/* $OpenBSD: mpls_input.c,v 1.13 2008/05/23 16:06:29 thib Exp $ */ /* * Copyright (c) 2008 Claudio Jeker * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include "mpe.h" #include #include #include #include #include #include #include #include struct ifqueue mplsintrq; int mplsqmaxlen = IFQ_MAXLEN; extern int mpls_inkloop; #ifdef MPLS_DEBUG #define MPLS_LABEL_GET(l) ((ntohl((l) & MPLS_LABEL_MASK)) >> MPLS_LABEL_OFFSET) #define MPLS_TTL_GET(l) (ntohl((l) & MPLS_TTL_MASK)) #endif void mpls_init(void) { mplsintrq.ifq_maxlen = mplsqmaxlen; } void mplsintr(void) { struct mbuf *m; int s; for (;;) { /* Get next datagram of input queue */ s = splnet(); IF_DEQUEUE(&mplsintrq, m); splx(s); if (m == NULL) return; #ifdef DIAGNOSTIC if ((m->m_flags & M_PKTHDR) == 0) panic("ipintr no HDR"); #endif mpls_input(m); } } 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; u_int32_t ttl; int i, hasbos; if (!mpls_enable) { 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 /* MPLS_DEBUG */ /* check and decrement TTL */ ttl = ntohl(shim->shim_label & MPLS_TTL_MASK); if (ttl <= 1) { /* TTL exceeded */ /* * XXX if possible hand packet up to network layer so that an * ICMP TTL exceeded can be sent back. */ m_freem(m); return; } ttl = htonl(ttl - 1); for (i = 0; i < mpls_inkloop; i++) { bzero(&sa_mpls, sizeof(sa_mpls)); smpls = &sa_mpls; smpls->smpls_family = AF_MPLS; smpls->smpls_len = sizeof(*smpls); smpls->smpls_in_ifindex = ifp->if_index; smpls->smpls_in_label = shim->shim_label & MPLS_LABEL_MASK; #ifdef MPLS_DEBUG printf("smpls af %d len %d in_label %d in_ifindex %d\n", smpls->smpls_family, smpls->smpls_len, MPLS_LABEL_GET(smpls->smpls_in_label), smpls->smpls_in_ifindex); #endif rt = rtalloc1(smplstosa(smpls),1, 0); if (rt == NULL) { /* no entry for this label */ #ifdef MPLS_DEBUG printf("MPLS_DEBUG: label not found\n"); #endif m_freem(m); goto done; } rt->rt_use++; smpls = satosmpls(rt_key(rt)); #ifdef MPLS_DEBUG printf("route af %d len %d in_label %d in_ifindex %d\n", smpls->smpls_family, smpls->smpls_len, MPLS_LABEL_GET(smpls->smpls_in_label), smpls->smpls_in_ifindex); printf("\top %d out_label %d out_ifindex %d\n", smpls->smpls_operation, MPLS_LABEL_GET(smpls->smpls_out_label), smpls->smpls_out_ifindex); #endif switch (smpls->smpls_operation) { case MPLS_OP_POP: hasbos = MPLS_BOS_ISSET(shim->shim_label); m = mpls_shim_pop(m); if (hasbos) { #if NMPE > 0 if (rt->rt_ifp->if_type == IFT_MPLS) { mpe_input(m, rt->rt_ifp, smpls, ttl); goto done; } #endif /* last label but we have no clue so drop */ m_freem(m); goto done; } break; case MPLS_OP_PUSH: m = mpls_shim_push(m, smpls); break; case MPLS_OP_SWAP: m = mpls_shim_swap(m, smpls); break; default: m_freem(m); goto done; } if (m == NULL) goto done; /* refetch label */ shim = mtod(m, struct shim_hdr *); ifp = rt->rt_ifp; if (smpls->smpls_out_ifindex) break; RTFREE(rt); rt = NULL; } /* write back TTL */ shim->shim_label = (shim->shim_label & ~MPLS_TTL_MASK) | ttl; #ifdef MPLS_DEBUG printf("MPLS: sending on %s outlabel %x dst af %d in %d out %d\n", ifp->if_xname, ntohl(shim->shim_label), smpls->smpls_family, MPLS_LABEL_GET(smpls->smpls_in_label), MPLS_LABEL_GET(smpls->smpls_out_label)); #endif (*ifp->if_output)(ifp, m, smplstosa(smpls), rt); done: if (rt) RTFREE(rt); }