text: /*
   * Copyright (c) 2010, Swedish Institute of Computer Science.
   * All rights reserved.
   *
   * 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.
   *
   * This file is part of the Contiki operating system.
   *
   * \file
   *	Public API declarations for ContikiRPL.
   * \author
   *	Joakim Eriksson <joakime@sics.se> & Nicolas Tsiftes <nvt@sics.se>
   *
   */
  
  #ifndef RPL_H
  #define RPL_H
  
  #include "net/routing/rpl-classic/rpl-conf.h"
  
  #include "lib/list.h"
  #include "net/ipv6/uip.h"
  #include "net/ipv6/uip-ds6.h"
  #include "sys/ctimer.h"
  
  /*---------------------------------------------------------------------------*/
  typedef uint16_t rpl_rank_t;
  typedef uint16_t rpl_ocp_t;
  /*---------------------------------------------------------------------------*/
  /* IANA Routing Metric/Constraint Type as defined in RFC6551 */
  #define RPL_DAG_MC_NONE			            0 /* Local identifier for empty MC */
  #define RPL_DAG_MC_NSA                  1 /* Node State and Attributes */
  #define RPL_DAG_MC_ENERGY               2 /* Node Energy */
  #define RPL_DAG_MC_HOPCOUNT             3 /* Hop Count */
  #define RPL_DAG_MC_THROUGHPUT           4 /* Throughput */
  #define RPL_DAG_MC_LATENCY              5 /* Latency */
  #define RPL_DAG_MC_LQL                  6 /* Link Quality Level */
  #define RPL_DAG_MC_ETX                  7 /* Expected Transmission Count */
  #define RPL_DAG_MC_LC                   8 /* Link Color */
  
  /* IANA Routing Metric/Constraint Common Header Flag field as defined in RFC6551 (bit indexes) */
  #define RPL_DAG_MC_FLAG_P               5
  #define RPL_DAG_MC_FLAG_C               6
  #define RPL_DAG_MC_FLAG_O               7
  #define RPL_DAG_MC_FLAG_R               8
  
  /* IANA Routing Metric/Constraint Common Header A Field as defined in RFC6551 */
  #define RPL_DAG_MC_AGGR_ADDITIVE        0
  #define RPL_DAG_MC_AGGR_MAXIMUM         1
  #define RPL_DAG_MC_AGGR_MINIMUM         2
  #define RPL_DAG_MC_AGGR_MULTIPLICATIVE  3
  
  /* The bit index within the flags field of the rpl_metric_object_energy structure. */
  #define RPL_DAG_MC_ENERGY_INCLUDED	    3
  #define RPL_DAG_MC_ENERGY_TYPE		      1
  #define RPL_DAG_MC_ENERGY_ESTIMATION	  0
  
  /* IANA Node Type Field as defined in RFC6551 */
  #define RPL_DAG_MC_ENERGY_TYPE_MAINS		   0
  #define RPL_DAG_MC_ENERGY_TYPE_BATTERY		 1
  #define RPL_DAG_MC_ENERGY_TYPE_SCAVENGING	 2
  
  /* IANA Objective Code Point as defined in RFC6550 */
  #define RPL_OCP_OF0     0
  #define RPL_OCP_MRHOF   1
  
  struct rpl_metric_object_energy {
    uint8_t flags;
    uint8_t energy_est;
  };
  
  /* Logical representation of a DAG Metric Container. */
  struct rpl_metric_container {
    uint8_t type;
    uint8_t flags;
    uint8_t aggr;
    uint8_t prec;
    uint8_t length;
    union metric_object {
      struct rpl_metric_object_energy energy;
      uint16_t etx;
    } obj;
  };
  typedef struct rpl_metric_container rpl_metric_container_t;
  /*---------------------------------------------------------------------------*/
  struct rpl_instance;
  struct rpl_dag;
  /*---------------------------------------------------------------------------*/
  #define RPL_PARENT_FLAG_UPDATED           0x1
  #define RPL_PARENT_FLAG_LINK_METRIC_VALID 0x2
  
  struct rpl_parent {
    struct rpl_dag *dag;
  #if RPL_WITH_MC
    rpl_metric_container_t mc;
  #endif /* RPL_WITH_MC */
    rpl_rank_t rank;
    uint8_t dtsn;
    uint8_t flags;
  };
  typedef struct rpl_parent rpl_parent_t;
  /*---------------------------------------------------------------------------*/
  /* RPL DIO prefix suboption */
  struct rpl_prefix {
    uip_ipaddr_t prefix;
    uint32_t lifetime;
    uint8_t length;
    uint8_t flags;
  };
  typedef struct rpl_prefix rpl_prefix_t;
  /*---------------------------------------------------------------------------*/
  /* Directed Acyclic Graph */
  struct rpl_dag {
    uip_ipaddr_t dag_id;
    rpl_rank_t min_rank; /* should be reset per DAG iteration! */
    uint8_t version;
    uint8_t grounded;
    uint8_t preference;
    uint8_t used;
    /* live data for the DAG */
    uint8_t joined;
    rpl_parent_t *preferred_parent;
    rpl_rank_t rank;
    struct rpl_instance *instance;
    rpl_prefix_t prefix_info;
    uint32_t lifetime;
  };
  typedef struct rpl_dag rpl_dag_t;
  typedef struct rpl_instance rpl_instance_t;
  /*---------------------------------------------------------------------------*/
  /*
   * API for RPL objective functions (OF)
   *
   * reset(dag)
   *
   *  Resets the objective function state for a specific DAG. This function is
   *  called when doing a global repair on the DAG.
   *
   * parent_link_metric(parent)
   *
   *  Returns the link metric of a parent
   *
   * parent_has_usable_link(parent)
   *
   *  Returns 1 iff we have a usable link to this parent
   *
   * parent_path_cost(parent)
   *
   *  Returns the path cost of a parent
   *
   * rank_via_parent(parent)
   *
   *  Returns our rank if we select a given parent as preferred parent
   *
   * parent_is_acceptable
   *
   *  Returns 1 if a parent is usable as preferred parent, 0 otherwise
   *
   * best_parent(parent1, parent2)
   *
   *  Compares two parents and returns the best one, according to the OF.
   *
   * best_dag(dag1, dag2)
   *
   *  Compares two DAGs and returns the best one, according to the OF.
   *
   * update_metric_container(dag)
   *
   *  Updates the metric container for outgoing DIOs in a certain DAG.
   *  If the objective function of the DAG does not use metric containers,
   *  the function should set the object type to RPL_DAG_MC_NONE.
   *
   * dao_ack_callback(parent, status)
   *
   * A callback on the result of the DAO ACK. Similar to the neighbor link
   * callback. A failed DAO_ACK (NACK) can be used for switching to another
   * parent via changed link metric or other mechanisms.
   */
  struct rpl_of {
    void (*reset)(struct rpl_dag *);
  #if RPL_WITH_DAO_ACK
    void (*dao_ack_callback)(rpl_parent_t *, int status);
  #endif
    uint16_t (*parent_link_metric)(rpl_parent_t *);
    int (*parent_has_usable_link)(rpl_parent_t *);
    uint16_t (*parent_path_cost)(rpl_parent_t *);
    rpl_rank_t (*rank_via_parent)(rpl_parent_t *);
    rpl_parent_t *(*best_parent)(rpl_parent_t *, rpl_parent_t *);
    rpl_dag_t *(*best_dag)(rpl_dag_t *, rpl_dag_t *);
    void (*update_metric_container)( rpl_instance_t *);
    rpl_ocp_t ocp;
  };
  typedef struct rpl_of rpl_of_t;
  
  /*---------------------------------------------------------------------------*/
  /* Instance */
  struct rpl_instance {
    /* DAG configuration */
    rpl_metric_container_t mc;
    rpl_of_t *of;
    rpl_dag_t *current_dag;
    rpl_dag_t dag_table[RPL_MAX_DAG_PER_INSTANCE];
    /* The current default router - used for routing "upwards" */
    uip_ds6_defrt_t *def_route;
    uint8_t instance_id;
    uint8_t used;
    uint8_t dtsn_out;
    uint8_t mop;
    uint8_t dio_intdoubl;
    uint8_t dio_intmin;
    uint8_t dio_redundancy;
    uint8_t default_lifetime;
    uint8_t dio_intcurrent;
    uint8_t dio_send; /* for keeping track of which mode the timer is in */
    uint8_t dio_counter;
    /* my last registered DAO that I might be waiting for ACK on */
    uint8_t my_dao_seqno;
    uint8_t my_dao_transmissions;
    /* this is intended to keep track if this instance have a route downward */
    uint8_t has_downward_route;
    rpl_rank_t max_rankinc;
    rpl_rank_t min_hoprankinc;
    uint16_t lifetime_unit; /* lifetime in seconds = l_u * d_l */
  #if RPL_CONF_STATS
    uint16_t dio_totint;
    uint16_t dio_totsend;
    uint16_t dio_totrecv;
  #endif /* RPL_CONF_STATS */
    clock_time_t dio_next_delay; /* delay for completion of dio interval */
  #if RPL_WITH_PROBING
    struct ctimer probing_timer;
    rpl_parent_t *urgent_probing_target;
    int last_dag;
  #endif /* RPL_WITH_PROBING */
    struct ctimer dio_timer;
    struct ctimer dao_timer;
    struct ctimer dao_lifetime_timer;
    struct ctimer unicast_dio_timer;
    rpl_parent_t *unicast_dio_target;
  #if RPL_WITH_DAO_ACK
    struct ctimer dao_retransmit_timer;
  #endif /* RPL_WITH_DAO_ACK */
  };
  
  /*---------------------------------------------------------------------------*/
  /* Public RPL functions. */
  void uip_rpl_input(void);
  rpl_dag_t *rpl_set_root(uint8_t instance_id, uip_ipaddr_t *dag_id);
  int rpl_set_prefix(rpl_dag_t *dag, uip_ipaddr_t *prefix, unsigned len);
  int rpl_repair_root(uint8_t instance_id);
  int rpl_set_default_route(rpl_instance_t *instance, uip_ipaddr_t *from);
  rpl_dag_t *rpl_get_dag(const uip_ipaddr_t *addr);
  rpl_dag_t *rpl_get_any_dag(void);
  rpl_instance_t *rpl_get_instance(uint8_t instance_id);
  int rpl_ext_header_update(void);
  int rpl_ext_header_hbh_update(uint8_t *, int);
  void rpl_insert_header(void);
  bool rpl_ext_header_remove(void);
  const struct link_stats *rpl_get_parent_link_stats(rpl_parent_t *p);
  int rpl_parent_is_fresh(rpl_parent_t *p);
  int rpl_parent_is_reachable(rpl_parent_t *p);
  uint16_t rpl_get_parent_link_metric(rpl_parent_t *p);
  rpl_rank_t rpl_rank_via_parent(rpl_parent_t *p);
  const linkaddr_t *rpl_get_parent_lladdr(rpl_parent_t *p);
  uip_ipaddr_t *rpl_parent_get_ipaddr(rpl_parent_t *nbr);
  rpl_parent_t *rpl_get_parent(const uip_lladdr_t *addr);
  rpl_rank_t rpl_get_parent_rank(uip_lladdr_t *addr);
  void rpl_dag_init(void);
  uip_ds6_nbr_t *rpl_get_nbr(rpl_parent_t *parent);
  void rpl_print_neighbor_list(void);
  int rpl_ext_header_srh_update(void);
  int rpl_ext_header_srh_get_next_hop(uip_ipaddr_t *ipaddr);
  void rpl_link_callback(const linkaddr_t *addr, int status, int numtx);
  /* Per-parent RPL information */
  NBR_TABLE_DECLARE(rpl_parent_t, rpl_parents);
  
  /**
   * RPL modes
   *
   * The RPL module can be in either of three modes: mesh mode
   * (RPL_MODE_MESH), feater mode (RPL_MODE_FEATHER), and leaf mode
   * (RPL_MODE_LEAF). In mesh mode, nodes forward data for other nodes,
   * and are reachable by others. In feather mode, nodes can forward
   * data for other nodes, but are not reachable themselves. In leaf
   * mode, nodes do not forward data for others, but are reachable by
   * others. */
  enum rpl_mode {
    RPL_MODE_MESH = 0,
    RPL_MODE_FEATHER = 1,
    RPL_MODE_LEAF = 2,
  };
  
  /**
   * Set the RPL mode
   *
   * \param mode The new RPL mode
   * \retval The previous RPL mode
   */
  enum rpl_mode rpl_set_mode(enum rpl_mode mode);
  
  /**
   * Get the RPL mode
   *
   * \retval The RPL mode
   */
  enum rpl_mode rpl_get_mode(void);
  
  /**
   * Tells whether the node has joined a network or not
   *
   * \retval 1 if we have joined a network, 0 if not.
   */
  int rpl_has_joined(void);
  
  /**
   * Get the RPL's best guess on if we have downward route or not.
   *
   * \retval 1 if we have a downward route from RPL Root, 0 if not.
   */
  int rpl_has_downward_route(void);
  
  /**
   * Tells whether the protocol is in leaf mode
   *
   * \retval 1 if the protocol is in leaf mode, 0 if not.
   */
  uint8_t rpl_is_in_leaf_mode(void);
  
  /*---------------------------------------------------------------------------*/
  #endif /* RPL_H */
  