gnrc_sixlowpan_nd_border_router: initial import of border router behavior of 6LoWPAN-ND

Makefile.dep

@@ -64,6 +64,14 @@ ifneq (,$(filter gnrc_sixlowpan_router_default,$(USEMODULE)))
   USEMODULE += gnrc_sixlowpan_iphc
 endif
 
+ifneq (,$(filter gnrc_sixlowpan_border_router_default,$(USEMODULE)))
+  USEMODULE += gnrc_ipv6_router_default
+  USEMODULE += gnrc_sixlowpan_nd_border_router
+  USEMODULE += gnrc_sixlowpan_router
+  USEMODULE += gnrc_sixlowpan_frag
+  USEMODULE += gnrc_sixlowpan_iphc
+endif
+
 ifneq (,$(filter gnrc_sixlowpan_router,$(USEMODULE)))
   USEMODULE += gnrc_sixlowpan
 endif
@@ -89,6 +97,10 @@ ifneq (,$(filter gnrc_sixlowpan_ctx,$(USEMODULE)))
   USEMODULE += vtimer
 endif
 
+ifneq (,$(filter gnrc_sixlowpan_nd_border_router,$(USEMODULE)))
+  USEMODULE += gnrc_sixlowpan_nd_router
+endif
+
 ifneq (,$(filter gnrc_sixlowpan_nd_router,$(USEMODULE)))
   USEMODULE += gnrc_sixlowpan_nd
 endif

Makefile.pseudomodules

@@ -3,6 +3,8 @@ PSEUDOMODULES += gnrc_ipv6_default
 PSEUDOMODULES += gnrc_ipv6_router
 PSEUDOMODULES += gnrc_ipv6_router_default
 PSEUDOMODULES += gnrc_sixlowpan_default
+PSEUDOMODULES += gnrc_sixlowpan_border_router_default
+PSEUDOMODULES += gnrc_sixlowpan_nd_border_router
 PSEUDOMODULES += gnrc_sixlowpan_router
 PSEUDOMODULES += gnrc_sixlowpan_router_default
 PSEUDOMODULES += gnrc_pktbuf

doc/doxygen/riot.doxyfile

@@ -2005,6 +2005,7 @@ PREDEFINED             = DOXYGEN \
                          MODULE_GNRC_NDP_ROUTER \
                          MODULE_GNRC_SIXLOWPAN \
                          MODULE_GNRC_SIXLOWPAN_ND_ROUTER \
+                         MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER \
                          MODULE_GNRC_UDP
 
 

sys/include/net/gnrc/sixlowpan/nd.h

@@ -33,6 +33,7 @@
 #include "net/sixlowpan/nd.h"
 #include "timex.h"
 
+#include "net/gnrc/sixlowpan/nd/border_router.h"
 #include "net/gnrc/sixlowpan/nd/router.h"
 
 #ifdef __cplusplus
@@ -78,6 +79,16 @@ extern "C" {
 #define GNRC_SIXLOWPAN_ND_AR_LTIME          (15U)
 #endif
 
+/**
+ * @name    Border router constants
+ * @{
+ * @see     <a href="https://tools.ietf.org/html/rfc6775#section-9">
+ *              RFC 6775, section 9
+ *          </a>
+ */
+#define GNRC_SIXLOWPAN_ND_RTR_MIN_CTX_DELAY (300U)  /**< minimum delay between context change and
+                                                     *   stop of C=0 dissimination in seconds */
+/** @} */
 /**
  * @name    Host constants
  * @{

sys/include/net/gnrc/sixlowpan/nd/border_router.h

@@ -0,0 +1,43 @@
+/*
+ * 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    gnrc_sixlowpan_nd_border_router Border router part of 6LoWPAN-ND
+ * @ingroup     gnrc_sixlowpan_nd
+ * @brief       Border router part of 6LoWPAN-ND
+ * @{
+ *
+ * @file
+ * @brief   Border router definitions for 6LoWPAN.
+ *
+ * @author  Martine Lenders <mlenders@inf.fu-berlin.de>
+ */
+#ifndef GNRC_SIXLOWPAN_BORDER_ROUTER_H_
+#define GNRC_SIXLOWPAN_BORDER_ROUTER_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Default lifetime in minutes for 6LoWPAN border router information.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc6775#section-4.3">
+ *          RFC 6775, section 4.3
+ *      </a>
+ */
+#ifndef GNRC_SIXLOWPAN_ND_BORDER_ROUTER_DEFAULT_LTIME
+#define GNRC_SIXLOWPAN_ND_BORDER_ROUTER_DEFAULT_LTIME   (10000U)
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* GNRC_SIXLOWPAN_BORDER_ROUTER_H_ */
+/** @} */

sys/include/net/gnrc/sixlowpan/nd/router.h

@@ -156,6 +156,71 @@ bool gnrc_sixlowpan_nd_router_abr_older(sixlowpan_nd_opt_abr_t *abr_opt);
  */
 void gnrc_sixlowpan_nd_router_abr_remove(gnrc_sixlowpan_nd_router_abr_t *abr);
 
+#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
+/**
+ * @brief   Makes this node a new border router.
+ *
+ * @per addr != NULL
+ *
+ * @param[in] addr  The local address to use in the ABROs
+ * @param[in] ltime The lifetime to advertise in the ABROs. 0 assumes a default value of
+ *                  @ref GNRC_SIXLOWPAN_ND_BORDER_ROUTER_DEFAULT_LTIME
+ *
+ * @return  The new border router object.
+ * @return  NULL, on error.
+ */
+gnrc_sixlowpan_nd_router_abr_t *gnrc_sixlowpan_nd_router_abr_create(ipv6_addr_t *addr,
+                                                                    unsigned int ltime);
+
+/**
+ * @brief   Adds a prefix for this border router to manage.
+ *
+ * @pre iface != NULL && prefix != NULL
+ *
+ * @param[in] abr       The local border router
+ * @param[in] iface     The IPv6 interface the prefix was added to.
+ * @param[in] prefix    The prefix.
+ *
+ * @return  0, on success
+ * @return  -ENOMEM, if no space for the new prefix is available.
+ * @return  -ENOENT, if @p abr is not registered.
+ */
+int gnrc_sixlowpan_nd_router_abr_add_prf(gnrc_sixlowpan_nd_router_abr_t* abr,
+                                         gnrc_ipv6_netif_t *iface, gnrc_ipv6_netif_addr_t *prefix);
+
+/**
+ * @brief   Removes a prefix from this border router.
+ *
+ * @param[in] abr       The local border router
+ * @param[in] iface     The IPv6 interface the prefix was added to.
+ * @param[in] prefix    The prefix.
+ */
+void gnrc_sixlowpan_nd_router_abr_rem_prf(gnrc_sixlowpan_nd_router_abr_t *abr,
+                                          gnrc_ipv6_netif_t *iface, gnrc_ipv6_netif_addr_t *prefix);
+
+/**
+ * @brief   Adds a context for this border router to manage.
+ *
+ * @param[in] abr       The local border router
+ * @param[in] ctx       The context to be add.
+ *
+ * @return  0, on success
+ * @return  -EINVAL, if @p ctx is greater than 15.
+ * @return  -ENOENT, if @p abr is not registered.
+ */
+int gnrc_sixlowpan_nd_router_abr_add_ctx(gnrc_sixlowpan_nd_router_abr_t *abr, uint8_t cid);
+
+/**
+ * @brief   Removes a context from this border router.
+ *
+ * @param[in] abr       The local border router
+ * @param[in] ctx       The context to be remove.
+ */
+void gnrc_sixlowpan_nd_router_abr_rem_ctx(gnrc_sixlowpan_nd_router_abr_t *abr, uint8_t cid);
+#else
+#define gnrc_sixlowpan_nd_router_abr_create(addr, ltime)    (NULL)
+#endif
+
 #ifdef __cplusplus
 }
 #endif

sys/net/gnrc/network_layer/ipv6/netif/gnrc_ipv6_netif.c

@@ -111,6 +111,12 @@ static ipv6_addr_t *_add_addr_to_entry(gnrc_ipv6_netif_t *entry, const ipv6_addr
                 gnrc_ndp_router_retrans_rtr_adv(entry);
                 mutex_lock(&entry->mutex);      /* relock mutex */
             }
+#endif
+#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
+            gnrc_sixlowpan_nd_router_abr_t *abr = gnrc_sixlowpan_nd_router_abr_get();
+            if (gnrc_sixlowpan_nd_router_abr_add_prf(abr, entry, tmp_addr) < 0) {
+                DEBUG("ipv6_netif: error adding prefix to 6LoWPAN-ND management\n");
+            }
 #endif
         }
         else {
@@ -303,6 +309,10 @@ static void _remove_addr_from_entry(gnrc_ipv6_netif_t *entry, ipv6_addr_t *addr)
                 return;
             }
 #endif
+#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
+            gnrc_sixlowpan_nd_router_abr_t *abr = gnrc_sixlowpan_nd_router_abr_get();
+            gnrc_sixlowpan_nd_router_abr_rem_prf(abr, entry, &entry->addrs[i]);
+#endif
 
             mutex_unlock(&entry->mutex);
             return;
@@ -752,6 +762,9 @@ void gnrc_ipv6_netif_init_by_dev(void)
 {
     kernel_pid_t ifs[GNRC_NETIF_NUMOF];
     size_t ifnum = gnrc_netif_get(ifs);
+#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
+    bool abr_init = false;
+#endif
 
     for (size_t i = 0; i < ifnum; i++) {
         ipv6_addr_t addr;
@@ -826,6 +839,14 @@ void gnrc_ipv6_netif_init_by_dev(void)
 #endif
 #ifdef MODULE_GNRC_SIXLOWPAN_ND
         if (ipv6_if->flags & GNRC_IPV6_NETIF_FLAGS_SIXLOWPAN) {
+#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
+            /* first interface wins */
+            if (!abr_init) {
+                gnrc_sixlowpan_nd_router_abr_create(&addr, 0);
+                gnrc_ipv6_netif_set_rtr_adv(ipv6_if, true);
+                abr_init = true;
+            }
+#endif
             gnrc_sixlowpan_nd_init(ipv6_if);
             continue;   /* skip gnrc_ndp_host_init() */
         }

sys/net/gnrc/network_layer/sixlowpan/ctx/gnrc_sixlowpan_ctx.c

@@ -127,7 +127,6 @@ gnrc_sixlowpan_ctx_t *gnrc_sixlowpan_ctx_update(uint8_t id, const ipv6_addr_t *p
     _ctx_inval_times[id] = ltime + _current_minute();
 
     mutex_unlock(&_ctx_mutex);
-
     return &(_ctxs[id]);
 }
 

sys/net/gnrc/network_layer/sixlowpan/nd/router/gnrc_sixlowpan_nd_router.c

@@ -95,6 +95,17 @@ static void _add_ctx(gnrc_sixlowpan_nd_router_abr_t *abr, sixlowpan_nd_opt_6ctx_
     bf_set(abr->ctxs, sixlowpan_nd_opt_6ctx_get_cid(ctx_opt));
 }
 
+#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
+static inline bool _is_me(ipv6_addr_t *addr)
+{
+    ipv6_addr_t *res;
+
+    return (gnrc_ipv6_netif_find_by_addr(&res, addr) != KERNEL_PID_UNDEF);
+}
+#else
+#define _is_me(ignore)  (false)
+#endif
+
 gnrc_sixlowpan_nd_router_abr_t *gnrc_sixlowpan_nd_router_abr_get(void)
 {
     if (ipv6_addr_is_unspecified(&_abrs[0].addr)) {
@@ -113,6 +124,10 @@ bool gnrc_sixlowpan_nd_router_abr_older(sixlowpan_nd_opt_abr_t *abr_opt)
         return true;
     }
 
+    if (_is_me(&abr_opt->braddr)) {
+        return false;
+    }
+
     abr = _get_abr(&abr_opt->braddr);
 
     if (abr == NULL) {
@@ -155,9 +170,11 @@ void gnrc_sixlowpan_nd_opt_abr_handle(kernel_pid_t iface, ndp_rtr_adv_t *rtr_adv
     gnrc_sixlowpan_nd_router_abr_t *abr;
     timex_t t = { 0, 0 };
 
+    if (_is_me(&abr_opt->braddr)) {
+        return;
+    }
     /* validity and version was checked in previously called
      * gnrc_sixlowpan_nd_router_abr_older() */
-
     abr = _get_abr(&abr_opt->braddr);
 
     if (abr == NULL) {
@@ -167,7 +184,7 @@ void gnrc_sixlowpan_nd_opt_abr_handle(kernel_pid_t iface, ndp_rtr_adv_t *rtr_adv
     abr->ltime = byteorder_ntohs(abr_opt->ltime);
 
     if (abr->ltime == 0) {
-        gnrc_sixlowpan_nd_router_abr_remove(abr);
+        abr->ltime = GNRC_SIXLOWPAN_ND_BORDER_ROUTER_DEFAULT_LTIME;
         return;
     }
 
@@ -242,4 +259,99 @@ gnrc_pktsnip_t *gnrc_sixlowpan_nd_opt_abr_build(uint32_t version, uint16_t ltime
     return pkt;
 }
 
+#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
+gnrc_sixlowpan_nd_router_abr_t *gnrc_sixlowpan_nd_router_abr_create(ipv6_addr_t *addr,
+                                                                    unsigned int ltime)
+{
+    assert(addr != NULL);
+    gnrc_sixlowpan_nd_router_abr_t *abr = _get_abr(addr);
+    if (abr == NULL) {
+        return NULL;
+    }
+    /* TODO: store and get this somewhere stable */
+    abr->version = 0;
+    abr->ltime = (uint16_t)ltime;
+    abr->addr.u64[0] = addr->u64[0];
+    abr->addr.u64[1] = addr->u64[1];
+    memset(abr->ctxs, 0, sizeof(abr->ctxs));
+    abr->prfs = NULL;
+    return abr;
+}
+
+int gnrc_sixlowpan_nd_router_abr_add_prf(gnrc_sixlowpan_nd_router_abr_t* abr,
+                                         gnrc_ipv6_netif_t *iface, gnrc_ipv6_netif_addr_t *prefix)
+{
+    assert((iface != NULL) && (prefix != NULL));
+    gnrc_sixlowpan_nd_router_prf_t *prf_ent;
+    if ((abr < _abrs) || (abr > (_abrs + GNRC_SIXLOWPAN_ND_ROUTER_ABR_NUMOF))) {
+        return -ENOENT;
+    }
+    prf_ent = _get_free_prefix(&prefix->addr, prefix->prefix_len);
+    if (prf_ent == NULL) {
+        return -ENOMEM;
+    }
+    prf_ent->iface = iface;
+    prf_ent->prefix = prefix;
+    LL_PREPEND(abr->prfs, prf_ent);
+    abr->version++; /* TODO: store somewhere stable */
+    return 0;
+}
+
+
+void gnrc_sixlowpan_nd_router_abr_rem_prf(gnrc_sixlowpan_nd_router_abr_t *abr,
+                                          gnrc_ipv6_netif_t *iface, gnrc_ipv6_netif_addr_t *prefix)
+{
+    assert((iface != NULL) && (prefix != NULL));
+    gnrc_sixlowpan_nd_router_prf_t *prf_ent = abr->prfs, *prev = NULL;
+    if ((abr < _abrs) || (abr > (_abrs + GNRC_SIXLOWPAN_ND_ROUTER_ABR_NUMOF))) {
+        return;
+    }
+    while (prf_ent) {
+        if (prf_ent->prefix == prefix) {
+            if (prev == NULL) {
+                abr->prfs = prf_ent->next;
+            }
+            else {
+                prev->next = prf_ent->next;
+            }
+            prf_ent->next = NULL;
+            prf_ent->iface = NULL;
+            prf_ent->prefix = NULL;
+            abr->version++; /* TODO: store somewhere stable */
+            break;
+        }
+        prev = prf_ent;
+        prf_ent = prf_ent->next;
+    }
+}
+
+int gnrc_sixlowpan_nd_router_abr_add_ctx(gnrc_sixlowpan_nd_router_abr_t *abr, uint8_t cid)
+{
+    if ((abr < _abrs) || (abr > (_abrs + GNRC_SIXLOWPAN_ND_ROUTER_ABR_NUMOF))) {
+        return -ENOENT;
+    }
+    if (cid >= GNRC_SIXLOWPAN_CTX_SIZE) {
+        return -EINVAL;
+    }
+    if (bf_isset(abr->ctxs, cid)) {
+        return -EADDRINUSE;
+    }
+    bf_set(abr->ctxs, cid);
+    abr->version++; /* TODO: store somewhere stable */
+    return 0;
+}
+
+void gnrc_sixlowpan_nd_router_abr_rem_ctx(gnrc_sixlowpan_nd_router_abr_t *abr, uint8_t cid)
+{
+    if ((abr < _abrs) || (abr > (_abrs + GNRC_SIXLOWPAN_ND_ROUTER_ABR_NUMOF))) {
+        return;
+    }
+    if (cid >= GNRC_SIXLOWPAN_CTX_SIZE) {
+        return;
+    }
+    bf_unset(abr->ctxs, cid);
+    abr->version++; /* TODO: store somewhere stable */
+    return;
+}
+#endif
 /** @} */