usr/src/sys/netns/ns_output.c

/*
 * Copyright (c) 1984, 1985, 1986, 1987 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 *      @(#)ns_output.c 7.6 (Berkeley) %G%
 */

#include "param.h"
#include "malloc.h"
#include "mbuf.h"
#include "errno.h"
#include "socket.h"
#include "socketvar.h"

#include "../net/if.h"
#include "../net/route.h"

#include "ns.h"
#include "ns_if.h"
#include "idp.h"
#include "idp_var.h"

#ifdef vax
#include "../vax/mtpr.h"
#endif
int ns_hold_output = 0;
int ns_copy_output = 0;
int ns_output_cnt = 0;
struct mbuf *ns_lastout;

ns_output(m0, ro, flags)
        struct mbuf *m0;
        struct route *ro;
        int flags;
{
        register struct idp *idp = mtod(m0, struct idp *);
        register struct ifnet *ifp = 0;
        int error = 0;
        struct route idproute;
        struct sockaddr_ns *dst;
        extern int idpcksum;

        if (ns_hold_output) {
                if (ns_lastout) {
                        (void)m_free(ns_lastout);
                }
                ns_lastout = m_copy(m0, 0, (int)M_COPYALL);
        }
        /*
         * Route packet.
         */
        if (ro == 0) {
                ro = &idproute;
                bzero((caddr_t)ro, sizeof (*ro));
        }
        dst = (struct sockaddr_ns *)&ro->ro_dst;
        if (ro->ro_rt == 0) {
                dst->sns_family = AF_NS;
                dst->sns_len = sizeof (*dst);
                dst->sns_addr = idp->idp_dna;
                dst->sns_addr.x_port = 0;
                /*
                 * If routing to interface only,
                 * short circuit routing lookup.
                 */
                if (flags & NS_ROUTETOIF) {
                        struct ns_ifaddr *ia = ns_iaonnetof(&idp->idp_dna);

                        if (ia == 0) {
                                error = ENETUNREACH;
                                goto bad;
                        }
                        ifp = ia->ia_ifp;
                        goto gotif;
                }
                rtalloc(ro);
        } else if ((ro->ro_rt->rt_flags & RTF_UP) == 0) {
                /*
                 * The old route has gone away; try for a new one.
                 */
                rtfree(ro->ro_rt);
                ro->ro_rt = NULL;
                rtalloc(ro);
        }
        if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0) {
                error = ENETUNREACH;
                goto bad;
        }
        ro->ro_rt->rt_use++;
        if (ro->ro_rt->rt_flags & (RTF_GATEWAY|RTF_HOST))
                dst = (struct sockaddr_ns *)ro->ro_rt->rt_gateway;
gotif:

        /*
         * Look for multicast addresses and
         * and verify user is allowed to send
         * such a packet.
         */
        if (dst->sns_addr.x_host.c_host[0]&1) {
                if ((ifp->if_flags & IFF_BROADCAST) == 0) {
                        error = EADDRNOTAVAIL;
                        goto bad;
                }
                if ((flags & NS_ALLOWBROADCAST) == 0) {
                        error = EACCES;
                        goto bad;
                }
        }

        if (htons(idp->idp_len) <= ifp->if_mtu) {
                ns_output_cnt++;
                if (ns_copy_output) {
                        ns_watch_output(m0, ifp);
                }
                error = (*ifp->if_output)(ifp, m0,
                                        (struct sockaddr *)dst, ro->ro_rt);
                goto done;
        } else error = EMSGSIZE;


bad:
        if (ns_copy_output) {
                ns_watch_output(m0, ifp);
        }
        m_freem(m0);
done:
        if (ro == &idproute && (flags & NS_ROUTETOIF) == 0 && ro->ro_rt) {
                RTFREE(ro->ro_rt);
                ro->ro_rt = 0;
        }
        return (error);
}