lib/packets.h

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