lib/meta-flow.c

   1 /*
   2  * Copyright (c) 2011, 2012 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 "meta-flow.h"
  20
  21 #include <assert.h>
  22 #include <errno.h>
  23 #include <limits.h>
  24 #include <netinet/icmp6.h>
  25 #include <netinet/ip6.h>
  26
  27 #include "classifier.h"
  28 #include "dynamic-string.h"
  29 #include "ofp-errors.h"
  30 #include "ofp-util.h"
  31 #include "packets.h"
  32 #include "random.h"
  33 #include "shash.h"
  34 #include "socket-util.h"
  35 #include "unaligned.h"
  36 #include "vlog.h"
  37
  38 VLOG_DEFINE_THIS_MODULE(meta_flow);
  39
  40 #define MF_FIELD_SIZES(MEMBER)                  \
  41     sizeof ((union mf_value *)0)->MEMBER,       \
  42     8 * sizeof ((union mf_value *)0)->MEMBER
  43
  44 static const struct mf_field mf_fields[MFF_N_IDS] = {
  45     /* ## -------- ## */
  46     /* ## metadata ## */
  47     /* ## -------- ## */
  48
  49     {
  50         MFF_TUN_ID, "tun_id", NULL,
  51         MF_FIELD_SIZES(be64),
  52         MFM_FULLY,
  53         MFS_HEXADECIMAL,
  54         MFP_NONE,
  55         true,
  56         NXM_NX_TUN_ID, "NXM_NX_TUN_ID",
  57         NXM_NX_TUN_ID, "NXM_NX_TUN_ID",
  58     }, {
  59         MFF_METADATA, "metadata", NULL,
  60         MF_FIELD_SIZES(be64),
  61         MFM_FULLY,
  62         MFS_HEXADECIMAL,
  63         MFP_NONE,
  64         true,
  65         OXM_OF_METADATA, "OXM_OF_METADATA",
  66         OXM_OF_METADATA, "OXM_OF_METADATA",
  67     }, {
  68         MFF_IN_PORT, "in_port", NULL,
  69         MF_FIELD_SIZES(be16),
  70         MFM_NONE,
  71         MFS_OFP_PORT,
  72         MFP_NONE,
  73         false,
  74         NXM_OF_IN_PORT, "NXM_OF_IN_PORT",
  75         OXM_OF_IN_PORT, "OXM_OF_IN_PORT",
  76     },
  77
  78 #define REGISTER(IDX)                           \
  79     {                                           \
  80         MFF_REG##IDX, "reg" #IDX, NULL,         \
  81         MF_FIELD_SIZES(be32),                   \
  82         MFM_FULLY,                              \
  83         MFS_HEXADECIMAL,                        \
  84         MFP_NONE,                               \
  85         true,                                   \
  86         NXM_NX_REG(IDX), "NXM_NX_REG" #IDX,     \
  87         NXM_NX_REG(IDX), "NXM_NX_REG" #IDX,     \
  88     }
  89 #if FLOW_N_REGS > 0
  90     REGISTER(0),
  91 #endif
  92 #if FLOW_N_REGS > 1
  93     REGISTER(1),
  94 #endif
  95 #if FLOW_N_REGS > 2
  96     REGISTER(2),
  97 #endif
  98 #if FLOW_N_REGS > 3
  99     REGISTER(3),
 100 #endif
 101 #if FLOW_N_REGS > 4
 102     REGISTER(4),
 103 #endif
 104 #if FLOW_N_REGS > 5
 105     REGISTER(5),
 106 #endif
 107 #if FLOW_N_REGS > 6
 108     REGISTER(6),
 109 #endif
 110 #if FLOW_N_REGS > 7
 111     REGISTER(7),
 112 #endif
 113 #if FLOW_N_REGS > 8
 114 #error
 115 #endif
 116
 117     /* ## -- ## */
 118     /* ## L2 ## */
 119     /* ## -- ## */
 120
 121     {
 122         MFF_ETH_SRC, "eth_src", "dl_src",
 123         MF_FIELD_SIZES(mac),
 124         MFM_FULLY,
 125         MFS_ETHERNET,
 126         MFP_NONE,
 127         true,
 128         NXM_OF_ETH_SRC, "NXM_OF_ETH_SRC",
 129         OXM_OF_ETH_SRC, "OXM_OF_ETH_SRC",
 130     }, {
 131         MFF_ETH_DST, "eth_dst", "dl_dst",
 132         MF_FIELD_SIZES(mac),
 133         MFM_FULLY,
 134         MFS_ETHERNET,
 135         MFP_NONE,
 136         true,
 137         NXM_OF_ETH_DST, "NXM_OF_ETH_DST",
 138         OXM_OF_ETH_DST, "OXM_OF_ETH_DST",
 139     }, {
 140         MFF_ETH_TYPE, "eth_type", "dl_type",
 141         MF_FIELD_SIZES(be16),
 142         MFM_NONE,
 143         MFS_HEXADECIMAL,
 144         MFP_NONE,
 145         false,
 146         NXM_OF_ETH_TYPE, "NXM_OF_ETH_TYPE",
 147         OXM_OF_ETH_TYPE, "OXM_OF_ETH_TYPE",
 148     },
 149
 150     {
 151         MFF_VLAN_TCI, "vlan_tci", NULL,
 152         MF_FIELD_SIZES(be16),
 153         MFM_FULLY,
 154         MFS_HEXADECIMAL,
 155         MFP_NONE,
 156         true,
 157         NXM_OF_VLAN_TCI, "NXM_OF_VLAN_TCI",
 158         NXM_OF_VLAN_TCI, "NXM_OF_VLAN_TCI",
 159     }, {
 160         MFF_DL_VLAN, "dl_vlan", NULL,
 161         sizeof(ovs_be16), 12,
 162         MFM_NONE,
 163         MFS_DECIMAL,
 164         MFP_NONE,
 165         true,
 166         0, NULL,
 167         0, NULL,
 168     }, {
 169         MFF_VLAN_VID, "vlan_vid", NULL,
 170         sizeof(ovs_be16), 12,
 171         MFM_FULLY,
 172         MFS_DECIMAL,
 173         MFP_NONE,
 174         true,
 175         OXM_OF_VLAN_VID, "OXM_OF_VLAN_VID",
 176         OXM_OF_VLAN_VID, "OXM_OF_VLAN_VID",
 177     }, {
 178         MFF_DL_VLAN_PCP, "dl_vlan_pcp", NULL,
 179         1, 3,
 180         MFM_NONE,
 181         MFS_DECIMAL,
 182         MFP_NONE,
 183         true,
 184         0, NULL,
 185         0, NULL,
 186     }, {
 187         MFF_VLAN_PCP, "vlan_pcp", NULL,
 188         1, 3,
 189         MFM_NONE,
 190         MFS_DECIMAL,
 191         MFP_VLAN_VID,
 192         true,
 193         OXM_OF_VLAN_PCP, "OXM_OF_VLAN_PCP",
 194         OXM_OF_VLAN_PCP, "OXM_OF_VLAN_PCP",
 195     },
 196
 197     /* ## -- ## */
 198     /* ## L3 ## */
 199     /* ## -- ## */
 200
 201     {
 202         MFF_IPV4_SRC, "ip_src", "nw_src",
 203         MF_FIELD_SIZES(be32),
 204         MFM_FULLY,
 205         MFS_IPV4,
 206         MFP_IPV4,
 207         true,
 208         NXM_OF_IP_SRC, "NXM_OF_IP_SRC",
 209         OXM_OF_IPV4_SRC, "OXM_OF_IPV4_SRC",
 210     }, {
 211         MFF_IPV4_DST, "ip_dst", "nw_dst",
 212         MF_FIELD_SIZES(be32),
 213         MFM_FULLY,
 214         MFS_IPV4,
 215         MFP_IPV4,
 216         true,
 217         NXM_OF_IP_DST, "NXM_OF_IP_DST",
 218         OXM_OF_IPV4_DST, "OXM_OF_IPV4_DST",
 219     },
 220
 221     {
 222         MFF_IPV6_SRC, "ipv6_src", NULL,
 223         MF_FIELD_SIZES(ipv6),
 224         MFM_FULLY,
 225         MFS_IPV6,
 226         MFP_IPV6,
 227         true,
 228         NXM_NX_IPV6_SRC, "NXM_NX_IPV6_SRC",
 229         OXM_OF_IPV6_SRC, "OXM_OF_IPV6_SRC",
 230     }, {
 231         MFF_IPV6_DST, "ipv6_dst", NULL,
 232         MF_FIELD_SIZES(ipv6),
 233         MFM_FULLY,
 234         MFS_IPV6,
 235         MFP_IPV6,
 236         true,
 237         NXM_NX_IPV6_DST, "NXM_NX_IPV6_DST",
 238         OXM_OF_IPV6_DST, "OXM_OF_IPV6_DST",
 239     },
 240     {
 241         MFF_IPV6_LABEL, "ipv6_label", NULL,
 242         4, 20,
 243         MFM_FULLY,
 244         MFS_HEXADECIMAL,
 245         MFP_IPV6,
 246         false,
 247         NXM_NX_IPV6_LABEL, "NXM_NX_IPV6_LABEL",
 248         OXM_OF_IPV6_FLABEL, "OXM_OF_IPV6_FLABEL",
 249     },
 250
 251     {
 252         MFF_IP_PROTO, "nw_proto", NULL,
 253         MF_FIELD_SIZES(u8),
 254         MFM_NONE,
 255         MFS_DECIMAL,
 256         MFP_IP_ANY,
 257         false,
 258         NXM_OF_IP_PROTO, "NXM_OF_IP_PROTO",
 259         OXM_OF_IP_PROTO, "OXM_OF_IP_PROTO",
 260     }, {
 261         MFF_IP_DSCP, "nw_tos", NULL,
 262         MF_FIELD_SIZES(u8),
 263         MFM_NONE,
 264         MFS_DECIMAL,
 265         MFP_IP_ANY,
 266         true,
 267         NXM_OF_IP_TOS, "NXM_OF_IP_TOS",
 268         OXM_OF_IP_DSCP, "OXM_OF_IP_DSCP",
 269     }, {
 270         MFF_IP_ECN, "nw_ecn", NULL,
 271         1, 2,
 272         MFM_NONE,
 273         MFS_DECIMAL,
 274         MFP_IP_ANY,
 275         true,
 276         NXM_NX_IP_ECN, "NXM_NX_IP_ECN",
 277         OXM_OF_IP_ECN, "OXM_OF_IP_ECN",
 278     }, {
 279         MFF_IP_TTL, "nw_ttl", NULL,
 280         MF_FIELD_SIZES(u8),
 281         MFM_NONE,
 282         MFS_DECIMAL,
 283         MFP_IP_ANY,
 284         true,
 285         NXM_NX_IP_TTL, "NXM_NX_IP_TTL",
 286         NXM_NX_IP_TTL, "NXM_NX_IP_TTL",
 287     }, {
 288         MFF_IP_FRAG, "ip_frag", NULL,
 289         1, 2,
 290         MFM_FULLY,
 291         MFS_FRAG,
 292         MFP_IP_ANY,
 293         false,
 294         NXM_NX_IP_FRAG, "NXM_NX_IP_FRAG",
 295         NXM_NX_IP_FRAG, "NXM_NX_IP_FRAG",
 296     },
 297
 298     {
 299         MFF_ARP_OP, "arp_op", NULL,
 300         MF_FIELD_SIZES(be16),
 301         MFM_NONE,
 302         MFS_DECIMAL,
 303         MFP_ARP,
 304         false,
 305         NXM_OF_ARP_OP, "NXM_OF_ARP_OP",
 306         OXM_OF_ARP_OP, "OXM_OF_ARP_OP",
 307     }, {
 308         MFF_ARP_SPA, "arp_spa", NULL,
 309         MF_FIELD_SIZES(be32),
 310         MFM_FULLY,
 311         MFS_IPV4,
 312         MFP_ARP,
 313         false,
 314         NXM_OF_ARP_SPA, "NXM_OF_ARP_SPA",
 315         OXM_OF_ARP_SPA, "OXM_OF_ARP_SPA",
 316     }, {
 317         MFF_ARP_TPA, "arp_tpa", NULL,
 318         MF_FIELD_SIZES(be32),
 319         MFM_FULLY,
 320         MFS_IPV4,
 321         MFP_ARP,
 322         false,
 323         NXM_OF_ARP_TPA, "NXM_OF_ARP_TPA",
 324         OXM_OF_ARP_TPA, "OXM_OF_ARP_TPA",
 325     }, {
 326         MFF_ARP_SHA, "arp_sha", NULL,
 327         MF_FIELD_SIZES(mac),
 328         MFM_FULLY,
 329         MFS_ETHERNET,
 330         MFP_ARP,
 331         false,
 332         NXM_NX_ARP_SHA, "NXM_NX_ARP_SHA",
 333         OXM_OF_ARP_SHA, "OXM_OF_ARP_SHA",
 334     }, {
 335         MFF_ARP_THA, "arp_tha", NULL,
 336         MF_FIELD_SIZES(mac),
 337         MFM_FULLY,
 338         MFS_ETHERNET,
 339         MFP_ARP,
 340         false,
 341         NXM_NX_ARP_THA, "NXM_NX_ARP_THA",
 342         OXM_OF_ARP_THA, "OXM_OF_ARP_THA",
 343     },
 344
 345     /* ## -- ## */
 346     /* ## L4 ## */
 347     /* ## -- ## */
 348
 349     {
 350         MFF_TCP_SRC, "tcp_src", "tp_src",
 351         MF_FIELD_SIZES(be16),
 352         MFM_FULLY,
 353         MFS_DECIMAL,
 354         MFP_TCP,
 355         true,
 356         NXM_OF_TCP_SRC, "NXM_OF_TCP_SRC",
 357         OXM_OF_TCP_SRC, "OXM_OF_TCP_SRC",
 358     }, {
 359         MFF_TCP_DST, "tcp_dst", "tp_dst",
 360         MF_FIELD_SIZES(be16),
 361         MFM_FULLY,
 362         MFS_DECIMAL,
 363         MFP_TCP,
 364         true,
 365         NXM_OF_TCP_DST, "NXM_OF_TCP_DST",
 366         OXM_OF_TCP_DST, "OXM_OF_TCP_DST",
 367     },
 368
 369     {
 370         MFF_UDP_SRC, "udp_src", NULL,
 371         MF_FIELD_SIZES(be16),
 372         MFM_FULLY,
 373         MFS_DECIMAL,
 374         MFP_UDP,
 375         true,
 376         NXM_OF_UDP_SRC, "NXM_OF_UDP_SRC",
 377         OXM_OF_UDP_SRC, "OXM_OF_UDP_SRC",
 378     }, {
 379         MFF_UDP_DST, "udp_dst", NULL,
 380         MF_FIELD_SIZES(be16),
 381         MFM_FULLY,
 382         MFS_DECIMAL,
 383         MFP_UDP,
 384         true,
 385         NXM_OF_UDP_DST, "NXM_OF_UDP_DST",
 386         OXM_OF_UDP_DST, "OXM_OF_UDP_DST",
 387     },
 388
 389     {
 390         MFF_ICMPV4_TYPE, "icmp_type", NULL,
 391         MF_FIELD_SIZES(u8),
 392         MFM_NONE,
 393         MFS_DECIMAL,
 394         MFP_ICMPV4,
 395         false,
 396         NXM_OF_ICMP_TYPE, "NXM_OF_ICMP_TYPE",
 397         OXM_OF_ICMPV4_TYPE, "OXM_OF_ICMPV4_TYPE",
 398     }, {
 399         MFF_ICMPV4_CODE, "icmp_code", NULL,
 400         MF_FIELD_SIZES(u8),
 401         MFM_NONE,
 402         MFS_DECIMAL,
 403         MFP_ICMPV4,
 404         false,
 405         NXM_OF_ICMP_CODE, "NXM_OF_ICMP_CODE",
 406         OXM_OF_ICMPV4_CODE, "OXM_OF_ICMPV4_CODE",
 407     },
 408
 409     {
 410         MFF_ICMPV6_TYPE, "icmpv6_type", NULL,
 411         MF_FIELD_SIZES(u8),
 412         MFM_NONE,
 413         MFS_DECIMAL,
 414         MFP_ICMPV6,
 415         false,
 416         NXM_NX_ICMPV6_TYPE, "NXM_NX_ICMPV6_TYPE",
 417         OXM_OF_ICMPV6_TYPE, "OXM_OF_ICMPV6_TYPE",
 418     }, {
 419         MFF_ICMPV6_CODE, "icmpv6_code", NULL,
 420         MF_FIELD_SIZES(u8),
 421         MFM_NONE,
 422         MFS_DECIMAL,
 423         MFP_ICMPV6,
 424         false,
 425         NXM_NX_ICMPV6_CODE, "NXM_NX_ICMPV6_CODE",
 426         OXM_OF_ICMPV6_CODE, "OXM_OF_ICMPV6_CODE",
 427     },
 428
 429     /* ## ---- ## */
 430     /* ## L"5" ## */
 431     /* ## ---- ## */
 432
 433     {
 434         MFF_ND_TARGET, "nd_target", NULL,
 435         MF_FIELD_SIZES(ipv6),
 436         MFM_FULLY,
 437         MFS_IPV6,
 438         MFP_ND,
 439         false,
 440         NXM_NX_ND_TARGET, "NXM_NX_ND_TARGET",
 441         OXM_OF_IPV6_ND_TARGET, "OXM_OF_IPV6_ND_TARGET",
 442     }, {
 443         MFF_ND_SLL, "nd_sll", NULL,
 444         MF_FIELD_SIZES(mac),
 445         MFM_FULLY,
 446         MFS_ETHERNET,
 447         MFP_ND_SOLICIT,
 448         false,
 449         NXM_NX_ND_SLL, "NXM_NX_ND_SLL",
 450         OXM_OF_IPV6_ND_SLL, "OXM_OF_IPV6_ND_SLL",
 451     }, {
 452         MFF_ND_TLL, "nd_tll", NULL,
 453         MF_FIELD_SIZES(mac),
 454         MFM_FULLY,
 455         MFS_ETHERNET,
 456         MFP_ND_ADVERT,
 457         false,
 458         NXM_NX_ND_TLL, "NXM_NX_ND_TLL",
 459         OXM_OF_IPV6_ND_TLL, "OXM_OF_IPV6_ND_TLL",
 460     }
 461 };
 462
 463 /* Maps an NXM or OXM header value to an mf_field. */
 464 struct nxm_field {
 465     struct hmap_node hmap_node; /* In 'all_fields' hmap. */
 466     uint32_t header;            /* NXM or OXM header value. */
 467     const struct mf_field *mf;
 468 };
 469
 470 /* Contains 'struct nxm_field's. */
 471 static struct hmap all_fields = HMAP_INITIALIZER(&all_fields);
 472
 473 /* Rate limit for parse errors.  These always indicate a bug in an OpenFlow
 474  * controller and so there's not much point in showing a lot of them. */
 475 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
 476
 477 const struct mf_field *mf_from_nxm_header__(uint32_t header);
 478
 479 /* Returns the field with the given 'id'. */
 480 const struct mf_field *
 481 mf_from_id(enum mf_field_id id)
 482 {
 483     assert((unsigned int) id < MFF_N_IDS);
 484     return &mf_fields[id];
 485 }
 486
 487 /* Returns the field with the given 'name', or a null pointer if no field has
 488  * that name. */
 489 const struct mf_field *
 490 mf_from_name(const char *name)
 491 {
 492     static struct shash mf_by_name = SHASH_INITIALIZER(&mf_by_name);
 493
 494     if (shash_is_empty(&mf_by_name)) {
 495         const struct mf_field *mf;
 496
 497         for (mf = mf_fields; mf < &mf_fields[MFF_N_IDS]; mf++) {
 498             shash_add_once(&mf_by_name, mf->name, mf);
 499             if (mf->extra_name) {
 500                 shash_add_once(&mf_by_name, mf->extra_name, mf);
 501             }
 502         }
 503     }
 504
 505     return shash_find_data(&mf_by_name, name);
 506 }
 507
 508 static void
 509 add_nxm_field(uint32_t header, const struct mf_field *mf)
 510 {
 511     struct nxm_field *f;
 512
 513     f = xmalloc(sizeof *f);
 514     hmap_insert(&all_fields, &f->hmap_node, hash_int(header, 0));
 515     f->header = header;
 516     f->mf = mf;
 517 }
 518
 519 static void
 520 nxm_init_add_field(const struct mf_field *mf, uint32_t header)
 521 {
 522     if (header) {
 523         assert(!mf_from_nxm_header__(header));
 524         add_nxm_field(header, mf);
 525         if (mf->maskable != MFM_NONE) {
 526             add_nxm_field(NXM_MAKE_WILD_HEADER(header), mf);
 527         }
 528     }
 529 }
 530
 531 static void
 532 nxm_init(void)
 533 {
 534     const struct mf_field *mf;
 535
 536     for (mf = mf_fields; mf < &mf_fields[MFF_N_IDS]; mf++) {
 537         nxm_init_add_field(mf, mf->nxm_header);
 538         if (mf->oxm_header != mf->nxm_header) {
 539             nxm_init_add_field(mf, mf->oxm_header);
 540         }
 541     }
 542 }
 543
 544 const struct mf_field *
 545 mf_from_nxm_header(uint32_t header)
 546 {
 547     if (hmap_is_empty(&all_fields)) {
 548         nxm_init();
 549     }
 550     return mf_from_nxm_header__(header);
 551 }
 552
 553 const struct mf_field *
 554 mf_from_nxm_header__(uint32_t header)
 555 {
 556     const struct nxm_field *f;
 557
 558     HMAP_FOR_EACH_IN_BUCKET (f, hmap_node, hash_int(header, 0), &all_fields) {
 559         if (f->header == header) {
 560             return f->mf;
 561         }
 562     }
 563
 564     return NULL;
 565 }
 566
 567 /* Returns true if 'wc' wildcards all the bits in field 'mf', false if 'wc'
 568  * specifies at least one bit in the field.
 569  *
 570  * The caller is responsible for ensuring that 'wc' corresponds to a flow that
 571  * meets 'mf''s prerequisites. */
 572 bool
 573 mf_is_all_wild(const struct mf_field *mf, const struct flow_wildcards *wc)
 574 {
 575     switch (mf->id) {
 576     case MFF_TUN_ID:
 577         return !wc->tun_id_mask;
 578     case MFF_METADATA:
 579         return !wc->metadata_mask;
 580     case MFF_IN_PORT:
 581         return !wc->in_port_mask;
 582     CASE_MFF_REGS:
 583         return !wc->reg_masks[mf->id - MFF_REG0];
 584
 585     case MFF_ETH_SRC:
 586         return eth_addr_is_zero(wc->dl_src_mask);
 587     case MFF_ETH_DST:
 588         return eth_addr_is_zero(wc->dl_dst_mask);
 589     case MFF_ETH_TYPE:
 590         return !wc->dl_type_mask;
 591
 592     case MFF_ARP_SHA:
 593     case MFF_ND_SLL:
 594         return eth_addr_is_zero(wc->arp_sha_mask);
 595
 596     case MFF_ARP_THA:
 597     case MFF_ND_TLL:
 598         return eth_addr_is_zero(wc->arp_tha_mask);
 599
 600     case MFF_VLAN_TCI:
 601         return !wc->vlan_tci_mask;
 602     case MFF_DL_VLAN:
 603         return !(wc->vlan_tci_mask & htons(VLAN_VID_MASK));
 604     case MFF_VLAN_VID:
 605         return !(wc->vlan_tci_mask & htons(VLAN_VID_MASK | VLAN_CFI));
 606     case MFF_DL_VLAN_PCP:
 607     case MFF_VLAN_PCP:
 608         return !(wc->vlan_tci_mask & htons(VLAN_PCP_MASK));
 609
 610     case MFF_IPV4_SRC:
 611         return !wc->nw_src_mask;
 612     case MFF_IPV4_DST:
 613         return !wc->nw_dst_mask;
 614
 615     case MFF_IPV6_SRC:
 616         return ipv6_mask_is_any(&wc->ipv6_src_mask);
 617     case MFF_IPV6_DST:
 618         return ipv6_mask_is_any(&wc->ipv6_dst_mask);
 619
 620     case MFF_IPV6_LABEL:
 621         return !wc->ipv6_label_mask;
 622
 623     case MFF_IP_PROTO:
 624         return !wc->nw_proto_mask;
 625     case MFF_IP_DSCP:
 626         return !(wc->nw_tos_mask & IP_DSCP_MASK);
 627     case MFF_IP_ECN:
 628         return !(wc->nw_tos_mask & IP_ECN_MASK);
 629     case MFF_IP_TTL:
 630         return !wc->nw_ttl_mask;
 631
 632     case MFF_ND_TARGET:
 633         return ipv6_mask_is_any(&wc->nd_target_mask);
 634
 635     case MFF_IP_FRAG:
 636         return !(wc->nw_frag_mask & FLOW_NW_FRAG_MASK);
 637
 638     case MFF_ARP_OP:
 639         return !wc->nw_proto_mask;
 640     case MFF_ARP_SPA:
 641         return !wc->nw_src_mask;
 642     case MFF_ARP_TPA:
 643         return !wc->nw_dst_mask;
 644
 645     case MFF_TCP_SRC:
 646     case MFF_UDP_SRC:
 647     case MFF_ICMPV4_TYPE:
 648     case MFF_ICMPV6_TYPE:
 649         return !wc->tp_src_mask;
 650     case MFF_TCP_DST:
 651     case MFF_UDP_DST:
 652     case MFF_ICMPV4_CODE:
 653     case MFF_ICMPV6_CODE:
 654         return !wc->tp_dst_mask;
 655
 656     case MFF_N_IDS:
 657     default:
 658         NOT_REACHED();
 659     }
 660 }
 661
 662 /* Initializes 'mask' with the wildcard bit pattern for field 'mf' within 'wc'.
 663  * Each bit in 'mask' will be set to 1 if the bit is significant for matching
 664  * purposes, or to 0 if it is wildcarded.
 665  *
 666  * The caller is responsible for ensuring that 'wc' corresponds to a flow that
 667  * meets 'mf''s prerequisites. */
 668 void
 669 mf_get_mask(const struct mf_field *mf, const struct flow_wildcards *wc,
 670             union mf_value *mask)
 671 {
 672     switch (mf->id) {
 673     case MFF_TUN_ID:
 674         mask->be64 = wc->tun_id_mask;
 675         break;
 676     case MFF_METADATA:
 677         mask->be64 = wc->metadata_mask;
 678         break;
 679     case MFF_IN_PORT:
 680         mask->be16 = htons(wc->in_port_mask);
 681         break;
 682     CASE_MFF_REGS:
 683         mask->be32 = htonl(wc->reg_masks[mf->id - MFF_REG0]);
 684         break;
 685
 686     case MFF_ETH_DST:
 687         memcpy(mask->mac, wc->dl_dst_mask, ETH_ADDR_LEN);
 688         break;
 689     case MFF_ETH_SRC:
 690         memcpy(mask->mac, wc->dl_src_mask, ETH_ADDR_LEN);
 691         break;
 692     case MFF_ETH_TYPE:
 693         mask->be16 = wc->dl_type_mask;
 694         break;
 695
 696     case MFF_VLAN_TCI:
 697         mask->be16 = wc->vlan_tci_mask;
 698         break;
 699     case MFF_DL_VLAN:
 700         mask->be16 = wc->vlan_tci_mask & htons(VLAN_VID_MASK);
 701         break;
 702     case MFF_VLAN_VID:
 703         mask->be16 = wc->vlan_tci_mask & htons(VLAN_VID_MASK | VLAN_CFI);
 704         break;
 705     case MFF_DL_VLAN_PCP:
 706     case MFF_VLAN_PCP:
 707         mask->u8 = vlan_tci_to_pcp(wc->vlan_tci_mask);
 708         break;
 709
 710     case MFF_IPV4_SRC:
 711         mask->be32 = wc->nw_src_mask;
 712         break;
 713     case MFF_IPV4_DST:
 714         mask->be32 = wc->nw_dst_mask;
 715         break;
 716
 717     case MFF_IPV6_SRC:
 718         mask->ipv6 = wc->ipv6_src_mask;
 719         break;
 720     case MFF_IPV6_DST:
 721         mask->ipv6 = wc->ipv6_dst_mask;
 722         break;
 723     case MFF_IPV6_LABEL:
 724         mask->be32 = wc->ipv6_label_mask;
 725         break;
 726
 727     case MFF_IP_PROTO:
 728         mask->u8 = wc->nw_proto_mask;
 729         break;
 730     case MFF_IP_DSCP:
 731         mask->u8 = wc->nw_tos_mask & IP_DSCP_MASK;
 732         break;
 733     case MFF_IP_ECN:
 734         mask->u8 = wc->nw_tos_mask & IP_ECN_MASK;
 735         break;
 736
 737     case MFF_ND_TARGET:
 738         mask->ipv6 = wc->nd_target_mask;
 739         break;
 740
 741     case MFF_IP_TTL:
 742         mask->u8 = wc->nw_ttl_mask;
 743         break;
 744     case MFF_IP_FRAG:
 745         mask->u8 = wc->nw_frag_mask & FLOW_NW_FRAG_MASK;
 746         break;
 747
 748     case MFF_ARP_OP:
 749         mask->u8 = wc->nw_proto_mask;
 750         break;
 751     case MFF_ARP_SPA:
 752         mask->be32 = wc->nw_src_mask;
 753         break;
 754     case MFF_ARP_TPA:
 755         mask->be32 = wc->nw_dst_mask;
 756         break;
 757     case MFF_ARP_SHA:
 758     case MFF_ND_SLL:
 759         memcpy(mask->mac, wc->arp_sha_mask, ETH_ADDR_LEN);
 760         break;
 761     case MFF_ARP_THA:
 762     case MFF_ND_TLL:
 763         memcpy(mask->mac, wc->arp_tha_mask, ETH_ADDR_LEN);
 764         break;
 765
 766     case MFF_TCP_SRC:
 767     case MFF_UDP_SRC:
 768         mask->be16 = wc->tp_src_mask;
 769         break;
 770     case MFF_TCP_DST:
 771     case MFF_UDP_DST:
 772         mask->be16 = wc->tp_dst_mask;
 773         break;
 774
 775     case MFF_ICMPV4_TYPE:
 776     case MFF_ICMPV6_TYPE:
 777         mask->u8 = ntohs(wc->tp_src_mask);
 778         break;
 779     case MFF_ICMPV4_CODE:
 780     case MFF_ICMPV6_CODE:
 781         mask->u8 = ntohs(wc->tp_dst_mask);
 782         break;
 783
 784     case MFF_N_IDS:
 785     default:
 786         NOT_REACHED();
 787     }
 788 }
 789
 790 /* Tests whether 'mask' is a valid wildcard bit pattern for 'mf'.  Returns true
 791  * if the mask is valid, false otherwise. */
 792 bool
 793 mf_is_mask_valid(const struct mf_field *mf, const union mf_value *mask)
 794 {
 795     switch (mf->maskable) {
 796     case MFM_NONE:
 797         return (is_all_zeros((const uint8_t *) mask, mf->n_bytes) ||
 798                 is_all_ones((const uint8_t *) mask, mf->n_bytes));
 799
 800     case MFM_FULLY:
 801         return true;
 802     }
 803
 804     NOT_REACHED();
 805 }
 806
 807 static bool
 808 is_ip_any(const struct flow *flow)
 809 {
 810     return (flow->dl_type == htons(ETH_TYPE_IP) ||
 811             flow->dl_type == htons(ETH_TYPE_IPV6));
 812 }
 813
 814 static bool
 815 is_icmpv4(const struct flow *flow)
 816 {
 817     return (flow->dl_type == htons(ETH_TYPE_IP)
 818             && flow->nw_proto == IPPROTO_ICMP);
 819 }
 820
 821 static bool
 822 is_icmpv6(const struct flow *flow)
 823 {
 824     return (flow->dl_type == htons(ETH_TYPE_IPV6)
 825             && flow->nw_proto == IPPROTO_ICMPV6);
 826 }
 827
 828 /* Returns true if 'flow' meets the prerequisites for 'mf', false otherwise. */
 829 bool
 830 mf_are_prereqs_ok(const struct mf_field *mf, const struct flow *flow)
 831 {
 832     switch (mf->prereqs) {
 833     case MFP_NONE:
 834         return true;
 835
 836     case MFP_ARP:
 837         return flow->dl_type == htons(ETH_TYPE_ARP);
 838     case MFP_IPV4:
 839         return flow->dl_type == htons(ETH_TYPE_IP);
 840     case MFP_IPV6:
 841         return flow->dl_type == htons(ETH_TYPE_IPV6);
 842     case MFP_VLAN_VID:
 843         return (flow->vlan_tci & htons(VLAN_CFI)) != 0;
 844     case MFP_IP_ANY:
 845         return is_ip_any(flow);
 846
 847     case MFP_TCP:
 848         return is_ip_any(flow) && flow->nw_proto == IPPROTO_TCP;
 849     case MFP_UDP:
 850         return is_ip_any(flow) && flow->nw_proto == IPPROTO_UDP;
 851     case MFP_ICMPV4:
 852         return is_icmpv4(flow);
 853     case MFP_ICMPV6:
 854         return is_icmpv6(flow);
 855
 856     case MFP_ND:
 857         return (is_icmpv6(flow)
 858                 && flow->tp_dst == htons(0)
 859                 && (flow->tp_src == htons(ND_NEIGHBOR_SOLICIT) ||
 860                     flow->tp_src == htons(ND_NEIGHBOR_ADVERT)));
 861     case MFP_ND_SOLICIT:
 862         return (is_icmpv6(flow)
 863                 && flow->tp_dst == htons(0)
 864                 && (flow->tp_src == htons(ND_NEIGHBOR_SOLICIT)));
 865     case MFP_ND_ADVERT:
 866         return (is_icmpv6(flow)
 867                 && flow->tp_dst == htons(0)
 868                 && (flow->tp_src == htons(ND_NEIGHBOR_ADVERT)));
 869     }
 870
 871     NOT_REACHED();
 872 }
 873
 874 /* Returns true if 'value' may be a valid value *as part of a masked match*,
 875  * false otherwise.
 876  *
 877  * A value is not rejected just because it is not valid for the field in
 878  * question, but only if it doesn't make sense to test the bits in question at
 879  * all.  For example, the MFF_VLAN_TCI field will never have a nonzero value
 880  * without the VLAN_CFI bit being set, but we can't reject those values because
 881  * it is still legitimate to test just for those bits (see the documentation
 882  * for NXM_OF_VLAN_TCI in nicira-ext.h).  On the other hand, there is never a
 883  * reason to set the low bit of MFF_IP_DSCP to 1, so we reject that. */
 884 bool
 885 mf_is_value_valid(const struct mf_field *mf, const union mf_value *value)
 886 {
 887     switch (mf->id) {
 888     case MFF_TUN_ID:
 889     case MFF_METADATA:
 890     case MFF_IN_PORT:
 891     CASE_MFF_REGS:
 892     case MFF_ETH_SRC:
 893     case MFF_ETH_DST:
 894     case MFF_ETH_TYPE:
 895     case MFF_VLAN_TCI:
 896     case MFF_IPV4_SRC:
 897     case MFF_IPV4_DST:
 898     case MFF_IPV6_SRC:
 899     case MFF_IPV6_DST:
 900     case MFF_IP_PROTO:
 901     case MFF_IP_TTL:
 902     case MFF_ARP_SPA:
 903     case MFF_ARP_TPA:
 904     case MFF_ARP_SHA:
 905     case MFF_ARP_THA:
 906     case MFF_TCP_SRC:
 907     case MFF_TCP_DST:
 908     case MFF_UDP_SRC:
 909     case MFF_UDP_DST:
 910     case MFF_ICMPV4_TYPE:
 911     case MFF_ICMPV4_CODE:
 912     case MFF_ICMPV6_TYPE:
 913     case MFF_ICMPV6_CODE:
 914     case MFF_ND_TARGET:
 915     case MFF_ND_SLL:
 916     case MFF_ND_TLL:
 917         return true;
 918
 919     case MFF_IP_DSCP:
 920         return !(value->u8 & ~IP_DSCP_MASK);
 921     case MFF_IP_ECN:
 922         return !(value->u8 & ~IP_ECN_MASK);
 923     case MFF_IP_FRAG:
 924         return !(value->u8 & ~FLOW_NW_FRAG_MASK);
 925
 926     case MFF_ARP_OP:
 927         return !(value->be16 & htons(0xff00));
 928
 929     case MFF_DL_VLAN:
 930         return !(value->be16 & htons(VLAN_CFI | VLAN_PCP_MASK));
 931     case MFF_VLAN_VID:
 932         return !(value->be16 & htons(VLAN_PCP_MASK));
 933
 934     case MFF_DL_VLAN_PCP:
 935     case MFF_VLAN_PCP:
 936         return !(value->u8 & ~(VLAN_PCP_MASK >> VLAN_PCP_SHIFT));
 937
 938     case MFF_IPV6_LABEL:
 939         return !(value->be32 & ~htonl(IPV6_LABEL_MASK));
 940
 941     case MFF_N_IDS:
 942     default:
 943         NOT_REACHED();
 944     }
 945 }
 946
 947 /* Copies the value of field 'mf' from 'flow' into 'value'.  The caller is
 948  * responsible for ensuring that 'flow' meets 'mf''s prerequisites. */
 949 void
 950 mf_get_value(const struct mf_field *mf, const struct flow *flow,
 951              union mf_value *value)
 952 {
 953     switch (mf->id) {
 954     case MFF_TUN_ID:
 955         value->be64 = flow->tun_id;
 956         break;
 957     case MFF_METADATA:
 958         value->be64 = flow->metadata;
 959         break;
 960
 961     case MFF_IN_PORT:
 962         value->be16 = htons(flow->in_port);
 963         break;
 964
 965     CASE_MFF_REGS:
 966         value->be32 = htonl(flow->regs[mf->id - MFF_REG0]);
 967         break;
 968
 969     case MFF_ETH_SRC:
 970         memcpy(value->mac, flow->dl_src, ETH_ADDR_LEN);
 971         break;
 972
 973     case MFF_ETH_DST:
 974         memcpy(value->mac, flow->dl_dst, ETH_ADDR_LEN);
 975         break;
 976
 977     case MFF_ETH_TYPE:
 978         value->be16 = flow->dl_type;
 979         break;
 980
 981     case MFF_VLAN_TCI:
 982         value->be16 = flow->vlan_tci;
 983         break;
 984
 985     case MFF_DL_VLAN:
 986         value->be16 = flow->vlan_tci & htons(VLAN_VID_MASK);
 987         break;
 988     case MFF_VLAN_VID:
 989         value->be16 = flow->vlan_tci & htons(VLAN_VID_MASK | VLAN_CFI);
 990         break;
 991
 992     case MFF_DL_VLAN_PCP:
 993     case MFF_VLAN_PCP:
 994         value->u8 = vlan_tci_to_pcp(flow->vlan_tci);
 995         break;
 996
 997     case MFF_IPV4_SRC:
 998         value->be32 = flow->nw_src;
 999         break;
1000
1001     case MFF_IPV4_DST:
1002         value->be32 = flow->nw_dst;
1003         break;
1004
1005     case MFF_IPV6_SRC:
1006         value->ipv6 = flow->ipv6_src;
1007         break;
1008
1009     case MFF_IPV6_DST:
1010         value->ipv6 = flow->ipv6_dst;
1011         break;
1012
1013     case MFF_IPV6_LABEL:
1014         value->be32 = flow->ipv6_label;
1015         break;
1016
1017     case MFF_IP_PROTO:
1018         value->u8 = flow->nw_proto;
1019         break;
1020
1021     case MFF_IP_DSCP:
1022         value->u8 = flow->nw_tos & IP_DSCP_MASK;
1023         break;
1024
1025     case MFF_IP_ECN:
1026         value->u8 = flow->nw_tos & IP_ECN_MASK;
1027         break;
1028
1029     case MFF_IP_TTL:
1030         value->u8 = flow->nw_ttl;
1031         break;
1032
1033     case MFF_IP_FRAG:
1034         value->u8 = flow->nw_frag;
1035         break;
1036
1037     case MFF_ARP_OP:
1038         value->be16 = htons(flow->nw_proto);
1039         break;
1040
1041     case MFF_ARP_SPA:
1042         value->be32 = flow->nw_src;
1043         break;
1044
1045     case MFF_ARP_TPA:
1046         value->be32 = flow->nw_dst;
1047         break;
1048
1049     case MFF_ARP_SHA:
1050     case MFF_ND_SLL:
1051         memcpy(value->mac, flow->arp_sha, ETH_ADDR_LEN);
1052         break;
1053
1054     case MFF_ARP_THA:
1055     case MFF_ND_TLL:
1056         memcpy(value->mac, flow->arp_tha, ETH_ADDR_LEN);
1057         break;
1058
1059     case MFF_TCP_SRC:
1060     case MFF_UDP_SRC:
1061         value->be16 = flow->tp_src;
1062         break;
1063
1064     case MFF_TCP_DST:
1065     case MFF_UDP_DST:
1066         value->be16 = flow->tp_dst;
1067         break;
1068
1069     case MFF_ICMPV4_TYPE:
1070     case MFF_ICMPV6_TYPE:
1071         value->u8 = ntohs(flow->tp_src);
1072         break;
1073
1074     case MFF_ICMPV4_CODE:
1075     case MFF_ICMPV6_CODE:
1076         value->u8 = ntohs(flow->tp_dst);
1077         break;
1078
1079     case MFF_ND_TARGET:
1080         value->ipv6 = flow->nd_target;
1081         break;
1082
1083     case MFF_N_IDS:
1084     default:
1085         NOT_REACHED();
1086     }
1087 }
1088
1089 /* Makes 'rule' match field 'mf' exactly, with the value matched taken from
1090  * 'value'.  The caller is responsible for ensuring that 'rule' meets 'mf''s
1091  * prerequisites. */
1092 void
1093 mf_set_value(const struct mf_field *mf,
1094              const union mf_value *value, struct cls_rule *rule)
1095 {
1096     switch (mf->id) {
1097     case MFF_TUN_ID:
1098         cls_rule_set_tun_id(rule, value->be64);
1099         break;
1100     case MFF_METADATA:
1101         cls_rule_set_metadata(rule, value->be64);
1102         break;
1103
1104     case MFF_IN_PORT:
1105         cls_rule_set_in_port(rule, ntohs(value->be16));
1106         break;
1107
1108     CASE_MFF_REGS:
1109         cls_rule_set_reg(rule, mf->id - MFF_REG0, ntohl(value->be32));
1110         break;
1111
1112     case MFF_ETH_SRC:
1113         cls_rule_set_dl_src(rule, value->mac);
1114         break;
1115
1116     case MFF_ETH_DST:
1117         cls_rule_set_dl_dst(rule, value->mac);
1118         break;
1119
1120     case MFF_ETH_TYPE:
1121         cls_rule_set_dl_type(rule, value->be16);
1122         break;
1123
1124     case MFF_VLAN_TCI:
1125         cls_rule_set_dl_tci(rule, value->be16);
1126         break;
1127
1128     case MFF_DL_VLAN:
1129         cls_rule_set_dl_vlan(rule, value->be16);
1130         break;
1131     case MFF_VLAN_VID:
1132         cls_rule_set_vlan_vid(rule, value->be16);
1133         break;
1134
1135     case MFF_DL_VLAN_PCP:
1136     case MFF_VLAN_PCP:
1137         cls_rule_set_dl_vlan_pcp(rule, value->u8);
1138         break;
1139
1140     case MFF_IPV4_SRC:
1141         cls_rule_set_nw_src(rule, value->be32);
1142         break;
1143
1144     case MFF_IPV4_DST:
1145         cls_rule_set_nw_dst(rule, value->be32);
1146         break;
1147
1148     case MFF_IPV6_SRC:
1149         cls_rule_set_ipv6_src(rule, &value->ipv6);
1150         break;
1151
1152     case MFF_IPV6_DST:
1153         cls_rule_set_ipv6_dst(rule, &value->ipv6);
1154         break;
1155
1156     case MFF_IPV6_LABEL:
1157         cls_rule_set_ipv6_label(rule, value->be32);
1158         break;
1159
1160     case MFF_IP_PROTO:
1161         cls_rule_set_nw_proto(rule, value->u8);
1162         break;
1163
1164     case MFF_IP_DSCP:
1165         cls_rule_set_nw_dscp(rule, value->u8);
1166         break;
1167
1168     case MFF_IP_ECN:
1169         cls_rule_set_nw_ecn(rule, value->u8);
1170         break;
1171
1172     case MFF_IP_TTL:
1173         cls_rule_set_nw_ttl(rule, value->u8);
1174         break;
1175
1176     case MFF_IP_FRAG:
1177         cls_rule_set_nw_frag(rule, value->u8);
1178         break;
1179
1180     case MFF_ARP_OP:
1181         cls_rule_set_nw_proto(rule, ntohs(value->be16));
1182         break;
1183
1184     case MFF_ARP_SPA:
1185         cls_rule_set_nw_src(rule, value->be32);
1186         break;
1187
1188     case MFF_ARP_TPA:
1189         cls_rule_set_nw_dst(rule, value->be32);
1190         break;
1191
1192     case MFF_ARP_SHA:
1193     case MFF_ND_SLL:
1194         cls_rule_set_arp_sha(rule, value->mac);
1195         break;
1196
1197     case MFF_ARP_THA:
1198     case MFF_ND_TLL:
1199         cls_rule_set_arp_tha(rule, value->mac);
1200         break;
1201
1202     case MFF_TCP_SRC:
1203     case MFF_UDP_SRC:
1204         cls_rule_set_tp_src(rule, value->be16);
1205         break;
1206
1207     case MFF_TCP_DST:
1208     case MFF_UDP_DST:
1209         cls_rule_set_tp_dst(rule, value->be16);
1210         break;
1211
1212     case MFF_ICMPV4_TYPE:
1213     case MFF_ICMPV6_TYPE:
1214         cls_rule_set_icmp_type(rule, value->u8);
1215         break;
1216
1217     case MFF_ICMPV4_CODE:
1218     case MFF_ICMPV6_CODE:
1219         cls_rule_set_icmp_code(rule, value->u8);
1220         break;
1221
1222     case MFF_ND_TARGET:
1223         cls_rule_set_nd_target(rule, &value->ipv6);
1224         break;
1225
1226     case MFF_N_IDS:
1227     default:
1228         NOT_REACHED();
1229     }
1230 }
1231
1232 /* Makes 'rule' match field 'mf' exactly, with the value matched taken from
1233  * 'value'.  The caller is responsible for ensuring that 'rule' meets 'mf''s
1234  * prerequisites. */
1235 void
1236 mf_set_flow_value(const struct mf_field *mf,
1237                   const union mf_value *value, struct flow *flow)
1238 {
1239     switch (mf->id) {
1240     case MFF_TUN_ID:
1241         flow->tun_id = value->be64;
1242         break;
1243     case MFF_METADATA:
1244         flow->metadata = value->be64;
1245         break;
1246
1247     case MFF_IN_PORT:
1248         flow->in_port = ntohs(value->be16);
1249         break;
1250
1251     CASE_MFF_REGS:
1252         flow->regs[mf->id - MFF_REG0] = ntohl(value->be32);
1253         break;
1254
1255     case MFF_ETH_SRC:
1256         memcpy(flow->dl_src, value->mac, ETH_ADDR_LEN);
1257         break;
1258
1259     case MFF_ETH_DST:
1260         memcpy(flow->dl_dst, value->mac, ETH_ADDR_LEN);
1261         break;
1262
1263     case MFF_ETH_TYPE:
1264         flow->dl_type = value->be16;
1265         break;
1266
1267     case MFF_VLAN_TCI:
1268         flow->vlan_tci = value->be16;
1269         break;
1270
1271     case MFF_DL_VLAN:
1272         flow_set_dl_vlan(flow, value->be16);
1273         break;
1274     case MFF_VLAN_VID:
1275         flow_set_vlan_vid(flow, value->be16);
1276         break;
1277
1278     case MFF_DL_VLAN_PCP:
1279     case MFF_VLAN_PCP:
1280         flow_set_vlan_pcp(flow, value->u8);
1281         break;
1282
1283     case MFF_IPV4_SRC:
1284         flow->nw_src = value->be32;
1285         break;
1286
1287     case MFF_IPV4_DST:
1288         flow->nw_dst = value->be32;
1289         break;
1290
1291     case MFF_IPV6_SRC:
1292         flow->ipv6_src = value->ipv6;
1293         break;
1294
1295     case MFF_IPV6_DST:
1296         flow->ipv6_dst = value->ipv6;
1297         break;
1298
1299     case MFF_IPV6_LABEL:
1300         flow->ipv6_label = value->be32 & ~htonl(IPV6_LABEL_MASK);
1301         break;
1302
1303     case MFF_IP_PROTO:
1304         flow->nw_proto = value->u8;
1305         break;
1306
1307     case MFF_IP_DSCP:
1308         flow->nw_tos &= ~IP_DSCP_MASK;
1309         flow->nw_tos |= value->u8 & IP_DSCP_MASK;
1310         break;
1311
1312     case MFF_IP_ECN:
1313         flow->nw_tos &= ~IP_ECN_MASK;
1314         flow->nw_tos |= value->u8 & IP_ECN_MASK;
1315         break;
1316
1317     case MFF_IP_TTL:
1318         flow->nw_ttl = value->u8;
1319         break;
1320
1321     case MFF_IP_FRAG:
1322         flow->nw_frag &= value->u8;
1323         break;
1324
1325     case MFF_ARP_OP:
1326         flow->nw_proto = ntohs(value->be16);
1327         break;
1328
1329     case MFF_ARP_SPA:
1330         flow->nw_src = value->be32;
1331         break;
1332
1333     case MFF_ARP_TPA:
1334         flow->nw_dst = value->be32;
1335         break;
1336
1337     case MFF_ARP_SHA:
1338     case MFF_ND_SLL:
1339         memcpy(flow->arp_sha, value->mac, ETH_ADDR_LEN);
1340         break;
1341
1342     case MFF_ARP_THA:
1343     case MFF_ND_TLL:
1344         memcpy(flow->arp_tha, value->mac, ETH_ADDR_LEN);
1345         break;
1346
1347     case MFF_TCP_SRC:
1348     case MFF_UDP_SRC:
1349         flow->tp_src = value->be16;
1350         break;
1351
1352     case MFF_TCP_DST:
1353     case MFF_UDP_DST:
1354         flow->tp_dst = value->be16;
1355         break;
1356
1357     case MFF_ICMPV4_TYPE:
1358     case MFF_ICMPV6_TYPE:
1359         flow->tp_src = htons(value->u8);
1360         break;
1361
1362     case MFF_ICMPV4_CODE:
1363     case MFF_ICMPV6_CODE:
1364         flow->tp_dst = htons(value->u8);
1365         break;
1366
1367     case MFF_ND_TARGET:
1368         flow->nd_target = value->ipv6;
1369         break;
1370
1371     case MFF_N_IDS:
1372     default:
1373         NOT_REACHED();
1374     }
1375 }
1376
1377 /* Returns true if 'mf' has a zero value in 'flow', false if it is nonzero.
1378  *
1379  * The caller is responsible for ensuring that 'flow' meets 'mf''s
1380  * prerequisites. */
1381 bool
1382 mf_is_zero(const struct mf_field *mf, const struct flow *flow)
1383 {
1384     union mf_value value;
1385
1386     mf_get_value(mf, flow, &value);
1387     return is_all_zeros((const uint8_t *) &value, mf->n_bytes);
1388 }
1389
1390 /* Makes 'rule' wildcard field 'mf'.
1391  *
1392  * The caller is responsible for ensuring that 'rule' meets 'mf''s
1393  * prerequisites. */
1394 void
1395 mf_set_wild(const struct mf_field *mf, struct cls_rule *rule)
1396 {
1397     switch (mf->id) {
1398     case MFF_TUN_ID:
1399         cls_rule_set_tun_id_masked(rule, htonll(0), htonll(0));
1400         break;
1401     case MFF_METADATA:
1402         cls_rule_set_metadata_masked(rule, htonll(0), htonll(0));
1403
1404     case MFF_IN_PORT:
1405         rule->flow.in_port = 0;
1406         rule->wc.in_port_mask = 0;
1407         break;
1408
1409     CASE_MFF_REGS:
1410         cls_rule_set_reg_masked(rule, mf->id - MFF_REG0, 0, 0);
1411         break;
1412
1413     case MFF_ETH_SRC:
1414         memset(rule->flow.dl_src, 0, ETH_ADDR_LEN);
1415         memset(rule->wc.dl_src_mask, 0, ETH_ADDR_LEN);
1416         break;
1417
1418     case MFF_ETH_DST:
1419         memset(rule->flow.dl_dst, 0, ETH_ADDR_LEN);
1420         memset(rule->wc.dl_dst_mask, 0, ETH_ADDR_LEN);
1421         break;
1422
1423     case MFF_ETH_TYPE:
1424         rule->flow.dl_type = htons(0);
1425         rule->wc.dl_type_mask = htons(0);
1426         break;
1427
1428     case MFF_VLAN_TCI:
1429         cls_rule_set_dl_tci_masked(rule, htons(0), htons(0));
1430         break;
1431
1432     case MFF_DL_VLAN:
1433     case MFF_VLAN_VID:
1434         cls_rule_set_any_vid(rule);
1435         break;
1436
1437     case MFF_DL_VLAN_PCP:
1438     case MFF_VLAN_PCP:
1439         cls_rule_set_any_pcp(rule);
1440         break;
1441
1442     case MFF_IPV4_SRC:
1443     case MFF_ARP_SPA:
1444         cls_rule_set_nw_src_masked(rule, htonl(0), htonl(0));
1445         break;
1446
1447     case MFF_IPV4_DST:
1448     case MFF_ARP_TPA:
1449         cls_rule_set_nw_dst_masked(rule, htonl(0), htonl(0));
1450         break;
1451
1452     case MFF_IPV6_SRC:
1453         memset(&rule->wc.ipv6_src_mask, 0, sizeof rule->wc.ipv6_src_mask);
1454         memset(&rule->flow.ipv6_src, 0, sizeof rule->flow.ipv6_src);
1455         break;
1456
1457     case MFF_IPV6_DST:
1458         memset(&rule->wc.ipv6_dst_mask, 0, sizeof rule->wc.ipv6_dst_mask);
1459         memset(&rule->flow.ipv6_dst, 0, sizeof rule->flow.ipv6_dst);
1460         break;
1461
1462     case MFF_IPV6_LABEL:
1463         rule->wc.ipv6_label_mask = 0;
1464         rule->flow.ipv6_label = 0;
1465         break;
1466
1467     case MFF_IP_PROTO:
1468         rule->wc.nw_proto_mask = 0;
1469         rule->flow.nw_proto = 0;
1470         break;
1471
1472     case MFF_IP_DSCP:
1473         rule->wc.nw_tos_mask &= ~IP_DSCP_MASK;
1474         rule->flow.nw_tos &= ~IP_DSCP_MASK;
1475         break;
1476
1477     case MFF_IP_ECN:
1478         rule->wc.nw_tos_mask &= ~IP_ECN_MASK;
1479         rule->flow.nw_tos &= ~IP_ECN_MASK;
1480         break;
1481
1482     case MFF_IP_TTL:
1483         rule->wc.nw_ttl_mask = 0;
1484         rule->flow.nw_ttl = 0;
1485         break;
1486
1487     case MFF_IP_FRAG:
1488         rule->wc.nw_frag_mask |= FLOW_NW_FRAG_MASK;
1489         rule->flow.nw_frag &= ~FLOW_NW_FRAG_MASK;
1490         break;
1491
1492     case MFF_ARP_OP:
1493         rule->wc.nw_proto_mask = 0;
1494         rule->flow.nw_proto = 0;
1495         break;
1496
1497     case MFF_ARP_SHA:
1498     case MFF_ND_SLL:
1499         memset(rule->flow.arp_sha, 0, ETH_ADDR_LEN);
1500         memset(rule->wc.arp_sha_mask, 0, ETH_ADDR_LEN);
1501         break;
1502
1503     case MFF_ARP_THA:
1504     case MFF_ND_TLL:
1505         memset(rule->flow.arp_tha, 0, ETH_ADDR_LEN);
1506         memset(rule->wc.arp_tha_mask, 0, ETH_ADDR_LEN);
1507         break;
1508
1509     case MFF_TCP_SRC:
1510     case MFF_UDP_SRC:
1511     case MFF_ICMPV4_TYPE:
1512     case MFF_ICMPV6_TYPE:
1513         rule->wc.tp_src_mask = htons(0);
1514         rule->flow.tp_src = htons(0);
1515         break;
1516
1517     case MFF_TCP_DST:
1518     case MFF_UDP_DST:
1519     case MFF_ICMPV4_CODE:
1520     case MFF_ICMPV6_CODE:
1521         rule->wc.tp_dst_mask = htons(0);
1522         rule->flow.tp_dst = htons(0);
1523         break;
1524
1525     case MFF_ND_TARGET:
1526         memset(&rule->wc.nd_target_mask, 0, sizeof rule->wc.nd_target_mask);
1527         memset(&rule->flow.nd_target, 0, sizeof rule->flow.nd_target);
1528         break;
1529
1530     case MFF_N_IDS:
1531     default:
1532         NOT_REACHED();
1533     }
1534 }
1535
1536 /* Makes 'rule' match field 'mf' with the specified 'value' and 'mask'.
1537  * 'value' specifies a value to match and 'mask' specifies a wildcard pattern,
1538  * with a 1-bit indicating that the corresponding value bit must match and a
1539  * 0-bit indicating a don't-care.
1540  *
1541  * If 'mask' is NULL or points to all-1-bits, then this call is equivalent to
1542  * mf_set_value(mf, value, rule).  If 'mask' points to all-0-bits, then this
1543  * call is equivalent to mf_set_wild(mf, rule).
1544  *
1545  * 'mask' must be a valid mask for 'mf' (see mf_is_mask_valid()).  The caller
1546  * is responsible for ensuring that 'rule' meets 'mf''s prerequisites. */
1547 void
1548 mf_set(const struct mf_field *mf,
1549        const union mf_value *value, const union mf_value *mask,
1550        struct cls_rule *rule)
1551 {
1552     if (!mask || is_all_ones((const uint8_t *) mask, mf->n_bytes)) {
1553         mf_set_value(mf, value, rule);
1554         return;
1555     } else if (is_all_zeros((const uint8_t *) mask, mf->n_bytes)) {
1556         mf_set_wild(mf, rule);
1557         return;
1558     }
1559
1560     switch (mf->id) {
1561     case MFF_IN_PORT:
1562     case MFF_ETH_TYPE:
1563     case MFF_DL_VLAN:
1564     case MFF_DL_VLAN_PCP:
1565     case MFF_VLAN_PCP:
1566     case MFF_IP_PROTO:
1567     case MFF_IP_TTL:
1568     case MFF_IP_DSCP:
1569     case MFF_IP_ECN:
1570     case MFF_ARP_OP:
1571     case MFF_ICMPV4_TYPE:
1572     case MFF_ICMPV4_CODE:
1573     case MFF_ICMPV6_TYPE:
1574     case MFF_ICMPV6_CODE:
1575         NOT_REACHED();
1576
1577     case MFF_TUN_ID:
1578         cls_rule_set_tun_id_masked(rule, value->be64, mask->be64);
1579         break;
1580     case MFF_METADATA:
1581         cls_rule_set_metadata_masked(rule, value->be64, mask->be64);
1582         break;
1583
1584     CASE_MFF_REGS:
1585         cls_rule_set_reg_masked(rule, mf->id - MFF_REG0,
1586                                 ntohl(value->be32), ntohl(mask->be32));
1587         break;
1588
1589     case MFF_ETH_DST:
1590         cls_rule_set_dl_dst_masked(rule, value->mac, mask->mac);
1591         break;
1592
1593     case MFF_ETH_SRC:
1594         cls_rule_set_dl_src_masked(rule, value->mac, mask->mac);
1595         break;
1596
1597     case MFF_ARP_SHA:
1598     case MFF_ND_SLL:
1599         cls_rule_set_arp_sha_masked(rule, value->mac, mask->mac);
1600         break;
1601
1602     case MFF_ARP_THA:
1603     case MFF_ND_TLL:
1604         cls_rule_set_arp_tha_masked(rule, value->mac, mask->mac);
1605         break;
1606
1607     case MFF_VLAN_TCI:
1608         cls_rule_set_dl_tci_masked(rule, value->be16, mask->be16);
1609         break;
1610
1611     case MFF_VLAN_VID:
1612         cls_rule_set_vlan_vid_masked(rule, value->be16, mask->be16);
1613         break;
1614
1615     case MFF_IPV4_SRC:
1616         cls_rule_set_nw_src_masked(rule, value->be32, mask->be32);
1617         break;
1618
1619     case MFF_IPV4_DST:
1620         cls_rule_set_nw_dst_masked(rule, value->be32, mask->be32);
1621         break;
1622
1623     case MFF_IPV6_SRC:
1624         cls_rule_set_ipv6_src_masked(rule, &value->ipv6, &mask->ipv6);
1625         break;
1626
1627     case MFF_IPV6_DST:
1628         cls_rule_set_ipv6_dst_masked(rule, &value->ipv6, &mask->ipv6);
1629         break;
1630
1631     case MFF_IPV6_LABEL:
1632         if ((mask->be32 & htonl(IPV6_LABEL_MASK)) == htonl(IPV6_LABEL_MASK)) {
1633             mf_set_value(mf, value, rule);
1634         } else {
1635             cls_rule_set_ipv6_label_masked(rule, value->be32, mask->be32);
1636         }
1637         break;
1638
1639     case MFF_ND_TARGET:
1640         cls_rule_set_nd_target_masked(rule, &value->ipv6, &mask->ipv6);
1641         break;
1642
1643     case MFF_IP_FRAG:
1644         cls_rule_set_nw_frag_masked(rule, value->u8, mask->u8);
1645         break;
1646
1647     case MFF_ARP_SPA:
1648         cls_rule_set_nw_src_masked(rule, value->be32, mask->be32);
1649         break;
1650
1651     case MFF_ARP_TPA:
1652         cls_rule_set_nw_dst_masked(rule, value->be32, mask->be32);
1653         break;
1654
1655     case MFF_TCP_SRC:
1656     case MFF_UDP_SRC:
1657         cls_rule_set_tp_src_masked(rule, value->be16, mask->be16);
1658         break;
1659
1660     case MFF_TCP_DST:
1661     case MFF_UDP_DST:
1662         cls_rule_set_tp_dst_masked(rule, value->be16, mask->be16);
1663         break;
1664
1665     case MFF_N_IDS:
1666     default:
1667         NOT_REACHED();
1668     }
1669 }
1670
1671 static enum ofperr
1672 mf_check__(const struct mf_subfield *sf, const struct flow *flow,
1673            const char *type)
1674 {
1675     if (!sf->field) {
1676         VLOG_WARN_RL(&rl, "unknown %s field", type);
1677     } else if (!sf->n_bits) {
1678         VLOG_WARN_RL(&rl, "zero bit %s field %s", type, sf->field->name);
1679     } else if (sf->ofs >= sf->field->n_bits) {
1680         VLOG_WARN_RL(&rl, "bit offset %d exceeds %d-bit width of %s field %s",
1681                      sf->ofs, sf->field->n_bits, type, sf->field->name);
1682     } else if (sf->ofs + sf->n_bits > sf->field->n_bits) {
1683         VLOG_WARN_RL(&rl, "bit offset %d and width %d exceeds %d-bit width "
1684                      "of %s field %s", sf->ofs, sf->n_bits,
1685                      sf->field->n_bits, type, sf->field->name);
1686     } else if (flow && !mf_are_prereqs_ok(sf->field, flow)) {
1687         VLOG_WARN_RL(&rl, "%s field %s lacks correct prerequisites",
1688                      type, sf->field->name);
1689     } else {
1690         return 0;
1691     }
1692
1693     return OFPERR_OFPBAC_BAD_ARGUMENT;
1694 }
1695
1696 /* Checks whether 'sf' is valid for reading a subfield out of 'flow'.  Returns
1697  * 0 if so, otherwise an OpenFlow error code (e.g. as returned by
1698  * ofp_mkerr()).  */
1699 enum ofperr
1700 mf_check_src(const struct mf_subfield *sf, const struct flow *flow)
1701 {
1702     return mf_check__(sf, flow, "source");
1703 }
1704
1705 /* Checks whether 'sf' is valid for writing a subfield into 'flow'.  Returns 0
1706  * if so, otherwise an OpenFlow error code (e.g. as returned by
1707  * ofp_mkerr()). */
1708 enum ofperr
1709 mf_check_dst(const struct mf_subfield *sf, const struct flow *flow)
1710 {
1711     int error = mf_check__(sf, flow, "destination");
1712     if (!error && !sf->field->writable) {
1713         VLOG_WARN_RL(&rl, "destination field %s is not writable",
1714                      sf->field->name);
1715         return OFPERR_OFPBAC_BAD_ARGUMENT;
1716     }
1717     return error;
1718 }
1719
1720 /* Copies the value and wildcard bit pattern for 'mf' from 'rule' into the
1721  * 'value' and 'mask', respectively. */
1722 void
1723 mf_get(const struct mf_field *mf, const struct cls_rule *rule,
1724        union mf_value *value, union mf_value *mask)
1725 {
1726     mf_get_value(mf, &rule->flow, value);
1727     mf_get_mask(mf, &rule->wc, mask);
1728 }
1729
1730 /* Assigns a random value for field 'mf' to 'value'. */
1731 void
1732 mf_random_value(const struct mf_field *mf, union mf_value *value)
1733 {
1734     random_bytes(value, mf->n_bytes);
1735
1736     switch (mf->id) {
1737     case MFF_TUN_ID:
1738     case MFF_METADATA:
1739     case MFF_IN_PORT:
1740     CASE_MFF_REGS:
1741     case MFF_ETH_SRC:
1742     case MFF_ETH_DST:
1743     case MFF_ETH_TYPE:
1744     case MFF_VLAN_TCI:
1745     case MFF_IPV4_SRC:
1746     case MFF_IPV4_DST:
1747     case MFF_IPV6_SRC:
1748     case MFF_IPV6_DST:
1749     case MFF_IP_PROTO:
1750     case MFF_IP_TTL:
1751     case MFF_ARP_SPA:
1752     case MFF_ARP_TPA:
1753     case MFF_ARP_SHA:
1754     case MFF_ARP_THA:
1755     case MFF_TCP_SRC:
1756     case MFF_TCP_DST:
1757     case MFF_UDP_SRC:
1758     case MFF_UDP_DST:
1759     case MFF_ICMPV4_TYPE:
1760     case MFF_ICMPV4_CODE:
1761     case MFF_ICMPV6_TYPE:
1762     case MFF_ICMPV6_CODE:
1763     case MFF_ND_TARGET:
1764     case MFF_ND_SLL:
1765     case MFF_ND_TLL:
1766         break;
1767
1768     case MFF_IPV6_LABEL:
1769         value->be32 &= ~htonl(IPV6_LABEL_MASK);
1770         break;
1771
1772     case MFF_IP_DSCP:
1773         value->u8 &= IP_DSCP_MASK;
1774         break;
1775
1776     case MFF_IP_ECN:
1777         value->u8 &= IP_ECN_MASK;
1778         break;
1779
1780     case MFF_IP_FRAG:
1781         value->u8 &= FLOW_NW_FRAG_MASK;
1782         break;
1783
1784     case MFF_ARP_OP:
1785         value->be16 &= htons(0xff);
1786         break;
1787
1788     case MFF_DL_VLAN:
1789         value->be16 &= htons(VLAN_VID_MASK);
1790         break;
1791     case MFF_VLAN_VID:
1792         value->be16 &= htons(VLAN_VID_MASK | VLAN_CFI);
1793         break;
1794
1795     case MFF_DL_VLAN_PCP:
1796     case MFF_VLAN_PCP:
1797         value->u8 &= 0x07;
1798         break;
1799
1800     case MFF_N_IDS:
1801     default:
1802         NOT_REACHED();
1803     }
1804 }
1805
1806 static char *
1807 mf_from_integer_string(const struct mf_field *mf, const char *s,
1808                        uint8_t *valuep, uint8_t *maskp)
1809 {
1810     unsigned long long int integer, mask;
1811     char *tail;
1812     int i;
1813
1814     errno = 0;
1815     integer = strtoull(s, &tail, 0);
1816     if (errno || (*tail != '\0' && *tail != '/')) {
1817         goto syntax_error;
1818     }
1819
1820     if (*tail == '/') {
1821         mask = strtoull(tail + 1, &tail, 0);
1822         if (errno || *tail != '\0') {
1823             goto syntax_error;
1824         }
1825     } else {
1826         mask = ULLONG_MAX;
1827     }
1828
1829     for (i = mf->n_bytes - 1; i >= 0; i--) {
1830         valuep[i] = integer;
1831         maskp[i] = mask;
1832         integer >>= 8;
1833         mask >>= 8;
1834     }
1835     if (integer) {
1836         return xasprintf("%s: value too large for %u-byte field %s",
1837                          s, mf->n_bytes, mf->name);
1838     }
1839     return NULL;
1840
1841 syntax_error:
1842     return xasprintf("%s: bad syntax for %s", s, mf->name);
1843 }
1844
1845 static char *
1846 mf_from_ethernet_string(const struct mf_field *mf, const char *s,
1847                         uint8_t mac[ETH_ADDR_LEN],
1848                         uint8_t mask[ETH_ADDR_LEN])
1849 {
1850     assert(mf->n_bytes == ETH_ADDR_LEN);
1851
1852     switch (sscanf(s, ETH_ADDR_SCAN_FMT"/"ETH_ADDR_SCAN_FMT,
1853                    ETH_ADDR_SCAN_ARGS(mac), ETH_ADDR_SCAN_ARGS(mask))){
1854     case ETH_ADDR_SCAN_COUNT * 2:
1855         return NULL;
1856
1857     case ETH_ADDR_SCAN_COUNT:
1858         memset(mask, 0xff, ETH_ADDR_LEN);
1859         return NULL;
1860
1861     default:
1862         return xasprintf("%s: invalid Ethernet address", s);
1863     }
1864 }
1865
1866 static char *
1867 mf_from_ipv4_string(const struct mf_field *mf, const char *s,
1868                     ovs_be32 *ip, ovs_be32 *mask)
1869 {
1870     int prefix;
1871
1872     assert(mf->n_bytes == sizeof *ip);
1873
1874     if (sscanf(s, IP_SCAN_FMT"/"IP_SCAN_FMT,
1875                IP_SCAN_ARGS(ip), IP_SCAN_ARGS(mask)) == IP_SCAN_COUNT * 2) {
1876         /* OK. */
1877     } else if (sscanf(s, IP_SCAN_FMT"/%d",
1878                       IP_SCAN_ARGS(ip), &prefix) == IP_SCAN_COUNT + 1) {
1879         if (prefix <= 0 || prefix > 32) {
1880             return xasprintf("%s: network prefix bits not between 1 and "
1881                              "32", s);
1882         } else if (prefix == 32) {
1883             *mask = htonl(UINT32_MAX);
1884         } else {
1885             *mask = htonl(((1u << prefix) - 1) << (32 - prefix));
1886         }
1887     } else if (sscanf(s, IP_SCAN_FMT, IP_SCAN_ARGS(ip)) == IP_SCAN_COUNT) {
1888         *mask = htonl(UINT32_MAX);
1889     } else {
1890         return xasprintf("%s: invalid IP address", s);
1891     }
1892     return NULL;
1893 }
1894
1895 static char *
1896 mf_from_ipv6_string(const struct mf_field *mf, const char *s,
1897                     struct in6_addr *value, struct in6_addr *mask)
1898 {
1899     char *str = xstrdup(s);
1900     char *save_ptr = NULL;
1901     const char *name, *netmask;
1902     int retval;
1903
1904     assert(mf->n_bytes == sizeof *value);
1905
1906     name = strtok_r(str, "/", &save_ptr);
1907     retval = name ? lookup_ipv6(name, value) : EINVAL;
1908     if (retval) {
1909         char *err;
1910
1911         err = xasprintf("%s: could not convert to IPv6 address", str);
1912         free(str);
1913
1914         return err;
1915     }
1916
1917     netmask = strtok_r(NULL, "/", &save_ptr);
1918     if (netmask) {
1919         if (inet_pton(AF_INET6, netmask, mask) != 1) {
1920             int prefix = atoi(netmask);
1921             if (prefix <= 0 || prefix > 128) {
1922                 free(str);
1923                 return xasprintf("%s: prefix bits not between 1 and 128", s);
1924             } else {
1925                 *mask = ipv6_create_mask(prefix);
1926             }
1927         }
1928     } else {
1929         *mask = in6addr_exact;
1930     }
1931     free(str);
1932
1933     return NULL;
1934 }
1935
1936 static char *
1937 mf_from_ofp_port_string(const struct mf_field *mf, const char *s,
1938                         ovs_be16 *valuep, ovs_be16 *maskp)
1939 {
1940     uint16_t port;
1941
1942     assert(mf->n_bytes == sizeof(ovs_be16));
1943     if (ofputil_port_from_string(s, &port)) {
1944         *valuep = htons(port);
1945         *maskp = htons(UINT16_MAX);
1946         return NULL;
1947     } else {
1948         return mf_from_integer_string(mf, s,
1949                                       (uint8_t *) valuep, (uint8_t *) maskp);
1950     }
1951 }
1952
1953 struct frag_handling {
1954     const char *name;
1955     uint8_t mask;
1956     uint8_t value;
1957 };
1958
1959 static const struct frag_handling all_frags[] = {
1960 #define A FLOW_NW_FRAG_ANY
1961 #define L FLOW_NW_FRAG_LATER
1962     /* name               mask  value */
1963
1964     { "no",               A|L,  0     },
1965     { "first",            A|L,  A     },
1966     { "later",            A|L,  A|L   },
1967
1968     { "no",               A,    0     },
1969     { "yes",              A,    A     },
1970
1971     { "not_later",        L,    0     },
1972     { "later",            L,    L     },
1973 #undef A
1974 #undef L
1975 };
1976
1977 static char *
1978 mf_from_frag_string(const char *s, uint8_t *valuep, uint8_t *maskp)
1979 {
1980     const struct frag_handling *h;
1981
1982     for (h = all_frags; h < &all_frags[ARRAY_SIZE(all_frags)]; h++) {
1983         if (!strcasecmp(s, h->name)) {
1984             /* We force the upper bits of the mask on to make mf_parse_value()
1985              * happy (otherwise it will never think it's an exact match.) */
1986             *maskp = h->mask | ~FLOW_NW_FRAG_MASK;
1987             *valuep = h->value;
1988             return NULL;
1989         }
1990     }
1991
1992     return xasprintf("%s: unknown fragment type (valid types are \"no\", "
1993                      "\"yes\", \"first\", \"later\", \"not_first\"", s);
1994 }
1995
1996 /* Parses 's', a string value for field 'mf', into 'value' and 'mask'.  Returns
1997  * NULL if successful, otherwise a malloc()'d string describing the error. */
1998 char *
1999 mf_parse(const struct mf_field *mf, const char *s,
2000          union mf_value *value, union mf_value *mask)
2001 {
2002     if (!strcasecmp(s, "any") || !strcmp(s, "*")) {
2003         memset(value, 0, mf->n_bytes);
2004         memset(mask, 0, mf->n_bytes);
2005         return NULL;
2006     }
2007
2008     switch (mf->string) {
2009     case MFS_DECIMAL:
2010     case MFS_HEXADECIMAL:
2011         return mf_from_integer_string(mf, s,
2012                                       (uint8_t *) value, (uint8_t *) mask);
2013
2014     case MFS_ETHERNET:
2015         return mf_from_ethernet_string(mf, s, value->mac, mask->mac);
2016
2017     case MFS_IPV4:
2018         return mf_from_ipv4_string(mf, s, &value->be32, &mask->be32);
2019
2020     case MFS_IPV6:
2021         return mf_from_ipv6_string(mf, s, &value->ipv6, &mask->ipv6);
2022
2023     case MFS_OFP_PORT:
2024         return mf_from_ofp_port_string(mf, s, &value->be16, &mask->be16);
2025
2026     case MFS_FRAG:
2027         return mf_from_frag_string(s, &value->u8, &mask->u8);
2028     }
2029     NOT_REACHED();
2030 }
2031
2032 /* Parses 's', a string value for field 'mf', into 'value'.  Returns NULL if
2033  * successful, otherwise a malloc()'d string describing the error. */
2034 char *
2035 mf_parse_value(const struct mf_field *mf, const char *s, union mf_value *value)
2036 {
2037     union mf_value mask;
2038     char *error;
2039
2040     error = mf_parse(mf, s, value, &mask);
2041     if (error) {
2042         return error;
2043     }
2044
2045     if (!is_all_ones((const uint8_t *) &mask, mf->n_bytes)) {
2046         return xasprintf("%s: wildcards not allowed here", s);
2047     }
2048     return NULL;
2049 }
2050
2051 static void
2052 mf_format_integer_string(const struct mf_field *mf, const uint8_t *valuep,
2053                          const uint8_t *maskp, struct ds *s)
2054 {
2055     unsigned long long int integer;
2056     int i;
2057
2058     assert(mf->n_bytes <= 8);
2059
2060     integer = 0;
2061     for (i = 0; i < mf->n_bytes; i++) {
2062         integer = (integer << 8) | valuep[i];
2063     }
2064     if (mf->string == MFS_HEXADECIMAL) {
2065         ds_put_format(s, "%#llx", integer);
2066     } else {
2067         ds_put_format(s, "%lld", integer);
2068     }
2069
2070     if (maskp) {
2071         unsigned long long int mask;
2072
2073         mask = 0;
2074         for (i = 0; i < mf->n_bytes; i++) {
2075             mask = (mask << 8) | maskp[i];
2076         }
2077
2078         /* I guess we could write the mask in decimal for MFS_DECIMAL but I'm
2079          * not sure that that a bit-mask written in decimal is ever easier to
2080          * understand than the same bit-mask written in hexadecimal. */
2081         ds_put_format(s, "/%#llx", mask);
2082     }
2083 }
2084
2085 static void
2086 mf_format_frag_string(const uint8_t *valuep, const uint8_t *maskp,
2087                       struct ds *s)
2088 {
2089     const struct frag_handling *h;
2090     uint8_t value = *valuep;
2091     uint8_t mask = *maskp;
2092
2093     value &= mask;
2094     mask &= FLOW_NW_FRAG_MASK;
2095
2096     for (h = all_frags; h < &all_frags[ARRAY_SIZE(all_frags)]; h++) {
2097         if (value == h->value && mask == h->mask) {
2098             ds_put_cstr(s, h->name);
2099             return;
2100         }
2101     }
2102     ds_put_cstr(s, "<error>");
2103 }
2104
2105 /* Appends to 's' a string representation of field 'mf' whose value is in
2106  * 'value' and 'mask'.  'mask' may be NULL to indicate an exact match. */
2107 void
2108 mf_format(const struct mf_field *mf,
2109           const union mf_value *value, const union mf_value *mask,
2110           struct ds *s)
2111 {
2112     if (mask) {
2113         if (is_all_zeros((const uint8_t *) mask, mf->n_bytes)) {
2114             ds_put_cstr(s, "ANY");
2115             return;
2116         } else if (is_all_ones((const uint8_t *) mask, mf->n_bytes)) {
2117             mask = NULL;
2118         }
2119     }
2120
2121     switch (mf->string) {
2122     case MFS_OFP_PORT:
2123         if (!mask) {
2124             ofputil_format_port(ntohs(value->be16), s);
2125             break;
2126         }
2127         /* fall through */
2128     case MFS_DECIMAL:
2129     case MFS_HEXADECIMAL:
2130         mf_format_integer_string(mf, (uint8_t *) value, (uint8_t *) mask, s);
2131         break;
2132
2133     case MFS_ETHERNET:
2134         eth_format_masked(value->mac, mask->mac, s);
2135         break;
2136
2137     case MFS_IPV4:
2138         ip_format_masked(value->be32, mask ? mask->be32 : htonl(UINT32_MAX),
2139                          s);
2140         break;
2141
2142     case MFS_IPV6:
2143         print_ipv6_masked(s, &value->ipv6, mask ? &mask->ipv6 : NULL);
2144         break;
2145
2146     case MFS_FRAG:
2147         mf_format_frag_string(&value->u8, &mask->u8, s);
2148         break;
2149
2150     default:
2151         NOT_REACHED();
2152     }
2153 }
2154 \f
2155 /* Makes subfield 'sf' within 'rule' exactly match the 'sf->n_bits'
2156  * least-significant bits in 'x'.
2157  */
2158 void
2159 mf_write_subfield(const struct mf_subfield *sf, const union mf_subvalue *x,
2160                   struct cls_rule *rule)
2161 {
2162     const struct mf_field *field = sf->field;
2163     union mf_value value, mask;
2164
2165     mf_get(field, rule, &value, &mask);
2166     bitwise_copy(x, sizeof *x, 0, &value, field->n_bytes, sf->ofs, sf->n_bits);
2167     bitwise_one (                 &mask,  field->n_bytes, sf->ofs, sf->n_bits);
2168     mf_set(field, &value, &mask, rule);
2169 }
2170
2171 /* Initializes 'x' to the value of 'sf' within 'flow'.  'sf' must be valid for
2172  * reading 'flow', e.g. as checked by mf_check_src(). */
2173 void
2174 mf_read_subfield(const struct mf_subfield *sf, const struct flow *flow,
2175                  union mf_subvalue *x)
2176 {
2177     union mf_value value;
2178
2179     mf_get_value(sf->field, flow, &value);
2180
2181     memset(x, 0, sizeof *x);
2182     bitwise_copy(&value, sf->field->n_bytes, sf->ofs,
2183                  x, sizeof *x, 0,
2184                  sf->n_bits);
2185 }
2186
2187 /* Returns the value of 'sf' within 'flow'.  'sf' must be valid for reading
2188  * 'flow', e.g. as checked by mf_check_src() and sf->n_bits must be 64 or
2189  * less. */
2190 uint64_t
2191 mf_get_subfield(const struct mf_subfield *sf, const struct flow *flow)
2192 {
2193     union mf_value value;
2194
2195     mf_get_value(sf->field, flow, &value);
2196     return bitwise_get(&value, sf->field->n_bytes, sf->ofs, sf->n_bits);
2197 }
2198
2199 /* Formats 'sf' into 's' in a format normally acceptable to
2200  * mf_parse_subfield().  (It won't be acceptable if sf->field is NULL or if
2201  * sf->field has no NXM name.) */
2202 void
2203 mf_format_subfield(const struct mf_subfield *sf, struct ds *s)
2204 {
2205     if (!sf->field) {
2206         ds_put_cstr(s, "<unknown>");
2207     } else if (sf->field->nxm_name) {
2208         ds_put_cstr(s, sf->field->nxm_name);
2209     } else if (sf->field->nxm_header) {
2210         uint32_t header = sf->field->nxm_header;
2211         ds_put_format(s, "%d:%d", NXM_VENDOR(header), NXM_FIELD(header));
2212     } else {
2213         ds_put_cstr(s, sf->field->name);
2214     }
2215
2216     if (sf->field && sf->ofs == 0 && sf->n_bits == sf->field->n_bits) {
2217         ds_put_cstr(s, "[]");
2218     } else if (sf->n_bits == 1) {
2219         ds_put_format(s, "[%d]", sf->ofs);
2220     } else {
2221         ds_put_format(s, "[%d..%d]", sf->ofs, sf->ofs + sf->n_bits - 1);
2222     }
2223 }
2224
2225 static const struct mf_field *
2226 mf_parse_subfield_name(const char *name, int name_len, bool *wild)
2227 {
2228     int i;
2229
2230     *wild = name_len > 2 && !memcmp(&name[name_len - 2], "_W", 2);
2231     if (*wild) {
2232         name_len -= 2;
2233     }
2234
2235     for (i = 0; i < MFF_N_IDS; i++) {
2236         const struct mf_field *mf = mf_from_id(i);
2237
2238         if (mf->nxm_name
2239             && !strncmp(mf->nxm_name, name, name_len)
2240             && mf->nxm_name[name_len] == '\0') {
2241             return mf;
2242         }
2243         if (mf->oxm_name
2244             && !strncmp(mf->oxm_name, name, name_len)
2245             && mf->oxm_name[name_len] == '\0') {
2246             return mf;
2247         }
2248     }
2249
2250     return NULL;
2251 }
2252
2253 /* Parses a subfield from the beginning of '*sp' into 'sf'.  If successful,
2254  * returns NULL and advances '*sp' to the first byte following the parsed
2255  * string.  On failure, returns a malloc()'d error message, does not modify
2256  * '*sp', and does not properly initialize 'sf'.
2257  *
2258  * The syntax parsed from '*sp' takes the form "header[start..end]" where
2259  * 'header' is the name of an NXM field and 'start' and 'end' are (inclusive)
2260  * bit indexes.  "..end" may be omitted to indicate a single bit.  "start..end"
2261  * may both be omitted (the [] are still required) to indicate an entire
2262  * field. */
2263 char *
2264 mf_parse_subfield__(struct mf_subfield *sf, const char **sp)
2265 {
2266     const struct mf_field *field;
2267     const char *name;
2268     int start, end;
2269     const char *s;
2270     int name_len;
2271     bool wild;
2272
2273     s = *sp;
2274     name = s;
2275     name_len = strcspn(s, "[");
2276     if (s[name_len] != '[') {
2277         return xasprintf("%s: missing [ looking for field name", *sp);
2278     }
2279
2280     field = mf_parse_subfield_name(name, name_len, &wild);
2281     if (!field) {
2282         return xasprintf("%s: unknown field `%.*s'", *sp, name_len, s);
2283     }
2284
2285     s += name_len;
2286     if (sscanf(s, "[%d..%d]", &start, &end) == 2) {
2287         /* Nothing to do. */
2288     } else if (sscanf(s, "[%d]", &start) == 1) {
2289         end = start;
2290     } else if (!strncmp(s, "[]", 2)) {
2291         start = 0;
2292         end = field->n_bits - 1;
2293     } else {
2294         return xasprintf("%s: syntax error expecting [] or [<bit>] or "
2295                          "[<start>..<end>]", *sp);
2296     }
2297     s = strchr(s, ']') + 1;
2298
2299     if (start > end) {
2300         return xasprintf("%s: starting bit %d is after ending bit %d",
2301                          *sp, start, end);
2302     } else if (start >= field->n_bits) {
2303         return xasprintf("%s: starting bit %d is not valid because field is "
2304                          "only %d bits wide", *sp, start, field->n_bits);
2305     } else if (end >= field->n_bits){
2306         return xasprintf("%s: ending bit %d is not valid because field is "
2307                          "only %d bits wide", *sp, end, field->n_bits);
2308     }
2309
2310     sf->field = field;
2311     sf->ofs = start;
2312     sf->n_bits = end - start + 1;
2313
2314     *sp = s;
2315     return NULL;
2316 }
2317
2318 /* Parses a subfield from the beginning of 's' into 'sf'.  Returns the first
2319  * byte in 's' following the parsed string.
2320  *
2321  * Exits with an error message if 's' has incorrect syntax.
2322  *
2323  * The syntax parsed from 's' takes the form "header[start..end]" where
2324  * 'header' is the name of an NXM field and 'start' and 'end' are (inclusive)
2325  * bit indexes.  "..end" may be omitted to indicate a single bit.  "start..end"
2326  * may both be omitted (the [] are still required) to indicate an entire
2327  * field.  */
2328 const char *
2329 mf_parse_subfield(struct mf_subfield *sf, const char *s)
2330 {
2331     char *msg = mf_parse_subfield__(sf, &s);
2332     if (msg) {
2333         ovs_fatal(0, "%s", msg);
2334     }
2335     return s;
2336 }