On Thu, 20 Jan 2005 15:52:34 -0500 (EST) Rahul Jain <[EMAIL PROTECTED]> wrote:
> Hi, > > I have written a module that changes IP addrs and TCP port values. After > changing these fields, I am able to recalculate the IP checksum within > the module. To recalculate the TCP checksum, I wrote a new function in > tcp_ipv4.c which is very similar to tcp_v4_send_check(). The only > difference is that, my function does not use the sock parameter and gets > the saddr and daddr from sk_buff. I call this function before the > following piece of code in tcp_v4_rcv() > > if ((skb->ip_summed != CHECKSUM_UNNECESSARY && > tcp_v4_checksum_init(skb) < 0)) > goto bad_packet; > > However I am still getting a bad tcp checksum error. Does anyone know what > I am missing and point me in the right direction. > Look at the netfilter code, in fact if you are changing values there may already be a netfilter module to do what you want, and you could have saved the effort. -- Stephen Hemminger <[EMAIL PROTECTED]> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/