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 616f2f6..59678da 100644 --- a/net/ieee802154/6lowpan.c +++ b/net/ieee802154/6lowpan.c @@ -448,9 +448,14 @@ lowpan_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("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 2869c05..2bc231f 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) -- 1.8.4.2 ------------------------------------------------------------------------------ DreamFactory - Open Source REST & JSON Services for HTML5 & Native Apps OAuth, Users, Roles, SQL, NoSQL, BLOB Storage and External API Access Free app hosting. Or install the open source package on any LAMP server. Sign up and see examples for AngularJS, jQuery, Sencha Touch and Native! http://pubads.g.doubleclick.net/gampad/clk?id=63469471&iu=/4140/ostg.clktrk _______________________________________________ Linux-zigbee-devel mailing list Linux-zigbee-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-zigbee-devel
