usr/src/sys/netns/ns_ip.c

/*      ns_ip.c     6.1     85/05/30     */

/*
 * Software interface driver for encapsulating ns in ip.
 */

#ifdef NSIP
#include "param.h"
#include "systm.h"
#include "mbuf.h"
#include "socket.h"
#include "errno.h"
#include "ioctl.h"

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

#include "../netinet/in.h"
#include "../netinet/in_systm.h"
#include "../netinet/in_var.h"
#include "../netinet/ip.h"
#include "../netinet/ip_var.h"

#ifdef vax
#include "../vax/mtpr.h"
#endif

#include "../netns/ns.h"
#include "../netns/ns_if.h"
#include "../netns/idp.h"

struct ifnet_en {
        struct ifnet ifen_ifnet;
        struct route ifen_route;
        struct in_addr ifen_src;
        struct in_addr ifen_dst;
};

int     nsipoutput(), nsipioctl();
#define LOMTU   (1024+512);

struct ifnet nsipif;
union ns_net nsip_net;
struct mbuf *nsip_list;         /* list of all hosts and gateways or
                                        broadcast addrs */

struct mbuf *
nsipattach()
{
        register struct mbuf *m = m_getclr(M_DONTWAIT, MT_PCB);
        register struct ifnet *ifp;
        register struct sockaddr_in *sin;

        if (m==0) return (0);
        m->m_off = MMINOFF;
        m->m_len = sizeof(struct ifnet_en);
        m->m_next = nsip_list;
        nsip_list = m;
        ifp = mtod(m, struct ifnet *);

        ifp->if_name = "nsip";
        ifp->if_mtu = LOMTU;
        ifp->if_ioctl = nsipioctl;
        ifp->if_output = nsipoutput;
        ifp->if_flags = IFF_POINTOPOINT;
        ifp->if_unit = nsipif.if_unit++;
        if_attach(ifp);
        return(dtom(ifp));
}


/*
 * Process an ioctl request.
 */
/* ARGSUSED */
nsipioctl(ifp, cmd, data)
        register struct ifnet *ifp;
        int cmd;
        caddr_t data;
{
        int error = 0;

        switch (cmd) {

        case SIOCSIFADDR:
                ifp->if_flags |= IFF_UP;
                /*
                 * Everything else is done at a higher level.
                 */
                break;

        default:
                error = EINVAL;
        }
        return (error);
}

struct mbuf *nsip_badlen;
struct mbuf *nsip_lastin;
int nsip_hold_input;

idpip_input(m0)
        struct mbuf *m0;
{
        register struct ip *ip;
        register struct idp *idp;
        register struct mbuf *m;
        register struct ifqueue *ifq = &nsintrq;
        int len, s;

        if(nsip_hold_input) {
                if(nsip_lastin) {
                        m_free(nsip_lastin);
                }
                nsip_lastin = m_copy(m0, 0, M_COPYALL);
        }
        /*
         * Get IP and IDP header together in first mbuf.
         */
        nsipif.if_ipackets++;
        m = m0;
        s = sizeof (struct ip) + sizeof (struct idp);
        if ((m->m_off > MMAXOFF || m->m_len < s) &&
            (m = m_pullup(m, s))==0) {
                nsipif.if_ierrors++;
                return;
        }
        ip = mtod(m, struct ip *);
        if (ip->ip_hl > (sizeof (struct ip) >> 2))
                ip_stripoptions(ip, (struct mbuf *)0);

        /*
         * Make mbuf data length reflect IDP length.
         * If not enough data to reflect IDP length, drop.
         */
        m->m_off += sizeof (struct ip);
        m->m_len -= sizeof (struct ip);
        idp = mtod(m, struct idp *);
        len = ntohs(idp->idp_len);
        if (ip->ip_len != len) {
                if (len > ip->ip_len) {
                        nsipif.if_ierrors++;
                        if(nsip_badlen) m_freem(nsip_badlen);
                        nsip_badlen = m;
                        return;
                }
                m_adj(m, len - ip->ip_len);
                /* ip->ip_len = len; */
        }
        /*
         * Deliver to NS
         */
        s = splimp();
        if (IF_QFULL(ifq)) {
                IF_DROP(ifq);
                m_freem(m0);
                splx(s);
                return (ENOBUFS);
        }
        IF_ENQUEUE(ifq, m0);
        schednetisr(NETISR_NS);
        splx(s);
        return (0);
bad:
        m_freem(m);
        return (0);
}

nsipoutput(ifn, m0, dst)
        struct ifnet_en *ifn;
        struct mbuf *m0;
        struct sockaddr *dst;
{

        register struct mbuf *m = dtom(ifn);
        register struct ip *ip;
        register struct route *ro = &(ifn->ifen_route);
        register int len = 0;
        struct in_addr in_src, in_dst;
        register struct idp *idp = mtod(m0, struct idp *);
        int error;

        if (m->m_len != sizeof(struct ifnet_en)) {
                printf("nsipoutput: bad dst ifp %x\n", ifn);
                goto bad;
        }
        ifn->ifen_ifnet.if_opackets++;
        nsipif.if_opackets++;


        /*
         * Calculate data length and make space
         * for IP header.
         */
        len =  ntohs(idp->idp_len);
        m = m0;
        if(m->m_off < MMINOFF + sizeof (struct ip)) {
                m = m_get(M_DONTWAIT, MT_HEADER);
                if (m == 0) {
                        m_freem(m0);
                        return (ENOBUFS);
                }
                m->m_off = MMAXOFF - sizeof (struct ip);
                m->m_len = sizeof (struct ip);
                m->m_next = m0;
        } else {
                m->m_off -= sizeof (struct ip);
                m->m_len += sizeof (struct ip);
        }
        /*
         * Fill in IP header.
         */
        ip = mtod(m, struct ip *);
        *(long *)ip = 0;
        ip->ip_p = IPPROTO_PUP;
        ip->ip_src = ifn->ifen_src;
        ip->ip_dst = ifn->ifen_dst;
        ip->ip_len = (u_short)len + sizeof (struct ip);
        ip->ip_ttl = MAXTTL;

        /*
         * Output final datagram.
         */
        error =  (ip_output(m, (struct mbuf *)0, ro, SO_BROADCAST));
        if (error) {
                ifn->ifen_ifnet.if_oerrors++;
                ifn->ifen_ifnet.if_ierrors = error;
        }
        return (error);
bad:
        m_freem(m0);
        return(ENETUNREACH);
}

struct ifreq ifr = {"nsip0"};

nsip_route(m)
        register struct mbuf *m;
{
        register struct nsip_req *rq = mtod(m, struct nsip_req *);
        struct sockaddr_ns *ns_dst = (struct sockaddr_ns *)&rq->rq_ns;
        struct sockaddr_in *ip_dst = (struct sockaddr_in *)&rq->rq_ip;
        int flags = rq->rq_flags;
        struct ifnet *ifp;
        struct route ro;
        struct ifnet_en *ifn;
        int error;
        struct sockaddr_in *dst;
        struct sockaddr_in *src;
        /*
         * First, determine if we can get to the destination
         */
        bzero((caddr_t)&ro, sizeof (ro));
        ro.ro_dst = *(struct sockaddr *)ip_dst;
        dst = (struct sockaddr_in *)& ro.ro_dst;
        rtalloc(&ro);
        if (ro.ro_rt == 0 || (ifp = ro.ro_rt->rt_ifp) == 0) {
                return (ENETUNREACH);
        }
        /*
         * And see how he's going to get back to us:
         */
        {
                register struct in_ifaddr *ia;
                struct ifnet *ifp = ro.ro_rt->rt_ifp;

                for (ia = in_ifaddr; ia; ia = ia->ia_next)
                        if (ia->ia_ifp == ifp)
                                break;
                if (ia == 0)
                        ia = in_ifaddr;
                if (ia == 0) {
                        return (EADDRNOTAVAIL);
                }
                src = (struct sockaddr_in *)&ia->ia_addr;
        }
        /*
         * Is there space?
         */
        m = nsipattach();
        if (m==NULL) {return (ENOBUFS);}
        ifn = mtod(m, struct ifnet_en *);

        ro.ro_rt->rt_use++;
        ifn->ifen_route = ro;
        ifn->ifen_dst =  ip_dst->sin_addr;
        ifn->ifen_src = src->sin_addr;

        /*
         * now configure this as a point to point link
         */
        ifr.ifr_name[4] = '0' + nsipif.if_unit - 1;
        ifr.ifr_dstaddr = * (struct sockaddr *) ns_dst;
        return(ns_control((struct socket *)0, SIOCSIFADDR, (caddr_t)&ifr,
                        (struct ifnet *)ifn));
}
#endif