ng_rpl: auto address configuration

sys/include/net/ng_rpl.h

@@ -209,6 +209,16 @@ static inline bool NG_RPL_COUNTER_GREATER_THAN(uint8_t A, uint8_t B)
  */
 #define NG_RPL_LIFETIME_STEP (2)
 
+/**
+ * @brief Default prefix length for the DODAG id
+ */
+#define NG_RPL_DEFAULT_PREFIX_LEN   (64)
+
+/**
+ * @brief Default prefix valid and preferred time for the DODAG id
+ */
+#define NG_RPL_DEFAULT_PREFIX_LIFETIME  (0xFFFFFFFF)
+
 /**
  * @brief A DODAG can be grounded or floating
  * @see <a href="https://tools.ietf.org/html/rfc6550#section-3.2.4">

sys/include/net/ng_rpl/structs.h

@@ -147,6 +147,23 @@ typedef struct __attribute__((packed)) {
     uint8_t path_lifetime;      /**< lifetime of routes */
 } ng_rpl_opt_transit_t;
 
+/**
+ * @brief Prefix Information Option
+ * @see <a href="https://tools.ietf.org/html/rfc6550#section-6.7.10">
+ *          RFC6550, section 6.7.10, Prefix Information
+ *      </a>
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t type;               /**< option type */
+    uint8_t length;             /**< option length without the first two bytes */
+    uint8_t prefix_len;         /**< prefix length */
+    uint8_t LAR_flags;          /**< flags and resereved */
+    uint32_t valid_lifetime;    /**< valid lifetime */
+    uint32_t pref_lifetime;     /**< preferred lifetime */
+    uint32_t reserved;          /**< reserved */
+    ipv6_addr_t prefix;         /**< prefix used for Stateless Address Autoconfiguration */
+} ng_rpl_opt_prefix_info_t;
+
 typedef struct ng_rpl_dodag ng_rpl_dodag_t;
 typedef struct ng_rpl_parent ng_rpl_parent_t;
 
@@ -201,6 +218,9 @@ struct ng_rpl_dodag {
     ng_rpl_dodag_t *next;           /**< pointer to the next dodag */
     ng_rpl_parent_t *parents;       /**< pointer to the parents list of this DODAG */
     ipv6_addr_t dodag_id;           /**< id of the DODAG */
+    uint8_t prefix_len;             /**< length of the prefix for the DODAG id */
+    uint32_t addr_preferred;        /**< time in seconds the DODAG id is preferred */
+    uint32_t addr_valid;            /**< time in seconds the DODAG id is valid */
     uint8_t state;                  /**< 0 for unused, 1 for used */
     uint8_t dtsn;                   /**< DAO Trigger Sequence Number */
     uint8_t prf;                    /**< preferred flag */

sys/net/routing/ng_rpl/ng_rpl.c

@@ -106,6 +106,7 @@ static ng_rpl_dodag_t *_root_dodag_init(uint8_t instance_id, ipv6_addr_t *dodag_
     }
 
     ipv6_addr_t *configured_addr;
+    ng_ipv6_netif_addr_t *netif_addr = NULL;
     ng_rpl_instance_t *inst = NULL;
     ng_rpl_dodag_t *dodag = NULL;
 
@@ -120,6 +121,12 @@ static ng_rpl_dodag_t *_root_dodag_init(uint8_t instance_id, ipv6_addr_t *dodag_
         return NULL;
     }
 
+    if ((netif_addr = ng_ipv6_netif_addr_get(configured_addr)) == NULL) {
+        DEBUG("RPL: no netif address found for %s\n", ipv6_addr_to_str(addr_str, configured_addr,
+                sizeof(addr_str)));
+        return NULL;
+    }
+
     if (ng_rpl_instance_add(instance_id, &inst)) {
         inst->of = (ng_rpl_of_t *) ng_rpl_get_of_for_ocp(NG_RPL_DEFAULT_OCP);
         inst->mop = mop;
@@ -141,6 +148,10 @@ static ng_rpl_dodag_t *_root_dodag_init(uint8_t instance_id, ipv6_addr_t *dodag_
         return NULL;
     }
 
+    dodag->prefix_len = netif_addr->prefix_len;
+    dodag->addr_preferred = netif_addr->preferred;
+    dodag->addr_valid = netif_addr->valid;
+
     return dodag;
 }
 

sys/net/routing/ng_rpl/ng_rpl_control_messages.c

@@ -19,6 +19,7 @@
 #include "net/ng_icmpv6.h"
 #include "net/ng_rpl.h"
 #include "inet_ntop.h"
+#include "net/eui64.h"
 
 #define ENABLE_DEBUG    (0)
 #include "debug.h"
@@ -30,8 +31,10 @@ static char addr_str[IPV6_ADDR_MAX_STR_LEN];
 #define NG_RPL_GROUNDED_SHIFT           (7)
 #define NG_RPL_MOP_SHIFT                (3)
 #define NG_RPL_OPT_DODAG_CONF_LEN       (14)
+#define NG_RPL_OPT_PREFIX_INFO_LEN      (30)
 #define NG_RPL_SHIFTED_MOP_MASK         (0x7)
 #define NG_RPL_PRF_MASK                 (0x7)
+#define NG_RPL_PREFIX_AUTO_ADDRESS_BIT  (1 << 6)
 
 void _ng_rpl_send(ng_pktsnip_t *pkt, ipv6_addr_t *src, ipv6_addr_t *dst,
         ipv6_addr_t *dodag_id)
@@ -100,6 +103,7 @@ void ng_rpl_send_DIO(ng_rpl_dodag_t *dodag, ipv6_addr_t *destination)
 
     if ((dodag->dodag_conf_counter % 3) == 0) {
         size += sizeof(ng_rpl_opt_dodag_conf_t);
+        size += sizeof(ng_rpl_opt_prefix_info_t);
     }
 
     if ((pkt = ng_icmpv6_build(NULL, ICMPV6_RPL_CTRL, NG_RPL_ICMPV6_CODE_DIO, size)) == NULL) {
@@ -137,6 +141,21 @@ void ng_rpl_send_DIO(ng_rpl_dodag_t *dodag, ipv6_addr_t *destination)
         dodag_conf->reserved = 0;
         dodag_conf->default_lifetime = dodag->default_lifetime;
         dodag_conf->lifetime_unit = byteorder_htons(dodag->lifetime_unit);
+        pos += sizeof(*dodag_conf);
+
+        ng_rpl_opt_prefix_info_t *prefix_info;
+        prefix_info = (ng_rpl_opt_prefix_info_t *) pos;
+        prefix_info->type = NG_RPL_OPT_PREFIX_INFO;
+        prefix_info->length = NG_RPL_OPT_PREFIX_INFO_LEN;
+        /* auto-address configuration */
+        prefix_info->LAR_flags = NG_RPL_PREFIX_AUTO_ADDRESS_BIT;
+        prefix_info->valid_lifetime = dodag->addr_valid;
+        prefix_info->pref_lifetime = dodag->addr_preferred;
+        prefix_info->prefix_len = dodag->prefix_len;
+        prefix_info->reserved = 0;
+
+        memset(&prefix_info->prefix, 0, sizeof(prefix_info->prefix));
+        ipv6_addr_init_prefix(&prefix_info->prefix, &dodag->dodag_id, dodag->prefix_len);
     }
 
     dodag->dodag_conf_counter++;
@@ -198,6 +217,7 @@ bool _parse_options(int msg_type, ng_rpl_dodag_t *dodag, ng_rpl_opt_t *opt, uint
 {
     uint16_t l = 0;
     ng_rpl_opt_target_t *first_target = NULL;
+    eui64_t iid;
     while(l < len) {
         if ((opt->type != NG_RPL_OPT_PAD1) && (len < opt->length + sizeof(ng_rpl_opt_t) + l)) {
             /* return false to delete the dodag,
@@ -243,6 +263,25 @@ bool _parse_options(int msg_type, ng_rpl_dodag_t *dodag, ng_rpl_opt_t *opt, uint
                 dodag->trickle.k = dodag->dio_redun;
                 break;
             }
+            case (NG_RPL_OPT_PREFIX_INFO): {
+                if (msg_type != NG_RPL_ICMPV6_CODE_DIO) {
+                    DEBUG("RPL: Ignore Prefix Information DIO option\n");
+                    return true;
+                }
+                DEBUG("RPL: Prefix Information DIO option parsed\n");
+                ng_rpl_opt_prefix_info_t *pi = (ng_rpl_opt_prefix_info_t *) opt;
+                ipv6_addr_t all_RPL_nodes = NG_IPV6_ADDR_ALL_RPL_NODES;
+                kernel_pid_t if_id = ng_ipv6_netif_find_by_addr(NULL, &all_RPL_nodes);
+                /* check for the auto address-configuration flag */
+                if ((ng_netapi_get(if_id, NETOPT_IPV6_IID, 0, &iid, sizeof(eui64_t)) < 0) &&
+                        !(pi->LAR_flags & NG_RPL_PREFIX_AUTO_ADDRESS_BIT)) {
+                    break;
+                }
+                ipv6_addr_set_aiid(&pi->prefix, iid.uint8);
+                ng_ipv6_netif_add_addr(if_id, &pi->prefix, pi->prefix_len, 0);
+
+                break;
+            }
             case (NG_RPL_OPT_TARGET): {
                 if (msg_type != NG_RPL_ICMPV6_CODE_DAO) {
                     DEBUG("RPL: Ignore RPL TARGET DAO option\n");

sys/net/routing/ng_rpl/ng_rpl_dodag.c

@@ -19,6 +19,7 @@
 #include "net/ng_rpl/dodag.h"
 #include "net/ng_rpl/structs.h"
 #include "utlist.h"
+#include "net/ng_rpl.h"
 
 #define ENABLE_DEBUG    (0)
 #include "debug.h"
@@ -135,6 +136,9 @@ bool ng_rpl_dodag_add(ng_rpl_instance_t *instance, ipv6_addr_t *dodag_id, ng_rpl
         LL_APPEND(instance->dodags, *dodag);
         (*dodag)->state = 1;
         (*dodag)->dodag_id = *dodag_id;
+        (*dodag)->prefix_len = NG_RPL_DEFAULT_PREFIX_LEN;
+        (*dodag)->addr_preferred = NG_RPL_DEFAULT_PREFIX_LIFETIME;
+        (*dodag)->addr_valid = NG_RPL_DEFAULT_PREFIX_LIFETIME;
         (*dodag)->my_rank = NG_RPL_INFINITE_RANK;
         (*dodag)->trickle.callback.func = &rpl_trickle_send_dio;
         (*dodag)->trickle.callback.args = *dodag;