFF_REG0] = ntohl(value->be32);
          break;
  
      CASE_MFF_XREGS:
          flow_set_xreg(flow, mf->id - MFF_XREG0, ntohll(value->be64));
          break;
  
      CASE_MFF_XXREGS:
          flow_set_xxreg(flow, mf->id - MFF_XXREG0, ntoh128(value->be128));
          break;
  
      case MFF_ETH_SRC:
          flow->dl_src = value->mac;
          break;
  
      case MFF_ETH_DST:
          flow->dl_dst = value->mac;
          break;
  
      case MFF_ETH_TYPE:
          flow->dl_type = value->be16;
          break;
  
      case MFF_VLAN_TCI:
          flow->vlans[0].tci = value->be16;
          flow_fix_vlan_tpid(flow);
          break;
  
      case MFF_DL_VLAN:
          flow_set_dl_vlan(flow, value->be16, 0);
          flow_fix_vlan_tpid(flow);
          break;
  
      case MFF_VLAN_VID:
          flow_set_vlan_vid(flow, value->be16);
          flow_fix_vlan_tpid(flow);
          break;
  
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
          flow_set_vlan_pcp(flow, value->u8, 0);
          flow_fix_vlan_tpid(flow);
          break;
  
      case MFF_MPLS_LABEL:
          flow_set_mpls_label(flow, 0, value->be32);
          break;
  
      case MFF_MPLS_TC:
          flow_set_mpls_tc(flow, 0, value->u8);
          break;
  
      case MFF_MPLS_BOS:
          flow_set_mpls_bos(flow, 0, value->u8);
          break;
  
      case MFF_MPLS_TTL:
          flow_set_mpls_ttl(flow, 0, value->u8);
          break;
  
      case MFF_IPV4_SRC:
          flow->nw_src = value->be32;
          break;
  
      case MFF_IPV4_DST:
          flow->nw_dst = value->be32;
          break;
  
      case MFF_IPV6_SRC:
          flow->ipv6_src = value->ipv6;
          break;
  
      case MFF_IPV6_DST:
          flow->ipv6_dst = value->ipv6;
          break;
  
      case MFF_IPV6_LABEL:
          flow->ipv6_label = value->be32 & htonl(IPV6_LABEL_MASK);
          break;
  
      case MFF_IP_PROTO:
          flow->nw_proto = value->u8;
          break;
  
      case MFF_IP_DSCP:
          flow->nw_tos &= ~IP_DSCP_MASK;
          flow->nw_tos |= value->u8 & IP_DSCP_MASK;
          break;
  
      case MFF_IP_DSCP_SHIFTED:
          flow->nw_tos &= ~IP_DSCP_MASK;
          flow->nw_tos |= value->u8 << 2;
          break;
  
      case MFF_IP_ECN:
          flow->nw_tos &= ~IP_ECN_MASK;
          flow->nw_tos |= value->u8 & IP_ECN_MASK;
          break;
  
      case MFF_IP_TTL:
          flow->nw_ttl = value->u8;
          break;
  
      case MFF_IP_FRAG:
          flow->nw_frag = value->u8 & FLOW_NW_FRAG_MASK;
          break;
  
      case MFF_ARP_OP:
          flow->nw_proto = ntohs(value->be16);
          break;
  
      case MFF_ARP_SPA:
          flow->nw_src = value->be32;
          break;
  
      case MFF_ARP_TPA:
          flow->nw_dst = value->be32;
          break;
  
      case MFF_ARP_SHA:
      case MFF_ND_SLL:
          flow->arp_sha = value->mac;
          break;
  
      case MFF_ARP_THA:
      case MFF_ND_TLL:
          flow->arp_tha = value->mac;
          break;
  
      case MFF_TCP_SRC:
      case MFF_UDP_SRC:
      case MFF_SCTP_SRC:
          flow->tp_src = value->be16;
          break;
  
      case MFF_TCP_DST:
      case MFF_UDP_DST:
      case MFF_SCTP_DST:
          flow->tp_dst = value->be16;
          break;
  
      case MFF_TCP_FLAGS:
          flow->tcp_flags = value->be16;
          break;
  
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV6_TYPE:
          flow->tp_src = htons(value->u8);
          break;
  
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_CODE:
          flow->tp_dst = htons(value->u8);
          break;
  
      case MFF_ND_TARGET:
          flow->nd_target = value->ipv6;
          break;
  
      case MFF_ND_RESERVED:
          flow->igmp_group_ip4 = value->be32;
          break;
  
      case MFF_ND_OPTIONS_TYPE:
          flow->tcp_flags = htons(value->u8);
          break;
  
      case MFF_NSH_FLAGS:
          flow->nsh.flags = value->u8;
          break;
      case MFF_NSH_TTL:
          flow->nsh.ttl = value->u8;
          break;
      case MFF_NSH_MDTYPE:
          flow->nsh.mdtype = value->u8;
          break;
      case MFF_NSH_NP:
          flow->nsh.np = value->u8;
          break;
      case MFF_NSH_SPI:
          nsh_path_hdr_set_spi(&flow->nsh.path_hdr, value->be32);
          break;
      case MFF_NSH_SI:
          nsh_path_hdr_set_si(&flow->nsh.path_hdr, value->u8);
          break;
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          flow->nsh.context[mf->id - MFF_NSH_C1] = value->be32;
          break;
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /* Consider each of 'src', 'mask', and 'dst' as if they were arrays of 8*n
   * bits.  Then, for each 0 <= i < 8 * n such that mask[i] == 1, sets dst[i] =
   * src[i].  */
  static void
  apply_mask(const uint8_t *src, const uint8_t *mask, uint8_t *dst, size_t n)
  {
      size_t i;
  
      for (i = 0; i < n; i++) {
          dst[i] = (src[i] & mask[i]) | (dst[i] & ~mask[i]);
      }
  }
  
  /* Sets 'flow' member field described by 'field' to 'value', except that bits
   * for which 'mask' has a 0-bit keep their existing values.  The caller is
   * responsible for ensuring that 'flow' meets 'field''s prerequisites.*/
  void
  mf_set_flow_value_masked(const struct mf_field *field,
                           const union mf_value *value,
                           const union mf_value *mask,
                           struct flow *flow)
  {
      union mf_value tmp;
  
      mf_get_value(field, flow, &tmp);
      apply_mask((const uint8_t *) value, (const uint8_t *) mask,
                 (uint8_t *) &tmp, field->n_bytes);
      mf_set_flow_value(field, &tmp, flow);
  }
  
  void
  pof_mf_set_flow_value_v1(const struct pof_match_u *field,
                           const union mf_value *value,
                           const union mf_value *mask,
                           struct pof_flow *flow, int index)
  {
      union mf_value tmp;
  
      for(int i=0; i<POF_MAX_FIELD_LENGTH_IN_BYTE; i++){
  //        VLOG_INFO("+++++++++++tsf pof_mf_set_flow_value_masked value->b[i]= %d, flow->value[0][i]=%d", value->b[i], flow->value[0][i]);
          flow->value[index][i] = value->b[i];
          flow->mask[index][i] = mask->b[i];
  //        VLOG_INFO("+++++++++++sqy pof_mf_set_flow_value_masked value->b[i]= %d, flow->value[0][i]=%d", value->b[i], flow->value[0][i]);
  //        VLOG_INFO("+++++++++++sqy pof_mf_set_flow_value_masked mask->b[i]= %d, flow->mask[0][i]=%d", mask->b[i], flow->mask[0][i]);
      }
  }
  
  bool
  mf_is_tun_metadata(const struct mf_field *mf)
  {
      return mf->id >= MFF_TUN_METADATA0 &&
             mf->id < MFF_TUN_METADATA0 + TUN_METADATA_NUM_OPTS;
  }
  
  bool
  mf_is_pipeline_field(const struct mf_field *mf)
  {
      switch (mf->id) {
      case MFF_TUN_ID:
      case MFF_TUN_SRC:
      case MFF_TUN_DST:
      case MFF_TUN_IPV6_SRC:
      case MFF_TUN_IPV6_DST:
      case MFF_TUN_FLAGS:
      case MFF_TUN_GBP_ID:
      case MFF_TUN_GBP_FLAGS:
      case MFF_TUN_ERSPAN_VER:
      case MFF_TUN_ERSPAN_IDX:
      case MFF_TUN_ERSPAN_DIR:
      case MFF_TUN_ERSPAN_HWID:
      CASE_MFF_TUN_METADATA:
      case MFF_METADATA:
      case MFF_IN_PORT:
      case MFF_IN_PORT_OXM:
      CASE_MFF_REGS:
      CASE_MFF_XREGS:
      CASE_MFF_XXREGS:
      case MFF_PACKET_TYPE:
          return true;
  
      case MFF_DP_HASH:
      case MFF_RECIRC_ID:
      case MFF_CONJ_ID:
      case MFF_TUN_TTL:
      case MFF_TUN_TOS:
      case MFF_ACTSET_OUTPUT:
      case MFF_SKB_PRIORITY:
      case MFF_PKT_MARK:
      case MFF_CT_STATE:
      case MFF_CT_ZONE:
      case MFF_CT_MARK:
      case MFF_CT_LABEL:
      case MFF_CT_NW_PROTO:
      case MFF_CT_NW_SRC:
      case MFF_CT_NW_DST:
      case MFF_CT_IPV6_SRC:
      case MFF_CT_IPV6_DST:
      case MFF_CT_TP_SRC:
      case MFF_CT_TP_DST:
      case MFF_ETH_SRC:
      case MFF_ETH_DST:
      case MFF_ETH_TYPE:
      case MFF_VLAN_TCI:
      case MFF_DL_VLAN:
      case MFF_VLAN_VID:
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
      case MFF_MPLS_LABEL:
      case MFF_MPLS_TC:
      case MFF_MPLS_BOS:
      case MFF_MPLS_TTL:
      case MFF_IPV4_SRC:
      case MFF_IPV4_DST:
      case MFF_IPV6_SRC:
      case MFF_IPV6_DST:
      case MFF_IPV6_LABEL:
      case MFF_IP_PROTO:
      case MFF_IP_DSCP:
      case MFF_IP_DSCP_SHIFTED:
      case MFF_IP_ECN:
      case MFF_IP_TTL:
      case MFF_IP_FRAG:
      case MFF_ARP_OP:
      case MFF_ARP_SPA:
      case MFF_ARP_TPA:
      case MFF_ARP_SHA:
      case MFF_ARP_THA:
      case MFF_TCP_SRC:
      case MFF_TCP_DST:
      case MFF_TCP_FLAGS:
      case MFF_UDP_SRC:
      case MFF_UDP_DST:
      case MFF_SCTP_SRC:
      case MFF_SCTP_DST:
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_TYPE:
      case MFF_ICMPV6_CODE:
      case MFF_ND_TARGET:
      case MFF_ND_SLL:
      case MFF_ND_TLL:
      case MFF_ND_RESERVED:
      case MFF_ND_OPTIONS_TYPE:
      case MFF_NSH_FLAGS:
      case MFF_NSH_TTL:
      case MFF_NSH_MDTYPE:
      case MFF_NSH_NP:
      case MFF_NSH_SPI:
      case MFF_NSH_SI:
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          return false;
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /* Returns true if 'mf' has previously been set in 'flow', false if
   * it contains a non-default value.
   *
   * The caller is responsible for ensuring that 'flow' meets 'mf''s
   * prerequisites. */
  bool
  mf_is_set(const struct mf_field *mf, const struct flow *flow)
  {
      if (!mf_is_tun_metadata(mf)) {
          union mf_value value;
  
          mf_get_value(mf, flow, &value);
          return !is_all_zeros(&value, mf->n_bytes);
      } else {
          return ULLONG_GET(flow->tunnel.metadata.present.map,
                            mf->id - MFF_TUN_METADATA0);
      }
  }
  
  /* Makes 'match' wildcard field 'mf'.
   *
   * The caller is responsible for ensuring that 'match' meets 'mf''s
   * prerequisites.
   *
   * If non-NULL, 'err_str' returns a malloc'ed string describing any errors
   * with the request or NULL if there is no error. The caller is reponsible
   * for freeing the string. */
  void
  mf_set_wild(const struct mf_field *mf, struct match *match, char **err_str)
  {
      if (err_str) {
          *err_str = NULL;
      }
  
      switch (mf->id) {
      case MFF_DP_HASH:
          match->flow.dp_hash = 0;
          match->wc.masks.dp_hash = 0;
          break;
      case MFF_RECIRC_ID:
          match->flow.recirc_id = 0;
          match->wc.masks.recirc_id = 0;
          break;
      case MFF_PACKET_TYPE:
          match->flow.packet_type = 0;
          match->wc.masks.packet_type = 0;
          break;
      case MFF_CONJ_ID:
          match->flow.conj_id = 0;
          match->wc.masks.conj_id = 0;
          break;
      case MFF_TUN_ID:
          match_set_tun_id_masked(match, htonll(0), htonll(0));
          break;
      case MFF_TUN_SRC:
          match_set_tun_src_masked(match, htonl(0), htonl(0));
          break;
      case MFF_TUN_DST:
          match_set_tun_dst_masked(match, htonl(0), htonl(0));
          break;
      case MFF_TUN_IPV6_SRC:
          memset(&match->wc.masks.tunnel.ipv6_src, 0,
                 sizeof match->wc.masks.tunnel.ipv6_src);
          memset(&match->flow.tunnel.ipv6_src, 0,
                 sizeof match->flow.tunnel.ipv6_src);
          break;
      case MFF_TUN_IPV6_DST:
          memset(&match->wc.masks.tunnel.ipv6_dst, 0,
                 sizeof match->wc.masks.tunnel.ipv6_dst);
          memset(&match->flow.tunnel.ipv6_dst, 0,
                 sizeof match->flow.tunnel.ipv6_dst);
          break;
      case MFF_TUN_FLAGS:
          match_set_tun_flags_masked(match, 0, 0);
          break;
      case MFF_TUN_GBP_ID:
          match_set_tun_gbp_id_masked(match, 0, 0);
          break;
      case MFF_TUN_GBP_FLAGS:
          match_set_tun_gbp_flags_masked(match, 0, 0);
          break;
      case MFF_TUN_TOS:
          match_set_tun_tos_masked(match, 0, 0);
          break;
      case MFF_TUN_TTL:
          match_set_tun_ttl_masked(match, 0, 0);
          break;
      case MFF_TUN_ERSPAN_VER:
          match_set_tun_erspan_ver_masked(match, 0, 0);
          break;
      case MFF_TUN_ERSPAN_IDX:
          match_set_tun_erspan_idx_masked(match, 0, 0);
          break;
      case MFF_TUN_ERSPAN_DIR:
          match_set_tun_erspan_dir_masked(match, 0, 0);
          break;
      case MFF_TUN_ERSPAN_HWID:
          match_set_tun_erspan_hwid_masked(match, 0, 0);
          break;
      CASE_MFF_TUN_METADATA:
          tun_metadata_set_match(mf, NULL, NULL, match, err_str);
          break;
  
      case MFF_METADATA:
          match_set_metadata_masked(match, htonll(0), htonll(0));
          break;
  
      case MFF_IN_PORT:
      case MFF_IN_PORT_OXM:
          match->flow.in_port.ofp_port = 0;
          match->wc.masks.in_port.ofp_port = 0;
          break;
      case MFF_ACTSET_OUTPUT:
          match->flow.actset_output = 0;
          match->wc.masks.actset_output = 0;
          break;
  
      case MFF_SKB_PRIORITY:
          match->flow.skb_priority = 0;
          match->wc.masks.skb_priority = 0;
          break;
  
      case MFF_PKT_MARK:
          match->flow.pkt_mark = 0;
          match->wc.masks.pkt_mark = 0;
          break;
  
      case MFF_CT_STATE:
          match->flow.ct_state = 0;
          match->wc.masks.ct_state = 0;
          break;
  
      case MFF_CT_ZONE:
          match->flow.ct_zone = 0;
          match->wc.masks.ct_zone = 0;
          break;
  
      case MFF_CT_MARK:
          match->flow.ct_mark = 0;
          match->wc.masks.ct_mark = 0;
          break;
  
      case MFF_CT_LABEL:
          memset(&match->flow.ct_label, 0, sizeof(match->flow.ct_label));
          memset(&match->wc.masks.ct_label, 0, sizeof(match->wc.masks.ct_label));
          break;
  
      case MFF_CT_NW_PROTO:
          match->flow.ct_nw_proto = 0;
          match->wc.masks.ct_nw_proto = 0;
          break;
  
      case MFF_CT_NW_SRC:
          match->flow.ct_nw_src = 0;
          match->wc.masks.ct_nw_src = 0;
          break;
  
      case MFF_CT_NW_DST:
          match->flow.ct_nw_dst = 0;
          match->wc.masks.ct_nw_dst = 0;
          break;
  
      case MFF_CT_IPV6_SRC:
          memset(&match->flow.ct_ipv6_src, 0, sizeof(match->flow.ct_ipv6_src));
          WC_UNMASK_FIELD(&match->wc, ct_ipv6_src);
          break;
  
      case MFF_CT_IPV6_DST:
          memset(&match->flow.ct_ipv6_dst, 0, sizeof(match->flow.ct_ipv6_dst));
          WC_UNMASK_FIELD(&match->wc, ct_ipv6_dst);
          break;
  
      case MFF_CT_TP_SRC:
          match->flow.ct_tp_src = 0;
          match->wc.masks.ct_tp_src = 0;
          break;
  
      case MFF_CT_TP_DST:
          match->flow.ct_tp_dst = 0;
          match->wc.masks.ct_tp_dst = 0;
          break;
  
      CASE_MFF_REGS:
          match_set_reg_masked(match, mf->id - MFF_REG0, 0, 0);
          break;
  
      CASE_MFF_XREGS:
          match_set_xreg_masked(match, mf->id - MFF_XREG0, 0, 0);
          break;
  
      CASE_MFF_XXREGS: {
          match_set_xxreg_masked(match, mf->id - MFF_XXREG0, OVS_U128_ZERO,
                                 OVS_U128_ZERO);
          break;
      }
  
      case MFF_ETH_SRC:
          match->flow.dl_src = eth_addr_zero;
          match->wc.masks.dl_src = eth_addr_zero;
          break;
  
      case MFF_ETH_DST:
          match->flow.dl_dst = eth_addr_zero;
          match->wc.masks.dl_dst = eth_addr_zero;
          break;
  
      case MFF_ETH_TYPE:
          match->flow.dl_type = htons(0);
          match->wc.masks.dl_type = htons(0);
          break;
  
      case MFF_VLAN_TCI:
          match_set_dl_tci_masked(match, htons(0), htons(0));
          break;
  
      case MFF_DL_VLAN:
      case MFF_VLAN_VID:
          match_set_any_vid(match);
          break;
  
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
          match_set_any_pcp(match);
          break;
  
      case MFF_MPLS_LABEL:
          match_set_any_mpls_label(match, 0);
          break;
  
      case MFF_MPLS_TC:
          match_set_any_mpls_tc(match, 0);
          break;
  
      case MFF_MPLS_BOS:
          match_set_any_mpls_bos(match, 0);
          break;
  
      case MFF_MPLS_TTL:
          match_set_any_mpls_ttl(match, 0);
          break;
  
      case MFF_IPV4_SRC:
      case MFF_ARP_SPA:
          match_set_nw_src_masked(match, htonl(0), htonl(0));
          break;
  
      case MFF_IPV4_DST:
      case MFF_ARP_TPA:
          match_set_nw_dst_masked(match, htonl(0), htonl(0));
          break;
  
      case MFF_IPV6_SRC:
          memset(&match->wc.masks.ipv6_src, 0, sizeof match->wc.masks.ipv6_src);
          memset(&match->flow.ipv6_src, 0, sizeof match->flow.ipv6_src);
          break;
  
      case MFF_IPV6_DST:
          memset(&match->wc.masks.ipv6_dst, 0, sizeof match->wc.masks.ipv6_dst);
          memset(&match->flow.ipv6_dst, 0, sizeof match->flow.ipv6_dst);
          break;
  
      case MFF_IPV6_LABEL:
          match->wc.masks.ipv6_label = htonl(0);
          match->flow.ipv6_label = htonl(0);
          break;
  
      case MFF_IP_PROTO:
          match->wc.masks.nw_proto = 0;
          match->flow.nw_proto = 0;
          break;
  
      case MFF_IP_DSCP:
      case MFF_IP_DSCP_SHIFTED:
          match->wc.masks.nw_tos &= ~IP_DSCP_MASK;
          match->flow.nw_tos &= ~IP_DSCP_MASK;
          break;
  
      case MFF_IP_ECN:
          match->wc.masks.nw_tos &= ~IP_ECN_MASK;
          match->flow.nw_tos &= ~IP_ECN_MASK;
          break;
  
      case MFF_IP_TTL:
          match->wc.masks.nw_ttl = 0;
          match->flow.nw_ttl = 0;
          break;
  
      case MFF_IP_FRAG:
          match->wc.masks.nw_frag &= ~FLOW_NW_FRAG_MASK;
          match->flow.nw_frag &= ~FLOW_NW_FRAG_MASK;
          break;
  
      case MFF_ARP_OP:
          match->wc.masks.nw_proto = 0;
          match->flow.nw_proto = 0;
          break;
  
      case MFF_ARP_SHA:
      case MFF_ND_SLL:
          match->flow.arp_sha = eth_addr_zero;
          match->wc.masks.arp_sha = eth_addr_zero;
          break;
  
      case MFF_ARP_THA:
      case MFF_ND_TLL:
          match->flow.arp_tha = eth_addr_zero;
          match->wc.masks.arp_tha = eth_addr_zero;
          break;
  
      case MFF_ND_RESERVED:
          match->wc.masks.igmp_group_ip4 = htonl(0);
          match->flow.igmp_group_ip4 = htonl(0);
          break;
  
      case MFF_TCP_SRC:
      case MFF_UDP_SRC:
      case MFF_SCTP_SRC:
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV6_TYPE:
          match->wc.masks.tp_src = htons(0);
          match->flow.tp_src = htons(0);
          break;
  
      case MFF_TCP_DST:
      case MFF_UDP_DST:
      case MFF_SCTP_DST:
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_CODE:
          match->wc.masks.tp_dst = htons(0);
          match->flow.tp_dst = htons(0);
          break;
  
      case MFF_TCP_FLAGS:
      case MFF_ND_OPTIONS_TYPE:
          match->wc.masks.tcp_flags = htons(0);
          match->flow.tcp_flags = htons(0);
          break;
  
      case MFF_ND_TARGET:
          memset(&match->wc.masks.nd_target, 0,
                 sizeof match->wc.masks.nd_target);
          memset(&match->flow.nd_target, 0, sizeof match->flow.nd_target);
          break;
  
      case MFF_NSH_FLAGS:
          MATCH_SET_FIELD_MASKED(match, nsh.flags, 0, 0);
          break;
      case MFF_NSH_TTL:
          MATCH_SET_FIELD_MASKED(match, nsh.ttl, 0, 0);
          break;
      case MFF_NSH_MDTYPE:
          MATCH_SET_FIELD_MASKED(match, nsh.mdtype, 0, 0);
          break;
      case MFF_NSH_NP:
          MATCH_SET_FIELD_MASKED(match, nsh.np, 0, 0);
          break;
      case MFF_NSH_SPI:
          match->wc.masks.nsh.path_hdr &= ~htonl(NSH_SPI_MASK);
          nsh_path_hdr_set_spi(&match->flow.nsh.path_hdr, htonl(0));
          break;
      case MFF_NSH_SI:
          match->wc.masks.nsh.path_hdr &= ~htonl(NSH_SI_MASK);
          nsh_path_hdr_set_si(&match->flow.nsh.path_hdr, 0);
          break;
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          MATCH_SET_FIELD_MASKED(match, nsh.context[mf->id - MFF_NSH_C1],
                                 htonl(0), htonl(0));
          break;
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /* Makes 'match' match field 'mf' with the specified 'value' and 'mask'.
   * 'value' specifies a value to match and 'mask' specifies a wildcard pattern,
   * with a 1-bit indicating that the corresponding value bit must match and a
   * 0-bit indicating a don't-care.
   *
   * If 'mask' is NULL or points to all-1-bits, then this call is equivalent to
   * mf_set_value(mf, value, match).  If 'mask' points to all-0-bits, then this
   * call is equivalent to mf_set_wild(mf, match).
   *
   * 'mask' must be a valid mask for 'mf' (see mf_is_mask_valid()).  The caller
   * is responsible for ensuring that 'match' meets 'mf''s prerequisites.
   *
   * If non-NULL, 'err_str' returns a malloc'ed string describing any errors
   * with the request or NULL if there is no error. The caller is reponsible
   * for freeing the string.
   *
   * Return a set of enum ofputil_protocol bits (as an uint32_t to avoid circular
   * dependency on enum ofputil_protocol definition) indicating which OpenFlow
   * protocol versions can support this functionality. */
  uint32_t
  mf_set(const struct mf_field *mf,
         const union mf_value *value, const union mf_value *mask,
         struct match *match, char **err_str)
  {
      if (!mask || is_all_ones(mask, mf->n_bytes)) {
          mf_set_value(mf, value, match, err_str);
          return mf->usable_protocols_exact;
      } else if (is_all_zeros(mask, mf->n_bytes) && !mf_is_tun_metadata(mf)) {
          /* Tunnel metadata matches on the existence of the field itself, so
           * it still needs to be encoded even if the value is wildcarded. */
          mf_set_wild(mf, match, err_str);
          return OFPUTIL_P_ANY;
      }
  
      if (err_str) {
          *err_str = NULL;
      }
  
      /* The cases where 'mask' is all-1-bits or all-0-bits were already handled
       * above[*], so the code below only needs to work for the remaining cases
       * of a nontrivial mask.
       *
       * [*] Except where the field is a tunnel metadata field and 'mask' is
       *     all-0-bits; see above. */
      switch (mf->id) {
      case MFF_CT_ZONE:
      case MFF_CT_NW_PROTO:
      case MFF_CT_NW_SRC:
      case MFF_CT_NW_DST:
      case MFF_CT_IPV6_SRC:
      case MFF_CT_IPV6_DST:
      case MFF_CT_TP_SRC:
      case MFF_CT_TP_DST:
      case MFF_RECIRC_ID:
      case MFF_PACKET_TYPE:
      case MFF_CONJ_ID:
      case MFF_IN_PORT:
      case MFF_IN_PORT_OXM:
      case MFF_ACTSET_OUTPUT:
      case MFF_SKB_PRIORITY:
      case MFF_ETH_TYPE:
      case MFF_DL_VLAN:
      case MFF_DL_VLAN_PCP:
      case MFF_VLAN_PCP:
      case MFF_MPLS_LABEL:
      case MFF_MPLS_TC:
      case MFF_MPLS_BOS:
      case MFF_MPLS_TTL:
      case MFF_IP_PROTO:
      case MFF_IP_TTL:
      case MFF_IP_DSCP:
      case MFF_IP_DSCP_SHIFTED:
      case MFF_IP_ECN:
      case MFF_ARP_OP:
      case MFF_ICMPV4_TYPE:
      case MFF_ICMPV4_CODE:
      case MFF_ICMPV6_TYPE:
      case MFF_ICMPV6_CODE:
      case MFF_ND_RESERVED:
      case MFF_ND_OPTIONS_TYPE:
          return OFPUTIL_P_NONE;
  
      case MFF_DP_HASH:
          match_set_dp_hash_masked(match, ntohl(value->be32), ntohl(mask->be32));
          break;
      case MFF_TUN_ID:
          match_set_tun_id_masked(match, value->be64, mask->be64);
          break;
      case MFF_TUN_SRC:
          match_set_tun_src_masked(match, value->be32, mask->be32);
          break;
      case MFF_TUN_DST:
          match_set_tun_dst_masked(match, value->be32, mask->be32);
          break;
      case MFF_TUN_IPV6_SRC:
          match_set_tun_ipv6_src_masked(match, &value->ipv6, &mask->ipv6);
          break;
      case MFF_TUN_IPV6_DST:
          match_set_tun_ipv6_dst_masked(match, &value->ipv6, &mask->ipv6);
          break;
      case MFF_TUN_FLAGS:
          match_set_tun_flags_masked(match, ntohs(value->be16), ntohs(mask->be16));
          break;
      case MFF_TUN_GBP_ID:
          match_set_tun_gbp_id_masked(match, value->be16, mask->be16);
          break;
      case MFF_TUN_GBP_FLAGS:
          match_set_tun_gbp_flags_masked(match, value->u8, mask->u8);
          break;
      case MFF_TUN_TTL:
          match_set_tun_ttl_masked(match, value->u8, mask->u8);
          break;
      case MFF_TUN_TOS:
          match_set_tun_tos_masked(match, value->u8, mask->u8);
          break;
      case MFF_TUN_ERSPAN_VER:
          match_set_tun_erspan_ver_masked(match, value->u8, mask->u8);
          break;
      case MFF_TUN_ERSPAN_IDX:
          match_set_tun_erspan_idx_masked(match, ntohl(value->be32),
                                          ntohl(mask->be32));
          break;
      case MFF_TUN_ERSPAN_DIR:
          match_set_tun_erspan_dir_masked(match, value->u8, mask->u8);
          break;
      case MFF_TUN_ERSPAN_HWID:
          match_set_tun_erspan_hwid_masked(match, value->u8, mask->u8);
          break;
      CASE_MFF_TUN_METADATA:
          tun_metadata_set_match(mf, value, mask, match, err_str);
          break;
  
      case MFF_METADATA:
          match_set_metadata_masked(match, value->be64, mask->be64);
          break;
  
      CASE_MFF_REGS:
          match_set_reg_masked(match, mf->id - MFF_REG0,
                               ntohl(value->be32), ntohl(mask->be32));
          break;
  
      CASE_MFF_XREGS:
          match_set_xreg_masked(match, mf->id - MFF_XREG0,
                                ntohll(value->be64), ntohll(mask->be64));
          break;
  
      CASE_MFF_XXREGS: {
          match_set_xxreg_masked(match, mf->id - MFF_XXREG0,
                  ntoh128(value->be128), ntoh128(mask->be128));
          break;
      }
  
      case MFF_PKT_MARK:
          match_set_pkt_mark_masked(match, ntohl(value->be32),
                                    ntohl(mask->be32));
          break;
  
      case MFF_CT_STATE:
          match_set_ct_state_masked(match, ntohl(value->be32), ntohl(mask->be32));
          break;
  
      case MFF_CT_MARK:
          match_set_ct_mark_masked(match, ntohl(value->be32), ntohl(mask->be32));
          break;
  
      case MFF_CT_LABEL:
          match_set_ct_label_masked(match, ntoh128(value->be128),
                                    ntoh128(mask->be128));
          break;
  
      case MFF_ETH_DST:
          match_set_dl_dst_masked(match, value->mac, mask->mac);
          break;
  
      case MFF_ETH_SRC:
          match_set_dl_src_masked(match, value->mac, mask->mac);
          break;
  
      case MFF_ARP_SHA:
      case MFF_ND_SLL:
          match_set_arp_sha_masked(match, value->mac, mask->mac);
          break;
  
      case MFF_ARP_THA:
      case MFF_ND_TLL:
          match_set_arp_tha_masked(match, value->mac, mask->mac);
          break;
  
      case MFF_VLAN_TCI:
          match_set_dl_tci_masked(match, value->be16, mask->be16);
          break;
  
      case MFF_VLAN_VID:
          match_set_vlan_vid_masked(match, value->be16, mask->be16);
          break;
  
      case MFF_IPV4_SRC:
          match_set_nw_src_masked(match, value->be32, mask->be32);
          break;
  
      case MFF_IPV4_DST:
          match_set_nw_dst_masked(match, value->be32, mask->be32);
          break;
  
      case MFF_IPV6_SRC:
          match_set_ipv6_src_masked(match, &value->ipv6, &mask->ipv6);
          break;
  
      case MFF_IPV6_DST:
          match_set_ipv6_dst_masked(match, &value->ipv6, &mask->ipv6);
          break;
  
      case MFF_IPV6_LABEL:
          if ((mask->be32 & htonl(IPV6_LABEL_MASK)) == htonl(IPV6_LABEL_MASK)) {
              mf_set_value(mf, value, match, err_str);
          } else {
              match_set_ipv6_label_masked(match, value->be32, mask->be32);
          }
          break;
  
      case MFF_ND_TARGET:
          match_set_nd_target_masked(match, &value->ipv6, &mask->ipv6);
          break;
  
      case MFF_IP_FRAG:
          match_set_nw_frag_masked(match, value->u8, mask->u8);
          break;
  
      case MFF_ARP_SPA:
          match_set_nw_src_masked(match, value->be32, mask->be32);
          break;
  
      case MFF_ARP_TPA:
          match_set_nw_dst_masked(match, value->be32, mask->be32);
          break;
  
      case MFF_TCP_SRC:
      case MFF_UDP_SRC:
      case MFF_SCTP_SRC:
          match_set_tp_src_masked(match, value->be16, mask->be16);
          break;
  
      case MFF_TCP_DST:
      case MFF_UDP_DST:
      case MFF_SCTP_DST:
          match_set_tp_dst_masked(match, value->be16, mask->be16);
          break;
  
      case MFF_TCP_FLAGS:
          match_set_tcp_flags_masked(match, value->be16, mask->be16);
          break;
  
      case MFF_NSH_FLAGS:
          MATCH_SET_FIELD_MASKED(match, nsh.flags, value->u8, mask->u8);
          break;
      case MFF_NSH_TTL:
          MATCH_SET_FIELD_MASKED(match, nsh.ttl, value->u8, mask->u8);
          break;
      case MFF_NSH_MDTYPE:
          MATCH_SET_FIELD_MASKED(match, nsh.mdtype, value->u8, mask->u8);
          break;
      case MFF_NSH_NP:
          MATCH_SET_FIELD_MASKED(match, nsh.np, value->u8, mask->u8);
          break;
      case MFF_NSH_SPI:
          match->wc.masks.nsh.path_hdr |= mask->be32;
          nsh_path_hdr_set_spi(&match->flow.nsh.path_hdr,
                               value->be32 & mask->be32);
          break;
      case MFF_NSH_SI:
          match->wc.masks.nsh.path_hdr |= htonl(mask->u8);
          nsh_path_hdr_set_si(&match->flow.nsh.path_hdr,
                               value->u8 & mask->u8);
          break;
      case MFF_NSH_C1:
      case MFF_NSH_C2:
      case MFF_NSH_C3:
      case MFF_NSH_C4:
          MATCH_SET_FIELD_MASKED(match, nsh.context[mf->id - MFF_NSH_C1],
                                 value->be32, mask->be32);
          break;
  
      case MFF_N_IDS:
      default:
          OVS_NOT_REACHED();
      }
  
      return ((mf->usable_protocols_bitwise == mf->usable_protocols_cidr
               || ip_is_cidr(mask->be32))
              ? mf->usable_protocols_cidr
              : mf->usable_protocols_bitwise);
  }
  
  /*zq*/
  uint32_t
  pof_mf_set(const struct mf_field *mf,
             const union mf_value *value, const union mf_value *mask,
             struct match_x *match, char **err_str)
  {
      if (!mask || is_all_ones(mask, mf->n_bytes)) {
          pof_mf_set_value(mf, value, match, err_str);
          return mf->usable_protocols_exact;
      } else if (is_all_zeros(mask, mf->n_bytes) && !mf_is_tun_metadata(mf)) {
          VLOG_INFO("+++++++++++zq pof_mf_set: all zeros ");
          /* Tunnel metadata matches on the existence of the field itself, so
           * it still needs to be encoded even if the value is wildcarded.
          mf_set_wild(mf, match, err_str);
          return OFPUTIL_P_ANY;*/
      }
  
      if (err_str) {
          *err_str = NULL;
      }
  
      /* VLOG_INFO("+++++++++++sqy pof_mf_set: before switch");*/
      switch (mf->id) {
          case MFF_FIELD_ID0:
              VLOG_INFO("+++++++++++zq pof_mf_set: MFF_FIELD_ID0");
              pof_match_set_field_id(match, mf->id - MFF_FIELD_ID0, value->be16);
              break;
          case MFF_FIELD_ID1:
          case MFF_FIELD_ID2:
          case MFF_FIELD_ID3:
          case MFF_FIELD_ID4:
          case MFF_FIELD_ID5:
          case MFF_FIELD_ID6:
          case MFF_FIELD_ID7:
              VLOG_INFO("+++++++++++zq pof_mf_set: MFF_FIELD_ID7");
              pof_match_set_field_id(match, mf->id - MFF_FIELD_ID0, value->be16);
              break;
  
          case MFF_OFFSET0:
          case MFF_OFFSET1:
          case MFF_OFFSET2:
          case MFF_OFFSET3:
          case MFF_OFFSET4:
          case MFF_OFFSET5:
          case MFF_OFFSET6:
          case MFF_OFFSET7:
              VLOG_INFO("+++++++++++zq pof_mf_set: MFF_OFFSET7");
              pof_match_set_offset(match, mf->id - MFF_OFFSET0, value->be16);
              break;
  
          case MFF_LENGTH0:
          case MFF_LENGTH1:
          case MFF_LENGTH2:
          case MFF_LENGTH3:
          case MFF_LENGTH4:
          case MFF_LENGTH5:
          case MFF_LENGTH6:
          case MFF_LENGTH7:
              VLOG_INFO("+++++++++++zq pof_mf_set: MFF_LENGTH7");
              pof_match_set_length(match, mf->id - MFF_LENGTH0, value->be16);
              break;
  
          case MFF_VALUE0:
          case MFF_VALUE1:
          case MFF_VALUE2:
          case MFF_VALUE3:
          case MFF_VALUE4:
          case MFF_VALUE5:
          case MFF_VALUE6:
          case MFF_VALUE7:
              VLOG_INFO("+++++++++++zq pof_mf_set: MFF_VALUE7");
              pof_match_set_value_masked(match, mf->id - MFF_VALUE0, &value->ipv6, &mask->ipv6);
              break;
  
          default:
              OVS_NOT_REACHED();
      }
  
      return ((mf->usable_protocols_bitwise == mf->usable_protocols_cidr
               || ip_is_cidr(mask->be32))
              ? mf->usable_protocols_cidr
              : mf->usable_protocols_bitwise);
  
  }
  
  static enum ofperr
  mf_check__(const struct mf_subfield *sf, const struct match *match,
             const char *type)
  {
      if (!sf->field) {
          VLOG_WARN_RL(&rl, "unknown %s field", type);
          return OFPERR_OFPBAC_BAD_SET_TYPE;
      } else if (!sf->n_bits) {
          VLOG_WARN_RL(&rl, "zero bit %s field %s", type, sf->field->name);
          return OFPERR_OFPBAC_BAD_SET_LEN;
      } else if (sf->ofs >= sf->field->n_bits) {
          VLOG_WARN_RL(&rl, "bit offset %d exceeds %d-bit width of %s field %s",
                       sf->ofs, sf->field->n_bits, type, sf->field->name);
          return OFPERR_OFPBAC_BAD_SET_LEN;
      } else if (sf->ofs + sf->n_bits > sf->field->n_bits) {
          VLOG_WARN_RL(&rl, "bit offset %d and width %d exceeds %d-bit width "
                       "of %s field %s", sf->ofs, sf->n_bits,
                       sf->field->n_bits, type, sf->field->name);
          return OFPERR_OFPBAC_BAD_SET_LEN;
      } else if (match && !mf_are_match_prereqs_ok(sf->field, match)) {
          VLOG_WARN_RL(&rl, "%s field %s lacks correct prerequisites",
                       type, sf->field->name);
          return OFPERR_OFPBAC_MATCH_INCONSISTENT;
      } else {
          return 0;
      }
  }
  
  /* Sets all the bits in 'sf' to 1 within 'wc', if 'wc' is nonnull. */
  static void
  unwildcard_subfield(const struct mf_subfield *sf, struct flow_wildcards *wc)
  {
      if (wc) {
          union mf_value mask;
  
          memset(&mask, 0, sizeof mask);
          bitwise_one(&mask, sf->field->n_bytes, sf->ofs, sf->n_bits);
          mf_mask_field_masked(sf->field, &mask, wc);
      }
  }
  
  /* Copies 'src' into 'dst' within 'flow', and sets all the bits in 'src' and
   * 'dst' to 1s in 'wc', if 'wc' is nonnull.
   *
   * 'src' and 'dst' may overlap. */
  void
  mf_subfield_copy(const struct mf_subfield *src,
                   const struct mf_subfield *dst,
                   struct flow *flow, struct flow_wildcards *wc)
  {
      ovs_assert(src->n_bits == dst->n_bits);
      if (mf_are_prereqs_ok(dst->field, flow, wc)
          && mf_are_prereqs_ok(src->field, flow, wc)) {
          unwildcard_subfield(src, wc);
          unwildcard_subfield(dst, wc);
  
          union mf_value src_value;
          union mf_value dst_value;
          mf_get_value(dst->field, flow, &dst_value);
          mf_get_value(src->field, flow, &src_value);
          bitwise_copy(&src_value, src->field->n_bytes, src->ofs,
                       &dst_value, dst->field->n_bytes, dst->ofs,
                       src->n_bits);
          mf_set_flow_value(dst->field, &dst_value, flow);
      }
  }
  
  /* Swaps the bits in 'src' and 'dst' within 'flow', and sets all the bits in
   * 'src' and 'dst' to 1s in 'wc', if 'wc' is nonnull.
   *
   * 'src' and 'dst' may overlap. */
  void
  mf_subfield_swap(const struct mf_subfield *a,
                   const struct mf_subfield *b,
                   struct flow *flow, struct flow_wildcards *wc)
  {
      ovs_assert(a->n_bits == b->n_bits);
      if (mf_are_prereqs_ok(a->field, flow, wc)
          && mf_are_prereqs_ok(b->field, flow, wc)) {
          unwildcard_subfield(a, wc);
          unwildcard_subfield(b, wc);
  
          union mf_value a_value;
          union mf_value b_value;
          mf_get_value(a->field, flow, &a_value);
          mf_get_value(b->field, flow, &b_value);
          union mf_value b2_value = b_value;
  
          /* Copy 'a' into 'b'. */
          bitwise_copy(&a_value, a->field->n_bytes, a->ofs,
                       &b_value, b->field->n_bytes, b->ofs,
                       a->n_bits);
          mf_set_flow_value(b->field, &b_value, flow);
  
          /* Copy original 'b' into 'a'. */
          bitwise_copy(&b2_value, b->field->n_bytes, b->ofs,
                       &a_value, a->field->n_bytes, a->ofs,
                       b->n_bits);
          mf_set_flow_value(a->field, &a_value, flow);
      }
  }
  
  /* Checks whether 'sf' is valid for reading a subfield out of 'flow'.  Returns
   * 0 if so, otherwise an OpenFlow error code (e.g. as returned by
   * ofp_mkerr()).  */
  enum ofperr
  mf_check_src(const struct mf_subfield *sf, const struct match *match)
  {
      return mf_check__(sf, match, "source");
  }
  
  /* Checks whether 'sf' is valid for writing a subfield into 'flow'.  Returns 0
   * if so, otherwise an OpenFlow error code (e.g. as returned by
   * ofp_mkerr()). */
  enum ofperr
  mf_check_dst(const struct mf_subfield *sf, const struct match *match)
  {
      int error = mf_check__(sf, match, "destination");
      if (!error && !sf->field->writable) {
          VLOG_WARN_RL(&rl, "destination field %s is not writable",
                       sf->field->name);
          return OFPERR_OFPBAC_BAD_SET_ARGUMENT;
      }
      return error;
  }
  
  /* Copies the value and wildcard bit pattern for 'mf' from 'match' into the
   * 'value' and 'mask', respectively. */
  void
  mf_get(const struct mf_field *mf, const struct match *match,
         union mf_value *value, union mf_value *mask)
  {
      mf_get_value(mf, &match->flow, value);
      mf_get_mask(mf, &match->wc, mask);
  }
  
  static char *
  mf_from_integer_string(const struct mf_field *mf, const char *s,
                         uint8_t *valuep, uint8_t *maskp)
  {
      char *tail;
      const char *err_str = "";
      int err;
  
      err = parse_int_string(s, valuep, mf->n_bytes, &tail);
      if (err || (*tail != '\0' && *tail != '/')) {
          err_str = "value";
          goto syntax_error;
      }
  
      if (*tail == '/') {
          err = parse_int_string(tail + 1, maskp, mf->n_bytes, &tail);
          if (err || *tail != '\0') {
              err_str = "mask";
              goto syntax_error;
          }
      } else {
          memset(maskp, 0xff, mf->n_bytes);
      }
  
      return NULL;
  
  syntax_error:
      if (err == ERANGE) {
          return xasprintf("%s: %s too large for %u-byte field %s",
                           s, err_str, mf->n_bytes, mf->name);
      } else {
          return xasprintf("%s: bad syntax for %s %s", s, mf->name, err_str);
      }
  }
  
  static char *
  mf_from_packet_type_string(const char *s, ovs_be32 *packet_type)
  {
      char *tail;
      const char *err_str = "";
      int err;
  
      if (*s != '(') {
          err_str = "missing '('";
          goto syntax_error;
      }
      s++;
      err = parse_int_string(s, (uint8_t *)packet_type, 2, &tail);
      if (err) {
          err_str = "ns";
          goto syntax_error;
      }
      if (*tail != ',') {
          err_str = "missing ','";
          goto syntax_error;
      }
      s = tail + 1;
      err = parse_int_string(s, ((uint8_t *)packet_type) + 2, 2, &tail);
      if (err) {
          err_str = "ns_type";
          goto syntax_error;
      }
      if (*tail != ')') {
          err_str = "missing ')'";
          goto syntax_error;
      }
  
      return NULL;
  
  syntax_error:
      return xasprintf("%s: bad syntax for packet type %s", s, err_str);
  }
  
  static char *
  mf_from_ethernet_string(const struct mf_field *mf, const char *s,
                          struct eth_addr *mac, struct eth_addr *mask)
  {
      int n;
  
      ovs_assert(mf->n_bytes == ETH_ADDR_LEN);
  
      n = -1;
      if (ovs_scan(s, ETH_ADDR_SCAN_FMT"%n", ETH_ADDR_SCAN_ARGS(*mac), &n)
          && n == strlen(s)) {
          *mask = eth_addr_exact;
          return NULL;
      }
  
      n = -1;
      if (ovs_scan(s, ETH_ADDR_SCAN_FMT"/"ETH_ADDR_SCAN_FMT"%n",
                   ETH_ADDR_SCAN_ARGS(*mac), ETH_ADDR_SCAN_ARGS(*mask), &n)
          && n == strlen(s)) {
          return NULL;
      }
  
      return xasprintf("%s: invalid Ethernet address", s);
  }
  
  static char *
  mf_from_ipv4_string(const struct mf_field *mf, const char *s,
                      ovs_be32 *ip, ovs_be32 *mask)
  {
      ovs_assert(mf->n_bytes == sizeof *ip);
      return ip_parse_masked(s, ip, mask);
  }
  
  static char *
  mf_from_ipv6_string(const struct mf_field *mf, const char *s,
                      struct in6_addr *ipv6, struct in6_addr *mask)
  {
      ovs_assert(mf->n_bytes == sizeof *ipv6);
      return ipv6_parse_masked(s, ipv6, mask);
  }
  
  static char *
  mf_from_ofp_port_string(const struct mf_field *mf, const char *s,
                          const struct ofputil_port_map *port_map,
                          ovs_be16 *valuep, ovs_be16 *maskp)
  {
      ofp_port_t port;
  
      ovs_assert(mf->n_bytes == sizeof(ovs_be16));
  
      if (ofputil_port_from_string(s, port_map, &port)) {
          *valuep = htons(ofp_to_u16(port));
          *maskp = OVS_BE16_MAX;
          return NULL;
      }
      return xasprintf("%s: invalid or unknown port for %s", s, mf->name);
  }
  
  static char *
  mf_from_ofp_port_string32(const struct mf_field *mf, const char *s,
                            const struct ofputil_port_map *port_map,
                            ovs_be32 *valuep, ovs_be32 *maskp)
  {
      ofp_port_t port;
  
      ovs_assert(mf->n_bytes == sizeof(ovs_be32));
      if (ofputil_port_from_string(s, port_map, &port)) {
          *valuep = ofputil_port_to_ofp11(port);
          *maskp = OVS_BE32_MAX;
          return NULL;
      }
      return xasprintf("%s: port value out of range for %s", s, mf->name);
  }
  
  struct frag_handling {
      const char *name;
      uint8_t mask;
      uint8_t value;
  };
  
  static const struct frag_handling all_frags[] = {
  #define A FLOW_NW_FRAG_ANY
  #define L FLOW_NW_FRAG_LATER
      /* name               mask  value */
  
      { "no",               A|L,  0     },
      { "first",            A|L,  A     },
      { "later",            A|L,  A|L   },
  
      { "no",               A,    0     },
      { "yes",              A,    A     },
  
      { "not_later",        L,    0     },
      { "later",            L,    L     },
  #undef A
  #undef L
  };
  
  static char *
  mf_from_frag_string(const char *s, uint8_t *valuep, uint8_t *maskp)
  {
      const struct frag_handling *h;
  
      for (h = all_frags; h < &all_frags[ARRAY_SIZE(all_frags)]; h++) {
          if (!strcasecmp(s, h->name)) {
              /* We force the upper bits of the mask on to make mf_parse_value()
               * happy (otherwise it will never think it's an exact match.) */
              *maskp = h->mask | ~FLOW_NW_FRAG_MASK;
              *valuep = h->value;
              return NULL;
          }
      }
  
      return xasprintf("%s: unknown fragment type (valid types are \"no\", "
                       "\"yes\", \"first\", \"later\", \"not_later\"", s);
  }
  
  static char *
  parse_mf_flags(const char *s, const char *(*bit_to_string)(uint32_t),
                 const char *field_name, ovs_be16 *flagsp, ovs_be16 allowed,
                 ovs_be16 *maskp)
  {
      int err;
      char *err_str;
      uint32_t flags, mask;
  
      err = parse_flags(s, bit_to_string, '\0', field_name, &err_str,
                        &flags, ntohs(allowed), maskp ? &mask : NULL);
      if (err < 0) {
          return err_str;
      }
  
      *flagsp = htons(flags);
      if (maskp) {
          *maskp = htons(mask);
      }
  
      return NULL;
  }
  
  static char *
  mf_from_tcp_flags_string(const char *s, ovs_be16 *flagsp, ovs_be16 *maskp)
  {
      return parse_mf_flags(s, packet_tcp_flag_to_string, "TCP", flagsp,
                            TCP_FLAGS_BE16(OVS_BE16_MAX), maskp);
  }
  
  static char *
  mf_from_tun_flags_string(const char *s, ovs_be16 *flagsp, ovs_be16 *maskp)
  {
      return parse_mf_flags(s, flow_tun_flag_to_string, "tunnel", flagsp,
                            htons(FLOW_TNL_PUB_F_MASK), maskp);
  }
  
  static char *
  mf_from_ct_state_string(const char *s, ovs_be32 *flagsp, ovs_be32 *maskp)
  {
      int err;
      char *err_str;
      uint32_t flags, mask;
  
      err = parse_flags(s, ct_state_to_string, '\0', "ct_state", &err_str,
                        &flags, CS_SUPPORTED_MASK, maskp ? &mask : NULL);
      if (err < 0) {
          return err_str;
      }
  
      *flagsp = htonl(flags);
      if (maskp) {
          *maskp = htonl(mask);
      }
  
      return NULL;
  }
  
  /* Parses 's', a string value for field 'mf', into 'value' and 'mask'.  Returns
   * NULL if successful, otherwise a malloc()'d string describing the error. */
  char *
  mf_parse(const struct mf_field *mf, const char *s,
           const struct ofputil_port_map *port_map,
           union mf_value *value, union mf_value *mask)
  {
      char *error;
  
      if (!strcmp(s, "*")) {
          memset(value, 0, mf->n_bytes);
          memset(mask, 0, mf->n_bytes);
          return NULL;
      }
  
      switch (mf->string) {
      case MFS_DECIMAL:
      case MFS_HEXADECIMAL:
          error = mf_from_integer_string(mf, s,
                                         (uint8_t *) value, (uint8_t *) mask);
          break;
  
      case MFS_CT_STATE:
          ovs_assert(mf->n_bytes == sizeof(ovs_be32));
          error = mf_from_ct_state_string(s, &value->be32, &mask->be32);
          break;
  
      case MFS_ETHERNET:
          error = mf_from_ethernet_string(mf, s, &value->mac, &mask->mac);
          break;
  
      case MFS_IPV4:
          error = mf_from_ipv4_string(mf, s, &value->be32, &mask->be32);
          break;
  
      case MFS_IPV6:
          error = mf_from_ipv6_string(mf, s, &value->ipv6, &mask->ipv6);
          break;
  
      case MFS_OFP_PORT:
          error = mf_from_ofp_port_string(mf, s, port_map,
                                          &value->be16, &mask->be16);
          break;
  
      case MFS_OFP_PORT_OXM:
          error = mf_from_ofp_port_string32(mf, s, port_map,
                                            &value->be32, &mask->be32);
          break;
  
      case MFS_FRAG:
          error = mf_from_frag_string(s, &value->u8, &mask->u8);
          break;
  
      case MFS_TNL_FLAGS:
          ovs_assert(mf->n_bytes == sizeof(ovs_be16));
          error = mf_from_tun_flags_string(s, &value->be16, &mask->be16);
          break;
  
      case MFS_TCP_FLAGS:
          ovs_assert(mf->n_bytes == sizeof(ovs_be16));
          error = mf_from_tcp_flags_string(s, &value->be16, &mask->be16);
          break;
  
      case MFS_PACKET_TYPE:
          ovs_assert(mf->n_bytes == sizeof(ovs_be32));
          error = mf_from_packet_type_string(s, &value->be32);
          mask->be32 = OVS_BE32_MAX;
          break;
  
      default:
          OVS_NOT_REACHED();
      }
  
      if (!error && !mf_is_mask_valid(mf, mask)) {
          error = xasprintf("%s: invalid mask for field %s", s, mf->name);
      }
      return error;
  }
  
  /* Parses 's', a string value for field 'mf', into 'value'.  Returns NULL if
   * successful, otherwise a malloc()'d string describing the error. */
  char *
  mf_parse_value(const struct mf_field *mf, const char *s,
                 const struct ofputil_port_map *port_map, union mf_value *value)
  {
      union mf_value mask;
      char *error;
  
      error = mf_parse(mf, s, port_map, value, &mask);
      if (error) {
          return error;
      }
  
      if (!is_all_ones((const uint8_t *) &mask, mf->n_bytes)) {
          return xasprintf("%s: wildcards not allowed here", s);
      }
      return NULL;
  }
  
  static void
  mf_format_integer_string(const struct mf_field *mf, const uint8_t *valuep,
                           const uint8_t *maskp, struct ds *s)
  {
      if (mf->string == MFS_HEXADECIMAL) {
          ds_put_hex(s, valuep, mf->n_bytes);
      } else {
          unsigned long long int integer = 0;
          int i;
  
          ovs_assert(mf->n_bytes <= 8);
          for (i = 0; i < mf->n_bytes; i++) {
              integer = (integer << 8) | valuep[i];
          }
          ds_put_format(s, "%lld", integer);
      }
  
      if (maskp) {
          /* I guess we could write the mask in decimal for MFS_DECIMAL but I'm
           * not sure that that a bit-mask written in decimal is ever easier to
           * understand than the same bit-mask written in hexadecimal. */
          ds_put_char(s, '/');
          ds_put_hex(s, maskp, mf->n_bytes);
      }
  }
  
  static void
  mf_format_frag_string(uint8_t value, uint8_t mask, struct ds *s)
  {
      const struct frag_handling *h;
  
      mask &= FLOW_NW_FRAG_MASK;
      value &= mask;
  
      for (h = all_frags; h < &all_frags[ARRAY_SIZE(all_frags)]; h++) {
          if (value == h->value && mask == h->mask) {
              ds_put_cstr(s, h->name);
              return;
          }
      }
      ds_put_cstr(s, "<error>");
  }
  
  static void
  mf_format_tnl_flags_string(ovs_be16 value, ovs_be16 mask, struct ds *s)
  {
      format_flags_masked(s, NULL, flow_tun_flag_to_string, ntohs(value),
                          ntohs(mask) & FLOW_TNL_PUB_F_MASK, FLOW_TNL_PUB_F_MASK);
  }
  
  static void
  mf_format_tcp_flags_string(ovs_be16 value, ovs_be16 mask, struct ds *s)
  {
      format_flags_masked(s, NULL, packet_tcp_flag_to_string, ntohs(value),
                          TCP_FLAGS(mask), TCP_FLAGS(OVS_BE16_MAX));
  }
  
  static void
  mf_format_ct_state_string(ovs_be32 value, ovs_be32 mask, struct ds *s)
  {
      format_flags_masked(s, NULL, ct_state_to_string, ntohl(value),
                          ntohl(mask), UINT16_MAX);
  }
  
  static void
  mf_format_packet_type_string(ovs_be32 value, ovs_be32 mask, struct ds *s)
  {
      format_packet_type_masked(s, value, mask);
  }
  
  /* Appends to 's' a string representation of field 'mf' whose value is in
   * 'value' and 'mask'.  'mask' may be NULL to indicate an exact match. */
  void
  mf_format(const struct mf_field *mf,
            const union mf_value *value, const union mf_value *mask,
            const struct ofputil_port_map *port_map,
            struct ds *s)
  {
      if (mask) {
          if (is_all_zeros(mask, mf->n_bytes)) {
              ds_put_cstr(s, "ANY");
              return;
          } else if (is_all_ones(mask, mf->n_bytes)) {
              mask = NULL;
          }
      }
  
      switch (mf->string) {
      case MFS_OFP_PORT_OXM:
          if (!mask) {
              ofp_port_t port;
              ofputil_port_from_ofp11(value->be32, &port);
              ofputil_format_port(port, port_map, s);
              break;
          }
          /* fall through */
      case MFS_OFP_PORT:
          if (!mask) {
              ofputil_format_port(u16_to_ofp(ntohs(value->be16)), port_map, s);
              break;
          }
          /* fall through */
      case MFS_DECIMAL:
      case MFS_HEXADECIMAL:
          mf_format_integer_string(mf, (uint8_t *) value, (uint8_t *) mask, s);
          break;
  
      case MFS_CT_STATE:
          mf_format_ct_state_string(value->be32,
                                    mask ? mask->be32 : OVS_BE32_MAX, s);
          break;
  
      case MFS_ETHERNET:
          eth_format_masked(value->mac, mask ? &mask->mac : NULL, s);
          break;
  
      case MFS_IPV4:
          ip_format_masked(value->be32, mask ? mask->be32 : OVS_BE32_MAX, s);
          break;
  
      case MFS_IPV6:
          ipv6_format_masked(&value->ipv6, mask ? &mask->ipv6 : NULL, s);
          break;
  
      case MFS_FRAG:
          mf_format_frag_string(value->u8, mask ? mask->u8 : UINT8_MAX, s);
          break;
  
      case MFS_TNL_FLAGS:
          mf_format_tnl_flags_string(value->be16,
                                     mask ? mask->be16 : OVS_BE16_MAX, s);
          break;
  
      case MFS_TCP_FLAGS:
          mf_format_tcp_flags_string(value->be16,
                                     mask ? mask->be16 : OVS_BE16_MAX, s);
          break;
  
      case MFS_PACKET_TYPE:
          mf_format_packet_type_string(value->be32,
                                       mask ? mask->be32 : OVS_BE32_MAX, s);
          break;
  
      default:
          OVS_NOT_REACHED();
      }
  }
  
  /* Makes subfield 'sf' within 'flow' exactly match the 'sf->n_bits'
   * least-significant bits in 'x'.
   */
  void
  mf_write_subfield_flow(const struct mf_subfield *sf,
                         const union mf_subvalue *x, struct flow *flow)
  {
      const struct mf_field *field = sf->field;
      union mf_value value;
  
      mf_get_value(field, flow, &value);
      bitwise_copy(x, sizeof *x, 0, &value, field->n_bytes,
                   sf->ofs, sf->n_bits);
      mf_set_flow_value(field, &value, flow);
  }
  
  /* Makes subfield 'sf' within 'match' exactly match the 'sf->n_bits'
   * least-significant bits in 'x'.
   */
  void
  mf_write_subfield(const struct mf_subfield *sf, const union mf_subvalue *x,
                    struct match *match)
  {
      const struct mf_field *field = sf->field;
      union mf_value value, mask;
  
      mf_get(field, match, &value, &mask);
      bitwise_copy(x, sizeof *x, 0, &value, field->n_bytes, sf->ofs, sf->n_bits);
      bitwise_one (                 &mask,  field->n_bytes, sf->ofs, sf->n_bits);
      mf_set(field, &value, &mask, match, NULL);
  }
  
  void
  mf_write_subfield_value(const struct mf_subfield *sf, const void *src,
                          struct match *match)
  {
      const struct mf_field *field = sf->field;
      union mf_value value, mask;
      unsigned int size = DIV_ROUND_UP(sf->n_bits, 8);
  
      mf_get(field, match, &value, &mask);
      bitwise_copy(src, size, 0, &value, field->n_bytes, sf->ofs, sf->n_bits);
      bitwise_one (              &mask,  field->n_bytes, sf->ofs, sf->n_bits);
      mf_set(field, &value, &mask, match, NULL);
  }
  
  /* 'v' and 'm' correspond to values of 'field'.  This function copies them into
   * 'match' in the correspond positions. */
  void
  mf_mask_subfield(const struct mf_field *field,
                   const union mf_subvalue *v,
                   const union mf_subvalue *m,
                   struct match *match)
  {
      union mf_value value, mask;
  
      mf_get(field, match, &value, &mask);
      bitwise_copy(v, sizeof *v, 0, &value, field->n_bytes, 0, field->n_bits);
      bitwise_copy(m, sizeof *m, 0, &mask,  field->n_bytes, 0, field->n_bits);
      mf_set(field, &value, &mask, match, NULL);
  }
  
  /* Initializes 'x' to the value of 'sf' within 'flow'.  'sf' must be valid for
   * reading 'flow', e.g. as checked by mf_check_src(). */
  void
  mf_read_subfield(const struct mf_subfield *sf, const struct flow *flow,
                   union mf_subvalue *x)
  {
      union mf_value value;
  
      mf_get_value(sf->field, flow, &value);
  
      memset(x, 0, sizeof *x);
      bitwise_copy(&value, sf->field->n_bytes, sf->ofs,
                   x, sizeof *x, 0,
                   sf->n_bits);
  }
  
  /* Returns the value of 'sf' within 'flow'.  'sf' must be valid for reading
   * 'flow', e.g. as checked by mf_check_src() and sf->n_bits must be 64 or
   * less. */
  uint64_t
  mf_get_subfield(const struct mf_subfield *sf, const struct flow *flow)
  {
      union mf_value value;
  
      mf_get_value(sf->field, flow, &value);
      return bitwise_get(&value, sf->field->n_bytes, sf->ofs, sf->n_bits);
  }
  
  void
  mf_format_subvalue(const union mf_subvalue *subvalue, struct ds *s)
  {
      ds_put_hex(s, subvalue->u8, sizeof subvalue->u8);
  }
  
  void
  field_array_set(enum mf_field_id id, const union mf_value *value,
                  struct field_array *fa)
  {
      size_t i, offset = 0;
  
      ovs_assert(id < MFF_N_IDS);
  
      /* Find the spot for 'id'. */
      BITMAP_FOR_EACH_1 (i, id, fa->used.bm) {
          offset += mf_from_id(i)->n_bytes;
      }
  
      size_t value_size = mf_from_id(id)->n_bytes;
  
      /* make room if necessary. */
      if (!bitmap_is_set(fa->used.bm, id)) {
          fa->values = xrealloc(fa->values, fa->values_size + value_size);
          /* Move remainder forward, if any. */
          if (offset < fa->values_size) {
              memmove(fa->values + offset + value_size, fa->values + offset,
                      fa->values_size - offset);
          }
          fa->values_size += value_size;
      }
      bitmap_set1(fa->used.bm, id);
  
      memcpy(fa->values + offset, value, value_size);
  }
  
  /* A wrapper for variable length mf_fields that is maintained by
   * struct vl_mff_map.*/
  struct vl_mf_field {
      struct mf_field mf;
      struct ovs_refcount ref_cnt;
      struct cmap_node cmap_node; /* In ofproto->vl_mff_map->cmap. */
  };
  
  static inline uint32_t
  mf_field_hash(uint32_t key)
  {
      return hash_int(key, 0);
  }
  
  static void
  vmf_delete(struct vl_mf_field *vmf)
  {
      if (ovs_refcount_unref(&vmf->ref_cnt) == 1) {
          /* Postpone as this function is typically called immediately
           * after removing from cmap. */
          ovsrcu_postpone(free, vmf);
      } else {
          VLOG_WARN_RL(&rl,
                       "Attempted to delete VMF %s but refcount is nonzero!",
                       vmf->mf.name);
      }
  }
  
  enum ofperr
  mf_vl_mff_map_clear(struct vl_mff_map *vl_mff_map, bool force)
      OVS_REQUIRES(vl_mff_map->mutex)
  {
      struct vl_mf_field *vmf;
  
      if (!force) {
          CMAP_FOR_EACH (vmf, cmap_node, &vl_mff_map->cmap) {
              if (ovs_refcount_read(&vmf->ref_cnt) != 1) {
                  return OFPERR_NXTTMFC_INVALID_TLV_DEL;
              }
          }
      }
  
      CMAP_FOR_EACH (vmf, cmap_node, &vl_mff_map->cmap) {
          cmap_remove(&vl_mff_map->cmap, &vmf->cmap_node,
                      mf_field_hash(vmf->mf.id));
          vmf_delete(vmf);
      }
  
      return 0;
  }
  
  static struct vl_mf_field *
  mf_get_vl_mff__(uint32_t id, const struct vl_mff_map *vl_mff_map)
  {
      struct vl_mf_field *vmf;
  
      CMAP_FOR_EACH_WITH_HASH (vmf, cmap_node, mf_field_hash(id),
                               &vl_mff_map->cmap) {
          if (vmf->mf.id == id) {
              return vmf;
          }
      }
  
      return NULL;
  }
  
  /* If 'mff' is a variable length field, looks up 'vl_mff_map', returns a
   * pointer to the variable length meta-flow field corresponding to 'mff'.
   * Returns NULL if no mapping is existed for 'mff'. */
  const struct mf_field *
  mf_get_vl_mff(const struct mf_field *mff,
                const struct vl_mff_map *vl_mff_map)
  {
      if (mff && mff->variable_len && vl_mff_map) {
          return &mf_get_vl_mff__(mff->id, vl_mff_map)->mf;
      }
  
      return NULL;
  }
  
  static enum ofperr
  mf_vl_mff_map_del(struct vl_mff_map *vl_mff_map,
                    const struct ofputil_tlv_table_mod *ttm, bool force)
      OVS_REQUIRES(vl_mff_map->mutex)
  {
      struct ofputil_tlv_map *tlv_map;
      struct vl_mf_field *vmf;
      unsigned int idx;
  
      if (!force) {
          LIST_FOR_EACH (tlv_map, list_node, &ttm->mappings) {
              idx = MFF_TUN_METADATA0 + tlv_map->index;
              if (idx >= MFF_TUN_METADATA0 + TUN_METADATA_NUM_OPTS) {
                  return OFPERR_NXTTMFC_BAD_FIELD_IDX;
              }
  
              vmf = mf_get_vl_mff__(idx, vl_mff_map);
              if (vmf && ovs_refcount_read(&vmf->ref_cnt) != 1) {
                  return OFPERR_NXTTMFC_INVALID_TLV_DEL;
              }
          }
      }
  
      LIST_FOR_EACH (tlv_map, list_node, &ttm->mappings) {
          idx = MFF_TUN_METADATA0 + tlv_map->index;
          if (idx >= MFF_TUN_METADATA0 + TUN_METADATA_NUM_OPTS) {
              return OFPERR_NXTTMFC_BAD_FIELD_IDX;
          }
  
          vmf = mf_get_vl_mff__(idx, vl_mff_map);
          if (vmf) {
              cmap_remove(&vl_mff_map->cmap, &vmf->cmap_node,
                          mf_field_hash(idx));
              vmf_delete(vmf);
          }
      }
  
      return 0;
  }
  
  static enum ofperr
  mf_vl_mff_map_add(struct vl_mff_map *vl_mff_map,
                    const struct ofputil_tlv_table_mod *ttm)
      OVS_REQUIRES(vl_mff_map->mutex)
  {
      struct ofputil_tlv_map *tlv_map;
      struct vl_mf_field *vmf;
      unsigned int idx;
  
      LIST_FOR_EACH (tlv_map, list_node, &ttm->mappings) {
          idx = MFF_TUN_METADATA0 + tlv_map->index;
          if (idx >= MFF_TUN_METADATA0 + TUN_METADATA_NUM_OPTS) {
              return OFPERR_NXTTMFC_BAD_FIELD_IDX;
          }
  
          vmf = xmalloc(sizeof *vmf);
          vmf->mf = mf_fields[idx];
          vmf->mf.n_bytes = tlv_map->option_len;
          vmf->mf.n_bits = tlv_map->option_len * 8;
          vmf->mf.mapped = true;
          ovs_refcount_init(&vmf->ref_cnt);
  
          cmap_insert(&vl_mff_map->cmap, &vmf->cmap_node,
                      mf_field_hash(idx));
      }
  
      return 0;
  }
  
  /* Updates the tun_metadata mf_field in 'vl_mff_map' according to 'ttm'.
   * This function must be invoked after tun_metadata_table_mod().
   * Returns OFPERR_NXTTMFC_BAD_FIELD_IDX, if the index for the vl_mf_field is
   * invalid.
   * Returns OFPERR_NXTTMFC_INVALID_TLV_DEL, if 'ttm' tries to delete an
   * vl_mf_field that is still used by any active flow.*/
  enum ofperr
  mf_vl_mff_map_mod_from_tun_metadata(struct vl_mff_map *vl_mff_map,
                                      const struct ofputil_tlv_table_mod *ttm)
      OVS_REQUIRES(vl_mff_map->mutex)
  {
      switch (ttm->command) {
      case NXTTMC_ADD:
          return mf_vl_mff_map_add(vl_mff_map, ttm);
  
      case NXTTMC_DELETE:
          return mf_vl_mff_map_del(vl_mff_map, ttm, false);
  
      case NXTTMC_CLEAR:
          return mf_vl_mff_map_clear(vl_mff_map, false);
  
      default:
          OVS_NOT_REACHED();
      }
  
      return 0;
  }
  
  /* Returns true if a variable length meta-flow field 'mff' is not mapped in
   * the 'vl_mff_map'. */
  bool
  mf_vl_mff_invalid(const struct mf_field *mff, const struct vl_mff_map *map)
  {
      return map && mff && mff->variable_len && !mff->mapped;
  }
  
  void
  mf_vl_mff_set_tlv_bitmap(const struct mf_field *mff, uint64_t *tlv_bitmap)
  {
      if (mff && mff->mapped) {
          ovs_assert(mf_is_tun_metadata(mff));
          ULLONG_SET1(*tlv_bitmap, mff->id - MFF_TUN_METADATA0);
      }
  }
  
  static void
  mf_vl_mff_ref_cnt_mod(const struct vl_mff_map *map, uint64_t tlv_bitmap,
                        bool ref)
  {
      struct vl_mf_field *vmf;
      int i;
  
      if (map) {
          ULLONG_FOR_EACH_1 (i, tlv_bitmap) {
              vmf = mf_get_vl_mff__(i + MFF_TUN_METADATA0, map);
              if (vmf) {
                  if (ref) {
                      ovs_refcount_ref(&vmf->ref_cnt);
                  } else {
                      ovs_refcount_unref(&vmf->ref_cnt);
                  }
              } else {
                  VLOG_WARN("Invalid TLV index %d.", i);
              }
          }
      }
  }
  
  void
  mf_vl_mff_ref(const struct vl_mff_map *map, uint64_t tlv_bitmap)
  {
      mf_vl_mff_ref_cnt_mod(map, tlv_bitmap, true);
  }
  
  void
  mf_vl_mff_unref(const struct vl_mff_map *map, uint64_t tlv_bitmap)
  {
      mf_vl_mff_ref_cnt_mod(map, tlv_bitmap, false);
  }
  
  enum ofperr
  mf_vl_mff_nx_pull_header(struct ofpbuf *b, const struct vl_mff_map *vl_mff_map,
                           const struct mf_field **field, bool *masked,
                           uint64_t *tlv_bitmap)
  {
      enum ofperr error = nx_pull_header(b, vl_mff_map, field, masked);
      if (error) {
          return error;
      }
  
      mf_vl_mff_set_tlv_bitmap(*field, tlv_bitmap);
      return 0;
  }
  
  enum ofperr
  mf_vl_mff_nx_pull_entry(struct ofpbuf *b, const struct vl_mff_map *vl_mff_map,
                          const struct mf_field **field, union mf_value *value,
                          union mf_value *mask, uint64_t *tlv_bitmap)
  {
      enum ofperr error = nx_pull_entry(b, vl_mff_map, field, value, mask, true);
      if (error) {
          return error;
      }
  
      mf_vl_mff_set_tlv_bitmap(*field, tlv_bitmap);
      return 0;
  }
  
  enum ofperr
  mf_vl_mff_mf_from_nxm_header(uint32_t header,
                               const struct vl_mff_map *vl_mff_map,
                               const struct mf_field **field,
                               uint64_t *tlv_bitmap)
  {
      *field = mf_from_nxm_header(header, vl_mff_map);
      if (!*field) {
          return OFPERR_OFPBAC_BAD_SET_TYPE;
      } else if (mf_vl_mff_invalid(*field, vl_mff_map)) {
          return OFPERR_NXFMFC_INVALID_TLV_FIELD;
      }
  
      mf_vl_mff_set_tlv_bitmap(*field, tlv_bitmap);
      return 0;
  }
  
  /* Returns true if the 1-bits in 'super' are a superset of the 1-bits in 'sub',
   * false otherwise. */
  bool
  mf_bitmap_is_superset(const struct mf_bitmap *super,
                        const struct mf_bitmap *sub)
  {
      return bitmap_is_superset(super->bm, sub->bm, MFF_N_IDS);
  }
  
  /* Returns the bitwise-and of 'a' and 'b'. */
  struct mf_bitmap
  mf_bitmap_and(struct mf_bitmap a, struct mf_bitmap b)
  {
      bitmap_and(a.bm, b.bm, MFF_N_IDS);
      return a;
  }
  
  /* Returns the bitwise-or of 'a' and 'b'. */
  struct mf_bitmap
  mf_bitmap_or(struct mf_bitmap a, struct mf_bitmap b)
  {
      bitmap_or(a.bm, b.bm, MFF_N_IDS);
      return a;
  }
  
  /* Returns the bitwise-not of 'x'. */
  struct mf_bitmap
  mf_bitmap_not(struct mf_bitmap x)
  {
      bitmap_not(x.bm, MFF_N_IDS);
      return x;
  }
  