void
mpls_input(struct mbuf *m)
{
struct ifnet *ifp = m->m_pkthdr.rcvif;
struct sockaddr_mpls *smpls;
struct sockaddr_mpls sa_mpls;
struct shim_hdr *shim;
struct rtentry *rt = NULL;
struct rt_mpls *rt_mpls;
u_int8_t ttl;
int i, s, hasbos;
if (!ISSET(ifp->if_xflags, IFXF_MPLS)) {
m_freem(m);
return;
}
/* drop all broadcast and multicast packets */
if (m->m_flags & (M_BCAST | M_MCAST)) {
m_freem(m);
return;
}
if (m->m_len < sizeof(*shim))
if ((m = m_pullup(m, sizeof(*shim))) == NULL)
return;
shim = mtod(m, struct shim_hdr *);
#ifdef MPLS_DEBUG
printf("mpls_input: iface %s label=%d, ttl=%d BoS %d\n",
ifp->if_xname, MPLS_LABEL_GET(shim->shim_label),
MPLS_TTL_GET(shim->shim_label),
MPLS_BOS_ISSET(shim->shim_label));
#endif
/* check and decrement TTL */
ttl = ntohl(shim->shim_label & MPLS_TTL_MASK);
if (ttl-- <= 1) {
/* TTL exceeded */
m = mpls_do_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, 0);
if (m == NULL)
return;
shim = mtod(m, struct shim_hdr *);
ttl = ntohl(shim->shim_label & MPLS_TTL_MASK);
}
/*
* Original (hw independent) Link layer output routine is wrapped by
* mpls_output, if focussed Link layer interface remains in MPLS enabled
* state. Original output routine is hooked by mpls_ifinfo{} and called
* by mpls_output.
*
* Any by protocol layer above transmitted mbuf(9) containing Protocol
* Data Uniit (pdu) must pass MPLS layer, if for transmission used interface
* on link-layer remains in MPLS enabled state.
*
* I/O Path, IPv4:
*
* rip_input() +{ socket layer }+ rip_output()
* / \
* / \
* +-->+ ip_input() +-->+ ip_forward() +-->+ ip_output()
* / \ \
* / \ +
* + +<------+ |
* | \ v
* + mpls_input() +--->+ mpls_forward() +------>+ mpls_output()
* |\ /|
* | \ +<-------+ |
* | \ / |
* | +<-----------+ if_simloop() +<-----------+ if_output()
* | |
* + if_input() |
* A |
* | V
*
*/
int
mpls_output(struct ifnet *ifp, struct mbuf *m,
const struct sockaddr *dst, struct route *ro)
{
struct mpls_ifinfo *mii;
struct mpls_ro mplsroute;
struct mpls_ro *mro;
struct sockaddr *gw;
int error = 0;
#ifdef MPLS_DEBUG
struct shim_hdr *shim;
#endif /* MPLS_DEBUG */
if ((ifp->if_flags & IFF_MPLS) == 0) {
/*
* Any pdu originates MPLS-layer are looped back into its
* domain, if for transmission used interface cannot accept
* by MPLS-layer processed pdu.
*
* See net/if_ethersubr.c and net/if_loop.c for further details.
*/
if (dst->sa_family == AF_MPLS)
if_simloop(ifp, m, dst->sa_family, 0);
else
error = (*ifp->if_output)(ifp, m, dst, ro);
goto out;
}
IF_AFDATA_RLOCK(ifp);
mii = MPLS_IFINFO(ifp);
IF_AFDATA_RUNLOCK(ifp);
mro = &mplsroute;
bzero(mro, sizeof(*mro));
if (ro == NULL)
ro = (struct route *)mro;
if (ro->ro_rt != NULL) {
/*
* If route exists, three cases are considered:
*
* (a) held route denotes fastpath.
* (b) held route denotes ilm,
*
* or
*
* (c) held route originates not AF_MPLS domain.
*/
if (ro->ro_rt->rt_flags & RTF_MPE) {
gw = ro->ro_rt->rt_gateway;
if ((m = mpls_encap(m, gw, mro)) == NULL) {
error = ECONNABORTED;
goto done;
}
gw = (struct sockaddr *)&mro->mro_gw;
} else
gw = (struct sockaddr *)dst;
} else
gw = (struct sockaddr *)dst;
if (m->m_flags & M_MPLS) {
/*
* Bypass tagging, if mbuf(9) was cached by MPLS_ARP.
*/
m->m_flags &= ~M_MPLS;
} else if (mii->mii_nhlfe != NULL) {
/*
* Otherwise, mbuf(9) must pass mpls_encap, if
* interface is bound by MPLS label binding on
* per-interface MPLS label space.
*/
mro->mro_ifa = mii->mii_nhlfe;
gw = mro->mro_ifa->ifa_dstaddr;
/*
* Per interface MPLS label space.
*/
if ((m = mpls_encap(m, gw, mro)) == NULL) {
error = ECONNABORTED;
goto done;
}
gw = (struct sockaddr *)&mro->mro_gw;
}
if (gw->sa_family == AF_MPLS) {
/*
* Defines iap for pfil(9) processing.
*/
if (PFIL_HOOKED(&V_inet_pfil_hook)
#ifdef INET6
|| PFIL_HOOKED(&V_inet6_pfil_hook)
#endif
) {
if (mpls_pfil(&m, ifp, PFIL_OUT) != 0)
goto done;
if (m == NULL)
goto done;
}
#ifdef MPLS_DEBUG
shim = mtod(m, struct shim_hdr *);
(void)printf("%s: on %s label %d ttl %d bos %d\n",
__func__, ifp->if_xname,
MPLS_LABEL_GET(shim->shim_label),
MPLS_TTL_GET(shim->shim_label),
MPLS_BOS(shim->shim_label));
#endif /* MPLS_DEBUG */
m->m_flags &= ~(M_BCAST|M_MCAST);
}
error = (*mii->mii_output)(ifp, m, gw, ro);
done:
if (mro != NULL)
mpls_rtfree(mro);
out:
return (error);
}
