From 34b8313fb6d07b38e9869b657b98ecc8b787f53a Mon Sep 17 00:00:00 2001
From: joxe <joxe>
Date: Tue, 25 May 2010 19:19:43 +0000
Subject: [PATCH] added experimental support for disseminating autoconf prefix
 via DIO suboption

---
 core/net/rpl/rpl-dag.c   | 23 +++++++++++++++-
 core/net/rpl/rpl-icmp6.c | 57 +++++++++++++++++++++++++++++++++++++---
 core/net/rpl/rpl.h       | 24 ++++++++++-------
 3 files changed, 89 insertions(+), 15 deletions(-)

diff --git a/core/net/rpl/rpl-dag.c b/core/net/rpl/rpl-dag.c
index 73f76b323..d2b605c9f 100644
--- a/core/net/rpl/rpl-dag.c
+++ b/core/net/rpl/rpl-dag.c
@@ -32,7 +32,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: rpl-dag.c,v 1.7 2010/05/24 16:38:56 nvt-se Exp $
+ * $Id: rpl-dag.c,v 1.8 2010/05/25 19:19:43 joxe Exp $
  */
 /**
  * \file
@@ -44,6 +44,7 @@
 #include "net/rpl/rpl.h"
 
 #include "net/uip.h"
+#include "net/uip-nd6.h"
 #include "net/rime/ctimer.h"
 #include "lib/list.h"
 #include "lib/memb.h"
@@ -162,6 +163,22 @@ rpl_set_root(uip_ipaddr_t *dag_id)
 }
 /************************************************************************/
 int
+rpl_set_prefix(rpl_dag_t *dag, uip_ipaddr_t *prefix, int len) {
+  if(len <= 128) {
+    memset(&dag->destination_prefix.prefix, 0, 16);
+    memcpy(&dag->destination_prefix.prefix, prefix, (len + 7)/ 8);
+    dag->destination_prefix.length = len;
+    /* Note: this is an experiment to see if RPL can be used for
+       prefix-assignment for RPL nodes - this flag is originally
+       intended for Router Advertisements */
+    dag->destination_prefix.preference = UIP_ND6_RA_FLAG_AUTONOMOUS;
+    PRINTF("RPL: Prefix set - will announce this in DIOs\n");
+    return 0;
+  }
+  return -1;
+}
+/************************************************************************/
+int
 rpl_set_default_route(rpl_dag_t *dag, uip_ipaddr_t *from)
 {
   if(dag->def_route != NULL) {
@@ -423,6 +440,10 @@ join_dag(uip_ipaddr_t *from, rpl_dio_t *dio)
 
   memcpy(&dag->dag_id, &dio->dag_id, sizeof(dio->dag_id));
 
+  /* copy prefix information into the dag */
+  memcpy(&dag->destination_prefix, &dio->destination_prefix,
+         sizeof(rpl_prefix_t));
+
   rpl_join_dag(dag);
 
   PRINTF("RPL: Joined DAG with instance ID %u, rank %hu, DAG ID ",
diff --git a/core/net/rpl/rpl-icmp6.c b/core/net/rpl/rpl-icmp6.c
index 342a3fdd7..72147480d 100644
--- a/core/net/rpl/rpl-icmp6.c
+++ b/core/net/rpl/rpl-icmp6.c
@@ -33,7 +33,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: rpl-icmp6.c,v 1.9 2010/05/24 16:38:56 nvt-se Exp $
+ * $Id: rpl-icmp6.c,v 1.10 2010/05/25 19:19:43 joxe Exp $
  */
 /**
  * \file
@@ -164,7 +164,6 @@ dio_input(void)
   uint8_t subopt_type;
   int i;
   int len;
-  rpl_prefix_t prefix;
   uip_ipaddr_t from;
   uip_ds6_nbr_t *nbr;
 
@@ -237,7 +236,37 @@ dio_input(void)
         PRINTF("RPL: Invalid destination prefix option, len = %d\n", len);
         return;
       }
-      prefix.preference = (buffer[3] >> 3) & 0x3;
+      /* prebference is both preference and flags for now */
+      dio.destination_prefix.preference = buffer[i + 3];
+      dio.destination_prefix.lifetime = get32(buffer, i + 4);
+      dio.destination_prefix.length = buffer[i + 8];
+      if(((dio.destination_prefix.length + 7)/ 8) + 9 <= len &&
+         dio.destination_prefix.length <= 128) {
+        PRINTF("RPL: Copying destination prefix\n");
+        memcpy(&dio.destination_prefix.prefix, &buffer[i + 9],
+               (dio.destination_prefix.length + 7) / 8);
+
+        /* NOTE: This is a test for adding autoconf prefix in RPL via  */
+        /* a destination prefix - this use one reserved flag bit       */
+        /* This should not be made until RPL decides to join the DAG   */
+        /* And not if there already is a global address configured for */
+        /* the specific DAG */
+        if((dio.destination_prefix.preference & UIP_ND6_RA_FLAG_AUTONOMOUS)) {
+          uip_ipaddr_t ipaddr;
+          memcpy(&ipaddr, &dio.destination_prefix.prefix,
+                 (dio.destination_prefix.length + 7) / 8);
+          uip_ds6_set_addr_iid(&ipaddr, &uip_lladdr);
+          if(uip_ds6_addr_lookup(&ipaddr) == NULL) {
+            PRINTF("RPL: adding global IP address ");
+            PRINT6ADDR(&ipaddr);
+            PRINTF("\n");
+            uip_ds6_addr_add(&ipaddr, 0, ADDR_AUTOCONF);
+          }
+        }
+      } else {
+        PRINTF("RPL: Invalid destination prefix option, len = %d\n", len);
+      }
+
       break;
     case RPL_DIO_SUBOPT_DAG_CONF:
       dio.dag_intdoubl = buffer[i + 3];
@@ -309,6 +338,26 @@ dio_output(rpl_dag_t *dag, uip_ipaddr_t *uc_addr)
   buffer[pos++] = dag->max_rankinc;
   buffer[pos++] = dag->min_hoprankinc;
 
+  /* if prefix length > 0 then we have a prefix to send! */
+  if(dag->destination_prefix.length > 0) {
+    buffer[pos++] = RPL_DIO_SUBOPT_DEST_PREFIX;
+    buffer[pos++] = 0;
+    buffer[pos++] = (dag->destination_prefix.length + 7)/ 8 + 9;
+    buffer[pos++] = dag->destination_prefix.preference;
+    set32(buffer, pos, dag->destination_prefix.lifetime);
+    pos += 4;
+    buffer[pos++] = dag->destination_prefix.length;
+    memcpy(&buffer[pos], &(dag->destination_prefix.prefix),
+           (dag->destination_prefix.length + 7)/ 8);
+    pos += (dag->destination_prefix.length + 7)/ 8;
+    PRINTF("RPL: Sending prefix info in DIO ");
+    PRINT6ADDR(&dag->destination_prefix.prefix);
+    PRINTF("\n");
+  } else {
+    PRINTF("RPL: No prefix to announce. len:%d\n",
+           dag->destination_prefix.length);
+  }
+
   /* buffer[len++] = RPL_DIO_SUBOPT_PAD1; */
 
   /* Unicast requests get unicast replies! */
@@ -318,7 +367,7 @@ dio_output(rpl_dag_t *dag, uip_ipaddr_t *uc_addr)
     uip_create_linklocal_allrouters_mcast(&addr);
     uip_icmp6_send(&addr, ICMP6_RPL, RPL_CODE_DIO, pos);
   } else {
-    PRINTF("RPL: Sending unicast-DIO with rank %u to ", 
+    PRINTF("RPL: Sending unicast-DIO with rank %u to ",
 	(unsigned)dag->rank);
     PRINT6ADDR(uc_addr);
     PRINTF("\n");
diff --git a/core/net/rpl/rpl.h b/core/net/rpl/rpl.h
index 99018cca8..52da38f5b 100644
--- a/core/net/rpl/rpl.h
+++ b/core/net/rpl/rpl.h
@@ -30,7 +30,7 @@
  *
  * Author: Joakim Eriksson, Nicolas Tsiftes
  *
- * $Id: rpl.h,v 1.2 2010/04/30 15:03:55 nvt-se Exp $
+ * $Id: rpl.h,v 1.3 2010/05/25 19:19:43 joxe Exp $
  */
 
 #ifndef RPL_H
@@ -146,6 +146,16 @@ struct rpl_of {
 
 typedef struct rpl_of rpl_of_t;
 
+/* RPL DIO prefix suboption */
+struct rpl_prefix {
+  uip_ipaddr_t prefix;
+  uint32_t lifetime;
+  uint8_t length;
+  uint8_t preference;
+};
+
+typedef struct rpl_prefix rpl_prefix_t;
+
 /* Logical representation of a DAG Information Object (DIO.) */
 struct rpl_dio {
   uip_ipaddr_t dag_id;
@@ -163,19 +173,11 @@ struct rpl_dio {
   uint8_t dag_redund;
   uint8_t dag_max_rankinc;
   uint8_t dag_min_hoprankinc;
+  rpl_prefix_t destination_prefix;
 };
 
 typedef struct rpl_dio rpl_dio_t;
 
-struct rpl_prefix {
-  uip_ipaddr_t prefix;
-  uint32_t lifetime;
-  uint8_t length;
-  uint8_t preference;
-};
-
-typedef struct rpl_prefix rpl_prefix_t;
-
 /* Directed Acyclic Graph */
 struct rpl_dag {
   /* DAG configuration */
@@ -213,6 +215,7 @@ struct rpl_dag {
   rpl_neighbor_t *best_parent;
   void *neighbor_list;
   list_t neighbors;
+  rpl_prefix_t destination_prefix;
 };
 
 typedef struct rpl_dag rpl_dag_t;
@@ -236,6 +239,7 @@ void uip_rpl_input(void);
 
 /* RPL logic functions. */
 int rpl_set_root(uip_ipaddr_t *);
+int rpl_set_prefix(rpl_dag_t *dag, uip_ipaddr_t *prefix, int len);
 int rpl_repair_dag(rpl_dag_t *dag);
 int rpl_set_default_route(rpl_dag_t *dag, uip_ipaddr_t *from);
 void rpl_process_dio(uip_ipaddr_t *, rpl_dio_t *);