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.h | 1 + net/ieee802154/6lowpan_iphc.c | 11 ++++++++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/net/ieee802154/6lowpan.h b/net/ieee802154/6lowpan.h index 10909e5..4942c5d 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 */ #ifdef DEBUG /* print data in line */ diff --git a/net/ieee802154/6lowpan_iphc.c b/net/ieee802154/6lowpan_iphc.c index a7ae340..8303c93 100644 --- a/net/ieee802154/6lowpan_iphc.c +++ b/net/ieee802154/6lowpan_iphc.c @@ -309,9 +309,14 @@ uncompress_udp_header(struct sk_buff *skb, struct udphdr *uh) 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_ratelimited("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 -- 1.8.5.1 ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Linux-zigbee-devel mailing list Linux-zigbee-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-zigbee-devel
