Merge pull request #2910 from authmillenon/ng_ndp/feat/addr-res

ng_ndp: initial import of address resolution

Makefile.dep

@@ -72,6 +72,13 @@ ifneq (,$(filter ng_sixlowpan_ctx,$(USEMODULE)))
   USEMODULE += vtimer
 endif
 
+ifneq (,$(filter ng_ndp,$(USEMODULE)))
+  USEMODULE += ng_icmpv6
+  USEMODULE += random
+  USEMODULE += timex
+  USEMODULE += vtimer
+endif
+
 ifneq (,$(filter ng_icmpv6_echo,$(USEMODULE)))
   USEMODULE += ng_icmpv6
   USEMODULE += ng_netbase
@@ -97,7 +104,11 @@ ifneq (,$(filter ng_ipv6,$(USEMODULE)))
   USEMODULE += ng_ipv6_hdr
   USEMODULE += ng_ipv6_nc
   USEMODULE += ng_ipv6_netif
+  USEMODULE += ng_ndp
   USEMODULE += ng_netbase
+  USEMODULE += random
+  USEMODULE += timex
+  USEMODULE += vtimer
 endif
 
 ifneq (,$(filter ng_ipv6_nc,$(USEMODULE)))

sys/Makefile

@@ -86,6 +86,9 @@ endif
 ifneq (,$(filter ng_inet_csum,$(USEMODULE)))
     DIRS += net/crosslayer/ng_inet_csum
 endif
+ifneq (,$(filter ng_ndp,$(USEMODULE)))
+    DIRS += net/network_layer/ng_ndp
+endif
 ifneq (,$(filter ng_netapi,$(USEMODULE)))
     DIRS += net/crosslayer/ng_netapi
 endif

sys/include/net/ng_ipv6.h

@@ -62,6 +62,16 @@ extern "C" {
 #define NG_IPV6_MSG_QUEUE_SIZE  (8U)
 #endif
 
+/**
+ * @brief   The PID to the IPv6 thread.
+ *
+ * @note    Use @ref ng_ipv6_init() to initialize. **Do not set by hand**.
+ *
+ * @details This variable is preferred for IPv6 internal communication *only*.
+ *          Please use @ref net_ng_netreg for external communication.
+ */
+extern kernel_pid_t ng_ipv6_pid;
+
 /**
  * @brief   Initialization of the IPv6 thread.
  *

sys/include/net/ng_ipv6/nc.h

@@ -137,7 +137,7 @@ typedef struct {
      */
     vtimer_t nbr_adv_timer;
 
-    uint8_t unanswered_probes;              /**< number of unanswered probes */
+    uint8_t probes_remaining;               /**< remaining number of unanswered probes */
     /**
      * @}
      */

sys/include/net/ng_ipv6/netif.h

@@ -195,6 +195,29 @@ typedef struct {
     uint16_t mtu;           /**< Maximum Transmission Unit (MTU) of the interface */
     uint8_t cur_hl;         /**< current hop limit for the interface */
     uint16_t flags;         /**< flags for 6LoWPAN and Neighbor Discovery */
+    /**
+     * @brief   Base value in microseconds for computing random
+     *          ng_ipv6_netif_t::reach_time.
+     *          The default value is @ref NG_NDP_REACH_TIME.
+     */
+    uint32_t reach_time_base;
+
+    /**
+     * @brief   The time a neighbor is considered reachable after receiving
+     *          a reachability confirmation.
+     *          Should be uniformly distributed between @ref NG_NDP_MIN_RAND
+     *          and NG_NDP_MAX_RAND multiplied with
+     *          ng_ipv6_netif_t::reach_time_base microseconds devided by 10.
+     *          Can't be greater than 1 hour.
+     */
+    timex_t reach_time;
+
+    /**
+     * @brief   Time between retransmissions of neighbor solicitations to a
+     *          neighbor.
+     *          The default value is @ref NG_NDP_RETRANS_TIMER.
+     */
+    timex_t retrans_timer;
 } ng_ipv6_netif_t;
 
 /**

sys/include/net/ng_ndp.h

+/*
+ * Copyright (C) 2015 Martine Lenders <mlenders@inf.fu-berlin.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser General
+ * Public License v2.1. See the file LICENSE in the top level directory for
+ * more details.
+ */
+
+/**
+ * @defgroup    net_ng_ndp  IPv6 Neighbor discovery
+ * @ingroup     net_ng_icmpv6
+ * @brief       IPv6 Neighbor Discovery Implementation
+ * @{
+ *
+ * @file
+ * @brief       Neighbor Discovery definitions
+ *
+ * @author      Martine Lenders <mlenders@inf.fu-berlin.de>
+ */
+
+#include <inttypes.h>
+
+#include "byteorder.h"
+#include "net/ng_pkt.h"
+#include "net/ng_icmpv6.h"
+#include "net/ng_ipv6/addr.h"
+#include "net/ng_ipv6/nc.h"
+#include "net/ng_ipv6/netif.h"
+
+#include "net/ng_ndp/types.h"
+
+#ifndef NG_NDP_H_
+#define NG_NDP_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define NG_NDP_MSG_RTR_TIMEOUT      (0x0211)    /**< Message type for router timeouts */
+#define NG_NDP_MSG_ADDR_TIMEOUT     (0x0212)    /**< Message type for address timeouts */
+#define NG_NDP_MSG_NBR_SOL_RETRANS  (0x0213)    /**< Message type for multicast
+                                                 *   neighbor solicitation retransmissions */
+#define NG_NDP_MSG_NC_STATE_TIMEOUT (0x0214)    /**< Message type for neighbor cache state timeouts */
+
+/**
+ * @{
+ * @name    Node constants
+ * @see     <a href="https://tools.ietf.org/html/rfc4861#section-10">
+ *              RFC 4861, section 10
+ *          </a>
+ */
+/**
+ * @brief   Maximum number of unanswered multicast neighbor solicitations
+ *          before address resolution is considered failed.
+ */
+#define NG_NDP_MAX_MC_NBR_SOL_NUMOF (3U)
+
+/**
+ * @brief   Maximum number of unanswered unicast neighbor solicitations before
+ *          an address is considered unreachable.
+ */
+#define NG_NDP_MAX_UC_NBR_SOL_NUMOF (3U)
+
+/**
+ * @brief   Upper bound of randomized delay in seconds for a solicited
+ *          neighbor advertisement transmission for an anycast target.
+ */
+#define NG_NDP_MAX_AC_TGT_DELAY     (1U)
+
+/**
+ * @brief   Maximum number of unsolicited neighbor advertisements before on
+ *          link-layer address change.
+ */
+#define NG_NDP_MAX_NBR_ADV_NUMOF    (3U)
+
+/**
+ * @brief   Base value in mircoseconds for computing randomised
+ *          reachable time.
+ */
+#define NG_NDP_REACH_TIME           (30U * SEC_IN_USEC)
+
+/**
+ * @brief   Time in mircoseconds between retransmissions of neighbor
+ *          solicitations to a neighbor.
+ */
+#define NG_NDP_RETRANS_TIMER        (1U * SEC_IN_USEC)
+
+/**
+ * @brief   Delay in seconds for neighbor cache entry between entering
+ *          DELAY state and entering PROBE state if no reachability
+ *          confirmation has been received.
+ */
+#define NG_NDP_FIRST_PROBE_DELAY    (5U)
+
+/**
+ * @brief   Lower bound for randomised reachable time calculation.
+ */
+#define NG_NDP_MIN_RAND             (5U)
+
+/**
+ * @brief   Upper bound for randomised reachable time calculation.
+ */
+#define NG_NDP_MAX_RAND             (15U)
+/**
+ * @}
+ */
+
+/**
+ * @brief   Handles received neighbor solicitations
+ *
+ * @param[in] iface         The receiving interface.
+ * @param[in] pkt           The received packet.
+ * @param[in] ipv6          The IPv6 header in @p pkt.
+ * @param[in] nbr_sol       The neighbor solicitation in @p pkt.
+ * @param[in] icmpv6_size   The overall size of the neighbor solicitation
+ */
+void ng_ndp_nbr_sol_handle(kernel_pid_t iface, ng_pktsnip_t *pkt,
+                           ng_ipv6_hdr_t *ipv6, ng_ndp_nbr_sol_t *nbr_sol,
+                           size_t icmpv6_size);
+
+/**
+ * @brief   Handles received neighbor solicitations
+ *
+ * @param[in] iface         The receiving interface.
+ * @param[in] pkt           The received packet.
+ * @param[in] ipv6          The IPv6 header in @p pkt.
+ * @param[in] nbr_adv       The neighbor advertisement in @p pkt.
+ * @param[in] icmpv6_size   The overall size of the neighbor solicitation
+ */
+void ng_ndp_nbr_adv_handle(kernel_pid_t iface, ng_pktsnip_t *pkt,
+                           ng_ipv6_hdr_t *ipv6, ng_ndp_nbr_adv_t *nbr_adv,
+                           size_t icmpv6_size);
+
+/**
+ * @brief   Retransmits a multicast neighbor solicitation for an incomplete or
+ *          probing neighbor cache entry @p nc_entry,
+ *          if nc_entry::probes_remaining > 0.
+ *
+ * @details If nc_entry::probes_remaining > 0 it will be decremented. If it
+ *          reaches 0 it the entry @p nc_entry will be removed from the
+ *          neighbor cache.
+ *
+ * @param[in]   nc_entry    A neighbor cache entry. Will be ignored if its state
+ *                          is not @ref NG_IPV6_NC_STATE_INCOMPLETE or
+ *                          @ref NG_IPV6_NC_STATE_PROBE.
+ */
+void ng_ndp_retrans_nbr_sol(ng_ipv6_nc_t *nc_entry);
+
+/**
+ * @brief   Event handler for a neighbor cache state timeout.
+ *
+ * @param[in]   nc_entry    A neighbor cache entry.
+ */
+void ng_ndp_state_timeout(ng_ipv6_nc_t *nc_entry);
+
+/**
+ * @brief   NDP interface initialization.
+ *
+ * @param[in] iface     An IPv6 interface descriptor. Must not be NULL.
+ */
+void ng_ndp_netif_add(ng_ipv6_netif_t *iface);
+
+/**
+ * @brief   NDP interface removal.
+ *
+ * @param[in] iface     An IPv6 interface descriptor. Must not be NULL.
+ */
+void ng_ndp_netif_remove(ng_ipv6_netif_t *iface);
+
+/**
+ * @brief   Get link-layer address and interface for next hop to destination
+ *          IPv6 address.
+ *
+ * @param[out] l2addr           The link-layer for the next hop to @p dst.
+ * @param[out] l2addr_len       Length of @p l2addr.
+ * @param[in] iface             The interface to search the next hop on.
+ *                              May be @ref KERNEL_PID_UNDEF if not specified.
+ * @param[in] dst               An IPv6 address to search the next hop for.
+ * @param[in] pkt               Packet to send to @p dst. Leave NULL if you
+ *                              just want to get the addresses.
+ *
+ * @return  The PID of the interface, on success.
+ * @return  -EHOSTUNREACH, if @p dst is not reachable.
+ * @return  -ENOBUFS, if @p l2addr_len was smaller than the resulting @p l2addr
+ *          would be long.
+ */
+kernel_pid_t ng_ndp_next_hop_l2addr(uint8_t *l2addr, uint8_t *l2addr_len,
+                                    kernel_pid_t iface, ng_ipv6_addr_t *dst,
+                                    ng_pktsnip_t *pkt);
+
+/**
+ * @brief   Builds a neighbor solicitation message for sending.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.3">
+ *          RFC 4861, section 4.3
+ *      </a>
+ *
+ * @param[in] tgt       The target address.
+ * @param[in] options   Options to append to the router solicitation.
+ *
+ * @return  The resulting ICMPv6 packet on success.
+ * @return  NULL, on failure.
+ */
+ng_pktsnip_t *ng_ndp_nbr_sol_build(ng_ipv6_addr_t *tgt, ng_pktsnip_t *options);
+
+/**
+ * @brief   Builds a neighbor advertisement message for sending.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.4">
+ *          RFC 4861, section 4.4
+ *      </a>
+ *
+ * @param[in] flags     Flags as defined above.
+ *                      @ref NG_NDP_NBR_ADV_FLAGS_R == 1 indicates, that the
+ *                      sender is a router,
+ *                      @ref NG_NDP_NBR_ADV_FLAGS_S == 1 indicates that the
+ *                      advertisement was sent in response to a neighbor
+ *                      solicitation,
+ *                      @ref NG_NDP_NBR_ADV_FLAGS_O == 1 indicates that the
+ *                      advertisement should override an existing cache entry
+ *                      and update the cached link-layer address.
+ * @param[in] tgt       For solicited advertisements, the Target Address field
+ *                      in the neighbor solicitaton.
+ *                      For and unsolicited advertisement, the address whose
+ *                      link-layer addres has changed.
+ *                      MUST NOT be multicast.
+ * @param[in] options   Options to append to the neighbor advertisement.
+ *
+ * @return  The resulting ICMPv6 packet on success.
+ * @return  NULL, on failure.
+ */
+ng_pktsnip_t *ng_ndp_nbr_adv_build(uint8_t flags, ng_ipv6_addr_t *tgt,
+                                   ng_pktsnip_t *options);
+
+/**
+ * @brief   Builds a generic NDP option.
+ *
+ * @param[in] type  Type of the option.
+ * @param[in] size  Size in byte of the option (will be rounded up to the next
+ *                  multiple of 8).
+ * @param[in] next  More options in the packet. NULL, if there are none.
+ *
+ * @return  The packet snip list of options, on success
+ * @return  NULL, if packet buffer is full
+ */
+ng_pktsnip_t *ng_ndp_opt_build(uint8_t type, size_t size, ng_pktsnip_t *next);
+
+/**
+ * @brief   Builds the source link-layer address option.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.6.1">
+ *          RFC 4861, section 4.6.1
+ *      </a>
+ *
+ * @note    Must only be used with neighbor solicitations, router solicitations,
+ *          and router advertisements. This is not checked however, since
+ *          hosts should silently ignore it in other NDP messages.
+ *
+ * @param[in] l2addr        A link-layer address of variable length.
+ * @param[in] l2addr_len    Length of @p l2addr.
+ * @param[in] next          More options in the packet. NULL, if there are none.
+ *
+ * @return  The packet snip list of options, on success
+ * @return  NULL, if packet buffer is full
+ */
+ng_pktsnip_t *ng_ndp_opt_sl2a_build(const uint8_t *l2addr, uint8_t l2addr_len,
+                                    ng_pktsnip_t *next);
+
+/**
+ * @brief   Builds the target link-layer address option.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.6.1">
+ *          RFC 4861, section 4.6.1
+ *      </a>
+ *
+ * @note    Must only be used with neighbor advertisemnents and redirect packets.
+ *          This is not checked however, since hosts should silently ignore it
+ *          in other NDP messages.
+ *
+ * @param[in] l2addr        A link-layer address of variable length.
+ * @param[in] l2addr_len    Length of @p l2addr.
+ * @param[in] next          More options in the packet. NULL, if there are none.
+ *
+ * @return  The pkt snip list of options, on success
+ * @return  NULL, if packet buffer is full
+ */
+ng_pktsnip_t *ng_ndp_opt_tl2a_build(const uint8_t *l2addr, uint8_t l2addr_len,
+                                    ng_pktsnip_t *next);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NG_NDP_H_ */
+/**
+ * @}
+ */

sys/include/net/ng_ndp/types.h

+/*
+ * Copyright (C) 2015 Martine Lenders <mlenders@inf.fu-berlin.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup    net_ng_ndp_types    Types for IPv6 neighbor discovery
+ * @ingroup     net_ng_ndp
+ * @brief       IPv6 neighbor discovery message types
+ * @{
+ *
+ * @file
+ * @brief       IPv6 neighbor discovery message type definitions
+ *
+ * @author  Martine Lenders <mlenders@inf.fu-berlin.de>
+ */
+#ifndef NG_NDP_TYPES_H_
+#define NG_NDP_TYPES_H_
+
+#include <stdint.h>
+
+#include "byteorder.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @{
+ * @name    Flags for router advertisement messages
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.2">
+ *          RFC 4861, section 4.2
+ *      </a>
+ */
+#define NG_NDP_RTR_ADV_FLAGS_MASK   (0xc0)
+#define NG_NDP_RTR_ADV_FLAGS_M      (0x80)  /**< managed address configuration */
+#define NG_NDP_RTR_ADV_FLAGS_O      (0x40)  /**< other configuration */
+/**
+ * @}
+ */
+
+/**
+ * @{
+ * @name    Flags for neighbor advertisement messages
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.4">
+ *          RFC 4861, section 4.2
+ *      </a>
+ */
+#define NG_NDP_NBR_ADV_FLAGS_MASK   (0xe0)
+#define NG_NDP_NBR_ADV_FLAGS_R      (0x80)  /**< router */
+#define NG_NDP_NBR_ADV_FLAGS_S      (0x40)  /**< solicited */
+#define NG_NDP_NBR_ADV_FLAGS_O      (0x20)  /**< override */
+/**
+ * @}
+ */
+
+/**
+ * @{
+ * @name    NDP option types
+ * @see <a href="http://www.iana.org/assignments/icmpv6-parameters/icmpv6-parameters.xhtml#icmpv6-parameters-5">
+ *          IANA, IPv6 Neighbor Discovery Option Formats
+ *      </a>
+ */
+#define NG_NDP_OPT_SL2A             (1)     /**< source link-layer address option */
+#define NG_NDP_OPT_TL2A             (2)     /**< target link-layer address option */
+#define NG_NDP_OPT_PI               (3)     /**< prefix information option */
+#define NG_NDP_OPT_RH               (4)     /**< redirected option */
+#define NG_NDP_OPT_MTU              (5)     /**< MTU option */
+/**
+ * @}
+ */
+
+/**
+ * @{
+ * @name    Flags for prefix information option
+ */
+#define NG_NDP_OPT_PI_FLAGS_MASK    (0xc0)
+#define NG_NDP_OPT_PI_FLAGS_L       (0x80)  /**< on-link */
+#define NG_NDP_OPT_PI_FLAGS_A       (0x40)  /**< autonomous address configuration */
+/**
+ * @}
+ */
+
+/**
+ * @{
+ * @name    Lengths for fixed length options
+ * @brief   Options don't use bytes as their length unit, but 8 bytes.
+ */
+#define NG_NDP_OPT_PI_LEN           (4U)
+#define NG_NDP_OPT_MTU_LEN          (1U)
+/**
+ * @}
+ */
+
+/**
+ * @brief   Router solicitation message format.
+ * @extends ng_icmpv6_hdr_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.1">
+ *          RFC 4861, section 4.1
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;           /**< message type */
+    uint8_t code;           /**< message code */
+    network_uint16_t csum;  /**< checksum */
+    network_uint32_t resv;  /**< reserved field */
+} ng_ndp_rtr_sol_t;
+
+/**
+ * @brief   Router advertisement message format.
+ * @extends ng_icmpv6_hdr_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.2">
+ *          RFC 4861, section 4.2
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;                       /**< message type */
+    uint8_t code;                       /**< message code */
+    network_uint16_t csum;              /**< checksum */
+    uint8_t cur_hl;                     /**< current hop limit */
+    uint8_t flags;                      /**< flags */
+    network_uint16_t ltime;             /**< router lifetime */
+    network_uint32_t reach_time;        /**< reachable time */
+    network_uint32_t retrans_timer;     /**< retransmission timer */
+} ng_ndp_rtr_adv_t;
+
+/**
+ * @brief   Neighbor solicitation message format.
+ * @extends ng_icmpv6_hdr_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.3">
+ *          RFC 4861, section 4.3
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;           /**< message type */
+    uint8_t code;           /**< message code */
+    network_uint16_t csum;  /**< checksum */
+    network_uint32_t resv;  /**< reserved field */
+    ng_ipv6_addr_t tgt;     /**< target address */
+} ng_ndp_nbr_sol_t;
+
+/**
+ * @brief   Neighbor advertisement message format.
+ * @extends ng_icmpv6_hdr_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.4">
+ *          RFC 4861, section 4.4
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;           /**< message type */
+    uint8_t code;           /**< message code */
+    network_uint16_t csum;  /**< checksum */
+    uint8_t flags;          /**< flags */
+    uint8_t resv[3];        /**< reserved fields */
+    ng_ipv6_addr_t tgt;     /**< target address */
+} ng_ndp_nbr_adv_t;
+
+/**
+ * @brief   Neighbor advertisement message format.
+ * @extends ng_icmpv6_hdr_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.5">
+ *          RFC 4861, section 4.5
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;           /**< message type */
+    uint8_t code;           /**< message code */
+    network_uint16_t csum;  /**< checksum */
+    network_uint32_t resv;  /**< reserved field */
+    ng_ipv6_addr_t tgt;     /**< target address */
+    ng_ipv6_addr_t dst;     /**< destination address */
+} ng_ndp_redirect_t;
+
+/**
+ * @brief   General NDP option format
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.6">
+ *          RFC 4861, section 4.6
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;   /**< option type */
+    uint8_t len;    /**< length in units of 8 octets */
+} ng_ndp_opt_t;
+
+/* XXX: slla and tlla are just ng_ndp_opt_t with variable link layer address
+ * appended */
+
+/**
+ * @brief   Prefix information option format
+ * @extends ng_ndp_opt_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.6.2">
+ *          RFC 4861, section 4.6.2
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;                   /**< option type */
+    uint8_t len;                    /**< length in units of 8 octets */
+    uint8_t prefix_len;             /**< prefix length */
+    uint8_t flags;                  /**< flags */
+    network_uint32_t valid_ltime;   /**< valid lifetime */
+    network_uint32_t pref_ltime;    /**< preferred lifetime */
+    network_uint32_t resv;          /**< reserved field */
+    ng_ipv6_addr_t prefix;          /**< prefix */
+} ng_ndp_opt_pi_t;
+
+/**
+ * @brief   Redirected header option format
+ * @extends ng_ndp_opt_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.6.3">
+ *          RFC 4861, section 4.6.3
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;           /**< option type */
+    uint8_t len;            /**< length in units of 8 octets */
+    uint8_t resv[6];        /**< reserved field */
+} ng_ndp_opt_rh_t;
+
+/**
+ * @brief   MTU option format
+ * @extends ng_ndp_opt_t
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc4861#section-4.6.4">
+ *          RFC 4861, section 4.6.4
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;           /**< option type */
+    uint8_t len;            /**< length in units of 8 octets */
+    network_uint16_t resv;  /**< reserved field */
+    network_uint32_t mtu;   /**< MTU */
+} ng_ndp_opt_mtu_t;
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NG_NDP_TYPES_H_ */
+/** @} */

sys/net/network_layer/ng_icmpv6/ng_icmpv6.c

@@ -24,6 +24,7 @@
 #include "net/ng_netbase.h"
 #include "net/ng_protnum.h"
 #include "net/ng_ipv6/hdr.h"
+#include "net/ng_ndp.h"
 #include "od.h"
 #include "utlist.h"
 
@@ -83,16 +84,32 @@ void ng_icmpv6_demux(kernel_pid_t iface, ng_pktsnip_t *pkt)
             break;
 #endif
 
-#ifdef MODULE_NG_NDP
         case NG_ICMPV6_RTR_SOL:
+            DEBUG("icmpv6: router solicitation received\n");
+            /* TODO */
+            break;
+
         case NG_ICMPV6_RTR_ADV:
+            DEBUG("icmpv6: router advertisement received\n");
+            /* TODO */
+            break;
+
         case NG_ICMPV6_NBR_SOL:
+            DEBUG("icmpv6: neighbor solicitation received\n");
+            ng_ndp_nbr_sol_handle(iface, pkt, ipv6->data, (ng_ndp_nbr_sol_t *)hdr,
+                                  icmpv6->size);
+            break;
+
         case NG_ICMPV6_NBR_ADV:
+            DEBUG("icmpv6: neighbor advertisement received\n");
+            ng_ndp_nbr_adv_handle(iface, pkt, ipv6->data, (ng_ndp_nbr_adv_t *)hdr,
+                                  icmpv6->size);
+            break;
+
         case NG_ICMPV6_REDIRECT:
-            DEBUG("icmpv6: neighbor discovery message received\n");
+            DEBUG("icmpv6: redirect message received\n");
             /* TODO */
             break;
-#endif
 
 #ifdef MODULE_NG_RPL
         case NG_ICMPV6_RPL_CTRL:

sys/net/network_layer/ng_ipv6/nc/ng_ipv6_nc.c

@@ -15,8 +15,14 @@
 #include <errno.h>
 #include <string.h>
 
+#include "net/ng_ipv6.h"
 #include "net/ng_ipv6/addr.h"
 #include "net/ng_ipv6/nc.h"
+#include "net/ng_ipv6/netif.h"
+#include "net/ng_ndp.h"
+#include "thread.h"
+#include "timex.h"
+#include "vtimer.h"
 
 #define ENABLE_DEBUG    (0)
 #include "debug.h"
@@ -110,6 +116,11 @@ ng_ipv6_nc_t *ng_ipv6_nc_add(kernel_pid_t iface, const ng_ipv6_addr_t *ipv6_addr
 
     DEBUG(" with flags = 0x%0x\n", flags);
 
+    if (ng_ipv6_nc_get_state(free_entry) == NG_IPV6_NC_STATE_INCOMPLETE) {
+        DEBUG("ipv6_nc: Set remaining probes to %" PRIu8 "\n");
+        free_entry->probes_remaining = NG_NDP_MAX_MC_NBR_SOL_NUMOF;
+    }
+
     return free_entry;
 }
 
@@ -192,8 +203,16 @@ ng_ipv6_nc_t *ng_ipv6_nc_still_reachable(const ng_ipv6_addr_t *ipv6_addr)
         return NULL;
     }
 
-    if (((entry->flags & NG_IPV6_NC_STATE_MASK) >> NG_IPV6_NC_STATE_POS) !=
-        NG_IPV6_NC_STATE_INCOMPLETE) {
+    if (ng_ipv6_nc_get_state(entry) != NG_IPV6_NC_STATE_INCOMPLETE) {
+#if defined(MODULE_NG_IPV6_NETIF) && defined(MODULE_VTIMER) && defined(MODULE_NG_IPV6)
+        ng_ipv6_netif_t *iface = ng_ipv6_netif_get(entry->iface);
+        timex_t t = iface->reach_time;
+
+        vtimer_remove(&entry->nbr_sol_timer);
+        vtimer_set_msg(&entry->nbr_sol_timer, t, ng_ipv6_pid,
+                       NG_NDP_MSG_NC_STATE_TIMEOUT, entry);
+#endif
+
         DEBUG("ipv6_nc: Marking entry %s as reachable\n",
               ng_ipv6_addr_to_str(addr_str, ipv6_addr, sizeof(addr_str)));
         entry->flags &= ~(NG_IPV6_NC_STATE_MASK >> NG_IPV6_NC_STATE_POS);

sys/net/network_layer/ng_ipv6/netif/ng_ipv6_netif.c

@@ -21,6 +21,7 @@
 #include "kernel_types.h"
 #include "mutex.h"
 #include "net/ng_ipv6/addr.h"
+#include "net/ng_ndp.h"
 #include "net/ng_netif.h"
 
 #include "net/ng_ipv6/netif.h"
@@ -119,6 +120,10 @@ void ng_ipv6_netif_add(kernel_pid_t pid)
 
             mutex_unlock(&ipv6_ifs[i].mutex);
 
+#ifdef MODULE_NG_NDP
+            ng_ndp_netif_add(&ipv6_ifs[i]);
+#endif
+
             DEBUG(" * pid = %" PRIkernel_pid "  ", ipv6_ifs[i].pid);
             DEBUG("cur_hl = %d  ", ipv6_ifs[i].cur_hl);
             DEBUG("mtu = %d  ", ipv6_ifs[i].mtu);
@@ -138,6 +143,10 @@ void ng_ipv6_netif_remove(kernel_pid_t pid)
         return;
     }
 
+#ifdef MODULE_NG_NDP
+    ng_ndp_netif_remove(entry);
+#endif
+
     mutex_lock(&entry->mutex);
 
     _reset_addr_from_entry(entry);

sys/net/network_layer/ng_ipv6/ng_ipv6.c

@@ -20,6 +20,7 @@
 #include "kernel_types.h"
 #include "net/ng_icmpv6.h"
 #include "net/ng_netbase.h"
+#include "net/ng_ndp.h"
 #include "net/ng_protnum.h"
 #include "thread.h"
 #include "utlist.h"
@@ -35,12 +36,13 @@
 #define _MAX_L2_ADDR_LEN    (8U)
 
 static char _stack[NG_IPV6_STACK_SIZE];
-static kernel_pid_t _pid = KERNEL_PID_UNDEF;
 
 #if ENABLE_DEBUG
 static char addr_str[NG_IPV6_ADDR_MAX_STR_LEN];
 #endif
 
+kernel_pid_t ng_ipv6_pid = KERNEL_PID_UNDEF;
+
 /* handles NG_NETAPI_MSG_TYPE_RCV commands */
 static void _receive(ng_pktsnip_t *pkt);
 /* dispatches received IPv6 packet for upper layer */
@@ -58,12 +60,12 @@ static void _decapsulate(ng_pktsnip_t *pkt);
 
 kernel_pid_t ng_ipv6_init(void)
 {
-    if (_pid == KERNEL_PID_UNDEF) {
-        _pid = thread_create(_stack, sizeof(_stack), NG_IPV6_PRIO,
+    if (ng_ipv6_pid == KERNEL_PID_UNDEF) {
+        ng_ipv6_pid = thread_create(_stack, sizeof(_stack), NG_IPV6_PRIO,
                              CREATE_STACKTEST, _event_loop, NULL, "ipv6");
     }
 
-    return _pid;
+    return ng_ipv6_pid;
 }
 
 void ng_ipv6_demux(kernel_pid_t iface, ng_pktsnip_t *pkt, uint8_t nh)
@@ -140,6 +142,27 @@ static void *_event_loop(void *args)
                 msg_reply(&msg, &reply);
                 break;
 
+            case NG_NDP_MSG_RTR_TIMEOUT:
+                DEBUG("ipv6: Router timeout received\n");
+                ((ng_ipv6_nc_t *)msg.content.ptr)->flags &= ~NG_IPV6_NC_IS_ROUTER;
+                break;
+
+            case NG_NDP_MSG_ADDR_TIMEOUT:
+                DEBUG("ipv6: Router advertisement timer event received\n");
+                ng_ipv6_netif_remove_addr(KERNEL_PID_UNDEF,
+                                          (ng_ipv6_addr_t *)msg.content.ptr);
+                break;
+
+            case NG_NDP_MSG_NBR_SOL_RETRANS:
+                DEBUG("ipv6: Neigbor solicitation retransmission timer event received\n");
+                ng_ndp_retrans_nbr_sol((ng_ipv6_nc_t *)msg.content.ptr);
+                break;
+
+            case NG_NDP_MSG_NC_STATE_TIMEOUT:
+                DEBUG("ipv6: Neigbor cace state timeout received\n");
+                ng_ndp_state_timeout((ng_ipv6_nc_t *)msg.content.ptr);
+                break;
+
             default:
                 break;
         }
@@ -411,8 +434,6 @@ static void _send(ng_pktsnip_t *pkt, bool prep_hdr)
     kernel_pid_t iface = KERNEL_PID_UNDEF;
     ng_pktsnip_t *ipv6, *payload;
     ng_ipv6_hdr_t *hdr;
-    ng_ipv6_nc_t *nc_entry;
-
     /* seize payload as temporary variable */
     payload = ng_pktbuf_start_write(pkt);
 
@@ -442,24 +463,14 @@ static void _send(ng_pktsnip_t *pkt, bool prep_hdr)
         _send_multicast(iface, pkt, ipv6, payload, prep_hdr);
     }
     else {
-        ng_ipv6_addr_t *next_hop = NULL;
+        uint8_t l2addr_len = NG_IPV6_NC_L2_ADDR_MAX;
+        uint8_t l2addr[l2addr_len];
 
-        next_hop = &hdr->dst;   /* TODO: next hop determination */
-
-        if (((nc_entry = ng_ipv6_nc_get(iface, next_hop)) == NULL) ||
-            !ng_ipv6_nc_is_reachable(nc_entry)) {
-            DEBUG("ipv6: No link layer address for next_hop %s found.\n",
-                  ng_ipv6_addr_to_str(addr_str, next_hop, sizeof(addr_str)));
-            ng_pktbuf_release(pkt);
-            return;
-        }
-        else {
-            iface = nc_entry->iface;
-        }
+        iface = ng_ndp_next_hop_l2addr(l2addr, &l2addr_len, iface, &hdr->dst,
+                                       pkt);
 
         if (iface == KERNEL_PID_UNDEF) {
-            DEBUG("ipv6: no interface for %s registered, dropping packet\n",
-                  ng_ipv6_addr_to_str(addr_str, next_hop, sizeof(addr_str)));
+            DEBUG("ipv6: error determining next hop's link layer address\n");
             ng_pktbuf_release(pkt);
             return;
         }
@@ -472,7 +483,7 @@ static void _send(ng_pktsnip_t *pkt, bool prep_hdr)
             }
         }
 
-        _send_unicast(iface, nc_entry->l2_addr, nc_entry->l2_addr_len, pkt);
+        _send_unicast(iface, l2addr, l2addr_len, pkt);
     }
 }
 

sys/net/network_layer/ng_ndp/Makefile

+include $(RIOTBASE)/Makefile.base

sys/shell/commands/sc_icmpv6_echo.c

@@ -23,6 +23,7 @@
 #include "byteorder.h"
 #include "net/ng_icmpv6.h"
 #include "net/ng_ipv6/addr.h"
+#include "net/ng_ipv6/nc.h"
 #include "net/ng_ipv6/hdr.h"
 #include "net/ng_netbase.h"
 #include "thread.h"
@@ -83,6 +84,7 @@ int _handle_reply(ng_pktsnip_t *pkt, uint64_t time)
                ng_ipv6_addr_to_str(ipv6_str, &(ipv6_hdr->src), sizeof(ipv6_str)),
                byteorder_ntohs(icmpv6_hdr->id), byteorder_ntohs(icmpv6_hdr->seq),
                ipv6_hdr->hl, time / MS_IN_USEC, time % MS_IN_USEC);
+        ng_ipv6_nc_still_reachable(&ipv6_hdr->src);
     }
     else {
         puts("error: unexpected parameters");