On Tue, Jul 10, 2012 at 11:42 AM, Adel Kodmani <[email protected]> wrote:
> I am writing a kernel module that actually modifies the TCP header(both at > sending and receiving) and I need to re-calculate the header because of > that. > I am capturing the packets using netfilter, so I have access to the whole > SKB, I am using Linux 2.6.35-22 > > Looking into the source code of the TCP/IP, I found this function > void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb); > The comment above it says this routing computes the IPv4 TCP checksum > > Trying to use this function, I called it passing to it skb->sk and skb > With no success so far. > > So my question is, how do I correctly calculate the TCP checksum? I know > there's a psudoheader that must be created, and added to the calculation > but there must be a function in the kernel I can call that already does > that. > > > Thanks in advance, > Adel > > _______________________________________________ > Kernelnewbies mailing list > [email protected] > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > > I think this may be helpful to you http://www.thegeekstuff.com/2012/05/ip-header-checksum/
_______________________________________________ Kernelnewbies mailing list [email protected] http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
