lib/meta-flow.c

   1 /*
   2  * Copyright (c) 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <config.h>
  18
  19 #include "openvswitch/meta-flow.h"
  20
  21 #include <errno.h>
  22 #include <limits.h>
  23 #include <netinet/icmp6.h>
  24 #include <netinet/ip6.h>
  25
  26 #include "classifier.h"
  27 #include "openvswitch/dynamic-string.h"
  28 #include "nx-match.h"
  29 #include "openvswitch/ofp-util.h"
  30 #include "ovs-thread.h"
  31 #include "packets.h"
  32 #include "random.h"
  33 #include "openvswitch/shash.h"
  34 #include "socket-util.h"
  35 #include "tun-metadata.h"
  36 #include "unaligned.h"
  37 #include "util.h"
  38 #include "openvswitch/ofp-errors.h"
  39 #include "openvswitch/vlog.h"
  40
  41 VLOG_DEFINE_THIS_MODULE(meta_flow);
  42
  43 #define FLOW_U32OFS(FIELD)                                              \
  44     offsetof(struct flow, FIELD) % 4 ? -1 : offsetof(struct flow, FIELD) / 4
  45
  46 #define MF_FIELD_SIZES(MEMBER)                  \
  47     sizeof ((union mf_value *)0)->MEMBER,       \
  48     8 * sizeof ((union mf_value *)0)->MEMBER
  49
  50 extern const struct mf_field mf_fields[MFF_N_IDS]; /* Silence a warning. */
  51
  52 const struct mf_field mf_fields[MFF_N_IDS] = {
  53 #include "meta-flow.inc"
  54 };
  55
  56 /* Maps from an mf_field's 'name' or 'extra_name' to the mf_field. */
  57 static struct shash mf_by_name;
  58
  59 /* Rate limit for parse errors.  These always indicate a bug in an OpenFlow
  60  * controller and so there's not much point in showing a lot of them. */
  61 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
  62
  63 #define MF_VALUE_EXACT_8 0xff, 0xff, 0xff, 0xff,  0xff, 0xff, 0xff, 0xff
  64 #define MF_VALUE_EXACT_16 MF_VALUE_EXACT_8, MF_VALUE_EXACT_8
  65 #define MF_VALUE_EXACT_32 MF_VALUE_EXACT_16, MF_VALUE_EXACT_16
  66 #define MF_VALUE_EXACT_64 MF_VALUE_EXACT_32, MF_VALUE_EXACT_32
  67 #define MF_VALUE_EXACT_128 MF_VALUE_EXACT_64, MF_VALUE_EXACT_64
  68 #define MF_VALUE_EXACT_INITIALIZER { .tun_metadata = { MF_VALUE_EXACT_128 } }
  69
  70 const union mf_value exact_match_mask = MF_VALUE_EXACT_INITIALIZER;
  71
  72 static void nxm_init(void);
  73
  74 /* Returns the field with the given 'name', or a null pointer if no field has
  75  * that name. */
  76 const struct mf_field *
  77 mf_from_name(const char *name)
  78 {
  79     nxm_init();
  80     return shash_find_data(&mf_by_name, name);
  81 }
  82
  83 static void
  84 nxm_do_init(void)
  85 {
  86     int i;
  87
  88     shash_init(&mf_by_name);
  89     for (i = 0; i < MFF_N_IDS; i++) {
  90         const struct mf_field *mf = &mf_fields[i];
  91
  92         ovs_assert(mf->id == i); /* Fields must be in the enum order. */
  93
  94         shash_add_once(&mf_by_name, mf->name, mf);
  95         if (mf->extra_name) {
  96             shash_add_once(&mf_by_name, mf->extra_name, mf);
  97         }
  98     }
  99 }
 100
 101 static void
 102 nxm_init(void)
 103 {
 104     static pthread_once_t once = PTHREAD_ONCE_INIT;
 105     pthread_once(&once, nxm_do_init);
 106 }
 107
 108 /* Consider the two value/mask pairs 'a_value/a_mask' and 'b_value/b_mask' as
 109  * restrictions on a field's value.  Then, this function initializes
 110  * 'dst_value/dst_mask' such that it combines the restrictions of both pairs.
 111  * This is not always possible, i.e. if one pair insists on a value of 0 in
 112  * some bit and the other pair insists on a value of 1 in that bit.  This
 113  * function returns false in a case where the combined restriction is
 114  * impossible (in which case 'dst_value/dst_mask' is not fully initialized),
 115  * true otherwise.
 116  *
 117  * (As usually true for value/mask pairs in OVS, any 1-bit in a value must have
 118  * a corresponding 1-bit in its mask.) */
 119 bool
 120 mf_subvalue_intersect(const union mf_subvalue *a_value,
 121                       const union mf_subvalue *a_mask,
 122                       const union mf_subvalue *b_value,
 123                       const union mf_subvalue *b_mask,
 124                       union mf_subvalue *dst_value,
 125                       union mf_subvalue *dst_mask)
 126 {
 127     for (int i = 0; i < ARRAY_SIZE(a_value->be64); i++) {
 128         ovs_be64 av = a_value->be64[i];
 129         ovs_be64 am = a_mask->be64[i];
 130         ovs_be64 bv = b_value->be64[i];
 131         ovs_be64 bm = b_mask->be64[i];
 132         ovs_be64 *dv = &dst_value->be64[i];
 133         ovs_be64 *dm = &dst_mask->be64[i];
 134
 135         if ((av ^ bv) & (am & bm)) {
 136             return false;
 137         }
 138         *dv = av | bv;
 139         *dm = am | bm;
 140     }
 141     return true;
 142 }
 143
 144 /* Returns the "number of bits" in 'v', e.g. 1 if only the lowest-order bit is
 145  * set, 2 if the second-lowest-order bit is set, and so on. */
 146 int
 147 mf_subvalue_width(const union mf_subvalue *v)
 148 {
 149     return 1 + bitwise_rscan(v, sizeof *v, true, sizeof *v * 8 - 1, -1);
 150 }
 151
 152 /* For positive 'n', shifts the bits in 'value' 'n' bits to the left, and for
 153  * negative 'n', shifts the bits '-n' bits to the right. */
 154 void
 155 mf_subvalue_shift(union mf_subvalue *value, int n)
 156 {
 157     if (n) {
 158         union mf_subvalue tmp;
 159         memset(&tmp, 0, sizeof tmp);
 160
 161         if (n > 0 && n < 8 * sizeof tmp) {
 162             bitwise_copy(value, sizeof *value, 0,
 163                          &tmp, sizeof tmp, n,
 164                          8 * sizeof tmp - n);
 165         } else if (n < 0 && n > -8 * sizeof tmp) {
 166             bitwise_copy(value, sizeof *value, -n,
 167                          &tmp, sizeof tmp, 0,
 168                          8 * sizeof tmp + n);
 169         }
 170         *value = tmp;
 171     }
 172 }
 173
 174 /* Appends a formatted representation of 'sv' to 's'. */
 175 void
 176 mf_subvalue_format(const union mf_subvalue *sv, struct ds *s)
 177 {
 178     ds_put_hex(s, sv, sizeof *sv);
 179 }
 180
 181 /* Returns true if 'wc' wildcards all the bits in field 'mf', false if 'wc'
 182  * specifies at least one bit in the field.
 183  *
 184  * The caller is responsible for ensuring that 'wc' corresponds to a flow that
 185  * meets 'mf''s prerequisites. */
 186 bool
 187 mf_is_all_wild(const struct mf_field *mf, const struct flow_wildcards *wc)
 188 {
 189     switch (mf->id) {
 190     case MFF_DP_HASH:
 191         return !wc->masks.dp_hash;
 192     case MFF_RECIRC_ID:
 193         return !wc->masks.recirc_id;
 194     case MFF_CONJ_ID:
 195         return !wc->masks.conj_id;
 196     case MFF_TUN_SRC:
 197         return !wc->masks.tunnel.ip_src;
 198     case MFF_TUN_DST:
 199         return !wc->masks.tunnel.ip_dst;
 200     case MFF_TUN_IPV6_SRC:
 201         return ipv6_mask_is_any(&wc->masks.tunnel.ipv6_src);
 202     case MFF_TUN_IPV6_DST:
 203         return ipv6_mask_is_any(&wc->masks.tunnel.ipv6_dst);
 204     case MFF_TUN_ID:
 205         return !wc->masks.tunnel.tun_id;
 206     case MFF_TUN_TOS:
 207         return !wc->masks.tunnel.ip_tos;
 208     case MFF_TUN_TTL:
 209         return !wc->masks.tunnel.ip_ttl;
 210     case MFF_TUN_FLAGS:
 211         return !(wc->masks.tunnel.flags & FLOW_TNL_PUB_F_MASK);
 212     case MFF_TUN_GBP_ID:
 213         return !wc->masks.tunnel.gbp_id;
 214     case MFF_TUN_GBP_FLAGS:
 215         return !wc->masks.tunnel.gbp_flags;
 216     CASE_MFF_TUN_METADATA:
 217         return !ULLONG_GET(wc->masks.tunnel.metadata.present.map,
 218                            mf->id - MFF_TUN_METADATA0);
 219     case MFF_METADATA:
 220         return !wc->masks.metadata;
 221     case MFF_IN_PORT:
 222     case MFF_IN_PORT_OXM:
 223         return !wc->masks.in_port.ofp_port;
 224     case MFF_SKB_PRIORITY:
 225         return !wc->masks.skb_priority;
 226     case MFF_PKT_MARK:
 227         return !wc->masks.pkt_mark;
 228     case MFF_CT_STATE:
 229         return !wc->masks.ct_state;
 230     case MFF_CT_ZONE:
 231         return !wc->masks.ct_zone;
 232     case MFF_CT_MARK:
 233         return !wc->masks.ct_mark;
 234     case MFF_CT_LABEL:
 235         return ovs_u128_is_zero(wc->masks.ct_label);
 236     CASE_MFF_REGS:
 237         return !wc->masks.regs[mf->id - MFF_REG0];
 238     CASE_MFF_XREGS:
 239         return !flow_get_xreg(&wc->masks, mf->id - MFF_XREG0);
 240     CASE_MFF_XXREGS: {
 241         ovs_u128 value = flow_get_xxreg(&wc->masks, mf->id - MFF_XXREG0);
 242         return ovs_u128_is_zero(value);
 243     }
 244     case MFF_ACTSET_OUTPUT:
 245         return !wc->masks.actset_output;
 246
 247     case MFF_ETH_SRC:
 248         return eth_addr_is_zero(wc->masks.dl_src);
 249     case MFF_ETH_DST:
 250         return eth_addr_is_zero(wc->masks.dl_dst);
 251     case MFF_ETH_TYPE:
 252         return !wc->masks.dl_type;
 253
 254     case MFF_ARP_SHA:
 255     case MFF_ND_SLL:
 256         return eth_addr_is_zero(wc->masks.arp_sha);
 257
 258     case MFF_ARP_THA:
 259     case MFF_ND_TLL:
 260         return eth_addr_is_zero(wc->masks.arp_tha);
 261
 262     case MFF_VLAN_TCI:
 263         return !wc->masks.vlan_tci;
 264     case MFF_DL_VLAN:
 265         return !(wc->masks.vlan_tci & htons(VLAN_VID_MASK));
 266     case MFF_VLAN_VID:
 267         return !(wc->masks.vlan_tci & htons(VLAN_VID_MASK | VLAN_CFI));
 268     case MFF_DL_VLAN_PCP:
 269     case MFF_VLAN_PCP:
 270         return !(wc->masks.vlan_tci & htons(VLAN_PCP_MASK));
 271
 272     case MFF_MPLS_LABEL:
 273         return !(wc->masks.mpls_lse[0] & htonl(MPLS_LABEL_MASK));
 274     case MFF_MPLS_TC:
 275         return !(wc->masks.mpls_lse[0] & htonl(MPLS_TC_MASK));
 276     case MFF_MPLS_BOS:
 277         return !(wc->masks.mpls_lse[0] & htonl(MPLS_BOS_MASK));
 278     case MFF_MPLS_TTL:
 279         return !(wc->masks.mpls_lse[0] & htonl(MPLS_TTL_MASK));
 280
 281     case MFF_IPV4_SRC:
 282         return !wc->masks.nw_src;
 283     case MFF_IPV4_DST:
 284         return !wc->masks.nw_dst;
 285
 286     case MFF_IPV6_SRC:
 287         return ipv6_mask_is_any(&wc->masks.ipv6_src);
 288     case MFF_IPV6_DST:
 289         return ipv6_mask_is_any(&wc->masks.ipv6_dst);
 290
 291     case MFF_IPV6_LABEL:
 292         return !wc->masks.ipv6_label;
 293
 294     case MFF_IP_PROTO:
 295         return !wc->masks.nw_proto;
 296     case MFF_IP_DSCP:
 297     case MFF_IP_DSCP_SHIFTED:
 298         return !(wc->masks.nw_tos & IP_DSCP_MASK);
 299     case MFF_IP_ECN:
 300         return !(wc->masks.nw_tos & IP_ECN_MASK);
 301     case MFF_IP_TTL:
 302         return !wc->masks.nw_ttl;
 303
 304     case MFF_ND_TARGET:
 305         return ipv6_mask_is_any(&wc->masks.nd_target);
 306
 307     case MFF_IP_FRAG:
 308         return !(wc->masks.nw_frag & FLOW_NW_FRAG_MASK);
 309
 310     case MFF_ARP_OP:
 311         return !wc->masks.nw_proto;
 312     case MFF_ARP_SPA:
 313         return !wc->masks.nw_src;
 314     case MFF_ARP_TPA:
 315         return !wc->masks.nw_dst;
 316
 317     case MFF_TCP_SRC:
 318     case MFF_UDP_SRC:
 319     case MFF_SCTP_SRC:
 320     case MFF_ICMPV4_TYPE:
 321     case MFF_ICMPV6_TYPE:
 322         return !wc->masks.tp_src;
 323     case MFF_TCP_DST:
 324     case MFF_UDP_DST:
 325     case MFF_SCTP_DST:
 326     case MFF_ICMPV4_CODE:
 327     case MFF_ICMPV6_CODE:
 328         return !wc->masks.tp_dst;
 329     case MFF_TCP_FLAGS:
 330         return !wc->masks.tcp_flags;
 331
 332     case MFF_N_IDS:
 333     default:
 334         OVS_NOT_REACHED();
 335     }
 336 }
 337
 338 /* Initializes 'mask' with the wildcard bit pattern for field 'mf' within 'wc'.
 339  * Each bit in 'mask' will be set to 1 if the bit is significant for matching
 340  * purposes, or to 0 if it is wildcarded.
 341  *
 342  * The caller is responsible for ensuring that 'wc' corresponds to a flow that
 343  * meets 'mf''s prerequisites. */
 344 void
 345 mf_get_mask(const struct mf_field *mf, const struct flow_wildcards *wc,
 346             union mf_value *mask)
 347 {
 348     mf_get_value(mf, &wc->masks, mask);
 349 }
 350
 351 /* Tests whether 'mask' is a valid wildcard bit pattern for 'mf'.  Returns true
 352  * if the mask is valid, false otherwise. */
 353 bool
 354 mf_is_mask_valid(const struct mf_field *mf, const union mf_value *mask)
 355 {
 356     switch (mf->maskable) {
 357     case MFM_NONE:
 358         return (is_all_zeros(mask, mf->n_bytes) ||
 359                 is_all_ones(mask, mf->n_bytes));
 360
 361     case MFM_FULLY:
 362         return true;
 363     }
 364
 365     OVS_NOT_REACHED();
 366 }
 367
 368 /* Returns true if 'flow' meets the prerequisites for 'mf', false otherwise.
 369  * Sets inspected bits in 'wc', if non-NULL. */
 370 bool
 371 mf_are_prereqs_ok(const struct mf_field *mf, const struct flow *flow,
 372                   struct flow_wildcards *wc)
 373 {
 374     switch (mf->prereqs) {
 375     case MFP_NONE:
 376         return true;
 377     case MFP_ARP:
 378         return (flow->dl_type == htons(ETH_TYPE_ARP) ||
 379                 flow->dl_type == htons(ETH_TYPE_RARP));
 380     case MFP_IPV4:
 381         return flow->dl_type == htons(ETH_TYPE_IP);
 382     case MFP_IPV6:
 383         return flow->dl_type == htons(ETH_TYPE_IPV6);
 384     case MFP_VLAN_VID:
 385         return is_vlan(flow, wc);
 386     case MFP_MPLS:
 387         return eth_type_mpls(flow->dl_type);
 388     case MFP_IP_ANY:
 389         return is_ip_any(flow);
 390     case MFP_TCP:
 391         return is_tcp(flow, wc) && !(flow->nw_frag & FLOW_NW_FRAG_LATER);
 392     case MFP_UDP:
 393         return is_udp(flow, wc) && !(flow->nw_frag & FLOW_NW_FRAG_LATER);
 394     case MFP_SCTP:
 395         return is_sctp(flow, wc) && !(flow->nw_frag & FLOW_NW_FRAG_LATER);
 396     case MFP_ICMPV4:
 397         return is_icmpv4(flow, wc);
 398     case MFP_ICMPV6:
 399         return is_icmpv6(flow, wc);
 400     case MFP_ND:
 401         return is_nd(flow, wc);
 402     case MFP_ND_SOLICIT:
 403         return is_nd(flow, wc) && flow->tp_src == htons(ND_NEIGHBOR_SOLICIT);
 404     case MFP_ND_ADVERT:
 405         return is_nd(flow, wc) && flow->tp_src == htons(ND_NEIGHBOR_ADVERT);
 406     }
 407
 408     OVS_NOT_REACHED();
 409 }
 410
 411 /* Returns true if 'value' may be a valid value *as part of a masked match*,
 412  * false otherwise.
 413  *
 414  * A value is not rejected just because it is not valid for the field in
 415  * question, but only if it doesn't make sense to test the bits in question at
 416  * all.  For example, the MFF_VLAN_TCI field will never have a nonzero value
 417  * without the VLAN_CFI bit being set, but we can't reject those values because
 418  * it is still legitimate to test just for those bits (see the documentation
 419  * for NXM_OF_VLAN_TCI in meta-flow.h).  On the other hand, there is never a
 420  * reason to set the low bit of MFF_IP_DSCP to 1, so we reject that. */
 421 bool
 422 mf_is_value_valid(const struct mf_field *mf, const union mf_value *value)
 423 {
 424     switch (mf->id) {
 425     case MFF_DP_HASH:
 426     case MFF_RECIRC_ID:
 427     case MFF_CONJ_ID:
 428     case MFF_TUN_ID:
 429     case MFF_TUN_SRC:
 430     case MFF_TUN_DST:
 431     case MFF_TUN_IPV6_SRC:
 432     case MFF_TUN_IPV6_DST:
 433     case MFF_TUN_TOS:
 434     case MFF_TUN_TTL:
 435     case MFF_TUN_GBP_ID:
 436     case MFF_TUN_GBP_FLAGS:
 437     CASE_MFF_TUN_METADATA:
 438     case MFF_METADATA:
 439     case MFF_IN_PORT:
 440     case MFF_SKB_PRIORITY:
 441     case MFF_PKT_MARK:
 442     case MFF_CT_ZONE:
 443     case MFF_CT_MARK:
 444     case MFF_CT_LABEL:
 445     CASE_MFF_REGS:
 446     CASE_MFF_XREGS:
 447     CASE_MFF_XXREGS:
 448     case MFF_ETH_SRC:
 449     case MFF_ETH_DST:
 450     case MFF_ETH_TYPE:
 451     case MFF_VLAN_TCI:
 452     case MFF_MPLS_TTL:
 453     case MFF_IPV4_SRC:
 454     case MFF_IPV4_DST:
 455     case MFF_IPV6_SRC:
 456     case MFF_IPV6_DST:
 457     case MFF_IP_PROTO:
 458     case MFF_IP_TTL:
 459     case MFF_ARP_SPA:
 460     case MFF_ARP_TPA:
 461     case MFF_ARP_SHA:
 462     case MFF_ARP_THA:
 463     case MFF_TCP_SRC:
 464     case MFF_TCP_DST:
 465     case MFF_UDP_SRC:
 466     case MFF_UDP_DST:
 467     case MFF_SCTP_SRC:
 468     case MFF_SCTP_DST:
 469     case MFF_ICMPV4_TYPE:
 470     case MFF_ICMPV4_CODE:
 471     case MFF_ICMPV6_TYPE:
 472     case MFF_ICMPV6_CODE:
 473     case MFF_ND_TARGET:
 474     case MFF_ND_SLL:
 475     case MFF_ND_TLL:
 476         return true;
 477
 478     case MFF_IN_PORT_OXM:
 479     case MFF_ACTSET_OUTPUT: {
 480         ofp_port_t port;
 481         return !ofputil_port_from_ofp11(value->be32, &port);
 482     }
 483
 484     case MFF_IP_DSCP:
 485         return !(value->u8 & ~IP_DSCP_MASK);
 486     case MFF_IP_DSCP_SHIFTED:
 487         return !(value->u8 & (~IP_DSCP_MASK >> 2));
 488     case MFF_IP_ECN:
 489         return !(value->u8 & ~IP_ECN_MASK);
 490     case MFF_IP_FRAG:
 491         return !(value->u8 & ~FLOW_NW_FRAG_MASK);
 492     case MFF_TCP_FLAGS:
 493         return !(value->be16 & ~htons(0x0fff));
 494
 495     case MFF_ARP_OP:
 496         return !(value->be16 & htons(0xff00));
 497
 498     case MFF_DL_VLAN:
 499         return !(value->be16 & htons(VLAN_CFI | VLAN_PCP_MASK));
 500     case MFF_VLAN_VID:
 501         return !(value->be16 & htons(VLAN_PCP_MASK));
 502
 503     case MFF_DL_VLAN_PCP:
 504     case MFF_VLAN_PCP:
 505         return !(value->u8 & ~(VLAN_PCP_MASK >> VLAN_PCP_SHIFT));
 506
 507     case MFF_IPV6_LABEL:
 508         return !(value->be32 & ~htonl(IPV6_LABEL_MASK));
 509
 510     case MFF_MPLS_LABEL:
 511         return !(value->be32 & ~htonl(MPLS_LABEL_MASK >> MPLS_LABEL_SHIFT));
 512
 513     case MFF_MPLS_TC:
 514         return !(value->u8 & ~(MPLS_TC_MASK >> MPLS_TC_SHIFT));
 515
 516     case MFF_MPLS_BOS:
 517         return !(value->u8 & ~(MPLS_BOS_MASK >> MPLS_BOS_SHIFT));
 518
 519     case MFF_TUN_FLAGS:
 520         return !(value->be16 & ~htons(FLOW_TNL_PUB_F_MASK));
 521
 522     case MFF_CT_STATE:
 523         return !(value->be32 & ~htonl(CS_SUPPORTED_MASK));
 524
 525     case MFF_N_IDS:
 526     default:
 527         OVS_NOT_REACHED();
 528     }
 529 }
 530
 531 /* Copies the value of field 'mf' from 'flow' into 'value'.  The caller is
 532  * responsible for ensuring that 'flow' meets 'mf''s prerequisites. */
 533 void
 534 mf_get_value(const struct mf_field *mf, const struct flow *flow,
 535              union mf_value *value)
 536 {
 537     switch (mf->id) {
 538     case MFF_DP_HASH:
 539         value->be32 = htonl(flow->dp_hash);
 540         break;
 541     case MFF_RECIRC_ID:
 542         value->be32 = htonl(flow->recirc_id);
 543         break;
 544     case MFF_CONJ_ID:
 545         value->be32 = htonl(flow->conj_id);
 546         break;
 547     case MFF_TUN_ID:
 548         value->be64 = flow->tunnel.tun_id;
 549         break;
 550     case MFF_TUN_SRC:
 551         value->be32 = flow->tunnel.ip_src;
 552         break;
 553     case MFF_TUN_DST:
 554         value->be32 = flow->tunnel.ip_dst;
 555         break;
 556     case MFF_TUN_IPV6_SRC:
 557         value->ipv6 = flow->tunnel.ipv6_src;
 558         break;
 559     case MFF_TUN_IPV6_DST:
 560         value->ipv6 = flow->tunnel.ipv6_dst;
 561         break;
 562     case MFF_TUN_FLAGS:
 563         value->be16 = htons(flow->tunnel.flags & FLOW_TNL_PUB_F_MASK);
 564         break;
 565     case MFF_TUN_GBP_ID:
 566         value->be16 = flow->tunnel.gbp_id;
 567         break;
 568     case MFF_TUN_GBP_FLAGS:
 569         value->u8 = flow->tunnel.gbp_flags;
 570         break;
 571     case MFF_TUN_TTL:
 572         value->u8 = flow->tunnel.ip_ttl;
 573         break;
 574     case MFF_TUN_TOS:
 575         value->u8 = flow->tunnel.ip_tos;
 576         break;
 577     CASE_MFF_TUN_METADATA:
 578         tun_metadata_read(&flow->tunnel, mf, value);
 579         break;
 580
 581     case MFF_METADATA:
 582         value->be64 = flow->metadata;
 583         break;
 584
 585     case MFF_IN_PORT:
 586         value->be16 = htons(ofp_to_u16(flow->in_port.ofp_port));
 587         break;
 588     case MFF_IN_PORT_OXM:
 589         value->be32 = ofputil_port_to_ofp11(flow->in_port.ofp_port);
 590         break;
 591     case MFF_ACTSET_OUTPUT:
 592         value->be32 = ofputil_port_to_ofp11(flow->actset_output);
 593         break;
 594
 595     case MFF_SKB_PRIORITY:
 596         value->be32 = htonl(flow->skb_priority);
 597         break;
 598
 599     case MFF_PKT_MARK:
 600         value->be32 = htonl(flow->pkt_mark);
 601         break;
 602
 603     case MFF_CT_STATE:
 604         value->be32 = htonl(flow->ct_state);
 605         break;
 606
 607     case MFF_CT_ZONE:
 608         value->be16 = htons(flow->ct_zone);
 609         break;
 610
 611     case MFF_CT_MARK:
 612         value->be32 = htonl(flow->ct_mark);
 613         break;
 614
 615     case MFF_CT_LABEL:
 616         value->be128 = hton128(flow->ct_label);
 617         break;
 618
 619     CASE_MFF_REGS:
 620         value->be32 = htonl(flow->regs[mf->id - MFF_REG0]);
 621         break;
 622
 623     CASE_MFF_XREGS:
 624         value->be64 = htonll(flow_get_xreg(flow, mf->id - MFF_XREG0));
 625         break;
 626
 627     CASE_MFF_XXREGS:
 628         value->be128 = hton128(flow_get_xxreg(flow, mf->id - MFF_XXREG0));
 629         break;
 630
 631     case MFF_ETH_SRC:
 632         value->mac = flow->dl_src;
 633         break;
 634
 635     case MFF_ETH_DST:
 636         value->mac = flow->dl_dst;
 637         break;
 638
 639     case MFF_ETH_TYPE:
 640         value->be16 = flow->dl_type;
 641         break;
 642
 643     case MFF_VLAN_TCI:
 644         value->be16 = flow->vlan_tci;
 645         break;
 646
 647     case MFF_DL_VLAN:
 648         value->be16 = flow->vlan_tci & htons(VLAN_VID_MASK);
 649         break;
 650     case MFF_VLAN_VID:
 651         value->be16 = flow->vlan_tci & htons(VLAN_VID_MASK | VLAN_CFI);
 652         break;
 653
 654     case MFF_DL_VLAN_PCP:
 655     case MFF_VLAN_PCP:
 656         value->u8 = vlan_tci_to_pcp(flow->vlan_tci);
 657         break;
 658
 659     case MFF_MPLS_LABEL:
 660         value->be32 = htonl(mpls_lse_to_label(flow->mpls_lse[0]));
 661         break;
 662
 663     case MFF_MPLS_TC:
 664         value->u8 = mpls_lse_to_tc(flow->mpls_lse[0]);
 665         break;
 666
 667     case MFF_MPLS_BOS:
 668         value->u8 = mpls_lse_to_bos(flow->mpls_lse[0]);
 669         break;
 670
 671     case MFF_MPLS_TTL:
 672         value->u8 = mpls_lse_to_ttl(flow->mpls_lse[0]);
 673         break;
 674
 675     case MFF_IPV4_SRC:
 676         value->be32 = flow->nw_src;
 677         break;
 678
 679     case MFF_IPV4_DST:
 680         value->be32 = flow->nw_dst;
 681         break;
 682
 683     case MFF_IPV6_SRC:
 684         value->ipv6 = flow->ipv6_src;
 685         break;
 686
 687     case MFF_IPV6_DST:
 688         value->ipv6 = flow->ipv6_dst;
 689         break;
 690
 691     case MFF_IPV6_LABEL:
 692         value->be32 = flow->ipv6_label;
 693         break;
 694
 695     case MFF_IP_PROTO:
 696         value->u8 = flow->nw_proto;
 697         break;
 698
 699     case MFF_IP_DSCP:
 700         value->u8 = flow->nw_tos & IP_DSCP_MASK;
 701         break;
 702
 703     case MFF_IP_DSCP_SHIFTED:
 704         value->u8 = flow->nw_tos >> 2;
 705         break;
 706
 707     case MFF_IP_ECN:
 708         value->u8 = flow->nw_tos & IP_ECN_MASK;
 709         break;
 710
 711     case MFF_IP_TTL:
 712         value->u8 = flow->nw_ttl;
 713         break;
 714
 715     case MFF_IP_FRAG:
 716         value->u8 = flow->nw_frag;
 717         break;
 718
 719     case MFF_ARP_OP:
 720         value->be16 = htons(flow->nw_proto);
 721         break;
 722
 723     case MFF_ARP_SPA:
 724         value->be32 = flow->nw_src;
 725         break;
 726
 727     case MFF_ARP_TPA:
 728         value->be32 = flow->nw_dst;
 729         break;
 730
 731     case MFF_ARP_SHA:
 732     case MFF_ND_SLL:
 733         value->mac = flow->arp_sha;
 734         break;
 735
 736     case MFF_ARP_THA:
 737     case MFF_ND_TLL:
 738         value->mac = flow->arp_tha;
 739         break;
 740
 741     case MFF_TCP_SRC:
 742     case MFF_UDP_SRC:
 743     case MFF_SCTP_SRC:
 744         value->be16 = flow->tp_src;
 745         break;
 746
 747     case MFF_TCP_DST:
 748     case MFF_UDP_DST:
 749     case MFF_SCTP_DST:
 750         value->be16 = flow->tp_dst;
 751         break;
 752
 753     case MFF_TCP_FLAGS:
 754         value->be16 = flow->tcp_flags;
 755         break;
 756
 757     case MFF_ICMPV4_TYPE:
 758     case MFF_ICMPV6_TYPE:
 759         value->u8 = ntohs(flow->tp_src);
 760         break;
 761
 762     case MFF_ICMPV4_CODE:
 763     case MFF_ICMPV6_CODE:
 764         value->u8 = ntohs(flow->tp_dst);
 765         break;
 766
 767     case MFF_ND_TARGET:
 768         value->ipv6 = flow->nd_target;
 769         break;
 770
 771     case MFF_N_IDS:
 772     default:
 773         OVS_NOT_REACHED();
 774     }
 775 }
 776
 777 /* Makes 'match' match field 'mf' exactly, with the value matched taken from
 778  * 'value'.  The caller is responsible for ensuring that 'match' meets 'mf''s
 779  * prerequisites.
 780  *
 781  * If non-NULL, 'err_str' returns a malloc'ed string describing any errors
 782  * with the request or NULL if there is no error. The caller is reponsible
 783  * for freeing the string. */
 784 void
 785 mf_set_value(const struct mf_field *mf,
 786              const union mf_value *value, struct match *match, char **err_str)
 787 {
 788     if (err_str) {
 789         *err_str = NULL;
 790     }
 791
 792     switch (mf->id) {
 793     case MFF_DP_HASH:
 794         match_set_dp_hash(match, ntohl(value->be32));
 795         break;
 796     case MFF_RECIRC_ID:
 797         match_set_recirc_id(match, ntohl(value->be32));
 798         break;
 799     case MFF_CONJ_ID:
 800         match_set_conj_id(match, ntohl(value->be32));
 801         break;
 802     case MFF_TUN_ID:
 803         match_set_tun_id(match, value->be64);
 804         break;
 805     case MFF_TUN_SRC:
 806         match_set_tun_src(match, value->be32);
 807         break;
 808     case MFF_TUN_DST:
 809         match_set_tun_dst(match, value->be32);
 810         break;
 811     case MFF_TUN_IPV6_SRC:
 812         match_set_tun_ipv6_src(match, &value->ipv6);
 813         break;
 814     case MFF_TUN_IPV6_DST:
 815         match_set_tun_ipv6_dst(match, &value->ipv6);
 816         break;
 817     case MFF_TUN_FLAGS:
 818         match_set_tun_flags(match, ntohs(value->be16));
 819         break;
 820     case MFF_TUN_GBP_ID:
 821          match_set_tun_gbp_id(match, value->be16);
 822          break;
 823     case MFF_TUN_GBP_FLAGS:
 824          match_set_tun_gbp_flags(match, value->u8);
 825          break;
 826     case MFF_TUN_TOS:
 827         match_set_tun_tos(match, value->u8);
 828         break;
 829     case MFF_TUN_TTL:
 830         match_set_tun_ttl(match, value->u8);
 831         break;
 832     CASE_MFF_TUN_METADATA:
 833         tun_metadata_set_match(mf, value, NULL, match, err_str);
 834         break;
 835
 836     case MFF_METADATA:
 837         match_set_metadata(match, value->be64);
 838         break;
 839
 840     case MFF_IN_PORT:
 841         match_set_in_port(match, u16_to_ofp(ntohs(value->be16)));
 842         break;
 843
 844     case MFF_IN_PORT_OXM: {
 845         ofp_port_t port;
 846         ofputil_port_from_ofp11(value->be32, &port);
 847         match_set_in_port(match, port);
 848         break;
 849     }
 850     case MFF_ACTSET_OUTPUT: {
 851         ofp_port_t port;
 852         ofputil_port_from_ofp11(value->be32, &port);
 853         match_set_actset_output(match, port);
 854         break;
 855     }
 856
 857     case MFF_SKB_PRIORITY:
 858         match_set_skb_priority(match, ntohl(value->be32));
 859         break;
 860
 861     case MFF_PKT_MARK:
 862         match_set_pkt_mark(match, ntohl(value->be32));
 863         break;
 864
 865     case MFF_CT_STATE:
 866         match_set_ct_state(match, ntohl(value->be32));
 867         break;
 868
 869     case MFF_CT_ZONE:
 870         match_set_ct_zone(match, ntohs(value->be16));
 871         break;
 872
 873     case MFF_CT_MARK:
 874         match_set_ct_mark(match, ntohl(value->be32));
 875         break;
 876
 877     case MFF_CT_LABEL:
 878         match_set_ct_label(match, ntoh128(value->be128));
 879         break;
 880
 881     CASE_MFF_REGS:
 882         match_set_reg(match, mf->id - MFF_REG0, ntohl(value->be32));
 883         break;
 884
 885     CASE_MFF_XREGS:
 886         match_set_xreg(match, mf->id - MFF_XREG0, ntohll(value->be64));
 887         break;
 888
 889     CASE_MFF_XXREGS:
 890         match_set_xxreg(match, mf->id - MFF_XXREG0, ntoh128(value->be128));
 891         break;
 892
 893     case MFF_ETH_SRC:
 894         match_set_dl_src(match, value->mac);
 895         break;
 896
 897     case MFF_ETH_DST:
 898         match_set_dl_dst(match, value->mac);
 899         break;
 900
 901     case MFF_ETH_TYPE:
 902         match_set_dl_type(match, value->be16);
 903         break;
 904
 905     case MFF_VLAN_TCI:
 906         match_set_dl_tci(match, value->be16);
 907         break;
 908
 909     case MFF_DL_VLAN:
 910         match_set_dl_vlan(match, value->be16);
 911         break;
 912     case MFF_VLAN_VID:
 913         match_set_vlan_vid(match, value->be16);
 914         break;
 915
 916     case MFF_DL_VLAN_PCP:
 917     case MFF_VLAN_PCP:
 918         match_set_dl_vlan_pcp(match, value->u8);
 919         break;
 920
 921     case MFF_MPLS_LABEL:
 922         match_set_mpls_label(match, 0, value->be32);
 923         break;
 924
 925     case MFF_MPLS_TC:
 926         match_set_mpls_tc(match, 0, value->u8);
 927         break;
 928
 929     case MFF_MPLS_BOS:
 930         match_set_mpls_bos(match, 0, value->u8);
 931         break;
 932
 933     case MFF_MPLS_TTL:
 934         match_set_mpls_ttl(match, 0, value->u8);
 935         break;
 936
 937     case MFF_IPV4_SRC:
 938         match_set_nw_src(match, value->be32);
 939         break;
 940
 941     case MFF_IPV4_DST:
 942         match_set_nw_dst(match, value->be32);
 943         break;
 944
 945     case MFF_IPV6_SRC:
 946         match_set_ipv6_src(match, &value->ipv6);
 947         break;
 948
 949     case MFF_IPV6_DST:
 950         match_set_ipv6_dst(match, &value->ipv6);
 951         break;
 952
 953     case MFF_IPV6_LABEL:
 954         match_set_ipv6_label(match, value->be32);
 955         break;
 956
 957     case MFF_IP_PROTO:
 958         match_set_nw_proto(match, value->u8);
 959         break;
 960
 961     case MFF_IP_DSCP:
 962         match_set_nw_dscp(match, value->u8);
 963         break;
 964
 965     case MFF_IP_DSCP_SHIFTED:
 966         match_set_nw_dscp(match, value->u8 << 2);
 967         break;
 968
 969     case MFF_IP_ECN:
 970         match_set_nw_ecn(match, value->u8);
 971         break;
 972
 973     case MFF_IP_TTL:
 974         match_set_nw_ttl(match, value->u8);
 975         break;
 976
 977     case MFF_IP_FRAG:
 978         match_set_nw_frag(match, value->u8);
 979         break;
 980
 981     case MFF_ARP_OP:
 982         match_set_nw_proto(match, ntohs(value->be16));
 983         break;
 984
 985     case MFF_ARP_SPA:
 986         match_set_nw_src(match, value->be32);
 987         break;
 988
 989     case MFF_ARP_TPA:
 990         match_set_nw_dst(match, value->be32);
 991         break;
 992
 993     case MFF_ARP_SHA:
 994     case MFF_ND_SLL:
 995         match_set_arp_sha(match, value->mac);
 996         break;
 997
 998     case MFF_ARP_THA:
 999     case MFF_ND_TLL:
1000         match_set_arp_tha(match, value->mac);
1001         break;
1002
1003     case MFF_TCP_SRC:
1004     case MFF_UDP_SRC:
1005     case MFF_SCTP_SRC:
1006         match_set_tp_src(match, value->be16);
1007         break;
1008
1009     case MFF_TCP_DST:
1010     case MFF_UDP_DST:
1011     case MFF_SCTP_DST:
1012         match_set_tp_dst(match, value->be16);
1013         break;
1014
1015     case MFF_TCP_FLAGS:
1016         match_set_tcp_flags(match, value->be16);
1017         break;
1018
1019     case MFF_ICMPV4_TYPE:
1020     case MFF_ICMPV6_TYPE:
1021         match_set_icmp_type(match, value->u8);
1022         break;
1023
1024     case MFF_ICMPV4_CODE:
1025     case MFF_ICMPV6_CODE:
1026         match_set_icmp_code(match, value->u8);
1027         break;
1028
1029     case MFF_ND_TARGET:
1030         match_set_nd_target(match, &value->ipv6);
1031         break;
1032
1033     case MFF_N_IDS:
1034     default:
1035         OVS_NOT_REACHED();
1036     }
1037 }
1038
1039 /* Unwildcard the bits in 'mask' of the 'wc' member field described by 'mf'.
1040  * The caller is responsible for ensuring that 'wc' meets 'mf''s
1041  * prerequisites. */
1042 void
1043 mf_mask_field_masked(const struct mf_field *mf, const union mf_value *mask,
1044                      struct flow_wildcards *wc)
1045 {
1046     union mf_value temp_mask;
1047     /* For MFF_DL_VLAN, we cannot send a all 1's to flow_set_dl_vlan() as that
1048      * will be considered as OFP10_VLAN_NONE. So make sure the mask only has
1049      * valid bits in this case. */
1050     if (mf->id == MFF_DL_VLAN) {
1051         temp_mask.be16 = htons(VLAN_VID_MASK) & mask->be16;
1052         mask = &temp_mask;
1053     }
1054
1055     union mf_value mask_value;
1056
1057     mf_get_value(mf, &wc->masks, &mask_value);
1058     for (size_t i = 0; i < mf->n_bytes; i++) {
1059         mask_value.b[i] |= mask->b[i];
1060     }
1061     mf_set_flow_value(mf, &mask_value, &wc->masks);
1062 }
1063
1064 /* Unwildcard 'wc' member field described by 'mf'.  The caller is
1065  * responsible for ensuring that 'mask' meets 'mf''s prerequisites. */
1066 void
1067 mf_mask_field(const struct mf_field *mf, struct flow_wildcards *wc)
1068 {
1069     mf_mask_field_masked(mf, &exact_match_mask, wc);
1070 }
1071
1072 static int
1073 field_len(const struct mf_field *mf, const union mf_value *value_)
1074 {
1075     const uint8_t *value = &value_->u8;
1076     int i;
1077
1078     if (!mf->variable_len) {
1079         return mf->n_bytes;
1080     }
1081
1082     if (!value) {
1083         return 0;
1084     }
1085
1086     for (i = 0; i < mf->n_bytes; i++) {
1087         if (value[i] != 0) {
1088             break;
1089         }
1090     }
1091
1092     return mf->n_bytes - i;
1093 }
1094
1095 /* Returns the effective length of the field. For fixed length fields,
1096  * this is just the defined length. For variable length fields, it is
1097  * the minimum size encoding that retains the same meaning (i.e.
1098  * discarding leading zeros).
1099  *
1100  * 'is_masked' returns (if non-NULL) whether the original contained
1101  * a mask. Otherwise, a mask that is the same length as the value
1102  * might be misinterpreted as an exact match. */
1103 int
1104 mf_field_len(const struct mf_field *mf, const union mf_value *value,
1105              const union mf_value *mask, bool *is_masked_)
1106 {
1107     int len, mask_len;
1108     bool is_masked = mask && !is_all_ones(mask, mf->n_bytes);
1109
1110     len = field_len(mf, value);
1111     if (is_masked) {
1112         mask_len = field_len(mf, mask);
1113         len = MAX(len, mask_len);
1114     }
1115
1116     if (is_masked_) {
1117         *is_masked_ = is_masked;
1118     }
1119
1120     return len;
1121 }
1122
1123 /* Sets 'flow' member field described by 'mf' to 'value'.  The caller is
1124  * responsible for ensuring that 'flow' meets 'mf''s prerequisites.*/
1125 void
1126 mf_set_flow_value(const struct mf_field *mf,
1127                   const union mf_value *value, struct flow *flow)
1128 {
1129     switch (mf->id) {
1130     case MFF_DP_HASH:
1131         flow->dp_hash = ntohl(value->be32);
1132         break;
1133     case MFF_RECIRC_ID:
1134         flow->recirc_id = ntohl(value->be32);
1135         break;
1136     case MFF_CONJ_ID:
1137         flow->conj_id = ntohl(value->be32);
1138         break;
1139     case MFF_TUN_ID:
1140         flow->tunnel.tun_id = value->be64;
1141         break;
1142     case MFF_TUN_SRC:
1143         flow->tunnel.ip_src = value->be32;
1144         break;
1145     case MFF_TUN_DST:
1146         flow->tunnel.ip_dst = value->be32;
1147         break;
1148     case MFF_TUN_IPV6_SRC:
1149         flow->tunnel.ipv6_src = value->ipv6;
1150         break;
1151     case MFF_TUN_IPV6_DST:
1152         flow->tunnel.ipv6_dst = value->ipv6;
1153         break;
1154     case MFF_TUN_FLAGS:
1155         flow->tunnel.flags = (flow->tunnel.flags & ~FLOW_TNL_PUB_F_MASK) |
1156                              ntohs(value->be16);
1157         break;
1158     case MFF_TUN_GBP_ID:
1159         flow->tunnel.gbp_id = value->be16;
1160         break;
1161     case MFF_TUN_GBP_FLAGS:
1162         flow->tunnel.gbp_flags = value->u8;
1163         break;
1164     case MFF_TUN_TOS:
1165         flow->tunnel.ip_tos = value->u8;
1166         break;
1167     case MFF_TUN_TTL:
1168         flow->tunnel.ip_ttl = value->u8;
1169         break;
1170     CASE_MFF_TUN_METADATA:
1171         tun_metadata_write(&flow->tunnel, mf, value);
1172         break;
1173     case MFF_METADATA:
1174         flow->metadata = value->be64;
1175         break;
1176
1177     case MFF_IN_PORT:
1178         flow->in_port.ofp_port = u16_to_ofp(ntohs(value->be16));
1179         break;
1180
1181     case MFF_IN_PORT_OXM:
1182         ofputil_port_from_ofp11(value->be32, &flow->in_port.ofp_port);
1183         break;
1184     case MFF_ACTSET_OUTPUT:
1185         ofputil_port_from_ofp11(value->be32, &flow->actset_output);
1186         break;
1187
1188     case MFF_SKB_PRIORITY:
1189         flow->skb_priority = ntohl(value->be32);
1190         break;
1191
1192     case MFF_PKT_MARK:
1193         flow->pkt_mark = ntohl(value->be32);
1194         break;
1195
1196     case MFF_CT_STATE:
1197         flow->ct_state = ntohl(value->be32);
1198         break;
1199
1200     case MFF_CT_ZONE:
1201         flow->ct_zone = ntohs(value->be16);
1202         break;
1203
1204     case MFF_CT_MARK:
1205         flow->ct_mark = ntohl(value->be32);
1206         break;
1207
1208     case MFF_CT_LABEL:
1209         flow->ct_label = ntoh128(value->be128);
1210         break;
1211
1212     CASE_MFF_REGS:
1213         flow->regs[mf->id - MFF_REG0] = ntohl(value->be32);
1214         break;
1215
1216     CASE_MFF_XREGS:
1217         flow_set_xreg(flow, mf->id - MFF_XREG0, ntohll(value->be64));
1218         break;
1219
1220     CASE_MFF_XXREGS:
1221         flow_set_xxreg(flow, mf->id - MFF_XXREG0, ntoh128(value->be128));
1222         break;
1223
1224     case MFF_ETH_SRC:
1225         flow->dl_src = value->mac;
1226         break;
1227
1228     case MFF_ETH_DST:
1229         flow->dl_dst = value->mac;
1230         break;
1231
1232     case MFF_ETH_TYPE:
1233         flow->dl_type = value->be16;
1234         break;
1235
1236     case MFF_VLAN_TCI:
1237         flow->vlan_tci = value->be16;
1238         break;
1239
1240     case MFF_DL_VLAN:
1241         flow_set_dl_vlan(flow, value->be16);
1242         break;
1243     case MFF_VLAN_VID:
1244         flow_set_vlan_vid(flow, value->be16);
1245         break;
1246
1247     case MFF_DL_VLAN_PCP:
1248     case MFF_VLAN_PCP:
1249         flow_set_vlan_pcp(flow, value->u8);
1250         break;
1251
1252     case MFF_MPLS_LABEL:
1253         flow_set_mpls_label(flow, 0, value->be32);
1254         break;
1255
1256     case MFF_MPLS_TC:
1257         flow_set_mpls_tc(flow, 0, value->u8);
1258         break;
1259
1260     case MFF_MPLS_BOS:
1261         flow_set_mpls_bos(flow, 0, value->u8);
1262         break;
1263
1264     case MFF_MPLS_TTL:
1265         flow_set_mpls_ttl(flow, 0, value->u8);
1266         break;
1267
1268     case MFF_IPV4_SRC:
1269         flow->nw_src = value->be32;
1270         break;
1271
1272     case MFF_IPV4_DST:
1273         flow->nw_dst = value->be32;
1274         break;
1275
1276     case MFF_IPV6_SRC:
1277         flow->ipv6_src = value->ipv6;
1278         break;
1279
1280     case MFF_IPV6_DST:
1281         flow->ipv6_dst = value->ipv6;
1282         break;
1283
1284     case MFF_IPV6_LABEL:
1285         flow->ipv6_label = value->be32 & htonl(IPV6_LABEL_MASK);
1286         break;
1287
1288     case MFF_IP_PROTO:
1289         flow->nw_proto = value->u8;
1290         break;
1291
1292     case MFF_IP_DSCP:
1293         flow->nw_tos &= ~IP_DSCP_MASK;
1294         flow->nw_tos |= value->u8 & IP_DSCP_MASK;
1295         break;
1296
1297     case MFF_IP_DSCP_SHIFTED:
1298         flow->nw_tos &= ~IP_DSCP_MASK;
1299         flow->nw_tos |= value->u8 << 2;
1300         break;
1301
1302     case MFF_IP_ECN:
1303         flow->nw_tos &= ~IP_ECN_MASK;
1304         flow->nw_tos |= value->u8 & IP_ECN_MASK;
1305         break;
1306
1307     case MFF_IP_TTL:
1308         flow->nw_ttl = value->u8;
1309         break;
1310
1311     case MFF_IP_FRAG:
1312         flow->nw_frag = value->u8 & FLOW_NW_FRAG_MASK;
1313         break;
1314
1315     case MFF_ARP_OP:
1316         flow->nw_proto = ntohs(value->be16);
1317         break;
1318
1319     case MFF_ARP_SPA:
1320         flow->nw_src = value->be32;
1321         break;
1322
1323     case MFF_ARP_TPA:
1324         flow->nw_dst = value->be32;
1325         break;
1326
1327     case MFF_ARP_SHA:
1328     case MFF_ND_SLL:
1329         flow->arp_sha = value->mac;
1330         break;
1331
1332     case MFF_ARP_THA:
1333     case MFF_ND_TLL:
1334         flow->arp_tha = value->mac;
1335         break;
1336
1337     case MFF_TCP_SRC:
1338     case MFF_UDP_SRC:
1339     case MFF_SCTP_SRC:
1340         flow->tp_src = value->be16;
1341         break;
1342
1343     case MFF_TCP_DST:
1344     case MFF_UDP_DST:
1345     case MFF_SCTP_DST:
1346         flow->tp_dst = value->be16;
1347         break;
1348
1349     case MFF_TCP_FLAGS:
1350         flow->tcp_flags = value->be16;
1351         break;
1352
1353     case MFF_ICMPV4_TYPE:
1354     case MFF_ICMPV6_TYPE:
1355         flow->tp_src = htons(value->u8);
1356         break;
1357
1358     case MFF_ICMPV4_CODE:
1359     case MFF_ICMPV6_CODE:
1360         flow->tp_dst = htons(value->u8);
1361         break;
1362
1363     case MFF_ND_TARGET:
1364         flow->nd_target = value->ipv6;
1365         break;
1366
1367     case MFF_N_IDS:
1368     default:
1369         OVS_NOT_REACHED();
1370     }
1371 }
1372
1373 /* Consider each of 'src', 'mask', and 'dst' as if they were arrays of 8*n
1374  * bits.  Then, for each 0 <= i < 8 * n such that mask[i] == 1, sets dst[i] =
1375  * src[i].  */
1376 static void
1377 apply_mask(const uint8_t *src, const uint8_t *mask, uint8_t *dst, size_t n)
1378 {
1379     size_t i;
1380
1381     for (i = 0; i < n; i++) {
1382         dst[i] = (src[i] & mask[i]) | (dst[i] & ~mask[i]);
1383     }
1384 }
1385
1386 /* Sets 'flow' member field described by 'field' to 'value', except that bits
1387  * for which 'mask' has a 0-bit keep their existing values.  The caller is
1388  * responsible for ensuring that 'flow' meets 'field''s prerequisites.*/
1389 void
1390 mf_set_flow_value_masked(const struct mf_field *field,
1391                          const union mf_value *value,
1392                          const union mf_value *mask,
1393                          struct flow *flow)
1394 {
1395     union mf_value tmp;
1396
1397     mf_get_value(field, flow, &tmp);
1398     apply_mask((const uint8_t *) value, (const uint8_t *) mask,
1399                (uint8_t *) &tmp, field->n_bytes);
1400     mf_set_flow_value(field, &tmp, flow);
1401 }
1402
1403 bool
1404 mf_is_tun_metadata(const struct mf_field *mf)
1405 {
1406     return mf->id >= MFF_TUN_METADATA0 &&
1407            mf->id < MFF_TUN_METADATA0 + TUN_METADATA_NUM_OPTS;
1408 }
1409
1410 /* Returns true if 'mf' has previously been set in 'flow', false if
1411  * it contains a non-default value.
1412  *
1413  * The caller is responsible for ensuring that 'flow' meets 'mf''s
1414  * prerequisites. */
1415 bool
1416 mf_is_set(const struct mf_field *mf, const struct flow *flow)
1417 {
1418     if (!mf_is_tun_metadata(mf)) {
1419         union mf_value value;
1420
1421         mf_get_value(mf, flow, &value);
1422         return !is_all_zeros(&value, mf->n_bytes);
1423     } else {
1424         return ULLONG_GET(flow->tunnel.metadata.present.map,
1425                           mf->id - MFF_TUN_METADATA0);
1426     }
1427 }
1428
1429 /* Makes 'match' wildcard field 'mf'.
1430  *
1431  * The caller is responsible for ensuring that 'match' meets 'mf''s
1432  * prerequisites.
1433  *
1434  * If non-NULL, 'err_str' returns a malloc'ed string describing any errors
1435  * with the request or NULL if there is no error. The caller is reponsible
1436  * for freeing the string. */
1437 void
1438 mf_set_wild(const struct mf_field *mf, struct match *match, char **err_str)
1439 {
1440     if (err_str) {
1441         *err_str = NULL;
1442     }
1443
1444     switch (mf->id) {
1445     case MFF_DP_HASH:
1446         match->flow.dp_hash = 0;
1447         match->wc.masks.dp_hash = 0;
1448         break;
1449     case MFF_RECIRC_ID:
1450         match->flow.recirc_id = 0;
1451         match->wc.masks.recirc_id = 0;
1452         break;
1453     case MFF_CONJ_ID:
1454         match->flow.conj_id = 0;
1455         match->wc.masks.conj_id = 0;
1456         break;
1457     case MFF_TUN_ID:
1458         match_set_tun_id_masked(match, htonll(0), htonll(0));
1459         break;
1460     case MFF_TUN_SRC:
1461         match_set_tun_src_masked(match, htonl(0), htonl(0));
1462         break;
1463     case MFF_TUN_DST:
1464         match_set_tun_dst_masked(match, htonl(0), htonl(0));
1465         break;
1466     case MFF_TUN_IPV6_SRC:
1467         memset(&match->wc.masks.tunnel.ipv6_src, 0,
1468                sizeof match->wc.masks.tunnel.ipv6_src);
1469         memset(&match->flow.tunnel.ipv6_src, 0,
1470                sizeof match->flow.tunnel.ipv6_src);
1471         break;
1472     case MFF_TUN_IPV6_DST:
1473         memset(&match->wc.masks.tunnel.ipv6_dst, 0,
1474                sizeof match->wc.masks.tunnel.ipv6_dst);
1475         memset(&match->flow.tunnel.ipv6_dst, 0,
1476                sizeof match->flow.tunnel.ipv6_dst);
1477         break;
1478     case MFF_TUN_FLAGS:
1479         match_set_tun_flags_masked(match, 0, 0);
1480         break;
1481     case MFF_TUN_GBP_ID:
1482         match_set_tun_gbp_id_masked(match, 0, 0);
1483         break;
1484     case MFF_TUN_GBP_FLAGS:
1485         match_set_tun_gbp_flags_masked(match, 0, 0);
1486         break;
1487     case MFF_TUN_TOS:
1488         match_set_tun_tos_masked(match, 0, 0);
1489         break;
1490     case MFF_TUN_TTL:
1491         match_set_tun_ttl_masked(match, 0, 0);
1492         break;
1493     CASE_MFF_TUN_METADATA:
1494         tun_metadata_set_match(mf, NULL, NULL, match, err_str);
1495         break;
1496
1497     case MFF_METADATA:
1498         match_set_metadata_masked(match, htonll(0), htonll(0));
1499         break;
1500
1501     case MFF_IN_PORT:
1502     case MFF_IN_PORT_OXM:
1503         match->flow.in_port.ofp_port = 0;
1504         match->wc.masks.in_port.ofp_port = 0;
1505         break;
1506     case MFF_ACTSET_OUTPUT:
1507         match->flow.actset_output = 0;
1508         match->wc.masks.actset_output = 0;
1509         break;
1510
1511     case MFF_SKB_PRIORITY:
1512         match->flow.skb_priority = 0;
1513         match->wc.masks.skb_priority = 0;
1514         break;
1515
1516     case MFF_PKT_MARK:
1517         match->flow.pkt_mark = 0;
1518         match->wc.masks.pkt_mark = 0;
1519         break;
1520
1521     case MFF_CT_STATE:
1522         match->flow.ct_state = 0;
1523         match->wc.masks.ct_state = 0;
1524         break;
1525
1526     case MFF_CT_ZONE:
1527         match->flow.ct_zone = 0;
1528         match->wc.masks.ct_zone = 0;
1529         break;
1530
1531     case MFF_CT_MARK:
1532         match->flow.ct_mark = 0;
1533         match->wc.masks.ct_mark = 0;
1534         break;
1535
1536     case MFF_CT_LABEL:
1537         memset(&match->flow.ct_label, 0, sizeof(match->flow.ct_label));
1538         memset(&match->wc.masks.ct_label, 0, sizeof(match->wc.masks.ct_label));
1539         break;
1540
1541     CASE_MFF_REGS:
1542         match_set_reg_masked(match, mf->id - MFF_REG0, 0, 0);
1543         break;
1544
1545     CASE_MFF_XREGS:
1546         match_set_xreg_masked(match, mf->id - MFF_XREG0, 0, 0);
1547         break;
1548
1549     CASE_MFF_XXREGS: {
1550         match_set_xxreg_masked(match, mf->id - MFF_XXREG0, OVS_U128_ZERO,
1551                                OVS_U128_ZERO);
1552         break;
1553     }
1554
1555     case MFF_ETH_SRC:
1556         match->flow.dl_src = eth_addr_zero;
1557         match->wc.masks.dl_src = eth_addr_zero;
1558         break;
1559
1560     case MFF_ETH_DST:
1561         match->flow.dl_dst = eth_addr_zero;
1562         match->wc.masks.dl_dst = eth_addr_zero;
1563         break;
1564
1565     case MFF_ETH_TYPE:
1566         match->flow.dl_type = htons(0);
1567         match->wc.masks.dl_type = htons(0);
1568         break;
1569
1570     case MFF_VLAN_TCI:
1571         match_set_dl_tci_masked(match, htons(0), htons(0));
1572         break;
1573
1574     case MFF_DL_VLAN:
1575     case MFF_VLAN_VID:
1576         match_set_any_vid(match);
1577         break;
1578
1579     case MFF_DL_VLAN_PCP:
1580     case MFF_VLAN_PCP:
1581         match_set_any_pcp(match);
1582         break;
1583
1584     case MFF_MPLS_LABEL:
1585         match_set_any_mpls_label(match, 0);
1586         break;
1587
1588     case MFF_MPLS_TC:
1589         match_set_any_mpls_tc(match, 0);
1590         break;
1591
1592     case MFF_MPLS_BOS:
1593         match_set_any_mpls_bos(match, 0);
1594         break;
1595
1596     case MFF_MPLS_TTL:
1597         match_set_any_mpls_ttl(match, 0);
1598         break;
1599
1600     case MFF_IPV4_SRC:
1601     case MFF_ARP_SPA:
1602         match_set_nw_src_masked(match, htonl(0), htonl(0));
1603         break;
1604
1605     case MFF_IPV4_DST:
1606     case MFF_ARP_TPA:
1607         match_set_nw_dst_masked(match, htonl(0), htonl(0));
1608         break;
1609
1610     case MFF_IPV6_SRC:
1611         memset(&match->wc.masks.ipv6_src, 0, sizeof match->wc.masks.ipv6_src);
1612         memset(&match->flow.ipv6_src, 0, sizeof match->flow.ipv6_src);
1613         break;
1614
1615     case MFF_IPV6_DST:
1616         memset(&match->wc.masks.ipv6_dst, 0, sizeof match->wc.masks.ipv6_dst);
1617         memset(&match->flow.ipv6_dst, 0, sizeof match->flow.ipv6_dst);
1618         break;
1619
1620     case MFF_IPV6_LABEL:
1621         match->wc.masks.ipv6_label = htonl(0);
1622         match->flow.ipv6_label = htonl(0);
1623         break;
1624
1625     case MFF_IP_PROTO:
1626         match->wc.masks.nw_proto = 0;
1627         match->flow.nw_proto = 0;
1628         break;
1629
1630     case MFF_IP_DSCP:
1631     case MFF_IP_DSCP_SHIFTED:
1632         match->wc.masks.nw_tos &= ~IP_DSCP_MASK;
1633         match->flow.nw_tos &= ~IP_DSCP_MASK;
1634         break;
1635
1636     case MFF_IP_ECN:
1637         match->wc.masks.nw_tos &= ~IP_ECN_MASK;
1638         match->flow.nw_tos &= ~IP_ECN_MASK;
1639         break;
1640
1641     case MFF_IP_TTL:
1642         match->wc.masks.nw_ttl = 0;
1643         match->flow.nw_ttl = 0;
1644         break;
1645
1646     case MFF_IP_FRAG:
1647         match->wc.masks.nw_frag &= ~FLOW_NW_FRAG_MASK;
1648         match->flow.nw_frag &= ~FLOW_NW_FRAG_MASK;
1649         break;
1650
1651     case MFF_ARP_OP:
1652         match->wc.masks.nw_proto = 0;
1653         match->flow.nw_proto = 0;
1654         break;
1655
1656     case MFF_ARP_SHA:
1657     case MFF_ND_SLL:
1658         match->flow.arp_sha = eth_addr_zero;
1659         match->wc.masks.arp_sha = eth_addr_zero;
1660         break;
1661
1662     case MFF_ARP_THA:
1663     case MFF_ND_TLL:
1664         match->flow.arp_tha = eth_addr_zero;
1665         match->wc.masks.arp_tha = eth_addr_zero;
1666         break;
1667
1668     case MFF_TCP_SRC:
1669     case MFF_UDP_SRC:
1670     case MFF_SCTP_SRC:
1671     case MFF_ICMPV4_TYPE:
1672     case MFF_ICMPV6_TYPE:
1673         match->wc.masks.tp_src = htons(0);
1674         match->flow.tp_src = htons(0);
1675         break;
1676
1677     case MFF_TCP_DST:
1678     case MFF_UDP_DST:
1679     case MFF_SCTP_DST:
1680     case MFF_ICMPV4_CODE:
1681     case MFF_ICMPV6_CODE:
1682         match->wc.masks.tp_dst = htons(0);
1683         match->flow.tp_dst = htons(0);
1684         break;
1685
1686     case MFF_TCP_FLAGS:
1687         match->wc.masks.tcp_flags = htons(0);
1688         match->flow.tcp_flags = htons(0);
1689         break;
1690
1691     case MFF_ND_TARGET:
1692         memset(&match->wc.masks.nd_target, 0,
1693                sizeof match->wc.masks.nd_target);
1694         memset(&match->flow.nd_target, 0, sizeof match->flow.nd_target);
1695         break;
1696
1697     case MFF_N_IDS:
1698     default:
1699         OVS_NOT_REACHED();
1700     }
1701 }
1702
1703 /* Makes 'match' match field 'mf' with the specified 'value' and 'mask'.
1704  * 'value' specifies a value to match and 'mask' specifies a wildcard pattern,
1705  * with a 1-bit indicating that the corresponding value bit must match and a
1706  * 0-bit indicating a don't-care.
1707  *
1708  * If 'mask' is NULL or points to all-1-bits, then this call is equivalent to
1709  * mf_set_value(mf, value, match).  If 'mask' points to all-0-bits, then this
1710  * call is equivalent to mf_set_wild(mf, match).
1711  *
1712  * 'mask' must be a valid mask for 'mf' (see mf_is_mask_valid()).  The caller
1713  * is responsible for ensuring that 'match' meets 'mf''s prerequisites.
1714  *
1715  * If non-NULL, 'err_str' returns a malloc'ed string describing any errors
1716  * with the request or NULL if there is no error. The caller is reponsible
1717  * for freeing the string.
1718  *
1719  * Return a set of enum ofputil_protocol bits (as an uint32_t to avoid circular
1720  * dependency on enum ofputil_protocol definition) indicating which OpenFlow
1721  * protocol versions can support this functionality. */
1722 uint32_t
1723 mf_set(const struct mf_field *mf,
1724        const union mf_value *value, const union mf_value *mask,
1725        struct match *match, char **err_str)
1726 {
1727     if (!mask || is_all_ones(mask, mf->n_bytes)) {
1728         mf_set_value(mf, value, match, err_str);
1729         return mf->usable_protocols_exact;
1730     } else if (is_all_zeros(mask, mf->n_bytes) && !mf_is_tun_metadata(mf)) {
1731         /* Tunnel metadata matches on the existence of the field itself, so
1732          * it still needs to be encoded even if the value is wildcarded. */
1733         mf_set_wild(mf, match, err_str);
1734         return OFPUTIL_P_ANY;
1735     }
1736
1737     if (err_str) {
1738         *err_str = NULL;
1739     }
1740
1741     switch (mf->id) {
1742     case MFF_CT_ZONE:
1743     case MFF_RECIRC_ID:
1744     case MFF_CONJ_ID:
1745     case MFF_IN_PORT:
1746     case MFF_IN_PORT_OXM:
1747     case MFF_ACTSET_OUTPUT:
1748     case MFF_SKB_PRIORITY:
1749     case MFF_ETH_TYPE:
1750     case MFF_DL_VLAN:
1751     case MFF_DL_VLAN_PCP:
1752     case MFF_VLAN_PCP:
1753     case MFF_MPLS_LABEL:
1754     case MFF_MPLS_TC:
1755     case MFF_MPLS_BOS:
1756     case MFF_MPLS_TTL:
1757     case MFF_IP_PROTO:
1758     case MFF_IP_TTL:
1759     case MFF_IP_DSCP:
1760     case MFF_IP_DSCP_SHIFTED:
1761     case MFF_IP_ECN:
1762     case MFF_ARP_OP:
1763     case MFF_ICMPV4_TYPE:
1764     case MFF_ICMPV4_CODE:
1765     case MFF_ICMPV6_TYPE:
1766     case MFF_ICMPV6_CODE:
1767         return OFPUTIL_P_NONE;
1768
1769     case MFF_DP_HASH:
1770         match_set_dp_hash_masked(match, ntohl(value->be32), ntohl(mask->be32));
1771         break;
1772     case MFF_TUN_ID:
1773         match_set_tun_id_masked(match, value->be64, mask->be64);
1774         break;
1775     case MFF_TUN_SRC:
1776         match_set_tun_src_masked(match, value->be32, mask->be32);
1777         break;
1778     case MFF_TUN_DST:
1779         match_set_tun_dst_masked(match, value->be32, mask->be32);
1780         break;
1781     case MFF_TUN_IPV6_SRC:
1782         match_set_tun_ipv6_src_masked(match, &value->ipv6, &mask->ipv6);
1783         break;
1784     case MFF_TUN_IPV6_DST:
1785         match_set_tun_ipv6_dst_masked(match, &value->ipv6, &mask->ipv6);
1786         break;
1787     case MFF_TUN_FLAGS:
1788         match_set_tun_flags_masked(match, ntohs(value->be16), ntohs(mask->be16));
1789         break;
1790     case MFF_TUN_GBP_ID:
1791         match_set_tun_gbp_id_masked(match, value->be16, mask->be16);
1792         break;
1793     case MFF_TUN_GBP_FLAGS:
1794         match_set_tun_gbp_flags_masked(match, value->u8, mask->u8);
1795         break;
1796     case MFF_TUN_TTL:
1797         match_set_tun_ttl_masked(match, value->u8, mask->u8);
1798         break;
1799     case MFF_TUN_TOS:
1800         match_set_tun_tos_masked(match, value->u8, mask->u8);
1801         break;
1802     CASE_MFF_TUN_METADATA:
1803         tun_metadata_set_match(mf, value, mask, match, err_str);
1804         break;
1805
1806     case MFF_METADATA:
1807         match_set_metadata_masked(match, value->be64, mask->be64);
1808         break;
1809
1810     CASE_MFF_REGS:
1811         match_set_reg_masked(match, mf->id - MFF_REG0,
1812                              ntohl(value->be32), ntohl(mask->be32));
1813         break;
1814
1815     CASE_MFF_XREGS:
1816         match_set_xreg_masked(match, mf->id - MFF_XREG0,
1817                               ntohll(value->be64), ntohll(mask->be64));
1818         break;
1819
1820     CASE_MFF_XXREGS: {
1821         match_set_xxreg_masked(match, mf->id - MFF_XXREG0,
1822                 ntoh128(value->be128), ntoh128(mask->be128));
1823         break;
1824     }
1825
1826     case MFF_PKT_MARK:
1827         match_set_pkt_mark_masked(match, ntohl(value->be32),
1828                                   ntohl(mask->be32));
1829         break;
1830
1831     case MFF_CT_STATE:
1832         match_set_ct_state_masked(match, ntohl(value->be32), ntohl(mask->be32));
1833         break;
1834
1835     case MFF_CT_MARK:
1836         match_set_ct_mark_masked(match, ntohl(value->be32), ntohl(mask->be32));
1837         break;
1838
1839     case MFF_CT_LABEL:
1840         match_set_ct_label_masked(match, ntoh128(value->be128),
1841                                   mask ? ntoh128(mask->be128) : OVS_U128_MAX);
1842         break;
1843
1844     case MFF_ETH_DST:
1845         match_set_dl_dst_masked(match, value->mac, mask->mac);
1846         break;
1847
1848     case MFF_ETH_SRC:
1849         match_set_dl_src_masked(match, value->mac, mask->mac);
1850         break;
1851
1852     case MFF_ARP_SHA:
1853     case MFF_ND_SLL:
1854         match_set_arp_sha_masked(match, value->mac, mask->mac);
1855         break;
1856
1857     case MFF_ARP_THA:
1858     case MFF_ND_TLL:
1859         match_set_arp_tha_masked(match, value->mac, mask->mac);
1860         break;
1861
1862     case MFF_VLAN_TCI:
1863         match_set_dl_tci_masked(match, value->be16, mask->be16);
1864         break;
1865
1866     case MFF_VLAN_VID:
1867         match_set_vlan_vid_masked(match, value->be16, mask->be16);
1868         break;
1869
1870     case MFF_IPV4_SRC:
1871         match_set_nw_src_masked(match, value->be32, mask->be32);
1872         break;
1873
1874     case MFF_IPV4_DST:
1875         match_set_nw_dst_masked(match, value->be32, mask->be32);
1876         break;
1877
1878     case MFF_IPV6_SRC:
1879         match_set_ipv6_src_masked(match, &value->ipv6, &mask->ipv6);
1880         break;
1881
1882     case MFF_IPV6_DST:
1883         match_set_ipv6_dst_masked(match, &value->ipv6, &mask->ipv6);
1884         break;
1885
1886     case MFF_IPV6_LABEL:
1887         if ((mask->be32 & htonl(IPV6_LABEL_MASK)) == htonl(IPV6_LABEL_MASK)) {
1888             mf_set_value(mf, value, match, err_str);
1889         } else {
1890             match_set_ipv6_label_masked(match, value->be32, mask->be32);
1891         }
1892         break;
1893
1894     case MFF_ND_TARGET:
1895         match_set_nd_target_masked(match, &value->ipv6, &mask->ipv6);
1896         break;
1897
1898     case MFF_IP_FRAG:
1899         match_set_nw_frag_masked(match, value->u8, mask->u8);
1900         break;
1901
1902     case MFF_ARP_SPA:
1903         match_set_nw_src_masked(match, value->be32, mask->be32);
1904         break;
1905
1906     case MFF_ARP_TPA:
1907         match_set_nw_dst_masked(match, value->be32, mask->be32);
1908         break;
1909
1910     case MFF_TCP_SRC:
1911     case MFF_UDP_SRC:
1912     case MFF_SCTP_SRC:
1913         match_set_tp_src_masked(match, value->be16, mask->be16);
1914         break;
1915
1916     case MFF_TCP_DST:
1917     case MFF_UDP_DST:
1918     case MFF_SCTP_DST:
1919         match_set_tp_dst_masked(match, value->be16, mask->be16);
1920         break;
1921
1922     case MFF_TCP_FLAGS:
1923         match_set_tcp_flags_masked(match, value->be16, mask->be16);
1924         break;
1925
1926     case MFF_N_IDS:
1927     default:
1928         OVS_NOT_REACHED();
1929     }
1930
1931     return ((mf->usable_protocols_bitwise == mf->usable_protocols_cidr
1932              || ip_is_cidr(mask->be32))
1933             ? mf->usable_protocols_cidr
1934             : mf->usable_protocols_bitwise);
1935 }
1936
1937 static enum ofperr
1938 mf_check__(const struct mf_subfield *sf, const struct flow *flow,
1939            const char *type)
1940 {
1941     if (!sf->field) {
1942         VLOG_WARN_RL(&rl, "unknown %s field", type);
1943         return OFPERR_OFPBAC_BAD_SET_TYPE;
1944     } else if (!sf->n_bits) {
1945         VLOG_WARN_RL(&rl, "zero bit %s field %s", type, sf->field->name);
1946         return OFPERR_OFPBAC_BAD_SET_LEN;
1947     } else if (sf->ofs >= sf->field->n_bits) {
1948         VLOG_WARN_RL(&rl, "bit offset %d exceeds %d-bit width of %s field %s",
1949                      sf->ofs, sf->field->n_bits, type, sf->field->name);
1950         return OFPERR_OFPBAC_BAD_SET_LEN;
1951     } else if (sf->ofs + sf->n_bits > sf->field->n_bits) {
1952         VLOG_WARN_RL(&rl, "bit offset %d and width %d exceeds %d-bit width "
1953                      "of %s field %s", sf->ofs, sf->n_bits,
1954                      sf->field->n_bits, type, sf->field->name);
1955         return OFPERR_OFPBAC_BAD_SET_LEN;
1956     } else if (flow && !mf_are_prereqs_ok(sf->field, flow, NULL)) {
1957         VLOG_WARN_RL(&rl, "%s field %s lacks correct prerequisites",
1958                      type, sf->field->name);
1959         return OFPERR_OFPBAC_MATCH_INCONSISTENT;
1960     } else {
1961         return 0;
1962     }
1963 }
1964
1965 /* Sets all the bits in 'sf' to 1 within 'wc', if 'wc' is nonnull. */
1966 static void
1967 unwildcard_subfield(const struct mf_subfield *sf, struct flow_wildcards *wc)
1968 {
1969     if (wc) {
1970         union mf_value mask;
1971
1972         memset(&mask, 0, sizeof mask);
1973         bitwise_one(&mask, sf->field->n_bytes, sf->ofs, sf->n_bits);
1974         mf_mask_field_masked(sf->field, &mask, wc);
1975     }
1976 }
1977
1978 /* Copies 'src' into 'dst' within 'flow', and sets all the bits in 'src' and
1979  * 'dst' to 1s in 'wc', if 'wc' is nonnull.
1980  *
1981  * 'src' and 'dst' may overlap. */
1982 void
1983 mf_subfield_copy(const struct mf_subfield *src,
1984                  const struct mf_subfield *dst,
1985                  struct flow *flow, struct flow_wildcards *wc)
1986 {
1987     ovs_assert(src->n_bits == dst->n_bits);
1988     if (mf_are_prereqs_ok(dst->field, flow, wc)
1989         && mf_are_prereqs_ok(src->field, flow, wc)) {
1990         unwildcard_subfield(src, wc);
1991         unwildcard_subfield(dst, wc);
1992
1993         union mf_value src_value;
1994         union mf_value dst_value;
1995         mf_get_value(dst->field, flow, &dst_value);
1996         mf_get_value(src->field, flow, &src_value);
1997         bitwise_copy(&src_value, src->field->n_bytes, src->ofs,
1998                      &dst_value, dst->field->n_bytes, dst->ofs,
1999                      src->n_bits);
2000         mf_set_flow_value(dst->field, &dst_value, flow);
2001     }
2002 }
2003
2004 /* Swaps the bits in 'src' and 'dst' within 'flow', and sets all the bits in
2005  * 'src' and 'dst' to 1s in 'wc', if 'wc' is nonnull.
2006  *
2007  * 'src' and 'dst' may overlap. */
2008 void
2009 mf_subfield_swap(const struct mf_subfield *a,
2010                  const struct mf_subfield *b,
2011                  struct flow *flow, struct flow_wildcards *wc)
2012 {
2013     ovs_assert(a->n_bits == b->n_bits);
2014     if (mf_are_prereqs_ok(a->field, flow, wc)
2015         && mf_are_prereqs_ok(b->field, flow, wc)) {
2016         unwildcard_subfield(a, wc);
2017         unwildcard_subfield(b, wc);
2018
2019         union mf_value a_value;
2020         union mf_value b_value;
2021         mf_get_value(a->field, flow, &a_value);
2022         mf_get_value(b->field, flow, &b_value);
2023         union mf_value b2_value = b_value;
2024
2025         /* Copy 'a' into 'b'. */
2026         bitwise_copy(&a_value, a->field->n_bytes, a->ofs,
2027                      &b_value, b->field->n_bytes, b->ofs,
2028                      a->n_bits);
2029         mf_set_flow_value(b->field, &b_value, flow);
2030
2031         /* Copy original 'b' into 'a'. */
2032         bitwise_copy(&b2_value, b->field->n_bytes, b->ofs,
2033                      &a_value, a->field->n_bytes, a->ofs,
2034                      b->n_bits);
2035         mf_set_flow_value(a->field, &a_value, flow);
2036     }
2037 }
2038
2039 /* Checks whether 'sf' is valid for reading a subfield out of 'flow'.  Returns
2040  * 0 if so, otherwise an OpenFlow error code (e.g. as returned by
2041  * ofp_mkerr()).  */
2042 enum ofperr
2043 mf_check_src(const struct mf_subfield *sf, const struct flow *flow)
2044 {
2045     return mf_check__(sf, flow, "source");
2046 }
2047
2048 /* Checks whether 'sf' is valid for writing a subfield into 'flow'.  Returns 0
2049  * if so, otherwise an OpenFlow error code (e.g. as returned by
2050  * ofp_mkerr()). */
2051 enum ofperr
2052 mf_check_dst(const struct mf_subfield *sf, const struct flow *flow)
2053 {
2054     int error = mf_check__(sf, flow, "destination");
2055     if (!error && !sf->field->writable) {
2056         VLOG_WARN_RL(&rl, "destination field %s is not writable",
2057                      sf->field->name);
2058         return OFPERR_OFPBAC_BAD_SET_ARGUMENT;
2059     }
2060     return error;
2061 }
2062
2063 /* Copies the value and wildcard bit pattern for 'mf' from 'match' into the
2064  * 'value' and 'mask', respectively. */
2065 void
2066 mf_get(const struct mf_field *mf, const struct match *match,
2067        union mf_value *value, union mf_value *mask)
2068 {
2069     mf_get_value(mf, &match->flow, value);
2070     mf_get_mask(mf, &match->wc, mask);
2071 }
2072
2073 static char *
2074 mf_from_integer_string(const struct mf_field *mf, const char *s,
2075                        uint8_t *valuep, uint8_t *maskp)
2076 {
2077     char *tail;
2078     const char *err_str = "";
2079     int err;
2080
2081     err = parse_int_string(s, valuep, mf->n_bytes, &tail);
2082     if (err || (*tail != '\0' && *tail != '/')) {
2083         err_str = "value";
2084         goto syntax_error;
2085     }
2086
2087     if (*tail == '/') {
2088         err = parse_int_string(tail + 1, maskp, mf->n_bytes, &tail);
2089         if (err || *tail != '\0') {
2090             err_str = "mask";
2091             goto syntax_error;
2092         }
2093     } else {
2094         memset(maskp, 0xff, mf->n_bytes);
2095     }
2096
2097     return NULL;
2098
2099 syntax_error:
2100     if (err == ERANGE) {
2101         return xasprintf("%s: %s too large for %u-byte field %s",
2102                          s, err_str, mf->n_bytes, mf->name);
2103     } else {
2104         return xasprintf("%s: bad syntax for %s %s", s, mf->name, err_str);
2105     }
2106 }
2107
2108 static char *
2109 mf_from_ethernet_string(const struct mf_field *mf, const char *s,
2110                         struct eth_addr *mac, struct eth_addr *mask)
2111 {
2112     int n;
2113
2114     ovs_assert(mf->n_bytes == ETH_ADDR_LEN);
2115
2116     n = -1;
2117     if (ovs_scan(s, ETH_ADDR_SCAN_FMT"%n", ETH_ADDR_SCAN_ARGS(*mac), &n)
2118         && n == strlen(s)) {
2119         *mask = eth_addr_exact;
2120         return NULL;
2121     }
2122
2123     n = -1;
2124     if (ovs_scan(s, ETH_ADDR_SCAN_FMT"/"ETH_ADDR_SCAN_FMT"%n",
2125                  ETH_ADDR_SCAN_ARGS(*mac), ETH_ADDR_SCAN_ARGS(*mask), &n)
2126         && n == strlen(s)) {
2127         return NULL;
2128     }
2129
2130     return xasprintf("%s: invalid Ethernet address", s);
2131 }
2132
2133 static char *
2134 mf_from_ipv4_string(const struct mf_field *mf, const char *s,
2135                     ovs_be32 *ip, ovs_be32 *mask)
2136 {
2137     ovs_assert(mf->n_bytes == sizeof *ip);
2138     return ip_parse_masked(s, ip, mask);
2139 }
2140
2141 static char *
2142 mf_from_ipv6_string(const struct mf_field *mf, const char *s,
2143                     struct in6_addr *ipv6, struct in6_addr *mask)
2144 {
2145     ovs_assert(mf->n_bytes == sizeof *ipv6);
2146     return ipv6_parse_masked(s, ipv6, mask);
2147 }
2148
2149 static char *
2150 mf_from_ofp_port_string(const struct mf_field *mf, const char *s,
2151                         ovs_be16 *valuep, ovs_be16 *maskp)
2152 {
2153     ofp_port_t port;
2154
2155     ovs_assert(mf->n_bytes == sizeof(ovs_be16));
2156
2157     if (ofputil_port_from_string(s, &port)) {
2158         *valuep = htons(ofp_to_u16(port));
2159         *maskp = OVS_BE16_MAX;
2160         return NULL;
2161     }
2162     return xasprintf("%s: port value out of range for %s", s, mf->name);
2163 }
2164
2165 static char *
2166 mf_from_ofp_port_string32(const struct mf_field *mf, const char *s,
2167                           ovs_be32 *valuep, ovs_be32 *maskp)
2168 {
2169     ofp_port_t port;
2170
2171     ovs_assert(mf->n_bytes == sizeof(ovs_be32));
2172     if (ofputil_port_from_string(s, &port)) {
2173         *valuep = ofputil_port_to_ofp11(port);
2174         *maskp = OVS_BE32_MAX;
2175         return NULL;
2176     }
2177     return xasprintf("%s: port value out of range for %s", s, mf->name);
2178 }
2179
2180 struct frag_handling {
2181     const char *name;
2182     uint8_t mask;
2183     uint8_t value;
2184 };
2185
2186 static const struct frag_handling all_frags[] = {
2187 #define A FLOW_NW_FRAG_ANY
2188 #define L FLOW_NW_FRAG_LATER
2189     /* name               mask  value */
2190
2191     { "no",               A|L,  0     },
2192     { "first",            A|L,  A     },
2193     { "later",            A|L,  A|L   },
2194
2195     { "no",               A,    0     },
2196     { "yes",              A,    A     },
2197
2198     { "not_later",        L,    0     },
2199     { "later",            L,    L     },
2200 #undef A
2201 #undef L
2202 };
2203
2204 static char *
2205 mf_from_frag_string(const char *s, uint8_t *valuep, uint8_t *maskp)
2206 {
2207     const struct frag_handling *h;
2208
2209     for (h = all_frags; h < &all_frags[ARRAY_SIZE(all_frags)]; h++) {
2210         if (!strcasecmp(s, h->name)) {
2211             /* We force the upper bits of the mask on to make mf_parse_value()
2212              * happy (otherwise it will never think it's an exact match.) */
2213             *maskp = h->mask | ~FLOW_NW_FRAG_MASK;
2214             *valuep = h->value;
2215             return NULL;
2216         }
2217     }
2218
2219     return xasprintf("%s: unknown fragment type (valid types are \"no\", "
2220                      "\"yes\", \"first\", \"later\", \"not_first\"", s);
2221 }
2222
2223 static char *
2224 parse_mf_flags(const char *s, const char *(*bit_to_string)(uint32_t),
2225                const char *field_name, ovs_be16 *flagsp, ovs_be16 allowed,
2226                ovs_be16 *maskp)
2227 {
2228     int err;
2229     char *err_str;
2230     uint32_t flags, mask;
2231
2232     err = parse_flags(s, bit_to_string, '\0', field_name, &err_str,
2233                       &flags, ntohs(allowed), maskp ? &mask : NULL);
2234     if (err < 0) {
2235         return err_str;
2236     }
2237
2238     *flagsp = htons(flags);
2239     if (maskp) {
2240         *maskp = htons(mask);
2241     }
2242
2243     return NULL;
2244 }
2245
2246 static char *
2247 mf_from_tcp_flags_string(const char *s, ovs_be16 *flagsp, ovs_be16 *maskp)
2248 {
2249     return parse_mf_flags(s, packet_tcp_flag_to_string, "TCP", flagsp,
2250                           TCP_FLAGS_BE16(OVS_BE16_MAX), maskp);
2251 }
2252
2253 static char *
2254 mf_from_tun_flags_string(const char *s, ovs_be16 *flagsp, ovs_be16 *maskp)
2255 {
2256     return parse_mf_flags(s, flow_tun_flag_to_string, "tunnel", flagsp,
2257                           htons(FLOW_TNL_PUB_F_MASK), maskp);
2258 }
2259
2260 static char *
2261 mf_from_ct_state_string(const char *s, ovs_be32 *flagsp, ovs_be32 *maskp)
2262 {
2263     int err;
2264     char *err_str;
2265     uint32_t flags, mask;
2266
2267     err = parse_flags(s, ct_state_to_string, '\0', "ct_state", &err_str,
2268                       &flags, CS_SUPPORTED_MASK, maskp ? &mask : NULL);
2269     if (err < 0) {
2270         return err_str;
2271     }
2272
2273     *flagsp = htonl(flags);
2274     if (maskp) {
2275         *maskp = htonl(mask);
2276     }
2277
2278     return NULL;
2279 }
2280
2281 /* Parses 's', a string value for field 'mf', into 'value' and 'mask'.  Returns
2282  * NULL if successful, otherwise a malloc()'d string describing the error. */
2283 char *
2284 mf_parse(const struct mf_field *mf, const char *s,
2285          union mf_value *value, union mf_value *mask)
2286 {
2287     char *error;
2288
2289     if (!strcmp(s, "*")) {
2290         memset(value, 0, mf->n_bytes);
2291         memset(mask, 0, mf->n_bytes);
2292         return NULL;
2293     }
2294
2295     switch (mf->string) {
2296     case MFS_DECIMAL:
2297     case MFS_HEXADECIMAL:
2298         error = mf_from_integer_string(mf, s,
2299                                        (uint8_t *) value, (uint8_t *) mask);
2300         break;
2301
2302     case MFS_CT_STATE:
2303         ovs_assert(mf->n_bytes == sizeof(ovs_be32));
2304         error = mf_from_ct_state_string(s, &value->be32, &mask->be32);
2305         break;
2306
2307     case MFS_ETHERNET:
2308         error = mf_from_ethernet_string(mf, s, &value->mac, &mask->mac);
2309         break;
2310
2311     case MFS_IPV4:
2312         error = mf_from_ipv4_string(mf, s, &value->be32, &mask->be32);
2313         break;
2314
2315     case MFS_IPV6:
2316         error = mf_from_ipv6_string(mf, s, &value->ipv6, &mask->ipv6);
2317         break;
2318
2319     case MFS_OFP_PORT:
2320         error = mf_from_ofp_port_string(mf, s, &value->be16, &mask->be16);
2321         break;
2322
2323     case MFS_OFP_PORT_OXM:
2324         error = mf_from_ofp_port_string32(mf, s, &value->be32, &mask->be32);
2325         break;
2326
2327     case MFS_FRAG:
2328         error = mf_from_frag_string(s, &value->u8, &mask->u8);
2329         break;
2330
2331     case MFS_TNL_FLAGS:
2332         ovs_assert(mf->n_bytes == sizeof(ovs_be16));
2333         error = mf_from_tun_flags_string(s, &value->be16, &mask->be16);
2334         break;
2335
2336     case MFS_TCP_FLAGS:
2337         ovs_assert(mf->n_bytes == sizeof(ovs_be16));
2338         error = mf_from_tcp_flags_string(s, &value->be16, &mask->be16);
2339         break;
2340
2341     default:
2342         OVS_NOT_REACHED();
2343     }
2344
2345     if (!error && !mf_is_mask_valid(mf, mask)) {
2346         error = xasprintf("%s: invalid mask for field %s", s, mf->name);
2347     }
2348     return error;
2349 }
2350
2351 /* Parses 's', a string value for field 'mf', into 'value'.  Returns NULL if
2352  * successful, otherwise a malloc()'d string describing the error. */
2353 char *
2354 mf_parse_value(const struct mf_field *mf, const char *s, union mf_value *value)
2355 {
2356     union mf_value mask;
2357     char *error;
2358
2359     error = mf_parse(mf, s, value, &mask);
2360     if (error) {
2361         return error;
2362     }
2363
2364     if (!is_all_ones((const uint8_t *) &mask, mf->n_bytes)) {
2365         return xasprintf("%s: wildcards not allowed here", s);
2366     }
2367     return NULL;
2368 }
2369
2370 static void
2371 mf_format_integer_string(const struct mf_field *mf, const uint8_t *valuep,
2372                          const uint8_t *maskp, struct ds *s)
2373 {
2374     if (mf->string == MFS_HEXADECIMAL) {
2375         ds_put_hex(s, valuep, mf->n_bytes);
2376     } else {
2377         unsigned long long int integer = 0;
2378         int i;
2379
2380         ovs_assert(mf->n_bytes <= 8);
2381         for (i = 0; i < mf->n_bytes; i++) {
2382             integer = (integer << 8) | valuep[i];
2383         }
2384         ds_put_format(s, "%lld", integer);
2385     }
2386
2387     if (maskp) {
2388         /* I guess we could write the mask in decimal for MFS_DECIMAL but I'm
2389          * not sure that that a bit-mask written in decimal is ever easier to
2390          * understand than the same bit-mask written in hexadecimal. */
2391         ds_put_char(s, '/');
2392         ds_put_hex(s, maskp, mf->n_bytes);
2393     }
2394 }
2395
2396 static void
2397 mf_format_frag_string(uint8_t value, uint8_t mask, struct ds *s)
2398 {
2399     const struct frag_handling *h;
2400
2401     mask &= FLOW_NW_FRAG_MASK;
2402     value &= mask;
2403
2404     for (h = all_frags; h < &all_frags[ARRAY_SIZE(all_frags)]; h++) {
2405         if (value == h->value && mask == h->mask) {
2406             ds_put_cstr(s, h->name);
2407             return;
2408         }
2409     }
2410     ds_put_cstr(s, "<error>");
2411 }
2412
2413 static void
2414 mf_format_tnl_flags_string(ovs_be16 value, ovs_be16 mask, struct ds *s)
2415 {
2416     format_flags_masked(s, NULL, flow_tun_flag_to_string, ntohs(value),
2417                         ntohs(mask) & FLOW_TNL_PUB_F_MASK, FLOW_TNL_PUB_F_MASK);
2418 }
2419
2420 static void
2421 mf_format_tcp_flags_string(ovs_be16 value, ovs_be16 mask, struct ds *s)
2422 {
2423     format_flags_masked(s, NULL, packet_tcp_flag_to_string, ntohs(value),
2424                         TCP_FLAGS(mask), TCP_FLAGS(OVS_BE16_MAX));
2425 }
2426
2427 static void
2428 mf_format_ct_state_string(ovs_be32 value, ovs_be32 mask, struct ds *s)
2429 {
2430     format_flags_masked(s, NULL, ct_state_to_string, ntohl(value),
2431                         ntohl(mask), UINT16_MAX);
2432 }
2433
2434 /* Appends to 's' a string representation of field 'mf' whose value is in
2435  * 'value' and 'mask'.  'mask' may be NULL to indicate an exact match. */
2436 void
2437 mf_format(const struct mf_field *mf,
2438           const union mf_value *value, const union mf_value *mask,
2439           struct ds *s)
2440 {
2441     if (mask) {
2442         if (is_all_zeros(mask, mf->n_bytes)) {
2443             ds_put_cstr(s, "ANY");
2444             return;
2445         } else if (is_all_ones(mask, mf->n_bytes)) {
2446             mask = NULL;
2447         }
2448     }
2449
2450     switch (mf->string) {
2451     case MFS_OFP_PORT_OXM:
2452         if (!mask) {
2453             ofp_port_t port;
2454             ofputil_port_from_ofp11(value->be32, &port);
2455             ofputil_format_port(port, s);
2456             break;
2457         }
2458         /* fall through */
2459     case MFS_OFP_PORT:
2460         if (!mask) {
2461             ofputil_format_port(u16_to_ofp(ntohs(value->be16)), s);
2462             break;
2463         }
2464         /* fall through */
2465     case MFS_DECIMAL:
2466     case MFS_HEXADECIMAL:
2467         mf_format_integer_string(mf, (uint8_t *) value, (uint8_t *) mask, s);
2468         break;
2469
2470     case MFS_CT_STATE:
2471         mf_format_ct_state_string(value->be32,
2472                                   mask ? mask->be32 : OVS_BE32_MAX, s);
2473         break;
2474
2475     case MFS_ETHERNET:
2476         eth_format_masked(value->mac, mask ? &mask->mac : NULL, s);
2477         break;
2478
2479     case MFS_IPV4:
2480         ip_format_masked(value->be32, mask ? mask->be32 : OVS_BE32_MAX, s);
2481         break;
2482
2483     case MFS_IPV6:
2484         ipv6_format_masked(&value->ipv6, mask ? &mask->ipv6 : NULL, s);
2485         break;
2486
2487     case MFS_FRAG:
2488         mf_format_frag_string(value->u8, mask ? mask->u8 : UINT8_MAX, s);
2489         break;
2490
2491     case MFS_TNL_FLAGS:
2492         mf_format_tnl_flags_string(value->be16,
2493                                    mask ? mask->be16 : OVS_BE16_MAX, s);
2494         break;
2495
2496     case MFS_TCP_FLAGS:
2497         mf_format_tcp_flags_string(value->be16,
2498                                    mask ? mask->be16 : OVS_BE16_MAX, s);
2499         break;
2500
2501     default:
2502         OVS_NOT_REACHED();
2503     }
2504 }
2505 \f
2506 /* Makes subfield 'sf' within 'flow' exactly match the 'sf->n_bits'
2507  * least-significant bits in 'x'.
2508  */
2509 void
2510 mf_write_subfield_flow(const struct mf_subfield *sf,
2511                        const union mf_subvalue *x, struct flow *flow)
2512 {
2513     const struct mf_field *field = sf->field;
2514     union mf_value value;
2515
2516     mf_get_value(field, flow, &value);
2517     bitwise_copy(x, sizeof *x, 0, &value, field->n_bytes,
2518                  sf->ofs, sf->n_bits);
2519     mf_set_flow_value(field, &value, flow);
2520 }
2521
2522 /* Makes subfield 'sf' within 'match' exactly match the 'sf->n_bits'
2523  * least-significant bits in 'x'.
2524  */
2525 void
2526 mf_write_subfield(const struct mf_subfield *sf, const union mf_subvalue *x,
2527                   struct match *match)
2528 {
2529     const struct mf_field *field = sf->field;
2530     union mf_value value, mask;
2531
2532     mf_get(field, match, &value, &mask);
2533     bitwise_copy(x, sizeof *x, 0, &value, field->n_bytes, sf->ofs, sf->n_bits);
2534     bitwise_one (                 &mask,  field->n_bytes, sf->ofs, sf->n_bits);
2535     mf_set(field, &value, &mask, match, NULL);
2536 }
2537
2538 void
2539 mf_write_subfield_value(const struct mf_subfield *sf, const void *src,
2540                         struct match *match)
2541 {
2542     const struct mf_field *field = sf->field;
2543     union mf_value value, mask;
2544     unsigned int size = DIV_ROUND_UP(sf->n_bits, 8);
2545
2546     mf_get(field, match, &value, &mask);
2547     bitwise_copy(src, size, 0, &value, field->n_bytes, sf->ofs, sf->n_bits);
2548     bitwise_one (              &mask,  field->n_bytes, sf->ofs, sf->n_bits);
2549     mf_set(field, &value, &mask, match, NULL);
2550 }
2551
2552 /* 'v' and 'm' correspond to values of 'field'.  This function copies them into
2553  * 'match' in the correspond positions. */
2554 void
2555 mf_mask_subfield(const struct mf_field *field,
2556                  const union mf_subvalue *v,
2557                  const union mf_subvalue *m,
2558                  struct match *match)
2559 {
2560     union mf_value value, mask;
2561
2562     mf_get(field, match, &value, &mask);
2563     bitwise_copy(v, sizeof *v, 0, &value, field->n_bytes, 0, field->n_bits);
2564     bitwise_copy(m, sizeof *m, 0, &mask,  field->n_bytes, 0, field->n_bits);
2565     mf_set(field, &value, &mask, match, NULL);
2566 }
2567
2568 /* Initializes 'x' to the value of 'sf' within 'flow'.  'sf' must be valid for
2569  * reading 'flow', e.g. as checked by mf_check_src(). */
2570 void
2571 mf_read_subfield(const struct mf_subfield *sf, const struct flow *flow,
2572                  union mf_subvalue *x)
2573 {
2574     union mf_value value;
2575
2576     mf_get_value(sf->field, flow, &value);
2577
2578     memset(x, 0, sizeof *x);
2579     bitwise_copy(&value, sf->field->n_bytes, sf->ofs,
2580                  x, sizeof *x, 0,
2581                  sf->n_bits);
2582 }
2583
2584 /* Returns the value of 'sf' within 'flow'.  'sf' must be valid for reading
2585  * 'flow', e.g. as checked by mf_check_src() and sf->n_bits must be 64 or
2586  * less. */
2587 uint64_t
2588 mf_get_subfield(const struct mf_subfield *sf, const struct flow *flow)
2589 {
2590     union mf_value value;
2591
2592     mf_get_value(sf->field, flow, &value);
2593     return bitwise_get(&value, sf->field->n_bytes, sf->ofs, sf->n_bits);
2594 }
2595
2596 void
2597 mf_format_subvalue(const union mf_subvalue *subvalue, struct ds *s)
2598 {
2599     ds_put_hex(s, subvalue->u8, sizeof subvalue->u8);
2600 }
2601
2602 void
2603 field_array_set(enum mf_field_id id, const union mf_value *value,
2604                 struct field_array *fa)
2605 {
2606     size_t i, offset = 0;
2607
2608     ovs_assert(id < MFF_N_IDS);
2609
2610     /* Find the spot for 'id'. */
2611     BITMAP_FOR_EACH_1 (i, id, fa->used.bm) {
2612         offset += mf_from_id(i)->n_bytes;
2613     }
2614
2615     size_t value_size = mf_from_id(id)->n_bytes;
2616
2617     /* make room if necessary. */
2618     if (!bitmap_is_set(fa->used.bm, id)) {
2619         fa->values = xrealloc(fa->values, fa->values_size + value_size);
2620         /* Move remainder forward, if any. */
2621         if (offset < fa->values_size) {
2622             memmove(fa->values + offset + value_size, fa->values + offset,
2623                     fa->values_size - offset);
2624         }
2625         fa->values_size += value_size;
2626     }
2627     bitmap_set1(fa->used.bm, id);
2628
2629     memcpy(fa->values + offset, value, value_size);
2630 }