/* $OpenBSD: ip_mroute.c,v 1.93 2016/11/29 15:52:12 mpi Exp $ */ /* $NetBSD: ip_mroute.c,v 1.85 2004/04/26 01:31:57 matt Exp $ */ /* * Copyright (c) 1989 Stephen Deering * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Stephen Deering of Stanford University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)ip_mroute.c 8.2 (Berkeley) 11/15/93 */ /* * IP multicast forwarding procedures * * Written by David Waitzman, BBN Labs, August 1988. * Modified by Steve Deering, Stanford, February 1989. * Modified by Mark J. Steiglitz, Stanford, May, 1991 * Modified by Van Jacobson, LBL, January 1993 * Modified by Ajit Thyagarajan, PARC, August 1993 * Modified by Bill Fenner, PARC, April 1994 * Modified by Charles M. Hannum, NetBSD, May 1995. * Modified by Ahmed Helmy, SGI, June 1996 * Modified by George Edmond Eddy (Rusty), ISI, February 1998 * Modified by Pavlin Radoslavov, USC/ISI, May 1998, August 1999, October 2000 * Modified by Hitoshi Asaeda, WIDE, August 2000 * Modified by Pavlin Radoslavov, ICSI, October 2002 * * MROUTING Revision: 1.2 * and PIM-SMv2 and PIM-DM support, advanced API support, * bandwidth metering and signaling */ #ifdef PIM #define _PIM_VT 1 #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef PIM #include #include #endif #define M_PULLUP(m, len) \ do { \ if ((m) && ((m)->m_flags & M_EXT || (m)->m_len < (len))) \ (m) = m_pullup((m), (len)); \ } while (/*CONSTCOND*/ 0) /* * Globals. All but ip_mrouter and ip_mrtproto could be static, * except for netstat or debugging purposes. */ struct socket *ip_mrouter = NULL; int ip_mrtproto = IGMP_DVMRP; /* for netstat only */ #define NO_RTE_FOUND 0x1 #define RTE_FOUND 0x2 u_int32_t _mfchash(struct in_addr, struct in_addr); #define MFCHASH(a, g) _mfchash((a), (g)) LIST_HEAD(mfchashhdr, mfc) *mfchashtbl; u_long mfchash; SIPHASH_KEY mfchashkey; u_char nexpire[MFCTBLSIZ]; struct vif viftable[MAXVIFS]; struct mrtstat mrtstat; #define VIFI_INVALID ((vifi_t) -1) #define EXPIRE_TIMEOUT 250 /* 4x / second */ #define UPCALL_EXPIRE 6 /* number of timeouts */ struct timeout expire_upcalls_ch; int get_sg_cnt(struct sioc_sg_req *); int get_vif_cnt(struct sioc_vif_req *); int get_vif_ctl(struct vifctl *); int ip_mrouter_init(struct socket *, struct mbuf *); int get_version(struct mbuf *); int add_vif(struct mbuf *); int del_vif(struct mbuf *); void update_mfc_params(struct mfc *, struct mfcctl2 *); void init_mfc_params(struct mfc *, struct mfcctl2 *); void expire_mfc(struct mfc *); int add_mfc(struct mbuf *); int del_mfc(struct mbuf *); int set_api_config(struct mbuf *); /* chose API capabilities */ int get_api_support(struct mbuf *); int get_api_config(struct mbuf *); int socket_send(struct socket *, struct mbuf *, struct sockaddr_in *); void expire_upcalls(void *); int ip_mdq(struct mbuf *, struct ifnet *, struct mfc *); void phyint_send(struct ip *, struct vif *, struct mbuf *); void send_packet(struct vif *, struct mbuf *); #ifdef PIM int pim_register_send(struct ip *, struct vif *, struct mbuf *, struct mfc *); int pim_register_send_rp(struct ip *, struct vif *, struct mbuf *, struct mfc *); int pim_register_send_upcall(struct ip *, struct vif *, struct mbuf *, struct mfc *); struct mbuf *pim_register_prepare(struct ip *, struct mbuf *); int set_assert(struct mbuf *); int get_assert(struct mbuf *); struct pimstat pimstat; /* * Note: the PIM Register encapsulation adds the following in front of a * data packet: * * struct pim_encap_hdr { * struct ip ip; * struct pim_encap_pimhdr pim; * } * */ struct pim_encap_pimhdr { struct pim pim; uint32_t flags; }; #define PIM_ENCAP_TTL 64 static struct ip pim_encap_iphdr = { #if BYTE_ORDER == LITTLE_ENDIAN sizeof(struct ip) >> 2, IPVERSION, #else IPVERSION, sizeof(struct ip) >> 2, #endif 0, /* tos */ sizeof(struct ip), /* total length */ 0, /* id */ 0, /* frag offset */ PIM_ENCAP_TTL, IPPROTO_PIM, 0, /* checksum */ }; static struct pim_encap_pimhdr pim_encap_pimhdr = { { PIM_MAKE_VT(PIM_VERSION, PIM_REGISTER), /* PIM vers and message type */ 0, /* reserved */ 0, /* checksum */ }, 0 /* flags */ }; static struct ifnet multicast_register_if; static vifi_t reg_vif_num = VIFI_INVALID; /* * whether or not special PIM assert processing is enabled. */ static int pim_assert; #endif /* PIM */ static vifi_t numvifs = 0; /* * Rate limit for assert notification messages, in usec */ #define ASSERT_MSG_TIME 3000000 /* * Kernel multicast routing API capabilities and setup. * If more API capabilities are added to the kernel, they should be * recorded in `mrt_api_support'. */ static const u_int32_t mrt_api_support = (MRT_MFC_FLAGS_DISABLE_WRONGVIF | MRT_MFC_FLAGS_BORDER_VIF | MRT_MFC_RP); static u_int32_t mrt_api_config = 0; /* * Find a route for a given origin IP address and Multicast group address * Type of service parameter to be added in the future!!! * Statistics are updated by the caller if needed * (mrtstat.mrts_mfc_lookups and mrtstat.mrts_mfc_misses) */ static struct mfc * mfc_find(struct in_addr *o, struct in_addr *g) { struct mfc *rt; u_int32_t hash; hash = MFCHASH(*o, *g); LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) { if (in_hosteq(rt->mfc_origin, *o) && in_hosteq(rt->mfc_mcastgrp, *g) && (rt->mfc_stall == NULL)) break; } return (rt); } /* * Macros to compute elapsed time efficiently * Borrowed from Van Jacobson's scheduling code */ #define TV_DELTA(a, b, delta) do { \ int xxs; \ delta = (a).tv_usec - (b).tv_usec; \ xxs = (a).tv_sec - (b).tv_sec; \ switch (xxs) { \ case 2: \ delta += 1000000; \ /* FALLTHROUGH */ \ case 1: \ delta += 1000000; \ /* FALLTHROUGH */ \ case 0: \ break; \ default: \ delta += (1000000 * xxs); \ break; \ } \ } while (/*CONSTCOND*/ 0) /* * Handle MRT setsockopt commands to modify the multicast routing tables. */ int ip_mrouter_set(struct socket *so, int optname, struct mbuf **mp) { int error; if (optname != MRT_INIT && so != ip_mrouter) error = ENOPROTOOPT; else switch (optname) { case MRT_INIT: error = ip_mrouter_init(so, *mp); break; case MRT_DONE: error = ip_mrouter_done(); break; case MRT_ADD_VIF: error = add_vif(*mp); break; case MRT_DEL_VIF: error = del_vif(*mp); break; case MRT_ADD_MFC: error = add_mfc(*mp); break; case MRT_DEL_MFC: error = del_mfc(*mp); break; #ifdef PIM case MRT_ASSERT: error = set_assert(*mp); break; #endif case MRT_API_CONFIG: error = set_api_config(*mp); break; default: error = ENOPROTOOPT; break; } m_free(*mp); return (error); } /* * Handle MRT getsockopt commands */ int ip_mrouter_get(struct socket *so, int optname, struct mbuf **mp) { int error; if (so != ip_mrouter) error = ENOPROTOOPT; else { *mp = m_get(M_WAIT, MT_SOOPTS); switch (optname) { case MRT_VERSION: error = get_version(*mp); break; #ifdef PIM case MRT_ASSERT: error = get_assert(*mp); break; #endif case MRT_API_SUPPORT: error = get_api_support(*mp); break; case MRT_API_CONFIG: error = get_api_config(*mp); break; default: error = ENOPROTOOPT; break; } if (error) m_free(*mp); } return (error); } /* * Handle ioctl commands to obtain information from the cache */ int mrt_ioctl(struct socket *so, u_long cmd, caddr_t data) { int error; if (so != ip_mrouter) error = EINVAL; else switch (cmd) { case SIOCGETVIFCNT: error = get_vif_cnt((struct sioc_vif_req *)data); break; case SIOCGETSGCNT: error = get_sg_cnt((struct sioc_sg_req *)data); break; default: error = ENOTTY; break; } return (error); } /* * returns the packet, byte, rpf-failure count for the source group provided */ int get_sg_cnt(struct sioc_sg_req *req) { int s; struct mfc *rt; s = splsoftnet(); rt = mfc_find(&req->src, &req->grp); if (rt == NULL) { splx(s); req->pktcnt = req->bytecnt = req->wrong_if = 0xffffffff; return (EADDRNOTAVAIL); } req->pktcnt = rt->mfc_pkt_cnt; req->bytecnt = rt->mfc_byte_cnt; req->wrong_if = rt->mfc_wrong_if; splx(s); return (0); } /* * returns the input and output packet and byte counts on the vif provided */ int get_vif_cnt(struct sioc_vif_req *req) { vifi_t vifi = req->vifi; if (vifi >= numvifs) return (EINVAL); req->icount = viftable[vifi].v_pkt_in; req->ocount = viftable[vifi].v_pkt_out; req->ibytes = viftable[vifi].v_bytes_in; req->obytes = viftable[vifi].v_bytes_out; return (0); } int mrt_sysctl_vif(void *oldp, size_t *oldlenp) { caddr_t where = oldp; size_t needed, given; struct vif *vifp; vifi_t vifi; struct vifinfo vinfo; given = *oldlenp; needed = 0; for (vifi = 0; vifi < numvifs; vifi++) { vifp = &viftable[vifi]; if (in_nullhost(vifp->v_lcl_addr)) continue; vinfo.v_vifi = vifi; vinfo.v_flags = vifp->v_flags; vinfo.v_threshold = vifp->v_threshold; vinfo.v_lcl_addr = vifp->v_lcl_addr; vinfo.v_rmt_addr = vifp->v_rmt_addr; vinfo.v_pkt_in = vifp->v_pkt_in; vinfo.v_pkt_out = vifp->v_pkt_out; vinfo.v_bytes_in = vifp->v_bytes_in; vinfo.v_bytes_out = vifp->v_bytes_out; needed += sizeof(vinfo); if (where && needed <= given) { int error; error = copyout(&vinfo, where, sizeof(vinfo)); if (error) return (error); where += sizeof(vinfo); } } if (where) { *oldlenp = needed; if (given < needed) return (ENOMEM); } else *oldlenp = (11 * needed) / 10; return (0); } int mrt_sysctl_mfc(void *oldp, size_t *oldlenp) { caddr_t where = oldp; size_t needed, given; u_long i; struct mfc *m; struct mfcinfo minfo; given = *oldlenp; needed = 0; for (i = 0; mfchashtbl && i < MFCTBLSIZ; ++i) { LIST_FOREACH(m, &mfchashtbl[i], mfc_hash) { minfo.mfc_origin = m->mfc_origin; minfo.mfc_mcastgrp = m->mfc_mcastgrp; minfo.mfc_parent = m->mfc_parent; minfo.mfc_pkt_cnt = m->mfc_pkt_cnt; minfo.mfc_byte_cnt = m->mfc_byte_cnt; memcpy(minfo.mfc_ttls, m->mfc_ttls, MAXVIFS); needed += sizeof(minfo); if (where && needed <= given) { int error; error = copyout(&minfo, where, sizeof(minfo)); if (error) return (error); where += sizeof(minfo); } } } if (where) { *oldlenp = needed; if (given < needed) return (ENOMEM); } else *oldlenp = (11 * needed) / 10; return (0); } /* * Enable multicast routing */ int ip_mrouter_init(struct socket *so, struct mbuf *m) { int *v; if (so->so_type != SOCK_RAW || so->so_proto->pr_protocol != IPPROTO_IGMP) return (EOPNOTSUPP); if (m == NULL || m->m_len < sizeof(int)) return (EINVAL); v = mtod(m, int *); if (*v != 1) return (EINVAL); if (ip_mrouter != NULL) return (EADDRINUSE); ip_mrouter = so; mfchashtbl = hashinit(MFCTBLSIZ, M_MRTABLE, M_WAITOK, &mfchash); arc4random_buf(&mfchashkey, sizeof(mfchashkey)); memset(nexpire, 0, sizeof(nexpire)); #ifdef PIM pim_assert = 0; #endif timeout_set(&expire_upcalls_ch, expire_upcalls, NULL); timeout_add_msec(&expire_upcalls_ch, EXPIRE_TIMEOUT); return (0); } u_int32_t _mfchash(struct in_addr o, struct in_addr g) { SIPHASH_CTX ctx; SipHash24_Init(&ctx, &mfchashkey); SipHash24_Update(&ctx, &o.s_addr, sizeof(o.s_addr)); SipHash24_Update(&ctx, &g.s_addr, sizeof(g.s_addr)); return (SipHash24_End(&ctx) & mfchash); } /* * Disable multicast routing */ int ip_mrouter_done(void) { vifi_t vifi; struct vif *vifp; int i; int s; s = splsoftnet(); /* Clear out all the vifs currently in use. */ for (vifi = 0; vifi < numvifs; vifi++) { vifp = &viftable[vifi]; if (!in_nullhost(vifp->v_lcl_addr)) reset_vif(vifp); } numvifs = 0; mrt_api_config = 0; #ifdef PIM pim_assert = 0; #endif timeout_del(&expire_upcalls_ch); /* * Free all multicast forwarding cache entries. */ for (i = 0; i < MFCTBLSIZ; i++) { struct mfc *rt, *nrt; for (rt = LIST_FIRST(&mfchashtbl[i]); rt; rt = nrt) { nrt = LIST_NEXT(rt, mfc_hash); expire_mfc(rt); } } memset(nexpire, 0, sizeof(nexpire)); hashfree(mfchashtbl, MFCTBLSIZ, M_MRTABLE); mfchashtbl = NULL; ip_mrouter = NULL; splx(s); return (0); } void ip_mrouter_detach(struct ifnet *ifp) { int vifi, i; struct vif *vifp; struct mfc *rt; struct rtdetq *rte; /* XXX not sure about side effect to userland routing daemon */ for (vifi = 0; vifi < numvifs; vifi++) { vifp = &viftable[vifi]; if (vifp->v_ifp == ifp) reset_vif(vifp); } for (i = 0; i < MFCTBLSIZ; i++) { if (nexpire[i] == 0) continue; LIST_FOREACH(rt, &mfchashtbl[i], mfc_hash) { for (rte = rt->mfc_stall; rte; rte = rte->next) { if (rte->ifp == ifp) rte->ifp = NULL; } } } } int get_version(struct mbuf *m) { int *v = mtod(m, int *); *v = 0x0305; /* XXX !!!! */ m->m_len = sizeof(int); return (0); } #ifdef PIM /* * Set PIM assert processing global */ int set_assert(struct mbuf *m) { int *i; if (m == NULL || m->m_len < sizeof(int)) return (EINVAL); i = mtod(m, int *); pim_assert = !!*i; return (0); } /* * Get PIM assert processing global */ int get_assert(struct mbuf *m) { int *i = mtod(m, int *); *i = pim_assert; m->m_len = sizeof(int); return (0); } #endif /* * Configure API capabilities */ int set_api_config(struct mbuf *m) { int i; u_int32_t *apival; if (m == NULL || m->m_len < sizeof(u_int32_t)) return (EINVAL); apival = mtod(m, u_int32_t *); /* * We can set the API capabilities only if it is the first operation * after MRT_INIT. I.e.: * - there are no vifs installed * - pim_assert is not enabled * - the MFC table is empty */ if (numvifs > 0) { *apival = 0; return (EPERM); } #ifdef PIM if (pim_assert) { *apival = 0; return (EPERM); } #endif for (i = 0; i < MFCTBLSIZ; i++) { if (LIST_FIRST(&mfchashtbl[i]) != NULL) { *apival = 0; return (EPERM); } } mrt_api_config = *apival & mrt_api_support; *apival = mrt_api_config; return (0); } /* * Get API capabilities */ int get_api_support(struct mbuf *m) { u_int32_t *apival; if (m == NULL || m->m_len < sizeof(u_int32_t)) return (EINVAL); apival = mtod(m, u_int32_t *); *apival = mrt_api_support; return (0); } /* * Get API configured capabilities */ int get_api_config(struct mbuf *m) { u_int32_t *apival; if (m == NULL || m->m_len < sizeof(u_int32_t)) return (EINVAL); apival = mtod(m, u_int32_t *); *apival = mrt_api_config; return (0); } static struct sockaddr_in sin = { sizeof(sin), AF_INET }; /* * Add a vif to the vif table */ int add_vif(struct mbuf *m) { struct vifctl *vifcp; struct vif *vifp; struct ifaddr *ifa; struct ifnet *ifp; struct ifreq ifr; int error, s; if (m == NULL || m->m_len < sizeof(struct vifctl)) return (EINVAL); vifcp = mtod(m, struct vifctl *); if (vifcp->vifc_vifi >= MAXVIFS) return (EINVAL); if (in_nullhost(vifcp->vifc_lcl_addr)) return (EADDRNOTAVAIL); vifp = &viftable[vifcp->vifc_vifi]; if (!in_nullhost(vifp->v_lcl_addr)) return (EADDRINUSE); /* Tunnels are no longer supported use gif(4) instead. */ if (vifcp->vifc_flags & VIFF_TUNNEL) return (EOPNOTSUPP); #ifdef PIM if (vifcp->vifc_flags & VIFF_REGISTER) { /* * XXX: Because VIFF_REGISTER does not really need a valid * local interface (e.g. it could be 127.0.0.2), we don't * check its address. */ } else #endif { sin.sin_addr = vifcp->vifc_lcl_addr; ifa = ifa_ifwithaddr(sintosa(&sin), /* XXX */ 0); if (ifa == NULL) return (EADDRNOTAVAIL); } #ifdef PIM if (vifcp->vifc_flags & VIFF_REGISTER) { ifp = &multicast_register_if; if (reg_vif_num == VIFI_INVALID) { memset(ifp, 0, sizeof(*ifp)); snprintf(ifp->if_xname, sizeof ifp->if_xname, "register_vif"); ifp->if_flags = IFF_LOOPBACK; reg_vif_num = vifcp->vifc_vifi; } } else #endif { /* Use the physical interface associated with the address. */ ifp = ifa->ifa_ifp; /* Make sure the interface supports multicast. */ if ((ifp->if_flags & IFF_MULTICAST) == 0) return (EOPNOTSUPP); /* Enable promiscuous reception of all IP multicasts. */ memset(&ifr, 0, sizeof(ifr)); satosin(&ifr.ifr_addr)->sin_len = sizeof(struct sockaddr_in); satosin(&ifr.ifr_addr)->sin_family = AF_INET; satosin(&ifr.ifr_addr)->sin_addr = zeroin_addr; error = (*ifp->if_ioctl)(ifp, SIOCADDMULTI, (caddr_t)&ifr); if (error) return (error); } s = splsoftnet(); vifp->v_flags = vifcp->vifc_flags; vifp->v_threshold = vifcp->vifc_threshold; vifp->v_lcl_addr = vifcp->vifc_lcl_addr; vifp->v_rmt_addr = vifcp->vifc_rmt_addr; vifp->v_ifp = ifp; /* Initialize per vif pkt counters. */ vifp->v_pkt_in = 0; vifp->v_pkt_out = 0; vifp->v_bytes_in = 0; vifp->v_bytes_out = 0; timeout_del(&vifp->v_repq_ch); splx(s); /* Adjust numvifs up if the vifi is higher than numvifs. */ if (numvifs <= vifcp->vifc_vifi) numvifs = vifcp->vifc_vifi + 1; return (0); } void reset_vif(struct vif *vifp) { struct ifnet *ifp; struct ifreq ifr; #ifdef PIM if (vifp->v_flags & VIFF_REGISTER) { reg_vif_num = VIFI_INVALID; } else #endif { memset(&ifr, 0, sizeof(ifr)); satosin(&ifr.ifr_addr)->sin_len = sizeof(struct sockaddr_in); satosin(&ifr.ifr_addr)->sin_family = AF_INET; satosin(&ifr.ifr_addr)->sin_addr = zeroin_addr; ifp = vifp->v_ifp; (*ifp->if_ioctl)(ifp, SIOCDELMULTI, (caddr_t)&ifr); } memset(vifp, 0, sizeof(*vifp)); } /* * Delete a vif from the vif table */ int del_vif(struct mbuf *m) { vifi_t *vifip; struct vif *vifp; vifi_t vifi; int s; if (m == NULL || m->m_len < sizeof(vifi_t)) return (EINVAL); vifip = mtod(m, vifi_t *); if (*vifip >= numvifs) return (EINVAL); vifp = &viftable[*vifip]; if (in_nullhost(vifp->v_lcl_addr)) return (EADDRNOTAVAIL); s = splsoftnet(); reset_vif(vifp); /* Adjust numvifs down */ for (vifi = numvifs; vifi > 0; vifi--) if (!in_nullhost(viftable[vifi - 1].v_lcl_addr)) break; numvifs = vifi; splx(s); return (0); } void vif_delete(struct ifnet *ifp) { int i; struct vif *vifp; struct mfc *rt; struct rtdetq *rte; for (i = 0; i < numvifs; i++) { vifp = &viftable[i]; if (vifp->v_ifp == ifp) memset(vifp, 0, sizeof(*vifp)); } for (i = numvifs; i > 0; i--) if (!in_nullhost(viftable[i - 1].v_lcl_addr)) break; numvifs = i; for (i = 0; i < MFCTBLSIZ; i++) { if (nexpire[i] == 0) continue; LIST_FOREACH(rt, &mfchashtbl[i], mfc_hash) { for (rte = rt->mfc_stall; rte; rte = rte->next) { if (rte->ifp == ifp) rte->ifp = NULL; } } } } /* * update an mfc entry without resetting counters and S,G addresses. */ void update_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp) { int i; rt->mfc_parent = mfccp->mfcc_parent; for (i = 0; i < numvifs; i++) { rt->mfc_ttls[i] = mfccp->mfcc_ttls[i]; rt->mfc_flags[i] = mfccp->mfcc_flags[i] & mrt_api_config & MRT_MFC_FLAGS_ALL; } /* set the RP address */ if (mrt_api_config & MRT_MFC_RP) rt->mfc_rp = mfccp->mfcc_rp; else rt->mfc_rp = zeroin_addr; } /* * fully initialize an mfc entry from the parameter. */ void init_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp) { rt->mfc_origin = mfccp->mfcc_origin; rt->mfc_mcastgrp = mfccp->mfcc_mcastgrp; update_mfc_params(rt, mfccp); /* initialize pkt counters per src-grp */ rt->mfc_pkt_cnt = 0; rt->mfc_byte_cnt = 0; rt->mfc_wrong_if = 0; timerclear(&rt->mfc_last_assert); } void expire_mfc(struct mfc *rt) { struct rtdetq *rte, *nrte; for (rte = rt->mfc_stall; rte != NULL; rte = nrte) { nrte = rte->next; m_freem(rte->m); free(rte, M_MRTABLE, 0); } LIST_REMOVE(rt, mfc_hash); free(rt, M_MRTABLE, 0); } /* * Add an mfc entry */ int add_mfc(struct mbuf *m) { struct mfcctl2 mfcctl2; struct mfcctl2 *mfccp; struct mfc *rt; u_int32_t hash = 0; struct rtdetq *rte, *nrte; u_short nstl; int s; int mfcctl_size = sizeof(struct mfcctl); if (mrt_api_config & MRT_API_FLAGS_ALL) mfcctl_size = sizeof(struct mfcctl2); if (m == NULL || m->m_len < mfcctl_size) return (EINVAL); /* * select data size depending on API version. */ if (mrt_api_config & MRT_API_FLAGS_ALL) { struct mfcctl2 *mp2 = mtod(m, struct mfcctl2 *); bcopy(mp2, (caddr_t)&mfcctl2, sizeof(*mp2)); } else { struct mfcctl *mp = mtod(m, struct mfcctl *); bcopy(mp, (caddr_t)&mfcctl2, sizeof(*mp)); memset((caddr_t)&mfcctl2 + sizeof(struct mfcctl), 0, sizeof(mfcctl2) - sizeof(struct mfcctl)); } mfccp = &mfcctl2; s = splsoftnet(); rt = mfc_find(&mfccp->mfcc_origin, &mfccp->mfcc_mcastgrp); /* If an entry already exists, just update the fields */ if (rt) { update_mfc_params(rt, mfccp); splx(s); return (0); } /* * Find the entry for which the upcall was made and update */ nstl = 0; hash = MFCHASH(mfccp->mfcc_origin, mfccp->mfcc_mcastgrp); LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) { if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) && in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp) && rt->mfc_stall != NULL) { if (nstl++) { log(LOG_ERR, "add_mfc %s o %x g %x " "p %x dbx %p\n", "multiple kernel entries", ntohl(mfccp->mfcc_origin.s_addr), ntohl(mfccp->mfcc_mcastgrp.s_addr), mfccp->mfcc_parent, rt->mfc_stall); } rte = rt->mfc_stall; init_mfc_params(rt, mfccp); rt->mfc_stall = NULL; rt->mfc_expire = 0; /* Don't clean this guy up */ nexpire[hash]--; /* free packets Qed at the end of this entry */ for (; rte != NULL; rte = nrte) { nrte = rte->next; if (rte->ifp) { ip_mdq(rte->m, rte->ifp, rt); } m_freem(rte->m); free(rte, M_MRTABLE, 0); } } } /* * It is possible that an entry is being inserted without an upcall */ if (nstl == 0) { /* * No mfc; make a new one */ LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) { if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) && in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp)) { init_mfc_params(rt, mfccp); if (rt->mfc_expire) nexpire[hash]--; rt->mfc_expire = 0; break; /* XXX */ } } if (rt == NULL) { /* no upcall, so make a new entry */ rt = malloc(sizeof(*rt), M_MRTABLE, M_NOWAIT); if (rt == NULL) { splx(s); return (ENOBUFS); } init_mfc_params(rt, mfccp); rt->mfc_expire = 0; rt->mfc_stall = NULL; /* insert new entry at head of hash chain */ LIST_INSERT_HEAD(&mfchashtbl[hash], rt, mfc_hash); } } splx(s); return (0); } /* * Delete an mfc entry */ int del_mfc(struct mbuf *m) { struct mfcctl2 mfcctl2; struct mfcctl2 *mfccp; struct mfc *rt; int s; int mfcctl_size = sizeof(struct mfcctl); struct mfcctl *mp = mtod(m, struct mfcctl *); /* * XXX: for deleting MFC entries the information in entries * of size "struct mfcctl" is sufficient. */ if (m == NULL || m->m_len < mfcctl_size) return (EINVAL); bcopy(mp, (caddr_t)&mfcctl2, sizeof(*mp)); memset((caddr_t)&mfcctl2 + sizeof(struct mfcctl), 0, sizeof(mfcctl2) - sizeof(struct mfcctl)); mfccp = &mfcctl2; s = splsoftnet(); rt = mfc_find(&mfccp->mfcc_origin, &mfccp->mfcc_mcastgrp); if (rt == NULL) { splx(s); return (EADDRNOTAVAIL); } LIST_REMOVE(rt, mfc_hash); free(rt, M_MRTABLE, 0); splx(s); return (0); } int socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in *src) { if (s != NULL) { if (sbappendaddr(&s->so_rcv, sintosa(src), mm, NULL) != 0) { sorwakeup(s); return (0); } } m_freem(mm); return (-1); } /* * IP multicast forwarding function. This function assumes that the packet * pointed to by "ip" has arrived on (or is about to be sent to) the interface * pointed to by "ifp", and the packet is to be relayed to other networks * that have members of the packet's destination IP multicast group. * * The packet is returned unscathed to the caller, unless it is * erroneous, in which case a non-zero return value tells the caller to * discard it. */ #define IP_HDR_LEN 20 /* # bytes of fixed IP header (excluding options) */ #define TUNNEL_LEN 12 /* # bytes of IP option for tunnel encapsulation */ int ip_mforward(struct mbuf *m, struct ifnet *ifp) { struct ip *ip = mtod(m, struct ip *); struct mfc *rt; static int srctun = 0; struct mbuf *mm; int s; vifi_t vifi; if (ip->ip_hl < (IP_HDR_LEN + TUNNEL_LEN) >> 2 || ((u_char *)(ip + 1))[1] != IPOPT_LSRR) { /* * Packet arrived via a physical interface or * an encapsulated tunnel or a register_vif. */ } else { /* * Packet arrived through a source-route tunnel. * Source-route tunnels are no longer supported. */ if ((srctun++ % 1000) == 0) log(LOG_ERR, "ip_mforward: received source-routed " "packet from %x\n", ntohl(ip->ip_src.s_addr)); return (1); } /* * Don't forward a packet with time-to-live of zero or one, * or a packet destined to a local-only group. */ if (ip->ip_ttl <= 1 || IN_LOCAL_GROUP(ip->ip_dst.s_addr)) return (0); /* * Determine forwarding vifs from the forwarding cache table */ s = splsoftnet(); ++mrtstat.mrts_mfc_lookups; rt = mfc_find(&ip->ip_src, &ip->ip_dst); /* Entry exists, so forward if necessary */ if (rt != NULL) { splx(s); return (ip_mdq(m, ifp, rt)); } else { /* * If we don't have a route for packet's origin, * Make a copy of the packet & send message to routing daemon */ struct mbuf *mb0; struct rtdetq *rte; u_int32_t hash; int hlen = ip->ip_hl << 2; ++mrtstat.mrts_mfc_misses; mrtstat.mrts_no_route++; /* * Allocate mbufs early so that we don't do extra work if we are * just going to fail anyway. Make sure to pullup the header so * that other people can't step on it. */ rte = malloc(sizeof(*rte), M_MRTABLE, M_NOWAIT); if (rte == NULL) { splx(s); return (ENOBUFS); } mb0 = m_copym(m, 0, M_COPYALL, M_NOWAIT); M_PULLUP(mb0, hlen); if (mb0 == NULL) { free(rte, M_MRTABLE, 0); splx(s); return (ENOBUFS); } /* is there an upcall waiting for this flow? */ hash = MFCHASH(ip->ip_src, ip->ip_dst); LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) { if (in_hosteq(ip->ip_src, rt->mfc_origin) && in_hosteq(ip->ip_dst, rt->mfc_mcastgrp) && rt->mfc_stall != NULL) break; } if (rt == NULL) { int i; struct igmpmsg *im; /* * Locate the vifi for the incoming interface for * this packet. * If none found, drop packet. */ for (vifi = 0; vifi < numvifs && viftable[vifi].v_ifp != ifp; vifi++) ; if (vifi >= numvifs) /* vif not found, drop packet */ goto non_fatal; /* no upcall, so make a new entry */ rt = malloc(sizeof(*rt), M_MRTABLE, M_NOWAIT); if (rt == NULL) goto fail; /* * Make a copy of the header to send to the user level * process */ mm = m_copym(m, 0, hlen, M_NOWAIT); M_PULLUP(mm, hlen); if (mm == NULL) goto fail1; /* * Send message to routing daemon to install * a route into the kernel table */ im = mtod(mm, struct igmpmsg *); im->im_msgtype = IGMPMSG_NOCACHE; im->im_mbz = 0; im->im_vif = vifi; mrtstat.mrts_upcalls++; sin.sin_addr = ip->ip_src; if (socket_send(ip_mrouter, mm, &sin) < 0) { log(LOG_WARNING, "ip_mforward: ip_mrouter " "socket queue full\n"); ++mrtstat.mrts_upq_sockfull; fail1: free(rt, M_MRTABLE, 0); fail: free(rte, M_MRTABLE, 0); m_freem(mb0); splx(s); return (ENOBUFS); } /* insert new entry at head of hash chain */ rt->mfc_origin = ip->ip_src; rt->mfc_mcastgrp = ip->ip_dst; rt->mfc_pkt_cnt = 0; rt->mfc_byte_cnt = 0; rt->mfc_wrong_if = 0; rt->mfc_expire = UPCALL_EXPIRE; nexpire[hash]++; for (i = 0; i < numvifs; i++) { rt->mfc_ttls[i] = 0; rt->mfc_flags[i] = 0; } rt->mfc_parent = -1; /* clear the RP address */ rt->mfc_rp = zeroin_addr; /* link into table */ LIST_INSERT_HEAD(&mfchashtbl[hash], rt, mfc_hash); /* Add this entry to the end of the queue */ rt->mfc_stall = rte; } else { /* determine if q has overflowed */ struct rtdetq **p; int npkts = 0; /* * XXX ouch! we need to append to the list, but we * only have a pointer to the front, so we have to * scan the entire list every time. */ for (p = &rt->mfc_stall; *p != NULL; p = &(*p)->next) if (++npkts > MAX_UPQ) { mrtstat.mrts_upq_ovflw++; non_fatal: free(rte, M_MRTABLE, 0); m_freem(mb0); splx(s); return (0); } /* Add this entry to the end of the queue */ *p = rte; } rte->next = NULL; rte->m = mb0; rte->ifp = ifp; splx(s); return (0); } } /*ARGSUSED*/ void expire_upcalls(void *v) { int i; int s; s = splsoftnet(); for (i = 0; i < MFCTBLSIZ; i++) { struct mfc *rt, *nrt; if (nexpire[i] == 0) continue; for (rt = LIST_FIRST(&mfchashtbl[i]); rt; rt = nrt) { nrt = LIST_NEXT(rt, mfc_hash); if (rt->mfc_expire == 0 || --rt->mfc_expire > 0) continue; nexpire[i]--; ++mrtstat.mrts_cache_cleanups; expire_mfc(rt); } } splx(s); timeout_add_msec(&expire_upcalls_ch, EXPIRE_TIMEOUT); } /* * Packet forwarding routine once entry in the cache is made */ int ip_mdq(struct mbuf *m, struct ifnet *ifp, struct mfc *rt) { struct ip *ip = mtod(m, struct ip *); vifi_t vifi; struct vif *vifp; int plen = ntohs(ip->ip_len) - (ip->ip_hl << 2); /* * Don't forward if it didn't arrive from the parent vif for its origin. */ vifi = rt->mfc_parent; if ((vifi >= numvifs) || (viftable[vifi].v_ifp != ifp)) { /* came in the wrong interface */ ++mrtstat.mrts_wrong_if; ++rt->mfc_wrong_if; #ifdef PIM /* * If we are doing PIM assert processing, send a message * to the routing daemon. * * XXX: A PIM-SM router needs the WRONGVIF detection so it * can complete the SPT switch, regardless of the type * of interface (broadcast media, GRE tunnel, etc). */ if (pim_assert && (vifi < numvifs) && viftable[vifi].v_ifp) { struct timeval now; u_int32_t delta; if (ifp == &multicast_register_if) pimstat.pims_rcv_registers_wrongiif++; /* Get vifi for the incoming packet */ for (vifi = 0; vifi < numvifs && viftable[vifi].v_ifp != ifp; vifi++) ; if (vifi >= numvifs) { /* The iif is not found: ignore the packet. */ return (0); } if (rt->mfc_flags[vifi] & MRT_MFC_FLAGS_DISABLE_WRONGVIF) { /* WRONGVIF disabled: ignore the packet */ return (0); } microtime(&now); TV_DELTA(rt->mfc_last_assert, now, delta); if (delta > ASSERT_MSG_TIME) { struct igmpmsg *im; int hlen = ip->ip_hl << 2; struct mbuf *mm = m_copym(m, 0, hlen, M_NOWAIT); M_PULLUP(mm, hlen); if (mm == NULL) return (ENOBUFS); rt->mfc_last_assert = now; im = mtod(mm, struct igmpmsg *); im->im_msgtype = IGMPMSG_WRONGVIF; im->im_mbz = 0; im->im_vif = vifi; mrtstat.mrts_upcalls++; sin.sin_addr = im->im_src; if (socket_send(ip_mrouter, mm, &sin) < 0) { log(LOG_WARNING, "ip_mforward: " "ip_mrouter socket queue full\n"); ++mrtstat.mrts_upq_sockfull; return (ENOBUFS); } } } #endif return (0); } /* If I sourced this packet, it counts as output, else it was input. */ if (in_hosteq(ip->ip_src, viftable[vifi].v_lcl_addr)) { viftable[vifi].v_pkt_out++; viftable[vifi].v_bytes_out += plen; } else { viftable[vifi].v_pkt_in++; viftable[vifi].v_bytes_in += plen; } rt->mfc_pkt_cnt++; rt->mfc_byte_cnt += plen; /* * For each vif, decide if a copy of the packet should be forwarded. * Forward if: * - the ttl exceeds the vif's threshold * - there are group members downstream on interface */ for (vifp = viftable, vifi = 0; vifi < numvifs; vifp++, vifi++) if ((rt->mfc_ttls[vifi] > 0) && (ip->ip_ttl > rt->mfc_ttls[vifi])) { vifp->v_pkt_out++; vifp->v_bytes_out += plen; #ifdef PIM if (vifp->v_flags & VIFF_REGISTER) pim_register_send(ip, vifp, m, rt); else #endif phyint_send(ip, vifp, m); } return (0); } void phyint_send(struct ip *ip, struct vif *vifp, struct mbuf *m) { struct mbuf *mb_copy; int hlen = ip->ip_hl << 2; /* * Make a new reference to the packet; make sure that * the IP header is actually copied, not just referenced, * so that ip_output() only scribbles on the copy. */ mb_copy = m_copym(m, 0, M_COPYALL, M_NOWAIT); M_PULLUP(mb_copy, hlen); if (mb_copy == NULL) return; send_packet(vifp, mb_copy); } void send_packet(struct vif *vifp, struct mbuf *m) { struct ip_moptions imo; int s; /* * if physical interface option, extract the options * and then send */ imo.imo_ifidx = vifp->v_ifp->if_index; imo.imo_ttl = mtod(m, struct ip *)->ip_ttl - IPTTLDEC; imo.imo_loop = 1; s = splsoftnet(); ip_output(m, NULL, NULL, IP_FORWARDING, &imo, NULL, 0); splx(s); } #ifdef PIM /* * Send the packet up to the user daemon, or eventually do kernel encapsulation */ int pim_register_send(struct ip *ip, struct vif *vifp, struct mbuf *m, struct mfc *rt) { struct mbuf *mb_copy, *mm; mb_copy = pim_register_prepare(ip, m); if (mb_copy == NULL) return (ENOBUFS); /* * Send all the fragments. Note that the mbuf for each fragment * is freed by the sending machinery. */ for (mm = mb_copy; mm; mm = mb_copy) { mb_copy = mm->m_nextpkt; mm->m_nextpkt = NULL; mm = m_pullup(mm, sizeof(struct ip)); if (mm != NULL) { ip = mtod(mm, struct ip *); if ((mrt_api_config & MRT_MFC_RP) && !in_nullhost(rt->mfc_rp)) { pim_register_send_rp(ip, vifp, mm, rt); } else { pim_register_send_upcall(ip, vifp, mm, rt); } } } return (0); } /* * Return a copy of the data packet that is ready for PIM Register * encapsulation. * XXX: Note that in the returned copy the IP header is a valid one. */ struct mbuf * pim_register_prepare(struct ip *ip, struct mbuf *m) { struct mbuf *mb_copy = NULL; int mtu; in_proto_cksum_out(m, NULL); /* * Copy the old packet & pullup its IP header into the * new mbuf so we can modify it. */ mb_copy = m_copym(m, 0, M_COPYALL, M_NOWAIT); if (mb_copy == NULL) return (NULL); mb_copy = m_pullup(mb_copy, ip->ip_hl << 2); if (mb_copy == NULL) return (NULL); /* take care of the TTL */ ip = mtod(mb_copy, struct ip *); --ip->ip_ttl; /* Compute the MTU after the PIM Register encapsulation */ mtu = 0xffff - sizeof(pim_encap_iphdr) - sizeof(pim_encap_pimhdr); if (ntohs(ip->ip_len) <= mtu) { /* Turn the IP header into a valid one */ ip->ip_sum = 0; ip->ip_sum = in_cksum(mb_copy, ip->ip_hl << 2); } else { /* Fragment the packet */ if (ip_fragment(mb_copy, NULL, mtu) != 0) { /* XXX: mb_copy was freed by ip_fragment() */ return (NULL); } } return (mb_copy); } /* * Send an upcall with the data packet to the user-level process. */ int pim_register_send_upcall(struct ip *ip, struct vif *vifp, struct mbuf *mb_copy, struct mfc *rt) { struct mbuf *mb_first; int len = ntohs(ip->ip_len); struct igmpmsg *im; struct sockaddr_in k_igmpsrc = { sizeof k_igmpsrc, AF_INET }; /* Add a new mbuf with an upcall header */ MGETHDR(mb_first, M_DONTWAIT, MT_HEADER); if (mb_first == NULL) { m_freem(mb_copy); return (ENOBUFS); } mb_first->m_data += max_linkhdr; mb_first->m_pkthdr.len = len + sizeof(struct igmpmsg); mb_first->m_len = sizeof(struct igmpmsg); mb_first->m_next = mb_copy; /* Send message to routing daemon */ im = mtod(mb_first, struct igmpmsg *); im->im_msgtype = IGMPMSG_WHOLEPKT; im->im_mbz = 0; im->im_vif = vifp - viftable; im->im_src = ip->ip_src; im->im_dst = ip->ip_dst; k_igmpsrc.sin_addr = ip->ip_src; mrtstat.mrts_upcalls++; if (socket_send(ip_mrouter, mb_first, &k_igmpsrc) < 0) { ++mrtstat.mrts_upq_sockfull; return (ENOBUFS); } /* Keep statistics */ pimstat.pims_snd_registers_msgs++; pimstat.pims_snd_registers_bytes += len; return (0); } /* * Encapsulate the data packet in PIM Register message and send it to the RP. */ int pim_register_send_rp(struct ip *ip, struct vif *vifp, struct mbuf *mb_copy, struct mfc *rt) { struct mbuf *mb_first; struct ip *ip_outer; struct pim_encap_pimhdr *pimhdr; int len = ntohs(ip->ip_len); vifi_t vifi = rt->mfc_parent; if ((vifi >= numvifs) || in_nullhost(viftable[vifi].v_lcl_addr)) { m_freem(mb_copy); return (EADDRNOTAVAIL); /* The iif vif is invalid */ } /* Add a new mbuf with the encapsulating header */ MGETHDR(mb_first, M_DONTWAIT, MT_HEADER); if (mb_first == NULL) { m_freem(mb_copy); return (ENOBUFS); } mb_first->m_data += max_linkhdr; mb_first->m_len = sizeof(pim_encap_iphdr) + sizeof(pim_encap_pimhdr); mb_first->m_next = mb_copy; mb_first->m_pkthdr.len = len + mb_first->m_len; /* Fill in the encapsulating IP and PIM header */ ip_outer = mtod(mb_first, struct ip *); *ip_outer = pim_encap_iphdr; ip_outer->ip_id = htons(ip_randomid()); ip_outer->ip_len = htons(len + sizeof(pim_encap_iphdr) + sizeof(pim_encap_pimhdr)); ip_outer->ip_src = viftable[vifi].v_lcl_addr; ip_outer->ip_dst = rt->mfc_rp; /* * Copy the inner header TOS to the outer header, and take care of the * IP_DF bit. */ ip_outer->ip_tos = ip->ip_tos; if (ntohs(ip->ip_off) & IP_DF) ip_outer->ip_off |= htons(IP_DF); pimhdr = (struct pim_encap_pimhdr *)((caddr_t)ip_outer + sizeof(pim_encap_iphdr)); *pimhdr = pim_encap_pimhdr; /* If the iif crosses a border, set the Border-bit */ if (rt->mfc_flags[vifi] & MRT_MFC_FLAGS_BORDER_VIF & mrt_api_config) pimhdr->flags |= htonl(PIM_BORDER_REGISTER); mb_first->m_data += sizeof(pim_encap_iphdr); pimhdr->pim.pim_cksum = in_cksum(mb_first, sizeof(pim_encap_pimhdr)); mb_first->m_data -= sizeof(pim_encap_iphdr); send_packet(vifp, mb_first); /* Keep statistics */ pimstat.pims_snd_registers_msgs++; pimstat.pims_snd_registers_bytes += len; return (0); } /* * PIM-SMv2 and PIM-DM messages processing. * Receives and verifies the PIM control messages, and passes them * up to the listening socket, using rip_input(). * The only message with special processing is the PIM_REGISTER message * (used by PIM-SM): the PIM header is stripped off, and the inner packet * is passed to if_simloop(). */ void pim_input(struct mbuf *m, ...) { struct ip *ip = mtod(m, struct ip *); struct pim *pim; int minlen; int datalen; int ip_tos; int iphlen; va_list ap; va_start(ap, m); iphlen = va_arg(ap, int); va_end(ap); datalen = ntohs(ip->ip_len) - iphlen; /* Keep statistics */ pimstat.pims_rcv_total_msgs++; pimstat.pims_rcv_total_bytes += datalen; /* Validate lengths */ if (datalen < PIM_MINLEN) { pimstat.pims_rcv_tooshort++; log(LOG_ERR, "pim_input: packet size too small %d from %lx\n", datalen, (u_long)ip->ip_src.s_addr); m_freem(m); return; } /* * If the packet is at least as big as a REGISTER, go agead * and grab the PIM REGISTER header size, to avoid another * possible m_pullup() later. * * PIM_MINLEN == pimhdr + u_int32_t == 4 + 4 = 8 * PIM_REG_MINLEN == pimhdr + reghdr + encap_iphdr == 4 + 4 + 20 = 28 */ minlen = iphlen + (datalen >= PIM_REG_MINLEN ? PIM_REG_MINLEN : PIM_MINLEN); /* * Get the IP and PIM headers in contiguous memory, and * possibly the PIM REGISTER header. */ if ((m->m_flags & M_EXT || m->m_len < minlen) && (m = m_pullup(m, minlen)) == NULL) { log(LOG_ERR, "pim_input: m_pullup failure\n"); return; } /* m_pullup() may have given us a new mbuf so reset ip. */ ip = mtod(m, struct ip *); ip_tos = ip->ip_tos; /* adjust mbuf to point to the PIM header */ m->m_data += iphlen; m->m_len -= iphlen; pim = mtod(m, struct pim *); /* * Validate checksum. If PIM REGISTER, exclude the data packet. * * XXX: some older PIMv2 implementations don't make this distinction, * so for compatibility reason perform the checksum over part of the * message, and if error, then over the whole message. */ if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER && in_cksum(m, PIM_MINLEN) == 0) { /* do nothing, checksum okay */ } else if (in_cksum(m, datalen)) { pimstat.pims_rcv_badsum++; m_freem(m); return; } /* PIM version check */ if (PIM_VT_V(pim->pim_vt) < PIM_VERSION) { pimstat.pims_rcv_badversion++; log(LOG_ERR, "pim_input: incorrect version %d, expecting %d\n", PIM_VT_V(pim->pim_vt), PIM_VERSION); m_freem(m); return; } /* restore mbuf back to the outer IP */ m->m_data -= iphlen; m->m_len += iphlen; if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER) { /* * Since this is a REGISTER, we'll make a copy of the register * headers ip + pim + u_int32 + encap_ip, to be passed up to the * routing daemon. */ int s; struct sockaddr_in dst = { sizeof(dst), AF_INET }; struct mbuf *mcp; struct ip *encap_ip; u_int32_t *reghdr; struct ifnet *vifp; s = splsoftnet(); if ((reg_vif_num >= numvifs) || (reg_vif_num == VIFI_INVALID)) { splx(s); m_freem(m); return; } /* XXX need refcnt? */ vifp = viftable[reg_vif_num].v_ifp; splx(s); /* Validate length */ if (datalen < PIM_REG_MINLEN) { pimstat.pims_rcv_tooshort++; pimstat.pims_rcv_badregisters++; log(LOG_ERR, "pim_input: register packet size " "too small %d from %lx\n", datalen, (u_long)ip->ip_src.s_addr); m_freem(m); return; } reghdr = (u_int32_t *)(pim + 1); encap_ip = (struct ip *)(reghdr + 1); /* verify the version number of the inner packet */ if (encap_ip->ip_v != IPVERSION) { pimstat.pims_rcv_badregisters++; m_freem(m); return; } /* verify the inner packet is destined to a mcast group */ if (!IN_MULTICAST(encap_ip->ip_dst.s_addr)) { pimstat.pims_rcv_badregisters++; m_freem(m); return; } /* If a NULL_REGISTER, pass it to the daemon */ if ((ntohl(*reghdr) & PIM_NULL_REGISTER)) goto pim_input_to_daemon; /* * Copy the TOS from the outer IP header to the inner * IP header. */ if (encap_ip->ip_tos != ip_tos) { /* Outer TOS -> inner TOS */ encap_ip->ip_tos = ip_tos; /* Recompute the inner header checksum. Sigh... */ /* adjust mbuf to point to the inner IP header */ m->m_data += (iphlen + PIM_MINLEN); m->m_len -= (iphlen + PIM_MINLEN); encap_ip->ip_sum = 0; encap_ip->ip_sum = in_cksum(m, encap_ip->ip_hl << 2); /* restore mbuf to point back to the outer IP header */ m->m_data -= (iphlen + PIM_MINLEN); m->m_len += (iphlen + PIM_MINLEN); } /* * Decapsulate the inner IP packet and loopback to forward it * as a normal multicast packet. Also, make a copy of the * outer_iphdr + pimhdr + reghdr + encap_iphdr * to pass to the daemon later, so it can take the appropriate * actions (e.g., send back PIM_REGISTER_STOP). * XXX: here m->m_data points to the outer IP header. */ mcp = m_copym(m, 0, iphlen + PIM_REG_MINLEN, M_NOWAIT); if (mcp == NULL) { log(LOG_ERR, "pim_input: pim register: could not " "copy register head\n"); m_freem(m); return; } /* Keep statistics */ /* XXX: registers_bytes include only the encap. mcast pkt */ pimstat.pims_rcv_registers_msgs++; pimstat.pims_rcv_registers_bytes += ntohs(encap_ip->ip_len); /* forward the inner ip packet; point m_data at the inner ip. */ m_adj(m, iphlen + PIM_MINLEN); /* NB: vifp was collected above; can it change on us? */ if_input_local(vifp, m, dst.sin_family); /* prepare the register head to send to the mrouting daemon */ m = mcp; } pim_input_to_daemon: /* * Pass the PIM message up to the daemon; if it is a Register message, * pass the 'head' only up to the daemon. This includes the * outer IP header, PIM header, PIM-Register header and the * inner IP header. * XXX: the outer IP header pkt size of a Register is not adjust to * reflect the fact that the inner multicast data is truncated. */ rip_input(m); return; } /* * Sysctl for pim variables. */ int pim_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { /* All sysctl names at this level are terminal. */ if (namelen != 1) return (ENOTDIR); switch (name[0]) { case PIMCTL_STATS: if (newp != NULL) return (EPERM); return (sysctl_struct(oldp, oldlenp, newp, newlen, &pimstat, sizeof(pimstat))); default: return (ENOPROTOOPT); } /* NOTREACHED */ } #endif /* PIM */