ng_ipv6_ext: add routing header parsing

sys/Makefile

@@ -77,6 +77,9 @@ endif
 ifneq (,$(filter ng_ipv6_ext,$(USEMODULE)))
     DIRS += net/network_layer/ng_ipv6/ext
 endif
+ifneq (,$(filter ng_ipv6_ext_rh,$(USEMODULE)))
+    DIRS += net/network_layer/ng_ipv6/ext/rh
+endif
 ifneq (,$(filter ng_ipv6_hdr,$(USEMODULE)))
     DIRS += net/network_layer/ng_ipv6/hdr
 endif

sys/include/net/ng_ipv6/ext.h

@@ -32,6 +32,8 @@
 #include "kernel_types.h"
 #include "net/ng_pkt.h"
 
+#include "net/ng_ipv6/ext/rh.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif

sys/include/net/ng_ipv6/ext/rh.h

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2015 Martine Lenders <[email protected]>
+ *
+ * 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_ipv6_ext_rh  IPv6 routing header extension
+ * @ingroup     net_ng_ipv6_ext
+ * @brief       Implementation of IPv6 routing header extension.
+ * @{
+ *
+ * @file
+ * @brief   Routing extension header definitions.
+ *
+ * @author  Martine Lenders <[email protected]>
+ */
+#ifndef NG_IPV6_EXT_RH_H_
+#define NG_IPV6_EXT_RH_H_
+
+#include "net/ng_ipv6/addr.h"
+#include "net/ng_ipv6/hdr.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   IPv6 routing extension header.
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc2460#section-4.4">
+ *          RFC 2460, section 4.4
+ *      </a>
+ *
+ * @extends ng_ipv6_ext_t
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t nh;         /**< next header */
+    uint8_t len;        /**< length in 8 octets without first octet */
+    uint8_t type;       /**< identifier of a particular routing header type */
+    uint8_t seg_left;   /**< number of route segments remaining */
+} ng_ipv6_ext_rh_t;
+
+/**
+ * @brief   Extract next hop from the routing header of an IPv6 packet.
+ *
+ * @param[in] ipv6      An IPv6 packet.
+ *
+ * @return  next hop on success, on success
+ * @return  NULL, if not found.
+ */
+ng_ipv6_addr_t *ng_ipv6_ext_rh_next_hop(ng_ipv6_hdr_t *ipv6);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NG_IPV6_EXT_RH_H_ */
+/** @} */

sys/net/network_layer/ng_ipv6/ext/rh/Makefile

@@ -0,0 +1,3 @@
+MODULE = ng_ipv6_ext_rh
+
+include $(RIOTBASE)/Makefile.base

sys/net/network_layer/ng_ipv6/ext/rh/ng_ipv6_ext_rh.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2015 Martine Lenders <[email protected]>
+ *
+ * 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.
+ */
+
+/**
+ * @{
+ *
+ * @file
+ */
+
+#include <stdbool.h>
+
+#include "net/ng_protnum.h"
+#include "net/ng_rpl/srh.h"
+#include "net/ng_ipv6/ext/rh.h"
+
+ng_ipv6_addr_t *ng_ipv6_ext_rh_next_hop(ng_ipv6_hdr_t *ipv6)
+{
+    ng_ipv6_ext_rh_t *ext = (ng_ipv6_ext_rh_t *)(ipv6 + 1);
+    bool c = true;
+
+    while (c) {
+        switch (ext->type) {
+            case NG_PROTNUM_IPV6_EXT_HOPOPT:
+            case NG_PROTNUM_IPV6_EXT_DST:
+            case NG_PROTNUM_IPV6_EXT_FRAG:
+            case NG_PROTNUM_IPV6_EXT_AH:
+            case NG_PROTNUM_IPV6_EXT_ESP:
+            case NG_PROTNUM_IPV6_EXT_MOB:
+                ext = (ng_ipv6_ext_rh_t *)ng_ipv6_ext_get_next((ng_ipv6_ext_t *)ext);
+                break;
+
+            case NG_PROTNUM_IPV6_EXT_RH:
+                c = false;
+                break;
+
+            default:
+                c = false;
+                break;
+        }
+    }
+
+    if (ipv6->nh == NG_PROTNUM_IPV6_EXT_RH) {
+        switch (ext->type) {
+            default:
+                break;
+        }
+    }
+
+    return NULL;
+}
+
+/** @} */

sys/net/network_layer/ng_ndp/ng_ndp.c

@@ -20,6 +20,7 @@
 #include "byteorder.h"
 #include "net/ng_icmpv6.h"
 #include "net/ng_ipv6.h"
+#include "net/ng_ipv6/ext/rh.h"
 #include "net/ng_netbase.h"
 #include "random.h"
 #include "utlist.h"
@@ -337,8 +338,14 @@ kernel_pid_t ng_ndp_next_hop_l2addr(uint8_t *l2addr, uint8_t *l2addr_len,
     ng_ipv6_addr_t *next_hop_ip = NULL, *prefix = NULL;
 #ifdef MODULE_FIB
     size_t next_hop_size;
+#endif
 
-    if ((fib_get_next_hop(&iface, (uint8_t *)next_hop_ip, &next_hop_size,
+#ifdef MODULE_NG_IPV6_EXT_RH
+    next_hop_ip = ng_ipv6_ext_rh_next_hop(hdr);
+#endif
+#ifdef MODULE_FIB
+    if ((next_hop_ip == NULL) &&
+        (fib_get_next_hop(&iface, (uint8_t *)next_hop_ip, &next_hop_size,
                           (uint8_t *)dst, sizeof(ng_ipv6_addr_t),
                           0) < 0) || (next_hop_ip != sizeof(ng_ipv6_addr_t))) {
         next_hop_ip = NULL;