lib/packets.h

   1 /*
   2  * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 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 #ifndef PACKETS_H
  18 #define PACKETS_H 1
  19
  20 #include <inttypes.h>
  21 #include <sys/types.h>
  22 #include <netinet/in.h>
  23 #include <stdint.h>
  24 #include <string.h>
  25 #include "compiler.h"
  26 #include "flow.h"
  27 #include "openvswitch/types.h"
  28 #include "random.h"
  29 #include "util.h"
  30
  31 struct ofpbuf;
  32 struct ds;
  33
  34 bool dpid_from_string(const char *s, uint64_t *dpidp);
  35
  36 #define ETH_ADDR_LEN           6
  37
  38 static const uint8_t eth_addr_broadcast[ETH_ADDR_LEN] OVS_UNUSED
  39     = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
  40
  41 static const uint8_t eth_addr_stp[ETH_ADDR_LEN] OVS_UNUSED
  42     = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x00 };
  43
  44 static const uint8_t eth_addr_lacp[ETH_ADDR_LEN] OVS_UNUSED
  45     = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x02 };
  46
  47 static const uint8_t eth_addr_bfd[ETH_ADDR_LEN] OVS_UNUSED
  48     = { 0x00, 0x23, 0x20, 0x00, 0x00, 0x01 };
  49
  50 static inline bool eth_addr_is_broadcast(const uint8_t ea[6])
  51 {
  52     return (ea[0] & ea[1] & ea[2] & ea[3] & ea[4] & ea[5]) == 0xff;
  53 }
  54
  55 static inline bool eth_addr_is_multicast(const uint8_t ea[6])
  56 {
  57     return ea[0] & 1;
  58 }
  59 static inline bool eth_addr_is_local(const uint8_t ea[6])
  60 {
  61     /* Local if it is either a locally administered address or a Nicira random
  62      * address. */
  63     return ea[0] & 2
  64        || (ea[0] == 0x00 && ea[1] == 0x23 && ea[2] == 0x20 && ea[3] & 0x80);
  65 }
  66 static inline bool eth_addr_is_zero(const uint8_t ea[6])
  67 {
  68     return !(ea[0] | ea[1] | ea[2] | ea[3] | ea[4] | ea[5]);
  69 }
  70
  71 static inline int eth_mask_is_exact(const uint8_t ea[ETH_ADDR_LEN])
  72 {
  73     return (ea[0] & ea[1] & ea[2] & ea[3] & ea[4] & ea[5]) == 0xff;
  74 }
  75
  76 static inline int eth_addr_compare_3way(const uint8_t a[ETH_ADDR_LEN],
  77                                         const uint8_t b[ETH_ADDR_LEN])
  78 {
  79     return memcmp(a, b, ETH_ADDR_LEN);
  80 }
  81 static inline bool eth_addr_equals(const uint8_t a[ETH_ADDR_LEN],
  82                                    const uint8_t b[ETH_ADDR_LEN])
  83 {
  84     return !eth_addr_compare_3way(a, b);
  85 }
  86 static inline bool eth_addr_equal_except(const uint8_t a[ETH_ADDR_LEN],
  87                                     const uint8_t b[ETH_ADDR_LEN],
  88                                     const uint8_t mask[ETH_ADDR_LEN])
  89 {
  90     return !(((a[0] ^ b[0]) & mask[0])
  91              || ((a[1] ^ b[1]) & mask[1])
  92              || ((a[2] ^ b[2]) & mask[2])
  93              || ((a[3] ^ b[3]) & mask[3])
  94              || ((a[4] ^ b[4]) & mask[4])
  95              || ((a[5] ^ b[5]) & mask[5]));
  96 }
  97 static inline uint64_t eth_addr_to_uint64(const uint8_t ea[ETH_ADDR_LEN])
  98 {
  99     return (((uint64_t) ea[0] << 40)
 100             | ((uint64_t) ea[1] << 32)
 101             | ((uint64_t) ea[2] << 24)
 102             | ((uint64_t) ea[3] << 16)
 103             | ((uint64_t) ea[4] << 8)
 104             | ea[5]);
 105 }
 106 static inline void eth_addr_from_uint64(uint64_t x, uint8_t ea[ETH_ADDR_LEN])
 107 {
 108     ea[0] = x >> 40;
 109     ea[1] = x >> 32;
 110     ea[2] = x >> 24;
 111     ea[3] = x >> 16;
 112     ea[4] = x >> 8;
 113     ea[5] = x;
 114 }
 115 static inline void eth_addr_mark_random(uint8_t ea[ETH_ADDR_LEN])
 116 {
 117     ea[0] &= ~1;                /* Unicast. */
 118     ea[0] |= 2;                 /* Private. */
 119 }
 120 static inline void eth_addr_random(uint8_t ea[ETH_ADDR_LEN])
 121 {
 122     random_bytes(ea, ETH_ADDR_LEN);
 123     eth_addr_mark_random(ea);
 124 }
 125 static inline void eth_addr_nicira_random(uint8_t ea[ETH_ADDR_LEN])
 126 {
 127     eth_addr_random(ea);
 128
 129     /* Set the OUI to the Nicira one. */
 130     ea[0] = 0x00;
 131     ea[1] = 0x23;
 132     ea[2] = 0x20;
 133
 134     /* Set the top bit to indicate random Nicira address. */
 135     ea[3] |= 0x80;
 136 }
 137
 138 bool eth_addr_is_reserved(const uint8_t ea[ETH_ADDR_LEN]);
 139 bool eth_addr_from_string(const char *, uint8_t ea[ETH_ADDR_LEN]);
 140
 141 void compose_rarp(struct ofpbuf *, const uint8_t eth_src[ETH_ADDR_LEN]);
 142
 143 void eth_push_vlan(struct ofpbuf *, ovs_be16 tci);
 144 void eth_pop_vlan(struct ofpbuf *);
 145
 146 uint16_t eth_mpls_depth(const struct ofpbuf *packet);
 147
 148 void set_ethertype(struct ofpbuf *packet, ovs_be16 eth_type);
 149
 150 const char *eth_from_hex(const char *hex, struct ofpbuf **packetp);
 151 void eth_format_masked(const uint8_t eth[ETH_ADDR_LEN],
 152                        const uint8_t mask[ETH_ADDR_LEN], struct ds *s);
 153 void eth_addr_bitand(const uint8_t src[ETH_ADDR_LEN],
 154                      const uint8_t mask[ETH_ADDR_LEN],
 155                      uint8_t dst[ETH_ADDR_LEN]);
 156
 157 void set_mpls_lse(struct ofpbuf *, ovs_be32 label);
 158 void push_mpls(struct ofpbuf *packet, ovs_be16 ethtype, ovs_be32 lse);
 159 void pop_mpls(struct ofpbuf *, ovs_be16 ethtype);
 160
 161 void set_mpls_lse_ttl(ovs_be32 *lse, uint8_t ttl);
 162 void set_mpls_lse_tc(ovs_be32 *lse, uint8_t tc);
 163 void set_mpls_lse_label(ovs_be32 *lse, ovs_be32 label);
 164 void set_mpls_lse_bos(ovs_be32 *lse, uint8_t bos);
 165 ovs_be32 set_mpls_lse_values(uint8_t ttl, uint8_t tc, uint8_t bos,
 166                              ovs_be32 label);
 167
 168 /* Example:
 169  *
 170  * uint8_t mac[ETH_ADDR_LEN];
 171  *    [...]
 172  * printf("The Ethernet address is "ETH_ADDR_FMT"\n", ETH_ADDR_ARGS(mac));
 173  *
 174  */
 175 #define ETH_ADDR_FMT                                                    \
 176     "%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8
 177 #define ETH_ADDR_ARGS(ea)                                   \
 178     (ea)[0], (ea)[1], (ea)[2], (ea)[3], (ea)[4], (ea)[5]
 179
 180 /* Example:
 181  *
 182  * char *string = "1 00:11:22:33:44:55 2";
 183  * uint8_t mac[ETH_ADDR_LEN];
 184  * int a, b;
 185  *
 186  * if (sscanf(string, "%d"ETH_ADDR_SCAN_FMT"%d",
 187  *     &a, ETH_ADDR_SCAN_ARGS(mac), &b) == 1 + ETH_ADDR_SCAN_COUNT + 1) {
 188  *     ...
 189  * }
 190  */
 191 #define ETH_ADDR_SCAN_FMT "%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8
 192 #define ETH_ADDR_SCAN_ARGS(ea) \
 193         &(ea)[0], &(ea)[1], &(ea)[2], &(ea)[3], &(ea)[4], &(ea)[5]
 194 #define ETH_ADDR_SCAN_COUNT 6
 195
 196 #define ETH_TYPE_IP            0x0800
 197 #define ETH_TYPE_ARP           0x0806
 198 #define ETH_TYPE_VLAN_8021Q    0x8100
 199 #define ETH_TYPE_VLAN          ETH_TYPE_VLAN_8021Q
 200 #define ETH_TYPE_VLAN_8021AD   0x88a8
 201 #define ETH_TYPE_IPV6          0x86dd
 202 #define ETH_TYPE_LACP          0x8809
 203 #define ETH_TYPE_RARP          0x8035
 204 #define ETH_TYPE_MPLS          0x8847
 205 #define ETH_TYPE_MPLS_MCAST    0x8848
 206
 207 static inline bool eth_type_mpls(ovs_be16 eth_type)
 208 {
 209     return eth_type == htons(ETH_TYPE_MPLS) ||
 210         eth_type == htons(ETH_TYPE_MPLS_MCAST);
 211 }
 212
 213 /* Minimum value for an Ethernet type.  Values below this are IEEE 802.2 frame
 214  * lengths. */
 215 #define ETH_TYPE_MIN           0x600
 216
 217 #define ETH_HEADER_LEN 14
 218 #define ETH_PAYLOAD_MIN 46
 219 #define ETH_PAYLOAD_MAX 1500
 220 #define ETH_TOTAL_MIN (ETH_HEADER_LEN + ETH_PAYLOAD_MIN)
 221 #define ETH_TOTAL_MAX (ETH_HEADER_LEN + ETH_PAYLOAD_MAX)
 222 #define ETH_VLAN_TOTAL_MAX (ETH_HEADER_LEN + VLAN_HEADER_LEN + ETH_PAYLOAD_MAX)
 223 OVS_PACKED(
 224 struct eth_header {
 225     uint8_t eth_dst[ETH_ADDR_LEN];
 226     uint8_t eth_src[ETH_ADDR_LEN];
 227     ovs_be16 eth_type;
 228 });
 229 BUILD_ASSERT_DECL(ETH_HEADER_LEN == sizeof(struct eth_header));
 230
 231 #define LLC_DSAP_SNAP 0xaa
 232 #define LLC_SSAP_SNAP 0xaa
 233 #define LLC_CNTL_SNAP 3
 234
 235 #define LLC_HEADER_LEN 3
 236 OVS_PACKED(
 237 struct llc_header {
 238     uint8_t llc_dsap;
 239     uint8_t llc_ssap;
 240     uint8_t llc_cntl;
 241 });
 242 BUILD_ASSERT_DECL(LLC_HEADER_LEN == sizeof(struct llc_header));
 243
 244 #define SNAP_ORG_ETHERNET "\0\0" /* The compiler adds a null byte, so
 245                                     sizeof(SNAP_ORG_ETHERNET) == 3. */
 246 #define SNAP_HEADER_LEN 5
 247 OVS_PACKED(
 248 struct snap_header {
 249     uint8_t snap_org[3];
 250     ovs_be16 snap_type;
 251 });
 252 BUILD_ASSERT_DECL(SNAP_HEADER_LEN == sizeof(struct snap_header));
 253
 254 #define LLC_SNAP_HEADER_LEN (LLC_HEADER_LEN + SNAP_HEADER_LEN)
 255 OVS_PACKED(
 256 struct llc_snap_header {
 257     struct llc_header llc;
 258     struct snap_header snap;
 259 });
 260 BUILD_ASSERT_DECL(LLC_SNAP_HEADER_LEN == sizeof(struct llc_snap_header));
 261
 262 #define VLAN_VID_MASK 0x0fff
 263 #define VLAN_VID_SHIFT 0
 264
 265 #define VLAN_PCP_MASK 0xe000
 266 #define VLAN_PCP_SHIFT 13
 267
 268 #define VLAN_CFI 0x1000
 269 #define VLAN_CFI_SHIFT 12
 270
 271 /* Given the vlan_tci field from an 802.1Q header, in network byte order,
 272  * returns the VLAN ID in host byte order. */
 273 static inline uint16_t
 274 vlan_tci_to_vid(ovs_be16 vlan_tci)
 275 {
 276     return (ntohs(vlan_tci) & VLAN_VID_MASK) >> VLAN_VID_SHIFT;
 277 }
 278
 279 /* Given the vlan_tci field from an 802.1Q header, in network byte order,
 280  * returns the priority code point (PCP) in host byte order. */
 281 static inline int
 282 vlan_tci_to_pcp(ovs_be16 vlan_tci)
 283 {
 284     return (ntohs(vlan_tci) & VLAN_PCP_MASK) >> VLAN_PCP_SHIFT;
 285 }
 286
 287 /* Given the vlan_tci field from an 802.1Q header, in network byte order,
 288  * returns the Canonical Format Indicator (CFI). */
 289 static inline int
 290 vlan_tci_to_cfi(ovs_be16 vlan_tci)
 291 {
 292     return (vlan_tci & htons(VLAN_CFI)) != 0;
 293 }
 294
 295 #define VLAN_HEADER_LEN 4
 296 struct vlan_header {
 297     ovs_be16 vlan_tci;          /* Lowest 12 bits are VLAN ID. */
 298     ovs_be16 vlan_next_type;
 299 };
 300 BUILD_ASSERT_DECL(VLAN_HEADER_LEN == sizeof(struct vlan_header));
 301
 302 #define VLAN_ETH_HEADER_LEN (ETH_HEADER_LEN + VLAN_HEADER_LEN)
 303 OVS_PACKED(
 304 struct vlan_eth_header {
 305     uint8_t veth_dst[ETH_ADDR_LEN];
 306     uint8_t veth_src[ETH_ADDR_LEN];
 307     ovs_be16 veth_type;         /* Always htons(ETH_TYPE_VLAN). */
 308     ovs_be16 veth_tci;          /* Lowest 12 bits are VLAN ID. */
 309     ovs_be16 veth_next_type;
 310 });
 311 BUILD_ASSERT_DECL(VLAN_ETH_HEADER_LEN == sizeof(struct vlan_eth_header));
 312
 313 /* MPLS related definitions */
 314 #define MPLS_TTL_MASK       0x000000ff
 315 #define MPLS_TTL_SHIFT      0
 316
 317 #define MPLS_BOS_MASK       0x00000100
 318 #define MPLS_BOS_SHIFT      8
 319
 320 #define MPLS_TC_MASK        0x00000e00
 321 #define MPLS_TC_SHIFT       9
 322
 323 #define MPLS_LABEL_MASK     0xfffff000
 324 #define MPLS_LABEL_SHIFT    12
 325
 326 #define MPLS_HLEN           4
 327
 328 struct mpls_hdr {
 329     ovs_be32 mpls_lse;
 330 };
 331 BUILD_ASSERT_DECL(MPLS_HLEN == sizeof(struct mpls_hdr));
 332
 333 /* Given a mpls label stack entry in network byte order
 334  * return mpls label in host byte order */
 335 static inline uint32_t
 336 mpls_lse_to_label(ovs_be32 mpls_lse)
 337 {
 338     return (ntohl(mpls_lse) & MPLS_LABEL_MASK) >> MPLS_LABEL_SHIFT;
 339 }
 340
 341 /* Given a mpls label stack entry in network byte order
 342  * return mpls tc */
 343 static inline uint8_t
 344 mpls_lse_to_tc(ovs_be32 mpls_lse)
 345 {
 346     return (ntohl(mpls_lse) & MPLS_TC_MASK) >> MPLS_TC_SHIFT;
 347 }
 348
 349 /* Given a mpls label stack entry in network byte order
 350  * return mpls ttl */
 351 static inline uint8_t
 352 mpls_lse_to_ttl(ovs_be32 mpls_lse)
 353 {
 354     return (ntohl(mpls_lse) & MPLS_TTL_MASK) >> MPLS_TTL_SHIFT;
 355 }
 356
 357 /* Set TTL in mpls lse. */
 358 static inline void
 359 flow_set_mpls_lse_ttl(ovs_be32 *mpls_lse, uint8_t ttl)
 360 {
 361     *mpls_lse &= ~htonl(MPLS_TTL_MASK);
 362     *mpls_lse |= htonl(ttl << MPLS_TTL_SHIFT);
 363 }
 364
 365 /* Given a mpls label stack entry in network byte order
 366  * return mpls BoS bit  */
 367 static inline uint8_t
 368 mpls_lse_to_bos(ovs_be32 mpls_lse)
 369 {
 370     return (mpls_lse & htonl(MPLS_BOS_MASK)) != 0;
 371 }
 372
 373 #define IP_FMT "%"PRIu32".%"PRIu32".%"PRIu32".%"PRIu32
 374 #define IP_ARGS(ip)                             \
 375     ntohl(ip) >> 24,                            \
 376     (ntohl(ip) >> 16) & 0xff,                   \
 377     (ntohl(ip) >> 8) & 0xff,                    \
 378     ntohl(ip) & 0xff
 379
 380 /* Example:
 381  *
 382  * char *string = "1 33.44.55.66 2";
 383  * ovs_be32 ip;
 384  * int a, b;
 385  *
 386  * if (sscanf(string, "%d"IP_SCAN_FMT"%d",
 387  *     &a, IP_SCAN_ARGS(&ip), &b) == 1 + IP_SCAN_COUNT + 1) {
 388  *     ...
 389  * }
 390  */
 391 #define IP_SCAN_FMT "%"SCNu8".%"SCNu8".%"SCNu8".%"SCNu8
 392 #define IP_SCAN_ARGS(ip)                                    \
 393         ((void) (ovs_be32) *(ip), &((uint8_t *) ip)[0]),    \
 394         &((uint8_t *) ip)[1],                               \
 395         &((uint8_t *) ip)[2],                               \
 396         &((uint8_t *) ip)[3]
 397 #define IP_SCAN_COUNT 4
 398
 399 /* Returns true if 'netmask' is a CIDR netmask, that is, if it consists of N
 400  * high-order 1-bits and 32-N low-order 0-bits. */
 401 static inline bool
 402 ip_is_cidr(ovs_be32 netmask)
 403 {
 404     uint32_t x = ~ntohl(netmask);
 405     return !(x & (x + 1));
 406 }
 407 static inline bool
 408 ip_is_multicast(ovs_be32 ip)
 409 {
 410     return (ip & htonl(0xf0000000)) == htonl(0xe0000000);
 411 }
 412 int ip_count_cidr_bits(ovs_be32 netmask);
 413 void ip_format_masked(ovs_be32 ip, ovs_be32 mask, struct ds *);
 414
 415 #define IP_VER(ip_ihl_ver) ((ip_ihl_ver) >> 4)
 416 #define IP_IHL(ip_ihl_ver) ((ip_ihl_ver) & 15)
 417 #define IP_IHL_VER(ihl, ver) (((ver) << 4) | (ihl))
 418
 419 #ifndef IPPROTO_SCTP
 420 #define IPPROTO_SCTP 132
 421 #endif
 422
 423 /* TOS fields. */
 424 #define IP_ECN_NOT_ECT 0x0
 425 #define IP_ECN_ECT_1 0x01
 426 #define IP_ECN_ECT_0 0x02
 427 #define IP_ECN_CE 0x03
 428 #define IP_ECN_MASK 0x03
 429 #define IP_DSCP_MASK 0xfc
 430
 431 #define IP_VERSION 4
 432
 433 #define IP_DONT_FRAGMENT  0x4000 /* Don't fragment. */
 434 #define IP_MORE_FRAGMENTS 0x2000 /* More fragments. */
 435 #define IP_FRAG_OFF_MASK  0x1fff /* Fragment offset. */
 436 #define IP_IS_FRAGMENT(ip_frag_off) \
 437         ((ip_frag_off) & htons(IP_MORE_FRAGMENTS | IP_FRAG_OFF_MASK))
 438
 439 #define IP_HEADER_LEN 20
 440 struct ip_header {
 441     uint8_t ip_ihl_ver;
 442     uint8_t ip_tos;
 443     ovs_be16 ip_tot_len;
 444     ovs_be16 ip_id;
 445     ovs_be16 ip_frag_off;
 446     uint8_t ip_ttl;
 447     uint8_t ip_proto;
 448     ovs_be16 ip_csum;
 449     ovs_be32 ip_src;
 450     ovs_be32 ip_dst;
 451 };
 452 BUILD_ASSERT_DECL(IP_HEADER_LEN == sizeof(struct ip_header));
 453
 454 #define ICMP_HEADER_LEN 8
 455 struct icmp_header {
 456     uint8_t icmp_type;
 457     uint8_t icmp_code;
 458     ovs_be16 icmp_csum;
 459     union {
 460         struct {
 461             ovs_be16 id;
 462             ovs_be16 seq;
 463         } echo;
 464         struct {
 465             ovs_be16 empty;
 466             ovs_be16 mtu;
 467         } frag;
 468         ovs_be32 gateway;
 469     } icmp_fields;
 470     uint8_t icmp_data[0];
 471 };
 472 BUILD_ASSERT_DECL(ICMP_HEADER_LEN == sizeof(struct icmp_header));
 473
 474 #define SCTP_HEADER_LEN 12
 475 struct sctp_header {
 476     ovs_be16 sctp_src;
 477     ovs_be16 sctp_dst;
 478     ovs_be32 sctp_vtag;
 479     ovs_be32 sctp_csum;
 480 };
 481 BUILD_ASSERT_DECL(SCTP_HEADER_LEN == sizeof(struct sctp_header));
 482
 483 #define UDP_HEADER_LEN 8
 484 struct udp_header {
 485     ovs_be16 udp_src;
 486     ovs_be16 udp_dst;
 487     ovs_be16 udp_len;
 488     ovs_be16 udp_csum;
 489 };
 490 BUILD_ASSERT_DECL(UDP_HEADER_LEN == sizeof(struct udp_header));
 491
 492 #define TCP_FIN 0x01
 493 #define TCP_SYN 0x02
 494 #define TCP_RST 0x04
 495 #define TCP_PSH 0x08
 496 #define TCP_ACK 0x10
 497 #define TCP_URG 0x20
 498
 499 #define TCP_CTL(flags, offset) (htons((flags) | ((offset) << 12)))
 500 #define TCP_FLAGS(tcp_ctl) (ntohs(tcp_ctl) & 0x003f)
 501 #define TCP_OFFSET(tcp_ctl) (ntohs(tcp_ctl) >> 12)
 502
 503 #define TCP_HEADER_LEN 20
 504 struct tcp_header {
 505     ovs_be16 tcp_src;
 506     ovs_be16 tcp_dst;
 507     ovs_be32 tcp_seq;
 508     ovs_be32 tcp_ack;
 509     ovs_be16 tcp_ctl;
 510     ovs_be16 tcp_winsz;
 511     ovs_be16 tcp_csum;
 512     ovs_be16 tcp_urg;
 513 };
 514 BUILD_ASSERT_DECL(TCP_HEADER_LEN == sizeof(struct tcp_header));
 515
 516 #define ARP_HRD_ETHERNET 1
 517 #define ARP_PRO_IP 0x0800
 518 #define ARP_OP_REQUEST 1
 519 #define ARP_OP_REPLY 2
 520 #define ARP_OP_RARP 3
 521
 522 #define ARP_ETH_HEADER_LEN 28
 523 OVS_PACKED(
 524 struct arp_eth_header {
 525     /* Generic members. */
 526     ovs_be16 ar_hrd;           /* Hardware type. */
 527     ovs_be16 ar_pro;           /* Protocol type. */
 528     uint8_t ar_hln;            /* Hardware address length. */
 529     uint8_t ar_pln;            /* Protocol address length. */
 530     ovs_be16 ar_op;            /* Opcode. */
 531
 532     /* Ethernet+IPv4 specific members. */
 533     uint8_t ar_sha[ETH_ADDR_LEN]; /* Sender hardware address. */
 534     ovs_be32 ar_spa;           /* Sender protocol address. */
 535     uint8_t ar_tha[ETH_ADDR_LEN]; /* Target hardware address. */
 536     ovs_be32 ar_tpa;           /* Target protocol address. */
 537 });
 538 BUILD_ASSERT_DECL(ARP_ETH_HEADER_LEN == sizeof(struct arp_eth_header));
 539
 540 /* The IPv6 flow label is in the lower 20 bits of the first 32-bit word. */
 541 #define IPV6_LABEL_MASK 0x000fffff
 542
 543 /* Example:
 544  *
 545  * char *string = "1 ::1 2";
 546  * char ipv6_s[IPV6_SCAN_LEN + 1];
 547  * struct in6_addr ipv6;
 548  *
 549  * if (sscanf(string, "%d"IPV6_SCAN_FMT"%d", &a, ipv6_s, &b) == 3
 550  *     && inet_pton(AF_INET6, ipv6_s, &ipv6) == 1) {
 551  *     ...
 552  * }
 553  */
 554 #define IPV6_SCAN_FMT "%46[0123456789abcdefABCDEF:.]"
 555 #define IPV6_SCAN_LEN 46
 556
 557 extern const struct in6_addr in6addr_exact;
 558 #define IN6ADDR_EXACT_INIT { { { 0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff, \
 559                                  0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff } } }
 560
 561 static inline bool ipv6_addr_equals(const struct in6_addr *a,
 562                                     const struct in6_addr *b)
 563 {
 564 #ifdef IN6_ARE_ADDR_EQUAL
 565     return IN6_ARE_ADDR_EQUAL(a, b);
 566 #else
 567     return !memcmp(a, b, sizeof(*a));
 568 #endif
 569 }
 570
 571 static inline bool ipv6_mask_is_any(const struct in6_addr *mask) {
 572     return ipv6_addr_equals(mask, &in6addr_any);
 573 }
 574
 575 static inline bool ipv6_mask_is_exact(const struct in6_addr *mask) {
 576     return ipv6_addr_equals(mask, &in6addr_exact);
 577 }
 578
 579 static inline bool dl_type_is_ip_any(ovs_be16 dl_type)
 580 {
 581     return dl_type == htons(ETH_TYPE_IP)
 582         || dl_type == htons(ETH_TYPE_IPV6);
 583 }
 584
 585 static inline bool is_ip_any(const struct flow *flow)
 586 {
 587     return dl_type_is_ip_any(flow->dl_type);
 588 }
 589
 590 void format_ipv6_addr(char *addr_str, const struct in6_addr *addr);
 591 void print_ipv6_addr(struct ds *string, const struct in6_addr *addr);
 592 void print_ipv6_masked(struct ds *string, const struct in6_addr *addr,
 593                        const struct in6_addr *mask);
 594 struct in6_addr ipv6_addr_bitand(const struct in6_addr *src,
 595                                  const struct in6_addr *mask);
 596 struct in6_addr ipv6_create_mask(int mask);
 597 int ipv6_count_cidr_bits(const struct in6_addr *netmask);
 598 bool ipv6_is_cidr(const struct in6_addr *netmask);
 599
 600 void *eth_compose(struct ofpbuf *, const uint8_t eth_dst[ETH_ADDR_LEN],
 601                   const uint8_t eth_src[ETH_ADDR_LEN], uint16_t eth_type,
 602                   size_t size);
 603 void *snap_compose(struct ofpbuf *, const uint8_t eth_dst[ETH_ADDR_LEN],
 604                    const uint8_t eth_src[ETH_ADDR_LEN],
 605                    unsigned int oui, uint16_t snap_type, size_t size);
 606 void packet_set_ipv4(struct ofpbuf *, ovs_be32 src, ovs_be32 dst, uint8_t tos,
 607                      uint8_t ttl);
 608 void packet_set_ipv6(struct ofpbuf *, uint8_t proto, const ovs_be32 src[4],
 609                      const ovs_be32 dst[4], uint8_t tc,
 610                      ovs_be32 fl, uint8_t hlmit);
 611 void packet_set_tcp_port(struct ofpbuf *, ovs_be16 src, ovs_be16 dst);
 612 void packet_set_udp_port(struct ofpbuf *, ovs_be16 src, ovs_be16 dst);
 613 void packet_set_sctp_port(struct ofpbuf *, ovs_be16 src, ovs_be16 dst);
 614
 615 uint8_t packet_get_tcp_flags(const struct ofpbuf *, const struct flow *);
 616 void packet_format_tcp_flags(struct ds *, uint8_t);
 617
 618 #endif /* packets.h */