struct sr_instance* get_sr() {
struct sr_instance* sr;
sr = sr_get_global_instance( NULL );
assert( sr );
return sr;
}
/* Given a destination ip address:
* - find interface the packet would be shipped through
* - return this interface's ip address as the src ip address
*/
uint32_t find_srcip(uint32_t dest) {
struct sr_instance* sr = sr_get_global_instance(0);
router_state* rs = (router_state*)sr->interface_subsystem;
iface_entry* iface_struct;
char *iface = 0;
struct in_addr dst;
struct in_addr src;
uint32_t srcip;
iface = calloc(32, sizeof(char));
dst.s_addr = dest;
src.s_addr = 0;
lock_if_list_rd(rs);
lock_rtable_rd(rs);
if(get_next_hop(&src, iface, 32, rs, &dst)) {
srcip = 0;
}
else {
iface_struct = get_iface(rs, iface);
assert(iface_struct);
srcip = iface_struct->ip;
}
unlock_rtable(rs);
unlock_if_list(rs);
return srcip;
}
uint32_t integ_ip_output(uint8_t *payload, uint8_t proto, uint32_t src, uint32_t dest, int len) {
assert(payload);
struct sr_instance* sr = sr_get_global_instance(0);
int retval = send_ip_packet(sr, proto, src, dest, payload, len);
free(payload);
return retval;
}
static void sr_low_level_network_subsystem(void *arg)
{
struct sr_instance* sr = (struct sr_instance*)arg;
/* -- set argument as global singleton -- */
sr_get_global_instance(sr);
#ifdef _CPUMODE_
/* -- whizbang main loop ;-) */
while( sr_cpu_input(sr) == 1);
#else
/* -- whizbang main loop ;-) */
while( sr_vns_read_from_server(sr) == 1);
#endif
/* -- this is the end ... my only friend .. the end -- */
sr_destroy_instance(sr);
} /* -- sr_low_level_network_subsystem -- */