Hi all,
I am sending some data over GRE tunnel for which I am setting IP_HDRINCL and populating inner ip header(final destination), so that socket will only build outer IP header(GRE tunnel destination).
After this I am unsetting the the router alert option. and sending the packet using send to function. It is failing to send data. can some one please look into it.

setsockopt(_ip_socket, IPPROTO_IP, IP_OPTIONS,
rsvp_alert, sizeof(rsvp_alert))

sendto(_ip_socket, final_data, iph->ip_len, MSG_DONTROUTE,
(struct sockaddr *)&saddr, sizeof(saddr))

Thanks,
Sudhir.