text: /**
   * \addtogroup uip
   * @{
   */
  
  /**
   * \file
   *    Header file for IPv6-related data structures
   * \author Mathilde Durvy <mdurvy@cisco.com>
   * \author Julien Abeille <jabeille@cisco.com>
   *
   */
  /*
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the Institute nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   *
   */
  
  #ifndef UIP_DS6_H_
  #define UIP_DS6_H_
  
  #include "net/ipv6/uip.h"
  #include "net/ipv6/multicast/uip-mcast6.h"
  #include "sys/stimer.h"
  /* The size of uip_ds6_addr_t depends on UIP_ND6_DEF_MAXDADNS. Include uip-nd6.h to define it. */
  #include "net/ipv6/uip-nd6.h"
  #include "net/ipv6/uip-ds6-nbr.h"
  #include "net/ipv6/uip-ds6-route.h"
  
  /*--------------------------------------------------*/
  /** Configuration. For all tables (Neighbor cache, Prefix List, Routing Table,
   * Default Router List, Unicast address list, multicast address list, anycast address list),
   * we define:
   * - the number of elements requested by the user in contiki configuration (name suffixed by _NBU)
   * - the number of elements assigned by the system (name suffixed by _NBS)
   * - the total number of elements is the sum (name suffixed by _NB)
   * The routing table definitions can be found in uip-ds6-route.h
   * The Neighbor cache definitions can be found in nbr-table.h
  */
  
  /* Default router list */
  #define UIP_DS6_DEFRT_NBS 0
  #ifndef UIP_CONF_DS6_DEFRT_NBU
  #define UIP_DS6_DEFRT_NBU 2
  #else
  #define UIP_DS6_DEFRT_NBU UIP_CONF_DS6_DEFRT_NBU
  #endif
  #define UIP_DS6_DEFRT_NB UIP_DS6_DEFRT_NBS + UIP_DS6_DEFRT_NBU
  
  /* Default prefix */
  #ifdef UIP_CONF_DS6_DEFAULT_PREFIX
  #define UIP_DS6_DEFAULT_PREFIX UIP_CONF_DS6_DEFAULT_PREFIX
  #else
  /* From RFC4193, section 3.1:
   *  | 7 bits |1|  40 bits   |  16 bits  |          64 bits           |
   *  +--------+-+------------+-----------+----------------------------+
   *  | Prefix |L| Global ID  | Subnet ID |        Interface ID        |
   *  +--------+-+------------+-----------+----------------------------+
   *     Prefix            FC00::/7 prefix to identify Local IPv6 unicast
   *                       addresses.
   *     L                 Set to 1 if the prefix is locally assigned.
   *                       Set to 0 may be defined in the future.  See
   *                       Section 3.2 for additional information.
   *     Global ID         40-bit global identifier used to create a
   *                       globally unique prefix.  See Section 3.2 for
   *                       additional information.
   *
   * We set prefix to 0xfc00 and set the local bit, resulting in 0xfd00.
   * For high probability of network uniqueness, Global ID must be generated
   * pseudo-randomly. As this is a hard-coded default prefix, we simply use
   * a Global ID of 0. For real deployments, make sure to install a pseudo-random
   * Global ID, e.g. in a RPL network, by configuring it at the root.
   */
  #define UIP_DS6_DEFAULT_PREFIX 0xfd00
  #endif /* UIP_CONF_DS6_DEFAULT_PREFIX */
  
  #define UIP_DS6_DEFAULT_PREFIX_0 ((UIP_DS6_DEFAULT_PREFIX >> 8) & 0xff)
  #define UIP_DS6_DEFAULT_PREFIX_1 (UIP_DS6_DEFAULT_PREFIX & 0xff)
  
  /* Prefix list */
  #define UIP_DS6_PREFIX_NBS  1
  #ifndef UIP_CONF_DS6_PREFIX_NBU
  #define UIP_DS6_PREFIX_NBU  2
  #else
  #define UIP_DS6_PREFIX_NBU UIP_CONF_DS6_PREFIX_NBU
  #endif
  #define UIP_DS6_PREFIX_NB UIP_DS6_PREFIX_NBS + UIP_DS6_PREFIX_NBU
  
  /* Unicast address list*/
  #define UIP_DS6_ADDR_NBS 1
  #ifndef UIP_CONF_DS6_ADDR_NBU
  #define UIP_DS6_ADDR_NBU 2
  #else
  #define UIP_DS6_ADDR_NBU UIP_CONF_DS6_ADDR_NBU
  #endif
  #define UIP_DS6_ADDR_NB UIP_DS6_ADDR_NBS + UIP_DS6_ADDR_NBU
  
  /* Multicast address list */
  #if UIP_CONF_ROUTER
  #define UIP_DS6_MADDR_NBS 2 + UIP_DS6_ADDR_NB   /* all routers + all nodes + one solicited per unicast */
  #else
  #define UIP_DS6_MADDR_NBS 1 + UIP_DS6_ADDR_NB   /* all nodes + one solicited per unicast */
  #endif
  #ifndef UIP_CONF_DS6_MADDR_NBU
  #define UIP_DS6_MADDR_NBU 0
  #else
  #define UIP_DS6_MADDR_NBU UIP_CONF_DS6_MADDR_NBU
  #endif
  #define UIP_DS6_MADDR_NB UIP_DS6_MADDR_NBS + UIP_DS6_MADDR_NBU
  
  /* Anycast address list */
  #if UIP_CONF_ROUTER
  #define UIP_DS6_AADDR_NBS UIP_DS6_PREFIX_NB - 1 /* One per non link local prefix (subnet prefix anycast address) */
  #else
  #define UIP_DS6_AADDR_NBS 0
  #endif
  #ifndef UIP_CONF_DS6_AADDR_NBU
  #define UIP_DS6_AADDR_NBU 0
  #else
  #define UIP_DS6_AADDR_NBU UIP_CONF_DS6_AADDR_NBU
  #endif
  #define UIP_DS6_AADDR_NB UIP_DS6_AADDR_NBS + UIP_DS6_AADDR_NBU
  
  /*--------------------------------------------------*/
  /* Should we use LinkLayer acks in NUD ?*/
  #ifndef UIP_CONF_DS6_LL_NUD
  #define UIP_DS6_LL_NUD 0
  #else
  #define UIP_DS6_LL_NUD UIP_CONF_DS6_LL_NUD
  #endif
  
  /** \brief Possible states for the an address  (RFC 4862) */
  #define ADDR_TENTATIVE 0
  #define ADDR_PREFERRED 1
  #define ADDR_DEPRECATED 2
  
  /** \brief How the address was acquired: Autoconf, DHCP or manually */
  #define  ADDR_ANYTYPE 0
  #define  ADDR_AUTOCONF 1
  #define  ADDR_DHCP 2
  #define  ADDR_MANUAL 3
  
  /** \brief General DS6 definitions */
  /** Period for uip-ds6 periodic task*/
  #ifndef UIP_DS6_CONF_PERIOD
  #define UIP_DS6_PERIOD   (60 * CLOCK_SECOND)
  #else
  #define UIP_DS6_PERIOD UIP_DS6_CONF_PERIOD
  #endif
  
  #define FOUND 0
  #define FREESPACE 1
  #define NOSPACE 2
  /*--------------------------------------------------*/
  
  #if UIP_CONF_IPV6_QUEUE_PKT
  #include "net/ipv6/uip-packetqueue.h"
  #endif                          /*UIP_CONF_QUEUE_PKT */
  
  /** \brief A prefix list entry */
  #if UIP_CONF_ROUTER
  typedef struct uip_ds6_prefix {
    uint8_t isused;
    uip_ipaddr_t ipaddr;
    uint8_t length;
    uint8_t advertise;
    uint32_t vlifetime;
    uint32_t plifetime;
    uint8_t l_a_reserved; /**< on-link and autonomous flags + 6 reserved bits */
  } uip_ds6_prefix_t;
  #else /* UIP_CONF_ROUTER */
  typedef struct uip_ds6_prefix {
    uint8_t isused;
    uip_ipaddr_t ipaddr;
    uint8_t length;
    struct stimer vlifetime;
    uint8_t isinfinite;
  } uip_ds6_prefix_t;
  #endif /*UIP_CONF_ROUTER */
  
  /** * \brief Unicast address structure */
  typedef struct uip_ds6_addr {
    uint8_t isused;
    uip_ipaddr_t ipaddr;
    uint8_t state;
    uint8_t type;
    uint8_t isinfinite;
    struct stimer vlifetime;
  #if UIP_ND6_DEF_MAXDADNS > 0
    struct timer dadtimer;
    uint8_t dadnscount;
  #endif /* UIP_ND6_DEF_MAXDADNS > 0 */
  } uip_ds6_addr_t;
  
  /** \brief Anycast address  */
  typedef struct uip_ds6_aaddr {
    uint8_t isused;
    uip_ipaddr_t ipaddr;
  } uip_ds6_aaddr_t;
  
  /** \brief A multicast address */
  typedef struct uip_ds6_maddr {
    uint8_t isused;
    uip_ipaddr_t ipaddr;
  } uip_ds6_maddr_t;
  
  /** \brief  Interface structure (contains all the interface variables) */
  typedef struct uip_ds6_netif {
    uint32_t link_mtu;
    uint8_t cur_hop_limit;
    uint32_t base_reachable_time; /* in msec */
    uint32_t reachable_time;      /* in msec */
    uint32_t retrans_timer;       /* in msec */
    uint8_t maxdadns;
  #if UIP_DS6_ADDR_NB
    uip_ds6_addr_t addr_list[UIP_DS6_ADDR_NB];
  #endif /* UIP_DS6_ADDR_NB */
  #if UIP_DS6_AADDR_NB
    uip_ds6_aaddr_t aaddr_list[UIP_DS6_AADDR_NB];
  #endif /* UIP_DS6_AADDR_NB */
  #if UIP_DS6_MADDR_NB
    uip_ds6_maddr_t maddr_list[UIP_DS6_MADDR_NB];
  #endif /* UIP_DS6_MADDR_NB */
  } uip_ds6_netif_t;
  
  /** \brief Generic type for a DS6, to use a common loop though all DS */
  typedef struct uip_ds6_element {
    uint8_t isused;
    uip_ipaddr_t ipaddr;
  } uip_ds6_element_t;
  
  
  /*---------------------------------------------------------------------------*/
  extern uip_ds6_netif_t uip_ds6_if;
  extern struct etimer uip_ds6_timer_periodic;
  
  #if UIP_CONF_ROUTER
  extern uip_ds6_prefix_t uip_ds6_prefix_list[UIP_DS6_PREFIX_NB];
  #else /* UIP_CONF_ROUTER */
  extern struct etimer uip_ds6_timer_rs;
  #endif /* UIP_CONF_ROUTER */
  
  
  /*---------------------------------------------------------------------------*/
  /** \brief Initialize data structures */
  void uip_ds6_init(void);
  
  /** \brief Periodic processing of data structures */
  void uip_ds6_periodic(void);
  
  /** \brief Generic loop routine on an abstract data structure, which generalizes
   * all data structures used in DS6 */
  uint8_t uip_ds6_list_loop(uip_ds6_element_t *list, uint8_t size,
                            uint16_t elementsize, uip_ipaddr_t *ipaddr,
                            uint8_t ipaddrlen,
                            uip_ds6_element_t **out_element);
  
  /** @} */
  
  
  /** \name Prefix list basic routines */
  /** @{ */
  #if UIP_CONF_ROUTER
  uip_ds6_prefix_t *uip_ds6_prefix_add(uip_ipaddr_t *ipaddr, uint8_t length,
                                       uint8_t advertise, uint8_t flags,
                                       unsigned long vtime,
                                       unsigned long ptime);
  #else /* UIP_CONF_ROUTER */
  uip_ds6_prefix_t *uip_ds6_prefix_add(uip_ipaddr_t *ipaddr, uint8_t length,
                                       unsigned long interval);
  #endif /* UIP_CONF_ROUTER */
  void uip_ds6_prefix_rm(uip_ds6_prefix_t *prefix);
  uip_ds6_prefix_t *uip_ds6_prefix_lookup(uip_ipaddr_t *ipaddr,
                                          uint8_t ipaddrlen);
  uint8_t uip_ds6_is_addr_onlink(uip_ipaddr_t *ipaddr);
  
  /**
   * \brief Retrieve the Default IPv6 prefix
   * \retval A pointer to the default prefix
   */
  const uip_ip6addr_t *uip_ds6_default_prefix(void);
  
  /**
   * \brief Set the Default IPv6 prefix
   * \param prefix A pointer to the new default prefix
   *
   * uip_ds6_init() will set the default prefix to UIP_DS6_DEFAULT_PREFIX
   * unless this function here has been called beforehand to set a new default
   * prefix.
   */
  void uip_ds6_set_default_prefix(const uip_ip6addr_t *prefix);
  
  /** @} */
  
  /** \name Unicast address list basic routines */
  /** @{ */
  /** \brief Add a unicast address to the interface */
  uip_ds6_addr_t *uip_ds6_addr_add(uip_ipaddr_t *ipaddr,
                                   unsigned long vlifetime, uint8_t type);
  void uip_ds6_addr_rm(uip_ds6_addr_t *addr);
  uip_ds6_addr_t *uip_ds6_addr_lookup(uip_ipaddr_t *ipaddr);
  uip_ds6_addr_t *uip_ds6_get_link_local(int8_t state);
  uip_ds6_addr_t *uip_ds6_get_global(int8_t state);
  
  /** @} */
  
  /** \name Multicast address list basic routines */
  /** @{ */
  uip_ds6_maddr_t *uip_ds6_maddr_add(const uip_ipaddr_t *ipaddr);
  void uip_ds6_maddr_rm(uip_ds6_maddr_t *maddr);
  uip_ds6_maddr_t *uip_ds6_maddr_lookup(const uip_ipaddr_t *ipaddr);
  
  /** @} */
  
  /** \name Anycast address list basic routines */
  /** @{ */
  uip_ds6_aaddr_t *uip_ds6_aaddr_add(uip_ipaddr_t *ipaddr);
  void uip_ds6_aaddr_rm(uip_ds6_aaddr_t *aaddr);
  uip_ds6_aaddr_t *uip_ds6_aaddr_lookup(uip_ipaddr_t *ipaddr);
  
  /** @} */
  
  
  /** \brief set the last 64 bits of an IP address based on the MAC address */
  void uip_ds6_set_addr_iid(uip_ipaddr_t *ipaddr, uip_lladdr_t *lladdr);
  
  /** \brief Build a link-layer address from an IPv6 address based on its UUID64 */
  void uip_ds6_set_lladdr_from_iid(uip_lladdr_t *lladdr, const uip_ipaddr_t *ipaddr);
  
  /** \brief Get the number of matching bits of two addresses */
  uint8_t get_match_length(uip_ipaddr_t *src, uip_ipaddr_t *dst);
  
  #if UIP_ND6_DEF_MAXDADNS >0
  /** \brief Perform Duplicate Address Selection on one address */
  void uip_ds6_dad(uip_ds6_addr_t *ifaddr);
  
  /** \brief Callback when DAD failed */
  int uip_ds6_dad_failed(uip_ds6_addr_t *ifaddr);
  #endif /* UIP_ND6_DEF_MAXDADNS */
  
  /** \brief Source address selection, see RFC 3484 */
  void uip_ds6_select_src(uip_ipaddr_t *src, uip_ipaddr_t *dst);
  
  #if UIP_CONF_ROUTER
  #if UIP_ND6_SEND_RA
  /** \brief Send a RA as an asnwer to a RS */
  void uip_ds6_send_ra_sollicited(void);
  
  /** \brief Send a periodic RA */
  void uip_ds6_send_ra_periodic(void);
  #endif /* UIP_ND6_SEND_RA */
  #else /* UIP_CONF_ROUTER */
  /** \brief Send periodic RS to find router */
  void uip_ds6_send_rs(void);
  #endif /* UIP_CONF_ROUTER */
  
  /** \brief Compute the reachable time based on base reachable time, see RFC 4861*/
  uint32_t uip_ds6_compute_reachable_time(void); /** \brief compute random reachable timer */
  
  /** \name Macros to check if an IP address (unicast, multicast or anycast) is mine */
  /** @{ */
  #define uip_ds6_is_my_addr(addr)  (uip_ds6_addr_lookup(addr) != NULL)
  #define uip_ds6_is_my_maddr(addr) (uip_ds6_maddr_lookup(addr) != NULL)
  #define uip_ds6_is_my_aaddr(addr) (uip_ds6_aaddr_lookup(addr) != NULL)
  /** @} */
  /** @} */
  
  #endif /* UIP_DS6_H_ */
  