6lowpan: handle context based source address
Handle context based address when an unspecified address is given.
For other context based address we print a warning and drop the packet
because we don't support it right now.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Reviewed-by: Werner Almesberger <werner@almesberger.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 5ef9157..c85e71e 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -242,6 +242,40 @@
return 0;
}
+/* Uncompress address function for source context
+ * based address(non-multicast).
+ */
+static int
+lowpan_uncompress_context_based_src_addr(struct sk_buff *skb,
+ struct in6_addr *ipaddr,
+ const u8 sam)
+{
+ switch (sam) {
+ case LOWPAN_IPHC_ADDR_00:
+ /* unspec address ::
+ * Do nothing, address is already ::
+ */
+ break;
+ case LOWPAN_IPHC_ADDR_01:
+ /* TODO */
+ case LOWPAN_IPHC_ADDR_02:
+ /* TODO */
+ case LOWPAN_IPHC_ADDR_03:
+ /* TODO */
+ netdev_warn(skb->dev, "SAM value 0x%x not supported\n", sam);
+ return -EINVAL;
+ default:
+ pr_debug("Invalid sam value: 0x%x\n", sam);
+ return -EINVAL;
+ }
+
+ lowpan_raw_dump_inline(NULL,
+ "Reconstructed context based ipv6 src addr is:\n",
+ ipaddr->s6_addr, 16);
+
+ return 0;
+}
+
/* Uncompress function for multicast destination address,
* when M bit is set.
*/
@@ -970,9 +1004,18 @@
/* Extract SAM to the tmp variable */
tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03;
- /* Source address uncompression */
- pr_debug("source address stateless compression\n");
- err = lowpan_uncompress_addr(skb, &hdr.saddr, tmp, _saddr);
+ if (iphc1 & LOWPAN_IPHC_SAC) {
+ /* Source address context based uncompression */
+ pr_debug("SAC bit is set. Handle context based source address.\n");
+ err = lowpan_uncompress_context_based_src_addr(
+ skb, &hdr.saddr, tmp);
+ } else {
+ /* Source address uncompression */
+ pr_debug("source address stateless compression\n");
+ err = lowpan_uncompress_addr(skb, &hdr.saddr, tmp, _saddr);
+ }
+
+ /* Check on error of previous branch */
if (err)
goto drop;