/* if_loop.c 4.1 81/11/29 */
/*
* Loopback interface driver for protocol testing and timing.
*/
#include "../h/param.h"
#include "../h/systm.h"
#include "../h/mbuf.h"
#include "../h/socket.h"
#include "../net/in.h"
#include "../net/in_systm.h"
#include "../net/if.h"
#include "../net/ip.h"
#include "../net/ip_var.h"
#include "../h/mtpr.h"
#define LONET 254
#define LOMTU 1024
struct ifnet loif;
int looutput();
loattach()
{
register struct ifnet *ifp = &loif;
ifp->if_mtu = LOMTU;
ifp->if_net = LONET;
ifp->if_output = looutput;
ifp->if_next = ifnet;
ifnet = ifp;
}
looutput(ifp, m0, pf)
struct ifnet *ifp;
struct mbuf *m0;
int pf;
{
int s = splimp();
switch (pf) {
#ifdef INET
case PF_INET:
IF_ENQUEUE(&ipintrq, m0);
setipintr();
break;
#endif
default:
splx(s);
printf("lo%d: can't encapsulate pf%d\n", ifp->if_unit, pf);
m_freem(m0);
return (0);
}
splx(s);
return (1);
}