lib/meta-flow.c

   1 /*
   2  * Copyright (c) 2011 Nicira Networks.
   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-util.h"
  30 #include "packets.h"
  31 #include "random.h"
  32 #include "shash.h"
  33 #include "socket-util.h"
  34 #include "unaligned.h"
  35
  36 #define MF_FIELD_SIZES(MEMBER)                  \
  37     sizeof ((union mf_value *)0)->MEMBER,       \
  38     8 * sizeof ((union mf_value *)0)->MEMBER
  39
  40 static const struct mf_field mf_fields[MFF_N_IDS] = {
  41     /* ## -------- ## */
  42     /* ## metadata ## */
  43     /* ## -------- ## */
  44
  45     {
  46         MFF_TUN_ID, "tun_id", NULL,
  47         MF_FIELD_SIZES(be64),
  48         MFM_FULLY, 0,
  49         MFS_HEXADECIMAL,
  50         MFP_NONE,
  51         NXM_NX_TUN_ID,
  52     }, {
  53         MFF_IN_PORT, "in_port", NULL,
  54         MF_FIELD_SIZES(be16),
  55         MFM_NONE, FWW_IN_PORT,
  56         MFS_OFP_PORT,
  57         MFP_NONE,
  58         NXM_OF_IN_PORT,
  59     },
  60
  61 #define REGISTER(IDX)                           \
  62     {                                           \
  63         MFF_REG##IDX, "reg" #IDX, NULL,         \
  64         MF_FIELD_SIZES(be32),                   \
  65         MFM_FULLY, 0,                           \
  66         MFS_HEXADECIMAL,                        \
  67         MFP_NONE,                               \
  68         NXM_NX_REG(IDX),                        \
  69     }
  70 #if FLOW_N_REGS > 0
  71     REGISTER(0),
  72 #endif
  73 #if FLOW_N_REGS > 1
  74     REGISTER(1),
  75 #endif
  76 #if FLOW_N_REGS > 2
  77     REGISTER(2),
  78 #endif
  79 #if FLOW_N_REGS > 3
  80     REGISTER(3),
  81 #endif
  82 #if FLOW_N_REGS > 4
  83     REGISTER(4),
  84 #endif
  85 #if FLOW_N_REGS > 5
  86 #error
  87 #endif
  88
  89     /* ## -- ## */
  90     /* ## L2 ## */
  91     /* ## -- ## */
  92
  93     {
  94         MFF_ETH_SRC, "eth_src", "dl_src",
  95         MF_FIELD_SIZES(mac),
  96         MFM_NONE, FWW_DL_SRC,
  97         MFS_ETHERNET,
  98         MFP_NONE,
  99         NXM_OF_ETH_SRC,
 100     }, {
 101         MFF_ETH_DST, "eth_dst", "dl_dst",
 102         MF_FIELD_SIZES(mac),
 103         MFM_MCAST, 0,
 104         MFS_ETHERNET,
 105         MFP_NONE,
 106         NXM_OF_ETH_DST,
 107     }, {
 108         MFF_ETH_TYPE, "eth_type", "dl_type",
 109         MF_FIELD_SIZES(be16),
 110         MFM_NONE, FWW_DL_TYPE,
 111         MFS_HEXADECIMAL,
 112         MFP_NONE,
 113         NXM_OF_ETH_TYPE,
 114     },
 115
 116     {
 117         MFF_VLAN_TCI, "vlan_tci", NULL,
 118         MF_FIELD_SIZES(be16),
 119         MFM_FULLY, 0,
 120         MFS_HEXADECIMAL,
 121         MFP_NONE,
 122         NXM_OF_VLAN_TCI,
 123     }, {
 124         MFF_VLAN_VID, "dl_vlan", NULL,
 125         sizeof(ovs_be16), 12,
 126         MFM_NONE, 0,
 127         MFS_DECIMAL,
 128         MFP_NONE,
 129         0,
 130     }, {
 131         MFF_VLAN_PCP, "dl_vlan_pcp", NULL,
 132         1, 3,
 133         MFM_NONE, 0,
 134         MFS_DECIMAL,
 135         MFP_NONE,
 136         0,
 137     },
 138
 139     /* ## -- ## */
 140     /* ## L3 ## */
 141     /* ## -- ## */
 142
 143     {
 144         MFF_IPV4_SRC, "ip_src", "nw_src",
 145         MF_FIELD_SIZES(be32),
 146         MFM_CIDR, 0,
 147         MFS_IPV4,
 148         MFP_IPV4,
 149         NXM_OF_IP_SRC,
 150     }, {
 151         MFF_IPV4_DST, "ip_dst", "nw_dst",
 152         MF_FIELD_SIZES(be32),
 153         MFM_CIDR, 0,
 154         MFS_IPV4,
 155         MFP_IPV4,
 156         NXM_OF_IP_DST,
 157     },
 158
 159     {
 160         MFF_IPV6_SRC, "ipv6_src", NULL,
 161         MF_FIELD_SIZES(ipv6),
 162         MFM_CIDR, 0,
 163         MFS_IPV6,
 164         MFP_IPV6,
 165         NXM_NX_IPV6_SRC,
 166     }, {
 167         MFF_IPV6_DST, "ipv6_dst", NULL,
 168         MF_FIELD_SIZES(ipv6),
 169         MFM_CIDR, 0,
 170         MFS_IPV6,
 171         MFP_IPV6,
 172         NXM_NX_IPV6_DST,
 173     },
 174
 175     {
 176         MFF_IP_PROTO, "nw_proto", NULL,
 177         MF_FIELD_SIZES(u8),
 178         MFM_NONE, FWW_NW_PROTO,
 179         MFS_DECIMAL,
 180         MFP_IP_ANY,
 181         NXM_OF_IP_PROTO,
 182     }, {
 183         MFF_IP_TOS, "nw_tos", NULL,
 184         MF_FIELD_SIZES(u8),
 185         MFM_NONE, FWW_NW_TOS,
 186         MFS_DECIMAL,
 187         MFP_IP_ANY,
 188         NXM_OF_IP_TOS,
 189     },
 190
 191     {
 192         MFF_ARP_OP, "arp_op", NULL,
 193         MF_FIELD_SIZES(be16),
 194         MFM_NONE, FWW_NW_PROTO,
 195         MFS_DECIMAL,
 196         MFP_ARP,
 197         NXM_OF_ARP_OP,
 198     }, {
 199         MFF_ARP_SPA, "arp_spa", NULL,
 200         MF_FIELD_SIZES(be32),
 201         MFM_CIDR, 0,
 202         MFS_IPV4,
 203         MFP_ARP,
 204         NXM_OF_ARP_SPA,
 205     }, {
 206         MFF_ARP_TPA, "arp_tpa", NULL,
 207         MF_FIELD_SIZES(be32),
 208         MFM_CIDR, 0,
 209         MFS_IPV4,
 210         MFP_ARP,
 211         NXM_OF_ARP_TPA,
 212     }, {
 213         MFF_ARP_SHA, "arp_sha", NULL,
 214         MF_FIELD_SIZES(mac),
 215         MFM_NONE, FWW_ARP_SHA,
 216         MFS_ETHERNET,
 217         MFP_ARP,
 218         NXM_NX_ARP_SHA,
 219     }, {
 220         MFF_ARP_THA, "arp_tha", NULL,
 221         MF_FIELD_SIZES(mac),
 222         MFM_NONE, FWW_ARP_THA,
 223         MFS_ETHERNET,
 224         MFP_ARP,
 225         NXM_NX_ARP_THA,
 226     },
 227
 228     /* ## -- ## */
 229     /* ## L4 ## */
 230     /* ## -- ## */
 231
 232     {
 233         MFF_TCP_SRC, "tcp_src", "tp_src",
 234         MF_FIELD_SIZES(be16),
 235         MFM_NONE, FWW_TP_SRC,
 236         MFS_DECIMAL,
 237         MFP_TCP,
 238         NXM_OF_TCP_SRC,
 239     }, {
 240         MFF_TCP_DST, "tcp_dst", "tp_dst",
 241         MF_FIELD_SIZES(be16),
 242         MFM_NONE, FWW_TP_DST,
 243         MFS_DECIMAL,
 244         MFP_TCP,
 245         NXM_OF_TCP_DST,
 246     },
 247
 248     {
 249         MFF_UDP_SRC, "udp_src", NULL,
 250         MF_FIELD_SIZES(be16),
 251         MFM_NONE, FWW_TP_SRC,
 252         MFS_DECIMAL,
 253         MFP_UDP,
 254         NXM_OF_UDP_SRC,
 255     }, {
 256         MFF_UDP_DST, "udp_dst", NULL,
 257         MF_FIELD_SIZES(be16),
 258         MFM_NONE, FWW_TP_DST,
 259         MFS_DECIMAL,
 260         MFP_UDP,
 261         NXM_OF_UDP_DST,
 262     },
 263
 264     {
 265         MFF_ICMP_TYPE, "icmp_type", NULL,
 266         MF_FIELD_SIZES(u8),
 267         MFM_NONE, FWW_TP_SRC,
 268         MFS_DECIMAL,
 269         MFP_ICMP_ANY,
 270         NXM_OF_ICMP_TYPE,
 271     }, {
 272         MFF_ICMP_CODE, "icmp_code", NULL,
 273         MF_FIELD_SIZES(u8),
 274         MFM_NONE, FWW_TP_DST,
 275         MFS_DECIMAL,
 276         MFP_ICMP_ANY,
 277         NXM_OF_ICMP_CODE,
 278     },
 279
 280     /* ## ---- ## */
 281     /* ## L"5" ## */
 282     /* ## ---- ## */
 283
 284     {
 285         MFF_ND_TARGET, "nd_target", NULL,
 286         MF_FIELD_SIZES(ipv6),
 287         MFM_NONE, FWW_ND_TARGET,
 288         MFS_IPV6,
 289         MFP_ND,
 290         NXM_NX_ND_TARGET,
 291     }, {
 292         MFF_ND_SLL, "nd_sll", NULL,
 293         MF_FIELD_SIZES(mac),
 294         MFM_NONE, FWW_ARP_SHA,
 295         MFS_ETHERNET,
 296         MFP_ND_SOLICIT,
 297         NXM_NX_ND_SLL,
 298     }, {
 299         MFF_ND_TLL, "nd_tll", NULL,
 300         MF_FIELD_SIZES(mac),
 301         MFM_NONE, FWW_ARP_THA,
 302         MFS_ETHERNET,
 303         MFP_ND_ADVERT,
 304         NXM_NX_ND_TLL,
 305     }
 306 };
 307
 308 /* Returns the field with the given 'id'. */
 309 const struct mf_field *
 310 mf_from_id(enum mf_field_id id)
 311 {
 312     assert((unsigned int) id < MFF_N_IDS);
 313     return &mf_fields[id];
 314 }
 315
 316 /* Returns the field with the given 'name', or a null pointer if no field has
 317  * that name. */
 318 const struct mf_field *
 319 mf_from_name(const char *name)
 320 {
 321     static struct shash mf_by_name = SHASH_INITIALIZER(&mf_by_name);
 322
 323     if (shash_is_empty(&mf_by_name)) {
 324         const struct mf_field *mf;
 325
 326         for (mf = mf_fields; mf < &mf_fields[MFF_N_IDS]; mf++) {
 327             shash_add_once(&mf_by_name, mf->name, mf);
 328             if (mf->extra_name) {
 329                 shash_add_once(&mf_by_name, mf->extra_name, mf);
 330             }
 331         }
 332     }
 333
 334     return shash_find_data(&mf_by_name, name);
 335 }
 336
 337 /* Returns true if 'wc' wildcards all the bits in field 'mf', false if 'wc'
 338  * specifies at least one bit in the field.
 339  *
 340  * The caller is responsible for ensuring that 'wc' corresponds to a flow that
 341  * meets 'mf''s prerequisites. */
 342 bool
 343 mf_is_all_wild(const struct mf_field *mf, const struct flow_wildcards *wc)
 344 {
 345     switch (mf->id) {
 346     case MFF_IN_PORT:
 347     case MFF_ETH_SRC:
 348     case MFF_ETH_TYPE:
 349     case MFF_IP_PROTO:
 350     case MFF_IP_TOS:
 351     case MFF_ARP_OP:
 352     case MFF_ARP_SHA:
 353     case MFF_ARP_THA:
 354     case MFF_TCP_SRC:
 355     case MFF_TCP_DST:
 356     case MFF_UDP_SRC:
 357     case MFF_UDP_DST:
 358     case MFF_ICMP_TYPE:
 359     case MFF_ICMP_CODE:
 360     case MFF_ND_TARGET:
 361     case MFF_ND_SLL:
 362     case MFF_ND_TLL:
 363         assert(mf->fww_bit != 0);
 364         return (wc->wildcards & mf->fww_bit) != 0;
 365
 366     case MFF_TUN_ID:
 367         return !wc->tun_id_mask;
 368
 369 #if FLOW_N_REGS > 0
 370     case MFF_REG0:
 371 #endif
 372 #if FLOW_N_REGS > 1
 373     case MFF_REG1:
 374 #endif
 375 #if FLOW_N_REGS > 2
 376     case MFF_REG2:
 377 #endif
 378 #if FLOW_N_REGS > 3
 379     case MFF_REG3:
 380 #endif
 381 #if FLOW_N_REGS > 4
 382     case MFF_REG4:
 383 #endif
 384 #if FLOW_N_REGS > 5
 385 #error
 386 #endif
 387         return !wc->reg_masks[mf->id - MFF_REG0];
 388
 389     case MFF_ETH_DST:
 390         return ((wc->wildcards & (FWW_ETH_MCAST | FWW_DL_DST))
 391                 == (FWW_ETH_MCAST | FWW_DL_DST));
 392
 393     case MFF_VLAN_TCI:
 394         return !wc->vlan_tci_mask;
 395     case MFF_VLAN_VID:
 396         return !(wc->vlan_tci_mask & htons(VLAN_VID_MASK));
 397     case MFF_VLAN_PCP:
 398         return !(wc->vlan_tci_mask & htons(VLAN_PCP_MASK));
 399
 400     case MFF_IPV4_SRC:
 401         return !wc->nw_src_mask;
 402     case MFF_IPV4_DST:
 403         return !wc->nw_dst_mask;
 404
 405     case MFF_IPV6_SRC:
 406         return ipv6_mask_is_any(&wc->ipv6_src_mask);
 407     case MFF_IPV6_DST:
 408         return ipv6_mask_is_any(&wc->ipv6_dst_mask);
 409
 410     case MFF_ARP_SPA:
 411         return !wc->nw_src_mask;
 412     case MFF_ARP_TPA:
 413         return !wc->nw_dst_mask;
 414
 415     case MFF_N_IDS:
 416     default:
 417         NOT_REACHED();
 418     }
 419 }
 420
 421 /* Initializes 'mask' with the wildcard bit pattern for field 'mf' within 'wc'.
 422  * Each bit in 'mask' will be set to 1 if the bit is significant for matching
 423  * purposes, or to 0 if it is wildcarded.
 424  *
 425  * The caller is responsible for ensuring that 'wc' corresponds to a flow that
 426  * meets 'mf''s prerequisites. */
 427 void
 428 mf_get_mask(const struct mf_field *mf, const struct flow_wildcards *wc,
 429             union mf_value *mask)
 430 {
 431     switch (mf->id) {
 432     case MFF_IN_PORT:
 433     case MFF_ETH_SRC:
 434     case MFF_ETH_TYPE:
 435     case MFF_IP_PROTO:
 436     case MFF_IP_TOS:
 437     case MFF_ARP_OP:
 438     case MFF_ARP_SHA:
 439     case MFF_ARP_THA:
 440     case MFF_TCP_SRC:
 441     case MFF_TCP_DST:
 442     case MFF_UDP_SRC:
 443     case MFF_UDP_DST:
 444     case MFF_ICMP_TYPE:
 445     case MFF_ICMP_CODE:
 446     case MFF_ND_TARGET:
 447     case MFF_ND_SLL:
 448     case MFF_ND_TLL:
 449         assert(mf->fww_bit != 0);
 450         memset(mask, wc->wildcards & mf->fww_bit ? 0x00 : 0xff, mf->n_bytes);
 451         break;
 452
 453     case MFF_TUN_ID:
 454         mask->be64 = wc->tun_id_mask;
 455         break;
 456
 457 #if FLOW_N_REGS > 0
 458     case MFF_REG0:
 459 #endif
 460 #if FLOW_N_REGS > 1
 461     case MFF_REG1:
 462 #endif
 463 #if FLOW_N_REGS > 2
 464     case MFF_REG2:
 465 #endif
 466 #if FLOW_N_REGS > 3
 467     case MFF_REG3:
 468 #endif
 469 #if FLOW_N_REGS > 4
 470     case MFF_REG4:
 471 #endif
 472 #if FLOW_N_REGS > 5
 473 #error
 474 #endif
 475         mask->be32 = htonl(wc->reg_masks[mf->id - MFF_REG0]);
 476         break;
 477
 478     case MFF_ETH_DST:
 479         memcpy(mask->mac, flow_wildcards_to_dl_dst_mask(wc->wildcards),
 480                ETH_ADDR_LEN);
 481         break;
 482
 483     case MFF_VLAN_TCI:
 484         mask->be16 = wc->vlan_tci_mask;
 485         break;
 486     case MFF_VLAN_VID:
 487         mask->be16 = wc->vlan_tci_mask & htons(VLAN_VID_MASK);
 488         break;
 489     case MFF_VLAN_PCP:
 490         mask->u8 = vlan_tci_to_pcp(wc->vlan_tci_mask);
 491         break;
 492
 493     case MFF_IPV4_SRC:
 494         mask->be32 = wc->nw_src_mask;
 495         break;
 496     case MFF_IPV4_DST:
 497         mask->be32 = wc->nw_dst_mask;
 498         break;
 499
 500     case MFF_IPV6_SRC:
 501         mask->ipv6 = wc->ipv6_src_mask;
 502         break;
 503     case MFF_IPV6_DST:
 504         mask->ipv6 = wc->ipv6_dst_mask;
 505         break;
 506
 507     case MFF_ARP_SPA:
 508         mask->be32 = wc->nw_src_mask;
 509         break;
 510     case MFF_ARP_TPA:
 511         mask->be32 = wc->nw_dst_mask;
 512         break;
 513
 514     case MFF_N_IDS:
 515     default:
 516         NOT_REACHED();
 517     }
 518 }
 519
 520 /* Tests whether 'mask' is a valid wildcard bit pattern for 'mf'.  Returns true
 521  * if the mask is valid, false otherwise. */
 522 bool
 523 mf_is_mask_valid(const struct mf_field *mf, const union mf_value *mask)
 524 {
 525     switch (mf->maskable) {
 526     case MFM_NONE:
 527         return (is_all_zeros((const uint8_t *) mask, mf->n_bytes) ||
 528                 is_all_ones((const uint8_t *) mask, mf->n_bytes));
 529
 530     case MFM_FULLY:
 531         return true;
 532
 533     case MFM_CIDR:
 534         return (mf->n_bytes == 4
 535                 ? ip_is_cidr(mask->be32)
 536                 : ipv6_is_cidr(&mask->ipv6));
 537
 538     case MFM_MCAST:
 539         return flow_wildcards_is_dl_dst_mask_valid(mask->mac);
 540     }
 541
 542     NOT_REACHED();
 543 }
 544
 545 static bool
 546 is_ip_any(const struct flow *flow)
 547 {
 548     return (flow->dl_type == htons(ETH_TYPE_IP) ||
 549             flow->dl_type == htons(ETH_TYPE_IPV6));
 550 }
 551
 552 static bool
 553 is_icmpv4(const struct flow *flow)
 554 {
 555     return (flow->dl_type == htons(ETH_TYPE_IP)
 556             && flow->nw_proto == IPPROTO_ICMP);
 557 }
 558
 559 static bool
 560 is_icmpv6(const struct flow *flow)
 561 {
 562     return (flow->dl_type == htons(ETH_TYPE_IPV6)
 563             && flow->nw_proto == IPPROTO_ICMPV6);
 564 }
 565
 566 /* Returns true if 'flow' meets the prerequisites for 'mf', false otherwise. */
 567 bool
 568 mf_are_prereqs_ok(const struct mf_field *mf, const struct flow *flow)
 569 {
 570     switch (mf->prereqs) {
 571     case MFP_NONE:
 572         return true;
 573
 574     case MFP_ARP:
 575         return flow->dl_type == htons(ETH_TYPE_ARP);
 576     case MFP_IPV4:
 577         return flow->dl_type == htons(ETH_TYPE_IP);
 578     case MFP_IPV6:
 579         return flow->dl_type == htons(ETH_TYPE_IPV6);
 580     case MFP_IP_ANY:
 581         return is_ip_any(flow);
 582
 583     case MFP_TCP:
 584         return is_ip_any(flow) && flow->nw_proto == IPPROTO_TCP;
 585     case MFP_UDP:
 586         return is_ip_any(flow) && flow->nw_proto == IPPROTO_UDP;
 587     case MFP_ICMPV6:
 588         return is_icmpv6(flow);
 589     case MFP_ICMP_ANY:
 590         return is_icmpv4(flow) || is_icmpv6(flow);
 591
 592     case MFP_ND:
 593         return (is_icmpv6(flow)
 594                 && flow->tp_dst == htons(0)
 595                 && (flow->tp_src == htons(ND_NEIGHBOR_SOLICIT) ||
 596                     flow->tp_src == htons(ND_NEIGHBOR_ADVERT)));
 597     case MFP_ND_SOLICIT:
 598         return (is_icmpv6(flow)
 599                 && flow->tp_dst == htons(0)
 600                 && (flow->tp_src == htons(ND_NEIGHBOR_SOLICIT)));
 601     case MFP_ND_ADVERT:
 602         return (is_icmpv6(flow)
 603                 && flow->tp_dst == htons(0)
 604                 && (flow->tp_src == htons(ND_NEIGHBOR_ADVERT)));
 605     }
 606
 607     NOT_REACHED();
 608 }
 609
 610 /* Returns true if 'value' may be a valid value *as part of a masked match*,
 611  * false otherwise.
 612  *
 613  * A value is not rejected just because it is not valid for the field in
 614  * question, but only if it doesn't make sense to test the bits in question at
 615  * all.  For example, the MFF_VLAN_TCI field will never have a nonzero value
 616  * without the VLAN_CFI bit being set, but we can't reject those values because
 617  * it is still legitimate to test just for those bits (see the documentation
 618  * for NXM_OF_VLAN_TCI in nicira-ext.h).  On the other hand, there is never a
 619  * reason to set the low bit of MFF_IP_TOS to 1, so we reject that. */
 620 bool
 621 mf_is_value_valid(const struct mf_field *mf, const union mf_value *value)
 622 {
 623     switch (mf->id) {
 624     case MFF_TUN_ID:
 625     case MFF_IN_PORT:
 626 #if FLOW_N_REGS > 0
 627     case MFF_REG0:
 628 #endif
 629 #if FLOW_N_REGS > 1
 630     case MFF_REG1:
 631 #endif
 632 #if FLOW_N_REGS > 2
 633     case MFF_REG2:
 634 #endif
 635 #if FLOW_N_REGS > 3
 636     case MFF_REG3:
 637 #endif
 638 #if FLOW_N_REGS > 4
 639     case MFF_REG4:
 640 #endif
 641 #if FLOW_N_REGS > 5
 642 #error
 643 #endif
 644     case MFF_ETH_SRC:
 645     case MFF_ETH_DST:
 646     case MFF_ETH_TYPE:
 647     case MFF_VLAN_TCI:
 648     case MFF_IPV4_SRC:
 649     case MFF_IPV4_DST:
 650     case MFF_IPV6_SRC:
 651     case MFF_IPV6_DST:
 652     case MFF_IP_PROTO:
 653     case MFF_ARP_SPA:
 654     case MFF_ARP_TPA:
 655     case MFF_ARP_SHA:
 656     case MFF_ARP_THA:
 657     case MFF_TCP_SRC:
 658     case MFF_TCP_DST:
 659     case MFF_UDP_SRC:
 660     case MFF_UDP_DST:
 661     case MFF_ICMP_TYPE:
 662     case MFF_ICMP_CODE:
 663     case MFF_ND_TARGET:
 664     case MFF_ND_SLL:
 665     case MFF_ND_TLL:
 666         return true;
 667
 668     case MFF_IP_TOS:
 669         return !(value->u8 & 0x03);
 670
 671     case MFF_ARP_OP:
 672         return !(value->be16 & htons(0xff00));
 673
 674     case MFF_VLAN_VID:
 675         return !(value->be16 & htons(VLAN_CFI | VLAN_PCP_MASK));
 676
 677     case MFF_VLAN_PCP:
 678         return !(value->u8 & ~7);
 679
 680     case MFF_N_IDS:
 681     default:
 682         NOT_REACHED();
 683     }
 684 }
 685
 686 /* Copies the value of field 'mf' from 'flow' into 'value'.  The caller is
 687  * responsible for ensuring that 'flow' meets 'mf''s prerequisites. */
 688 void
 689 mf_get_value(const struct mf_field *mf, const struct flow *flow,
 690              union mf_value *value)
 691 {
 692     switch (mf->id) {
 693     case MFF_TUN_ID:
 694         value->be64 = flow->tun_id;
 695         break;
 696
 697     case MFF_IN_PORT:
 698         value->be16 = htons(flow->in_port);
 699         break;
 700
 701 #if FLOW_N_REGS > 0
 702     case MFF_REG0:
 703 #endif
 704 #if FLOW_N_REGS > 1
 705     case MFF_REG1:
 706 #endif
 707 #if FLOW_N_REGS > 2
 708     case MFF_REG2:
 709 #endif
 710 #if FLOW_N_REGS > 3
 711     case MFF_REG3:
 712 #endif
 713 #if FLOW_N_REGS > 4
 714     case MFF_REG4:
 715 #endif
 716 #if FLOW_N_REGS > 5
 717 #error
 718 #endif
 719         value->be32 = htonl(flow->regs[mf->id - MFF_REG0]);
 720         break;
 721
 722     case MFF_ETH_SRC:
 723         memcpy(value->mac, flow->dl_src, ETH_ADDR_LEN);
 724         break;
 725
 726     case MFF_ETH_DST:
 727         memcpy(value->mac, flow->dl_dst, ETH_ADDR_LEN);
 728         break;
 729
 730     case MFF_ETH_TYPE:
 731         value->be16 = flow->dl_type;
 732         break;
 733
 734     case MFF_VLAN_TCI:
 735         value->be16 = flow->vlan_tci;
 736         break;
 737
 738     case MFF_VLAN_VID:
 739         value->be16 = flow->vlan_tci & htons(VLAN_VID_MASK);
 740         break;
 741
 742     case MFF_VLAN_PCP:
 743         value->u8 = vlan_tci_to_pcp(flow->vlan_tci);
 744         break;
 745
 746     case MFF_IPV4_SRC:
 747         value->be32 = flow->nw_src;
 748         break;
 749
 750     case MFF_IPV4_DST:
 751         value->be32 = flow->nw_dst;
 752         break;
 753
 754     case MFF_IPV6_SRC:
 755         value->ipv6 = flow->ipv6_src;
 756         break;
 757
 758     case MFF_IPV6_DST:
 759         value->ipv6 = flow->ipv6_dst;
 760         break;
 761
 762     case MFF_IP_PROTO:
 763         value->u8 = flow->nw_proto;
 764         break;
 765
 766     case MFF_IP_TOS:
 767         value->u8 = flow->nw_tos;
 768         break;
 769
 770     case MFF_ARP_OP:
 771         value->be16 = htons(flow->nw_proto);
 772         break;
 773
 774     case MFF_ARP_SPA:
 775         value->be32 = flow->nw_src;
 776         break;
 777
 778     case MFF_ARP_TPA:
 779         value->be32 = flow->nw_dst;
 780         break;
 781
 782     case MFF_ARP_SHA:
 783     case MFF_ND_SLL:
 784         memcpy(value->mac, flow->arp_sha, ETH_ADDR_LEN);
 785         break;
 786
 787     case MFF_ARP_THA:
 788     case MFF_ND_TLL:
 789         memcpy(value->mac, flow->arp_tha, ETH_ADDR_LEN);
 790         break;
 791
 792     case MFF_TCP_SRC:
 793         value->be16 = flow->tp_src;
 794         break;
 795
 796     case MFF_TCP_DST:
 797         value->be16 = flow->tp_dst;
 798         break;
 799
 800     case MFF_UDP_SRC:
 801         value->be16 = flow->tp_src;
 802         break;
 803
 804     case MFF_UDP_DST:
 805         value->be16 = flow->tp_dst;
 806         break;
 807
 808     case MFF_ICMP_TYPE:
 809         value->u8 = ntohs(flow->tp_src);
 810         break;
 811
 812     case MFF_ICMP_CODE:
 813         value->u8 = ntohs(flow->tp_dst);
 814         break;
 815
 816     case MFF_ND_TARGET:
 817         value->ipv6 = flow->nd_target;
 818         break;
 819
 820     case MFF_N_IDS:
 821     default:
 822         NOT_REACHED();
 823     }
 824 }
 825
 826 /* Makes 'rule' match field 'mf' exactly, with the value matched taken from
 827  * 'value'.  The caller is responsible for ensuring that 'rule' meets 'mf''s
 828  * prerequisites. */
 829 void
 830 mf_set_value(const struct mf_field *mf,
 831              const union mf_value *value, struct cls_rule *rule)
 832 {
 833     switch (mf->id) {
 834     case MFF_TUN_ID:
 835         cls_rule_set_tun_id(rule, value->be64);
 836         break;
 837
 838     case MFF_IN_PORT:
 839         cls_rule_set_in_port(rule, ntohs(value->be16));
 840         break;
 841
 842 #if FLOW_N_REGS > 0
 843     case MFF_REG0:
 844 #endif
 845 #if FLOW_N_REGS > 1
 846     case MFF_REG1:
 847 #endif
 848 #if FLOW_N_REGS > 2
 849     case MFF_REG2:
 850 #endif
 851 #if FLOW_N_REGS > 3
 852     case MFF_REG3:
 853 #endif
 854 #if FLOW_N_REGS > 4
 855     case MFF_REG4:
 856 #endif
 857 #if FLOW_N_REGS > 5
 858 #error
 859 #endif
 860 #if FLOW_N_REGS > 0
 861         cls_rule_set_reg(rule, mf->id - MFF_REG0, ntohl(value->be32));
 862         break;
 863 #endif
 864
 865     case MFF_ETH_SRC:
 866         cls_rule_set_dl_src(rule, value->mac);
 867         break;
 868
 869     case MFF_ETH_DST:
 870         cls_rule_set_dl_dst(rule, value->mac);
 871         break;
 872
 873     case MFF_ETH_TYPE:
 874         cls_rule_set_dl_type(rule, value->be16);
 875         break;
 876
 877     case MFF_VLAN_TCI:
 878         cls_rule_set_dl_tci(rule, value->be16);
 879         break;
 880
 881     case MFF_VLAN_VID:
 882         cls_rule_set_dl_vlan(rule, value->be16);
 883         break;
 884
 885     case MFF_VLAN_PCP:
 886         cls_rule_set_dl_vlan_pcp(rule, value->u8);
 887         break;
 888
 889     case MFF_IPV4_SRC:
 890         cls_rule_set_nw_src(rule, value->be32);
 891         break;
 892
 893     case MFF_IPV4_DST:
 894         cls_rule_set_nw_dst(rule, value->be32);
 895         break;
 896
 897     case MFF_IPV6_SRC:
 898         cls_rule_set_ipv6_src(rule, &value->ipv6);
 899         break;
 900
 901     case MFF_IPV6_DST:
 902         cls_rule_set_ipv6_dst(rule, &value->ipv6);
 903         break;
 904
 905     case MFF_IP_PROTO:
 906         cls_rule_set_nw_proto(rule, value->u8);
 907         break;
 908
 909     case MFF_IP_TOS:
 910         cls_rule_set_nw_tos(rule, value->u8);
 911         break;
 912
 913     case MFF_ARP_OP:
 914         cls_rule_set_nw_proto(rule, ntohs(value->be16));
 915         break;
 916
 917     case MFF_ARP_SPA:
 918         cls_rule_set_nw_src(rule, value->be32);
 919         break;
 920
 921     case MFF_ARP_TPA:
 922         cls_rule_set_nw_dst(rule, value->be32);
 923         break;
 924
 925     case MFF_ARP_SHA:
 926     case MFF_ND_SLL:
 927         cls_rule_set_arp_sha(rule, value->mac);
 928         break;
 929
 930     case MFF_ARP_THA:
 931     case MFF_ND_TLL:
 932         cls_rule_set_arp_tha(rule, value->mac);
 933         break;
 934
 935     case MFF_TCP_SRC:
 936         cls_rule_set_tp_src(rule, value->be16);
 937         break;
 938
 939     case MFF_TCP_DST:
 940         cls_rule_set_tp_dst(rule, value->be16);
 941         break;
 942
 943     case MFF_UDP_SRC:
 944         cls_rule_set_tp_src(rule, value->be16);
 945         break;
 946
 947     case MFF_UDP_DST:
 948         cls_rule_set_tp_dst(rule, value->be16);
 949         break;
 950
 951     case MFF_ICMP_TYPE:
 952         cls_rule_set_icmp_type(rule, value->u8);
 953         break;
 954
 955     case MFF_ICMP_CODE:
 956         cls_rule_set_icmp_code(rule, value->u8);
 957         break;
 958
 959     case MFF_ND_TARGET:
 960         cls_rule_set_nd_target(rule, &value->ipv6);
 961         break;
 962
 963     case MFF_N_IDS:
 964     default:
 965         NOT_REACHED();
 966     }
 967 }
 968
 969 /* Makes 'rule' wildcard field 'mf'.
 970  *
 971  * The caller is responsible for ensuring that 'rule' meets 'mf''s
 972  * prerequisites. */
 973 void
 974 mf_set_wild(const struct mf_field *mf, struct cls_rule *rule)
 975 {
 976     switch (mf->id) {
 977     case MFF_TUN_ID:
 978         cls_rule_set_tun_id_masked(rule, htonll(0), htonll(0));
 979         break;
 980
 981     case MFF_IN_PORT:
 982         rule->wc.wildcards |= FWW_IN_PORT;
 983         rule->flow.in_port = 0;
 984         break;
 985
 986 #if FLOW_N_REGS > 0
 987     case MFF_REG0:
 988         cls_rule_set_reg_masked(rule, 0, 0, 0);
 989         break;
 990 #endif
 991 #if FLOW_N_REGS > 1
 992     case MFF_REG1:
 993         cls_rule_set_reg_masked(rule, 1, 0, 0);
 994         break;
 995 #endif
 996 #if FLOW_N_REGS > 2
 997     case MFF_REG2:
 998         cls_rule_set_reg_masked(rule, 2, 0, 0);
 999         break;
1000 #endif
1001 #if FLOW_N_REGS > 3
1002     case MFF_REG3:
1003         cls_rule_set_reg_masked(rule, 3, 0, 0);
1004         break;
1005 #endif
1006 #if FLOW_N_REGS > 4
1007     case MFF_REG4:
1008         cls_rule_set_reg_masked(rule, 4, 0, 0);
1009         break;
1010 #endif
1011 #if FLOW_N_REGS > 5
1012 #error
1013 #endif
1014
1015     case MFF_ETH_SRC:
1016         rule->wc.wildcards |= FWW_DL_SRC;
1017         memset(rule->flow.dl_src, 0, sizeof rule->flow.dl_src);
1018         break;
1019
1020     case MFF_ETH_DST:
1021         rule->wc.wildcards |= FWW_DL_DST | FWW_ETH_MCAST;
1022         memset(rule->flow.dl_dst, 0, sizeof rule->flow.dl_dst);
1023         break;
1024
1025     case MFF_ETH_TYPE:
1026         rule->wc.wildcards |= FWW_DL_TYPE;
1027         rule->flow.dl_type = htons(0);
1028         break;
1029
1030     case MFF_VLAN_TCI:
1031         cls_rule_set_dl_tci_masked(rule, htons(0), htons(0));
1032         break;
1033
1034     case MFF_VLAN_VID:
1035         cls_rule_set_any_vid(rule);
1036         break;
1037
1038     case MFF_VLAN_PCP:
1039         cls_rule_set_any_pcp(rule);
1040         break;
1041
1042     case MFF_IPV4_SRC:
1043     case MFF_ARP_SPA:
1044         cls_rule_set_nw_src_masked(rule, htonl(0), htonl(0));
1045         break;
1046
1047     case MFF_IPV4_DST:
1048     case MFF_ARP_TPA:
1049         cls_rule_set_nw_dst_masked(rule, htonl(0), htonl(0));
1050         break;
1051
1052     case MFF_IPV6_SRC:
1053         memset(&rule->wc.ipv6_src_mask, 0, sizeof rule->wc.ipv6_src_mask);
1054         memset(&rule->flow.ipv6_src, 0, sizeof rule->flow.ipv6_src);
1055         break;
1056
1057     case MFF_IPV6_DST:
1058         memset(&rule->wc.ipv6_dst_mask, 0, sizeof rule->wc.ipv6_dst_mask);
1059         memset(&rule->flow.ipv6_dst, 0, sizeof rule->flow.ipv6_dst);
1060         break;
1061
1062     case MFF_IP_PROTO:
1063         rule->wc.wildcards |= FWW_NW_PROTO;
1064         rule->flow.nw_proto = 0;
1065         break;
1066
1067     case MFF_IP_TOS:
1068         rule->wc.wildcards |= FWW_NW_TOS;
1069         rule->flow.nw_tos = 0;
1070         break;
1071
1072     case MFF_ARP_OP:
1073         rule->wc.wildcards |= FWW_NW_PROTO;
1074         rule->flow.nw_proto = 0;
1075         break;
1076
1077     case MFF_ARP_SHA:
1078     case MFF_ND_SLL:
1079         rule->wc.wildcards |= FWW_ARP_SHA;
1080         memset(rule->flow.arp_sha, 0, sizeof rule->flow.arp_sha);
1081         break;
1082
1083     case MFF_ARP_THA:
1084     case MFF_ND_TLL:
1085         rule->wc.wildcards |= FWW_ARP_THA;
1086         memset(rule->flow.arp_tha, 0, sizeof rule->flow.arp_tha);
1087         break;
1088
1089     case MFF_TCP_SRC:
1090     case MFF_UDP_SRC:
1091     case MFF_ICMP_TYPE:
1092         rule->wc.wildcards |= FWW_TP_SRC;
1093         rule->flow.tp_src = htons(0);
1094         break;
1095
1096     case MFF_TCP_DST:
1097     case MFF_UDP_DST:
1098     case MFF_ICMP_CODE:
1099         rule->wc.wildcards |= FWW_TP_DST;
1100         rule->flow.tp_dst = htons(0);
1101         break;
1102
1103     case MFF_ND_TARGET:
1104         rule->wc.wildcards |= FWW_ND_TARGET;
1105         memset(&rule->flow.nd_target, 0, sizeof rule->flow.nd_target);
1106         break;
1107
1108     case MFF_N_IDS:
1109     default:
1110         NOT_REACHED();
1111     }
1112 }
1113
1114 /* Makes 'rule' match field 'mf' with the specified 'value' and 'mask'.
1115  * 'value' specifies a value to match and 'mask' specifies a wildcard pattern,
1116  * with a 1-bit indicating that the corresponding value bit must match and a
1117  * 0-bit indicating a don't-care.
1118  *
1119  * If 'mask' is NULL or points to all-1-bits, then this call is equivalent to
1120  * mf_set_value(mf, value, rule).  If 'mask' points to all-0-bits, then this
1121  * call is equivalent to mf_set_wild(mf, rule).
1122  *
1123  * 'mask' must be a valid mask for 'mf' (see mf_is_mask_valid()).  The caller
1124  * is responsible for ensuring that 'rule' meets 'mf''s prerequisites. */
1125 void
1126 mf_set(const struct mf_field *mf,
1127        const union mf_value *value, const union mf_value *mask,
1128        struct cls_rule *rule)
1129 {
1130     if (!mask || is_all_ones((const uint8_t *) mask, mf->n_bytes)) {
1131         mf_set_value(mf, value, rule);
1132         return;
1133     } else if (is_all_zeros((const uint8_t *) mask, mf->n_bytes)) {
1134         mf_set_wild(mf, rule);
1135         return;
1136     }
1137
1138     switch (mf->id) {
1139     case MFF_IN_PORT:
1140     case MFF_ETH_SRC:
1141     case MFF_ETH_TYPE:
1142     case MFF_VLAN_VID:
1143     case MFF_VLAN_PCP:
1144     case MFF_IP_PROTO:
1145     case MFF_IP_TOS:
1146     case MFF_ARP_OP:
1147     case MFF_ARP_SHA:
1148     case MFF_ARP_THA:
1149     case MFF_TCP_SRC:
1150     case MFF_TCP_DST:
1151     case MFF_UDP_SRC:
1152     case MFF_UDP_DST:
1153     case MFF_ICMP_TYPE:
1154     case MFF_ICMP_CODE:
1155     case MFF_ND_TARGET:
1156     case MFF_ND_SLL:
1157     case MFF_ND_TLL:
1158         NOT_REACHED();
1159
1160     case MFF_TUN_ID:
1161         cls_rule_set_tun_id_masked(rule, value->be64, mask->be64);
1162         break;
1163
1164 #if FLOW_N_REGS > 0
1165     case MFF_REG0:
1166 #endif
1167 #if FLOW_N_REGS > 1
1168     case MFF_REG1:
1169 #endif
1170 #if FLOW_N_REGS > 2
1171     case MFF_REG2:
1172 #endif
1173 #if FLOW_N_REGS > 3
1174     case MFF_REG3:
1175 #endif
1176 #if FLOW_N_REGS > 4
1177     case MFF_REG4:
1178 #endif
1179 #if FLOW_N_REGS > 5
1180 #error
1181 #endif
1182         cls_rule_set_reg_masked(rule, mf->id - MFF_REG0,
1183                                 ntohl(value->be32), ntohl(mask->be32));
1184         break;
1185
1186     case MFF_ETH_DST:
1187         if (flow_wildcards_is_dl_dst_mask_valid(mask->mac)) {
1188             cls_rule_set_dl_dst_masked(rule, value->mac, mask->mac);
1189         }
1190         break;
1191
1192     case MFF_VLAN_TCI:
1193         cls_rule_set_dl_tci_masked(rule, value->be16, mask->be16);
1194         break;
1195
1196     case MFF_IPV4_SRC:
1197         cls_rule_set_nw_src_masked(rule, value->be32, mask->be32);
1198         break;
1199
1200     case MFF_IPV4_DST:
1201         cls_rule_set_nw_dst_masked(rule, value->be32, mask->be32);
1202         break;
1203
1204     case MFF_IPV6_SRC:
1205         cls_rule_set_ipv6_src_masked(rule, &value->ipv6, &mask->ipv6);
1206         break;
1207
1208     case MFF_IPV6_DST:
1209         cls_rule_set_ipv6_dst_masked(rule, &value->ipv6, &mask->ipv6);
1210         break;
1211
1212     case MFF_ARP_SPA:
1213         cls_rule_set_nw_src_masked(rule, value->be32, mask->be32);
1214         break;
1215
1216     case MFF_ARP_TPA:
1217         cls_rule_set_nw_dst_masked(rule, value->be32, mask->be32);
1218         break;
1219
1220     case MFF_N_IDS:
1221     default:
1222         NOT_REACHED();
1223     }
1224 }
1225
1226 /* Makes a subfield starting at bit offset 'ofs' and continuing for 'n_bits' in
1227  * 'rule''s field 'mf' exactly match the 'n_bits' least-significant bits of
1228  * 'x'.
1229  *
1230  * Example: suppose that 'mf' is originally the following 2-byte field in
1231  * 'rule':
1232  *
1233  *     value == 0xe00a == 2#1110000000001010
1234  *      mask == 0xfc3f == 2#1111110000111111
1235  *
1236  * The call mf_set_subfield(mf, 0x55, 8, 7, rule) would have the following
1237  * effect (note that 0x55 is 2#1010101):
1238  *
1239  *     value == 0xd50a == 2#1101010100001010
1240  *      mask == 0xff3f == 2#1111111100111111
1241  *
1242  * The caller is responsible for ensuring that the result will be a valid
1243  * wildcard pattern for 'mf'.  The caller is responsible for ensuring that
1244  * 'rule' meets 'mf''s prerequisites. */
1245 void
1246 mf_set_subfield(const struct mf_field *mf, uint64_t x, unsigned int ofs,
1247                 unsigned int n_bits, struct cls_rule *rule)
1248 {
1249     if (ofs == 0 && mf->n_bytes * 8 == n_bits) {
1250         union mf_value value;
1251         int i;
1252
1253         for (i = mf->n_bytes - 1; i >= 0; i--) {
1254             ((uint8_t *) &value)[i] = x;
1255             x >>= 8;
1256         }
1257         mf_set_value(mf, &value, rule);
1258     } else {
1259         union mf_value value, mask;
1260         uint8_t *vp, *mp;
1261         unsigned int byte_ofs;
1262
1263         mf_get(mf, rule, &value, &mask);
1264
1265         byte_ofs = mf->n_bytes - ofs / 8;
1266         vp = &((uint8_t *) &value)[byte_ofs];
1267         mp = &((uint8_t *) &mask)[byte_ofs];
1268         if (ofs % 8) {
1269             unsigned int chunk = MIN(8 - ofs % 8, n_bits);
1270             uint8_t chunk_mask = ((1 << chunk) - 1) << (ofs % 8);
1271
1272             *--vp &= ~chunk_mask;
1273             *vp   |= chunk_mask & (x << (ofs % 8));
1274             *--mp |= chunk_mask;
1275
1276             x >>= chunk;
1277             n_bits -= chunk;
1278             ofs += chunk;
1279         }
1280         while (n_bits >= 8) {
1281             *--vp = x;
1282             *--mp = 0xff;
1283             x >>= 8;
1284             n_bits -= 8;
1285             ofs += 8;
1286         }
1287         if (n_bits) {
1288             uint8_t chunk_mask = (1 << n_bits) - 1;
1289
1290             *--vp &= ~chunk_mask;
1291             *vp   |= chunk_mask & x;
1292             *--mp |= chunk_mask;
1293         }
1294
1295         mf_set(mf, &value, &mask, rule);
1296     }
1297 }
1298
1299 /* Copies the value and wildcard bit pattern for 'mf' from 'rule' into the
1300  * 'value' and 'mask', respectively. */
1301 void
1302 mf_get(const struct mf_field *mf, const struct cls_rule *rule,
1303        union mf_value *value, union mf_value *mask)
1304 {
1305     mf_get_value(mf, &rule->flow, value);
1306     mf_get_mask(mf, &rule->wc, mask);
1307 }
1308
1309 /* Assigns a random value for field 'mf' to 'value'. */
1310 void
1311 mf_random_value(const struct mf_field *mf, union mf_value *value)
1312 {
1313     random_bytes(value, mf->n_bytes);
1314
1315     switch (mf->id) {
1316     case MFF_TUN_ID:
1317     case MFF_IN_PORT:
1318 #if FLOW_N_REGS > 0
1319     case MFF_REG0:
1320 #endif
1321 #if FLOW_N_REGS > 1
1322     case MFF_REG1:
1323 #endif
1324 #if FLOW_N_REGS > 2
1325     case MFF_REG2:
1326 #endif
1327 #if FLOW_N_REGS > 3
1328     case MFF_REG3:
1329 #endif
1330 #if FLOW_N_REGS > 4
1331     case MFF_REG4:
1332 #endif
1333 #if FLOW_N_REGS > 5
1334 #error
1335 #endif
1336     case MFF_ETH_SRC:
1337     case MFF_ETH_DST:
1338     case MFF_ETH_TYPE:
1339     case MFF_VLAN_TCI:
1340     case MFF_IPV4_SRC:
1341     case MFF_IPV4_DST:
1342     case MFF_IPV6_SRC:
1343     case MFF_IPV6_DST:
1344     case MFF_IP_PROTO:
1345     case MFF_ARP_SPA:
1346     case MFF_ARP_TPA:
1347     case MFF_ARP_SHA:
1348     case MFF_ARP_THA:
1349     case MFF_TCP_SRC:
1350     case MFF_TCP_DST:
1351     case MFF_UDP_SRC:
1352     case MFF_UDP_DST:
1353     case MFF_ICMP_TYPE:
1354     case MFF_ICMP_CODE:
1355     case MFF_ND_TARGET:
1356     case MFF_ND_SLL:
1357     case MFF_ND_TLL:
1358         break;
1359
1360     case MFF_IP_TOS:
1361         value->u8 &= ~0x03;
1362         break;
1363
1364     case MFF_ARP_OP:
1365         value->be16 &= htons(0xff);
1366         break;
1367
1368     case MFF_VLAN_VID:
1369         value->be16 &= htons(VLAN_VID_MASK);
1370         break;
1371
1372     case MFF_VLAN_PCP:
1373         value->u8 &= 0x07;
1374         break;
1375
1376     case MFF_N_IDS:
1377     default:
1378         NOT_REACHED();
1379     }
1380 }
1381
1382 static char *
1383 mf_from_integer_string(const struct mf_field *mf, const char *s,
1384                        uint8_t *valuep, uint8_t *maskp)
1385 {
1386     unsigned long long int integer, mask;
1387     char *tail;
1388     int i;
1389
1390     errno = 0;
1391     integer = strtoull(s, &tail, 0);
1392     if (errno || (*tail != '\0' && *tail != '/')) {
1393         goto syntax_error;
1394     }
1395
1396     if (*tail == '/') {
1397         mask = strtoull(tail + 1, &tail, 0);
1398         if (errno || *tail != '\0') {
1399             goto syntax_error;
1400         }
1401     } else {
1402         mask = ULLONG_MAX;
1403     }
1404
1405     for (i = mf->n_bytes - 1; i >= 0; i--) {
1406         valuep[i] = integer;
1407         maskp[i] = mask;
1408         integer >>= 8;
1409         mask >>= 8;
1410     }
1411     if (integer) {
1412         return xasprintf("%s: value too large for %u-byte field %s",
1413                          s, mf->n_bytes, mf->name);
1414     }
1415     return NULL;
1416
1417 syntax_error:
1418     return xasprintf("%s: bad syntax for %s", s, mf->name);
1419 }
1420
1421 static char *
1422 mf_from_ethernet_string(const struct mf_field *mf, const char *s,
1423                         uint8_t mac[ETH_ADDR_LEN],
1424                         uint8_t mask[ETH_ADDR_LEN])
1425 {
1426     assert(mf->n_bytes == ETH_ADDR_LEN);
1427
1428     switch (sscanf(s, ETH_ADDR_SCAN_FMT"/"ETH_ADDR_SCAN_FMT,
1429                    ETH_ADDR_SCAN_ARGS(mac), ETH_ADDR_SCAN_ARGS(mask))){
1430     case ETH_ADDR_SCAN_COUNT * 2:
1431         return NULL;
1432
1433     case ETH_ADDR_SCAN_COUNT:
1434         memset(mask, 0xff, ETH_ADDR_LEN);
1435         return NULL;
1436
1437     default:
1438         return xasprintf("%s: invalid Ethernet address", s);
1439     }
1440 }
1441
1442 static char *
1443 mf_from_ipv4_string(const struct mf_field *mf, const char *s,
1444                     ovs_be32 *ip, ovs_be32 *mask)
1445 {
1446     int prefix;
1447
1448     assert(mf->n_bytes == sizeof *ip);
1449
1450     if (sscanf(s, IP_SCAN_FMT"/"IP_SCAN_FMT,
1451                IP_SCAN_ARGS(ip), IP_SCAN_ARGS(mask)) == IP_SCAN_COUNT * 2) {
1452         /* OK. */
1453     } else if (sscanf(s, IP_SCAN_FMT"/%d",
1454                       IP_SCAN_ARGS(ip), &prefix) == IP_SCAN_COUNT + 1) {
1455         if (prefix <= 0 || prefix > 32) {
1456             return xasprintf("%s: network prefix bits not between 1 and "
1457                              "32", s);
1458         } else if (prefix == 32) {
1459             *mask = htonl(UINT32_MAX);
1460         } else {
1461             *mask = htonl(((1u << prefix) - 1) << (32 - prefix));
1462         }
1463     } else if (sscanf(s, IP_SCAN_FMT, IP_SCAN_ARGS(ip)) == IP_SCAN_COUNT) {
1464         *mask = htonl(UINT32_MAX);
1465     } else {
1466         return xasprintf("%s: invalid IP address", s);
1467     }
1468     return NULL;
1469 }
1470
1471 static char *
1472 mf_from_ipv6_string(const struct mf_field *mf, const char *s,
1473                     struct in6_addr *value, struct in6_addr *mask)
1474 {
1475     char *str = xstrdup(s);
1476     char *save_ptr = NULL;
1477     const char *name, *netmask;
1478     int retval;
1479
1480     assert(mf->n_bytes == sizeof *value);
1481
1482     name = strtok_r(str, "/", &save_ptr);
1483     retval = name ? lookup_ipv6(name, value) : EINVAL;
1484     if (retval) {
1485         char *err;
1486
1487         err = xasprintf("%s: could not convert to IPv6 address", str);
1488         free(str);
1489
1490         return err;
1491     }
1492
1493     netmask = strtok_r(NULL, "/", &save_ptr);
1494     if (netmask) {
1495         int prefix = atoi(netmask);
1496         if (prefix <= 0 || prefix > 128) {
1497             free(str);
1498             return xasprintf("%s: prefix bits not between 1 and 128", s);
1499         } else {
1500             *mask = ipv6_create_mask(prefix);
1501         }
1502     } else {
1503         *mask = in6addr_exact;
1504     }
1505     free(str);
1506
1507     return NULL;
1508 }
1509
1510 static char *
1511 mf_from_ofp_port_string(const struct mf_field *mf, const char *s,
1512                         ovs_be16 *valuep, ovs_be16 *maskp)
1513 {
1514     uint16_t port;
1515
1516     assert(mf->n_bytes == sizeof(ovs_be16));
1517     if (ofputil_port_from_string(s, &port)) {
1518         *valuep = htons(port);
1519         *maskp = htons(UINT16_MAX);
1520         return NULL;
1521     } else {
1522         return mf_from_integer_string(mf, s,
1523                                       (uint8_t *) valuep, (uint8_t *) maskp);
1524     }
1525 }
1526
1527 /* Parses 's', a string value for field 'mf', into 'value' and 'mask'.  Returns
1528  * NULL if successful, otherwise a malloc()'d string describing the error. */
1529 char *
1530 mf_parse(const struct mf_field *mf, const char *s,
1531          union mf_value *value, union mf_value *mask)
1532 {
1533     if (!strcasecmp(s, "any") || !strcmp(s, "*")) {
1534         memset(value, 0, mf->n_bytes);
1535         memset(mask, 0, mf->n_bytes);
1536         return NULL;
1537     }
1538
1539     switch (mf->string) {
1540     case MFS_DECIMAL:
1541     case MFS_HEXADECIMAL:
1542         return mf_from_integer_string(mf, s,
1543                                       (uint8_t *) value, (uint8_t *) mask);
1544
1545     case MFS_ETHERNET:
1546         return mf_from_ethernet_string(mf, s, value->mac, mask->mac);
1547
1548     case MFS_IPV4:
1549         return mf_from_ipv4_string(mf, s, &value->be32, &mask->be32);
1550
1551     case MFS_IPV6:
1552         return mf_from_ipv6_string(mf, s, &value->ipv6, &mask->ipv6);
1553
1554     case MFS_OFP_PORT:
1555         return mf_from_ofp_port_string(mf, s, &value->be16, &mask->be16);
1556     }
1557     NOT_REACHED();
1558 }
1559
1560 /* Parses 's', a string value for field 'mf', into 'value'.  Returns NULL if
1561  * successful, otherwise a malloc()'d string describing the error. */
1562 char *
1563 mf_parse_value(const struct mf_field *mf, const char *s, union mf_value *value)
1564 {
1565     union mf_value mask;
1566     char *error;
1567
1568     error = mf_parse(mf, s, value, &mask);
1569     if (error) {
1570         return error;
1571     }
1572
1573     if (!is_all_ones((const uint8_t *) &mask, mf->n_bytes)) {
1574         return xasprintf("%s: wildcards not allowed here", s);
1575     }
1576     return NULL;
1577 }
1578
1579 static void
1580 mf_format_integer_string(const struct mf_field *mf, const uint8_t *valuep,
1581                          const uint8_t *maskp, struct ds *s)
1582 {
1583     unsigned long long int integer;
1584     int i;
1585
1586     assert(mf->n_bytes <= 8);
1587
1588     integer = 0;
1589     for (i = 0; i < mf->n_bytes; i++) {
1590         integer = (integer << 8) | valuep[i];
1591     }
1592     if (mf->string == MFS_HEXADECIMAL) {
1593         ds_put_format(s, "%#llx", integer);
1594     } else {
1595         ds_put_format(s, "%lld", integer);
1596     }
1597
1598     if (maskp) {
1599         unsigned long long int mask;
1600
1601         mask = 0;
1602         for (i = 0; i < mf->n_bytes; i++) {
1603             mask = (mask << 8) | maskp[i];
1604         }
1605
1606         /* I guess we could write the mask in decimal for MFS_DECIMAL but I'm
1607          * not sure that that a bit-mask written in decimal is ever easier to
1608          * understand than the same bit-mask written in hexadecimal. */
1609         ds_put_format(s, "/%#llx", mask);
1610     }
1611 }
1612
1613 /* Appends to 's' a string representation of field 'mf' whose value is in
1614  * 'value' and 'mask'.  'mask' may be NULL to indicate an exact match. */
1615 void
1616 mf_format(const struct mf_field *mf,
1617           const union mf_value *value, const union mf_value *mask,
1618           struct ds *s)
1619 {
1620     if (mask) {
1621         if (is_all_zeros((const uint8_t *) mask, mf->n_bytes)) {
1622             ds_put_cstr(s, "ANY");
1623             return;
1624         } else if (is_all_ones((const uint8_t *) mask, mf->n_bytes)) {
1625             mask = NULL;
1626         }
1627     }
1628
1629     switch (mf->string) {
1630     case MFS_OFP_PORT:
1631         if (!mask) {
1632             ofputil_format_port(ntohs(value->be16), s);
1633             break;
1634         }
1635         /* fall through */
1636     case MFS_DECIMAL:
1637     case MFS_HEXADECIMAL:
1638         mf_format_integer_string(mf, (uint8_t *) value, (uint8_t *) mask, s);
1639         break;
1640
1641     case MFS_ETHERNET:
1642         ds_put_format(s, ETH_ADDR_FMT, ETH_ADDR_ARGS(value->mac));
1643         if (mask) {
1644             ds_put_format(s, "/"ETH_ADDR_FMT, ETH_ADDR_ARGS(mask->mac));
1645         }
1646         break;
1647
1648     case MFS_IPV4:
1649         ip_format_masked(value->be32, mask ? mask->be32 : htonl(UINT32_MAX),
1650                          s);
1651         break;
1652
1653     case MFS_IPV6:
1654         print_ipv6_masked(s, &value->ipv6, mask ? &mask->ipv6 : NULL);
1655         break;
1656
1657     default:
1658         NOT_REACHED();
1659     }
1660 }