xref: /csrg-svn/sys/net/if_loop.c (revision 5161)
1*5161Swnj /*	if_loop.c	4.2	81/12/02	*/
25122Swnj 
35122Swnj /*
45122Swnj  * Loopback interface driver for protocol testing and timing.
55122Swnj  */
65122Swnj 
75122Swnj #include "../h/param.h"
85122Swnj #include "../h/systm.h"
95122Swnj #include "../h/mbuf.h"
105122Swnj #include "../h/socket.h"
115122Swnj #include "../net/in.h"
125122Swnj #include "../net/in_systm.h"
135122Swnj #include "../net/if.h"
145122Swnj #include "../net/ip.h"
155122Swnj #include "../net/ip_var.h"
165122Swnj #include "../h/mtpr.h"
175122Swnj 
185122Swnj #define	LONET	254
195122Swnj #define	LOMTU	1024
205122Swnj 
215122Swnj struct	ifnet loif;
225122Swnj int	looutput();
235122Swnj 
245122Swnj loattach()
255122Swnj {
265122Swnj 	register struct ifnet *ifp = &loif;
275122Swnj 
285122Swnj 	ifp->if_mtu = LOMTU;
295122Swnj 	ifp->if_net = LONET;
305122Swnj 	ifp->if_output = looutput;
315122Swnj 	ifp->if_next = ifnet;
32*5161Swnj 	if_attach(ifp);
335122Swnj }
345122Swnj 
355122Swnj looutput(ifp, m0, pf)
365122Swnj 	struct ifnet *ifp;
375122Swnj 	struct mbuf *m0;
385122Swnj 	int pf;
395122Swnj {
405122Swnj 	int s = splimp();
415122Swnj 
425122Swnj 	switch (pf) {
435122Swnj 
445122Swnj #ifdef INET
455122Swnj 	case PF_INET:
465122Swnj 		IF_ENQUEUE(&ipintrq, m0);
475122Swnj 		setipintr();
485122Swnj 		break;
495122Swnj #endif
505122Swnj 
515122Swnj 	default:
525122Swnj 		splx(s);
535122Swnj 		printf("lo%d: can't encapsulate pf%d\n", ifp->if_unit, pf);
545122Swnj 		m_freem(m0);
555122Swnj 		return (0);
565122Swnj 	}
575122Swnj 	splx(s);
585122Swnj 	return (1);
595122Swnj }
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