Hi, You can access UDP header like this: udp_header = (struct udphdr *)(skb->data + (skb->nh.iph->ihl *4)); Regards, Mahesh. -----Original Message----- From: linux-net-owner@xxxxxxxxxxxxxxx [mailto:linux-net-owner@xxxxxxxxxxxxxxx] On Behalf Of Shrikrishna Khare Sent: Wednesday, April 30, 2008 7:14 AM To: linux-net@xxxxxxxxxxxxxxx Subject: Extracting UDP header from skb while forwarding Hello All, My queuing discipline requires me to access destination port for UDP packets that I am sending. When I have machine A sending to machine B, a simple code like struct udphdr* udp_header = udp_hdr(skb) works fine. However, when I have A sending data to C through B (i.e. B as forwarding engine), I find that both, skb->transport_header and skb_network_header are equal when accessed from queuing discipline code. How can I access transport_header then? I tried extracting it from skb->data but the code keeps crashing. Could anyone please tell me how can I access transport header from queuing disciplines code then? I know machine B should not be looking at transport layer fields. But I need to do it for testing some functionality. Thanks in advance! Shrikrishna ________________________________________________________________________ ____________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ -- To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html SASKEN BUSINESS DISCLAIMER ------------------------- This message may contain confidential, proprietary or legally privileged information. In case you are not the original intended Recipient of the message, you must not, directly or indirectly, use, Disclose, distribute, print, or copy any part of this message and you are requested to delete it and inform the sender. Any views expressed in this message are those of the individual sender unless otherwise stated. Nothing contained in this message shall be construed as an offer or acceptance of any offer by Sasken Communication Technologies Limited ("Sasken") unless sent with that express intent and with due authority of Sasken. Sasken has taken enough precautions to prevent the spread of viruses. However the company accepts no liability for any damage caused by any virus transmitted by this email -- To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
