From 8f763535ac4de93e1ff980d25ec954dadbf1af5d Mon Sep 17 00:00:00 2001
From: Martine Lenders <mail@martine-lenders.eu>
Date: Thu, 29 Nov 2018 23:41:14 +0100
Subject: [PATCH] gnrc_netif: centralize S/TLLAO length to address length
function
The function to infer the link-layer address length from the length of
a S/TLLAO is very dependent on the IPv6 over X specification and thus
should be grouped with the other IP over X functions.
---
sys/include/net/gnrc/netif/internal.h | 35 ++++++++++-
sys/net/gnrc/netif/gnrc_netif_device_type.c | 50 +++++++++++++++
.../gnrc/network_layer/ipv6/nib/_nib-arsm.c | 61 ++-----------------
3 files changed, 89 insertions(+), 57 deletions(-)
diff --git a/sys/include/net/gnrc/netif/internal.h b/sys/include/net/gnrc/netif/internal.h
index 3e71290602..bcf3aaa36b 100644
--- a/sys/include/net/gnrc/netif/internal.h
+++ b/sys/include/net/gnrc/netif/internal.h
@@ -495,9 +495,40 @@ static inline int gnrc_netif_ipv6_get_iid(gnrc_netif_t *netif, eui64_t *iid)
(void)iid;
return -ENOTSUP;
}
+
+/**
+ * @brief Derives the length of the link-layer address in an NDP link-layer
+ * address option from that option's length field and the given device
+ * type.
+ *
+ * @note If an RFC exists that specifies how IPv6 operates over a link-layer,
+ * this function usually implements the section "Unicast Address
+ * Mapping".
+ *
+ * @see [RFC 4861, section 4.6.1](https://tools.ietf.org/html/rfc4861#section-4.6.1)
+ *
+ * @pre `netif->flags & GNRC_NETIF_FLAGS_HAS_L2ADDR`
+ *
+ * @attention When `NDEBUG` is not defined, the node fails with an assertion
+ * instead of returning `-ENOTSUP`
+ *
+ * @param[in] netif The network interface @p opt was received on within an NDP
+ * message.
+ * @param[in] opt An NDP source/target link-layer address option.
+ *
+ * @return Length of the link-layer address in @p opt on success
+ * @return `-ENOTSUP`, when implementation does not know how to derive the
+ * length of the link-layer address from @p opt's length field based
+ * on gnrc_netif_t::device_type of @p netif.
+ * @return `-EINVAL` if `opt->len` was an invalid value for the given
+ * gnrc_netif_t::device_type of @p netif.
+ */
+int gnrc_netif_ndp_addr_len_from_l2ao(gnrc_netif_t *netif,
+ const ndp_opt_t *opt);
#else /* defined(MODULE_GNRC_IPV6) || defined(DOXYGEN) */
-#define gnrc_netif_ipv6_iid_from_addr(netif, addr, addr_len, iid) (-ENOTSUP)
-#define gnrc_netif_ipv6_iid_to_addr(netif, iid, addr) (-ENOTSUP)
+#define gnrc_netif_ipv6_iid_from_addr(netif, addr, addr_len, iid) (-ENOTSUP)
+#define gnrc_netif_ipv6_iid_to_addr(netif, iid, addr) (-ENOTSUP)
+#define gnrc_netif_ndp_addr_len_from_l2ao(netif, opt) (-ENOTSUP)
#define gnrc_netif_ipv6_get_iid(netif, iid) (-ENOTSUP)
#endif /* defined(MODULE_GNRC_IPV6) || defined(DOXYGEN) */
/** @} */
diff --git a/sys/net/gnrc/netif/gnrc_netif_device_type.c b/sys/net/gnrc/netif/gnrc_netif_device_type.c
index a44fdc3a3b..87a42a8754 100644
--- a/sys/net/gnrc/netif/gnrc_netif_device_type.c
+++ b/sys/net/gnrc/netif/gnrc_netif_device_type.c
@@ -148,6 +148,56 @@ int gnrc_netif_ipv6_iid_to_addr(const gnrc_netif_t *netif, const eui64_t *iid,
}
return -ENOTSUP;
}
+
+int gnrc_netif_ndp_addr_len_from_l2ao(gnrc_netif_t *netif,
+ const ndp_opt_t *opt)
+{
+ assert(netif->flags & GNRC_NETIF_FLAGS_HAS_L2ADDR);
+ switch (netif->device_type) {
+#ifdef MODULE_CC110X
+ case NETDEV_TYPE_CC110X:
+ (void)opt;
+ return sizeof(uint8_t);
+#endif /* MODULE_CC110X */
+#if defined(MODULE_NETDEV_ETH) || defined(MODULE_ESP_NOW)
+ case NETDEV_TYPE_ETHERNET:
+ case NETDEV_TYPE_ESP_NOW:
+ /* see https://tools.ietf.org/html/rfc2464#section-6*/
+ if (opt->len == 1U) {
+ return ETHERNET_ADDR_LEN;
+ }
+ else {
+ return -EINVAL;
+ }
+#endif /* defined(MODULE_NETDEV_ETH) || defined(MODULE_ESP_NOW) */
+#ifdef MODULE_NRFMIN
+ case NETDEV_TYPE_NRFMIN:
+ (void)opt;
+ return sizeof(uint16_t);
+#endif /* MODULE_NRFMIN */
+#if defined(MODULE_NETDEV_IEEE802154) || defined(MODULE_XBEE)
+ case NETDEV_TYPE_IEEE802154:
+ /* see https://tools.ietf.org/html/rfc4944#section-8 */
+ switch (opt->len) {
+ case 1U:
+ return IEEE802154_SHORT_ADDRESS_LEN;
+ case 2U:
+ return IEEE802154_LONG_ADDRESS_LEN;
+ default:
+ return -EINVAL;
+ }
+#endif /* defined(MODULE_NETDEV_IEEE802154) || defined(MODULE_XBEE) */
+ default:
+ (void)opt;
+#ifdef DEVELHELP
+ LOG_ERROR("gnrc_netif: can't get address length from NDP link-layer "
+ "address option on interface %u\n", netif->pid);
+#endif
+ assert(false);
+ break;
+ }
+ return -ENOTSUP;
+}
#endif /* MODULE_GNRC_IPV6 */
/** @} */
diff --git a/sys/net/gnrc/network_layer/ipv6/nib/_nib-arsm.c b/sys/net/gnrc/network_layer/ipv6/nib/_nib-arsm.c
index c2d37650a4..ca0e2f0ff5 100644
--- a/sys/net/gnrc/network_layer/ipv6/nib/_nib-arsm.c
+++ b/sys/net/gnrc/network_layer/ipv6/nib/_nib-arsm.c
@@ -30,18 +30,6 @@
static char addr_str[IPV6_ADDR_MAX_STR_LEN];
-/**
- * @brief Determines supposed link-layer address from interface and option
- * length
- *
- * @param[in] netif A network interface.
- * @param[in] opt A SL2AO or TL2AO.
- *
- * @return The length of the L2 address carried in @p opt.
- */
-static inline unsigned _get_l2addr_len(gnrc_netif_t *netif,
- const ndp_opt_t *opt);
-
void _snd_ns(const ipv6_addr_t *tgt, gnrc_netif_t *netif,
const ipv6_addr_t *src, const ipv6_addr_t *dst)
{
@@ -104,10 +92,10 @@ void _handle_sl2ao(gnrc_netif_t *netif, const ipv6_hdr_t *ipv6,
{
assert(netif != NULL);
_nib_onl_entry_t *nce = _nib_onl_get(&ipv6->src, netif->pid);
- unsigned l2addr_len;
+ int l2addr_len;
- l2addr_len = _get_l2addr_len(netif, sl2ao);
- if (l2addr_len == 0U) {
+ l2addr_len = gnrc_netif_ndp_addr_len_from_l2ao(netif, sl2ao);
+ if (l2addr_len < 0) {
DEBUG("nib: Unexpected SL2AO length. Ignoring SL2AO\n");
return;
}
@@ -174,43 +162,6 @@ void _handle_sl2ao(gnrc_netif_t *netif, const ipv6_hdr_t *ipv6,
}
}
-static inline unsigned _get_l2addr_len(gnrc_netif_t *netif,
- const ndp_opt_t *opt)
-{
- switch (netif->device_type) {
-#ifdef MODULE_CC110X
- case NETDEV_TYPE_CC110X:
- (void)opt;
- return sizeof(uint8_t);
-#endif /* MODULE_CC110X */
-#if defined(MODULE_NETDEV_ETH) || defined(MODULE_ESP_NOW)
- case NETDEV_TYPE_ETHERNET:
- case NETDEV_TYPE_ESP_NOW:
- (void)opt;
- return ETHERNET_ADDR_LEN;
-#endif /* defined(MODULE_NETDEV_ETH) || defined(MODULE_ESP_NOW) */
-#ifdef MODULE_NRFMIN
- case NETDEV_TYPE_NRFMIN:
- (void)opt;
- return sizeof(uint16_t);
-#endif /* MODULE_NRFMIN */
-#if defined(MODULE_NETDEV_IEEE802154) || defined(MODULE_XBEE)
- case NETDEV_TYPE_IEEE802154:
- switch (opt->len) {
- case 1U:
- return IEEE802154_SHORT_ADDRESS_LEN;
- case 2U:
- return IEEE802154_LONG_ADDRESS_LEN;
- default:
- return 0U;
- }
-#endif /* defined(MODULE_NETDEV_IEEE802154) || defined(MODULE_XBEE) */
- default:
- (void)opt;
- return 0U;
- }
-}
-
#if GNRC_IPV6_NIB_CONF_ARSM
/**
* @brief Calculates exponential back-off for retransmission timer for
@@ -379,13 +330,13 @@ void _probe_nbr(_nib_onl_entry_t *nbr, bool reset)
void _handle_adv_l2(gnrc_netif_t *netif, _nib_onl_entry_t *nce,
const icmpv6_hdr_t *icmpv6, const ndp_opt_t *tl2ao)
{
- unsigned l2addr_len = 0;
+ int l2addr_len = 0;
assert(nce != NULL);
assert(netif != NULL);
if (tl2ao != NULL) {
- l2addr_len = _get_l2addr_len(netif, tl2ao);
- if (l2addr_len == 0U) {
+ l2addr_len = gnrc_netif_ndp_addr_len_from_l2ao(netif, tl2ao);
+ if (l2addr_len < 0) {
DEBUG("nib: Unexpected TL2AO length. Ignoring TL2AO\n");
return;
}
--
GitLab