Bit 5 of "UDP LOWPAN_NHC Format" indicate that the checksum can be elided. The host need to calculate the udp checksum afterwards but this isn't supported right now.
See: http://tools.ietf.org/html/rfc6282#section-4.3.3 Signed-off-by: Alexander Aring <alex.ar...@gmail.com> --- net/ieee802154/6lowpan.c | 11 ++++++++--- net/ieee802154/6lowpan.h | 1 + 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c index 4477659..25c6864 100644 --- a/net/ieee802154/6lowpan.c +++ b/net/ieee802154/6lowpan.c @@ -456,9 +456,14 @@ lowpan_uncompress_udp_header(struct sk_buff *skb, pr_debug("uncompressed UDP ports: src = %d, dst = %d\n", ntohs(uh->source), ntohs(uh->dest)); - /* copy checksum */ - memcpy(&uh->check, &skb->data[0], 2); - skb_pull(skb, 2); + /* checksum */ + if (tmp & LOWPAN_NHC_UDP_CS_C) { + pr_debug("checksum elided currently not supported"); + goto err; + } else { + memcpy(&uh->check, &skb->data[0], 2); + skb_pull(skb, 2); + } /* * UDP lenght needs to be infered from the lower layers diff --git a/net/ieee802154/6lowpan.h b/net/ieee802154/6lowpan.h index 05a2a37..0109b5d 100644 --- a/net/ieee802154/6lowpan.h +++ b/net/ieee802154/6lowpan.h @@ -231,6 +231,7 @@ #define LOWPAN_NHC_UDP_CS_P_10 0xF2 /* source = 0xF0 + 8bit inline, dest = 16 bit inline */ #define LOWPAN_NHC_UDP_CS_P_11 0xF3 /* source & dest = 0xF0B + 4bit inline */ +#define LOWPAN_NHC_UDP_CS_C 0x04 /* checksum elided */ static inline bool lowpan_fetch_skb(struct sk_buff *skb, void *data, const unsigned int len) -- 1.8.4 ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60134071&iu=/4140/ostg.clktrk _______________________________________________ Linux-zigbee-devel mailing list Linux-zigbee-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-zigbee-devel
