/* $OpenBSD: raw_ip6.c,v 1.43 2011/05/13 14:31:17 oga Exp $ */ /* $KAME: raw_ip6.c,v 1.69 2001/03/04 15:55:44 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * 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 project 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 PROJECT 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 PROJECT 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. */ /* * Copyright (c) 1982, 1986, 1988, 1993 * The Regents of the University of California. All rights reserved. * * 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. * * @(#)raw_ip.c 8.2 (Berkeley) 1/4/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef MROUTING #include #endif #include #include #include #include #include #include #ifdef ENABLE_DEFAULT_SCOPE #include #endif #include #include #include "faith.h" /* * Raw interface to IP6 protocol. */ /* inpcb members */ #define in6pcb inpcb #define in6p_laddr inp_laddr6 #define in6p_faddr inp_faddr6 #define in6p_icmp6filt inp_icmp6filt #define in6p_route inp_route6 #define in6p_socket inp_socket #define in6p_flags inp_flags #define in6p_moptions inp_moptions6 #define in6p_outputopts inp_outputopts6 #define in6p_ip6 inp_ipv6 #define in6p_flowinfo inp_flowinfo #define in6p_sp inp_sp #define in6p_next inp_next #define in6p_prev inp_prev /* macro names */ #define sotoin6pcb sotoinpcb /* function names */ #define in6_pcbdetach in_pcbdetach #define in6_rtchange in_rtchange struct inpcbtable rawin6pcbtable; #define ifatoia6(ifa) ((struct in6_ifaddr *)(ifa)) struct rip6stat rip6stat; /* * Initialize raw connection block queue. */ void rip6_init() { in_pcbinit(&rawin6pcbtable, 1); } /* * Setup generic address and protocol structures * for raw_input routine, then pass them along with * mbuf chain. */ int rip6_input(struct mbuf **mp, int *offp, int proto) { struct mbuf *m = *mp; struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct in6pcb *in6p; struct in6pcb *last = NULL; struct sockaddr_in6 rip6src; struct mbuf *opts = NULL; rip6stat.rip6s_ipackets++; #if defined(NFAITH) && 0 < NFAITH if (m->m_pkthdr.rcvif) { if (m->m_pkthdr.rcvif->if_type == IFT_FAITH) { /* send icmp6 host unreach? */ m_freem(m); return IPPROTO_DONE; } } #endif /* Be proactive about malicious use of IPv4 mapped address */ if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { /* XXX stat */ m_freem(m); return IPPROTO_DONE; } bzero(&rip6src, sizeof(rip6src)); rip6src.sin6_len = sizeof(struct sockaddr_in6); rip6src.sin6_family = AF_INET6; /* KAME hack: recover scopeid */ (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); CIRCLEQ_FOREACH(in6p, &rawin6pcbtable.inpt_queue, inp_queue) { if (in6p->in6p_socket->so_state & SS_CANTRCVMORE) continue; if (!(in6p->in6p_flags & INP_IPV6)) continue; if (in6p->in6p_ip6.ip6_nxt && in6p->in6p_ip6.ip6_nxt != proto) continue; if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) continue; if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) continue; if (in6p->in6p_cksum != -1) { rip6stat.rip6s_isum++; if (in6_cksum(m, proto, *offp, m->m_pkthdr.len - *offp)) { rip6stat.rip6s_badsum++; continue; } } if (last) { struct mbuf *n; if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { if (last->in6p_flags & IN6P_CONTROLOPTS) ip6_savecontrol(last, n, &opts); /* strip intermediate headers */ m_adj(n, *offp); if (sbappendaddr(&last->in6p_socket->so_rcv, (struct sockaddr *)&rip6src, n, opts) == 0) { /* should notify about lost packet */ m_freem(n); if (opts) m_freem(opts); rip6stat.rip6s_fullsock++; } else sorwakeup(last->in6p_socket); opts = NULL; } } last = in6p; } if (last) { if (last->in6p_flags & IN6P_CONTROLOPTS) ip6_savecontrol(last, m, &opts); /* strip intermediate headers */ m_adj(m, *offp); if (sbappendaddr(&last->in6p_socket->so_rcv, (struct sockaddr *)&rip6src, m, opts) == 0) { m_freem(m); if (opts) m_freem(opts); rip6stat.rip6s_fullsock++; } else sorwakeup(last->in6p_socket); } else { rip6stat.rip6s_nosock++; if (m->m_flags & M_MCAST) rip6stat.rip6s_nosockmcast++; if (proto == IPPROTO_NONE) m_freem(m); else { u_int8_t *prvnxtp = ip6_get_prevhdr(m, *offp); /* XXX */ in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_protounknown); icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_NEXTHEADER, prvnxtp - mtod(m, u_int8_t *)); } ip6stat.ip6s_delivered--; } return IPPROTO_DONE; } void rip6_ctlinput(int cmd, struct sockaddr *sa, void *d) { struct ip6_hdr *ip6; struct ip6ctlparam *ip6cp = NULL; const struct sockaddr_in6 *sa6_src = NULL; void *cmdarg; void (*notify)(struct in6pcb *, int) = in6_rtchange; int nxt; if (sa->sa_family != AF_INET6 || sa->sa_len != sizeof(struct sockaddr_in6)) return; if ((unsigned)cmd >= PRC_NCMDS) return; if (PRC_IS_REDIRECT(cmd)) notify = in6_rtchange, d = NULL; else if (cmd == PRC_HOSTDEAD) d = NULL; else if (cmd == PRC_MSGSIZE) ; /* special code is present, see below */ else if (inet6ctlerrmap[cmd] == 0) return; /* if the parameter is from icmp6, decode it. */ if (d != NULL) { ip6cp = (struct ip6ctlparam *)d; ip6 = ip6cp->ip6c_ip6; cmdarg = ip6cp->ip6c_cmdarg; sa6_src = ip6cp->ip6c_src; nxt = ip6cp->ip6c_nxt; } else { ip6 = NULL; cmdarg = NULL; sa6_src = &sa6_any; nxt = -1; } if (ip6 && cmd == PRC_MSGSIZE) { struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)sa; int valid = 0; struct in6pcb *in6p; /* * Check to see if we have a valid raw IPv6 socket * corresponding to the address in the ICMPv6 message * payload, and the protocol (ip6_nxt) meets the socket. * XXX chase extension headers, or pass final nxt value * from icmp6_notify_error() */ in6p = NULL; in6p = in6_pcbhashlookup(&rawin6pcbtable, &sa6->sin6_addr, 0, (struct in6_addr *)&sa6_src->sin6_addr, 0); #if 0 if (!in6p) { /* * As the use of sendto(2) is fairly popular, * we may want to allow non-connected pcb too. * But it could be too weak against attacks... * We should at least check if the local * address (= s) is really ours. */ in6p = in_pcblookup(&rawin6pcbtable, &sa6->sin6_addr, 0, (struct in6_addr *)&sa6_src->sin6_addr, 0, INPLOOKUP_WILDCARD | INPLOOKUP_IPV6); } #endif if (in6p && in6p->in6p_ip6.ip6_nxt && in6p->in6p_ip6.ip6_nxt == nxt) valid++; /* * Depending on the value of "valid" and routing table * size (mtudisc_{hi,lo}wat), we will: * - recalculate the new MTU and create the * corresponding routing entry, or * - ignore the MTU change notification. */ icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); /* * regardless of if we called icmp6_mtudisc_update(), * we need to call in6_pcbnotify(), to notify path * MTU change to the userland (2292bis-02), because * some unconnected sockets may share the same * destination and want to know the path MTU. */ } (void) in6_pcbnotify(&rawin6pcbtable, sa, 0, (struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify); } /* * Generate IPv6 header and pass packet to ip6_output. * Tack on options user may have setup with control call. */ int rip6_output(struct mbuf *m, ...) { struct socket *so; struct sockaddr_in6 *dstsock; struct mbuf *control; struct in6_addr *dst; struct ip6_hdr *ip6; struct in6pcb *in6p; u_int plen = m->m_pkthdr.len; int error = 0; struct ip6_pktopts opt, *optp = NULL, *origoptp; struct ifnet *oifp = NULL; int type, code; /* for ICMPv6 output statistics only */ int priv = 0; va_list ap; int flags; va_start(ap, m); so = va_arg(ap, struct socket *); dstsock = va_arg(ap, struct sockaddr_in6 *); control = va_arg(ap, struct mbuf *); va_end(ap); in6p = sotoin6pcb(so); priv = 0; if ((so->so_state & SS_PRIV) != 0) priv = 1; dst = &dstsock->sin6_addr; if (control) { if ((error = ip6_setpktopts(control, &opt, in6p->in6p_outputopts, priv, so->so_proto->pr_protocol)) != 0) goto bad; optp = &opt; } else optp = in6p->in6p_outputopts; /* * For an ICMPv6 packet, we should know its type and code * to update statistics. */ if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) { struct icmp6_hdr *icmp6; if (m->m_len < sizeof(struct icmp6_hdr) && (m = m_pullup(m, sizeof(struct icmp6_hdr))) == NULL) { error = ENOBUFS; goto bad; } icmp6 = mtod(m, struct icmp6_hdr *); type = icmp6->icmp6_type; code = icmp6->icmp6_code; } M_PREPEND(m, sizeof(*ip6), M_DONTWAIT); if (!m) { error = ENOBUFS; goto bad; } ip6 = mtod(m, struct ip6_hdr *); /* * Next header might not be ICMP6 but use its pseudo header anyway. */ ip6->ip6_dst = *dst; /* KAME hack: embed scopeid */ origoptp = in6p->in6p_outputopts; in6p->in6p_outputopts = optp; if (in6_embedscope(&ip6->ip6_dst, dstsock, in6p, &oifp) != 0) { error = EINVAL; goto bad; } in6p->in6p_outputopts = origoptp; /* * Source address selection. */ { struct in6_addr *in6a; if ((in6a = in6_selectsrc(dstsock, optp, in6p->in6p_moptions, &in6p->in6p_route, &in6p->in6p_laddr, &error)) == 0) { if (error == 0) error = EADDRNOTAVAIL; goto bad; } ip6->ip6_src = *in6a; if (in6p->in6p_route.ro_rt && in6p->in6p_route.ro_rt->rt_flags & RTF_UP) oifp = in6p->in6p_route.ro_rt->rt_ifp; } ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK; ip6->ip6_vfc &= ~IPV6_VERSION_MASK; ip6->ip6_vfc |= IPV6_VERSION; #if 0 /* ip6_plen will be filled in ip6_output. */ ip6->ip6_plen = htons((u_short)plen); #endif ip6->ip6_nxt = in6p->in6p_ip6.ip6_nxt; ip6->ip6_hlim = in6_selecthlim(in6p, oifp); if (so->so_proto->pr_protocol == IPPROTO_ICMPV6 || in6p->in6p_cksum != -1) { struct mbuf *n; int off; u_int16_t *sump; int sumoff; /* compute checksum */ if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) off = offsetof(struct icmp6_hdr, icmp6_cksum); else off = in6p->in6p_cksum; if (plen < off + 1) { error = EINVAL; goto bad; } off += sizeof(struct ip6_hdr); n = m_pulldown(m, off, sizeof(*sump), &sumoff); if (n == NULL) { m = NULL; error = ENOBUFS; goto bad; } sump = (u_int16_t *)(mtod(n, caddr_t) + sumoff); *sump = 0; *sump = in6_cksum(m, ip6->ip6_nxt, sizeof(*ip6), plen); } flags = 0; if (in6p->in6p_flags & IN6P_MINMTU) flags |= IPV6_MINMTU; error = ip6_output(m, optp, &in6p->in6p_route, flags, in6p->in6p_moptions, &oifp, in6p); if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) { if (oifp) icmp6_ifoutstat_inc(oifp, type, code); icmp6stat.icp6s_outhist[type]++; } else rip6stat.rip6s_opackets++; goto freectl; bad: if (m) m_freem(m); freectl: if (control) { ip6_clearpktopts(&opt, -1); m_freem(control); } return (error); } /* * Raw IPv6 socket option processing. */ int rip6_ctloutput(int op, struct socket *so, int level, int optname, struct mbuf **mp) { #ifdef MROUTING int error = 0; #endif switch (level) { case IPPROTO_IPV6: switch (optname) { #ifdef MROUTING case MRT6_INIT: case MRT6_DONE: case MRT6_ADD_MIF: case MRT6_DEL_MIF: case MRT6_ADD_MFC: case MRT6_DEL_MFC: case MRT6_PIM: if (op == PRCO_SETOPT) { error = ip6_mrouter_set(optname, so, *mp); if (*mp) (void)m_free(*mp); } else if (op == PRCO_GETOPT) error = ip6_mrouter_get(optname, so, mp); else error = EINVAL; return (error); #endif case IPV6_CHECKSUM: return (ip6_raw_ctloutput(op, so, level, optname, mp)); default: return (ip6_ctloutput(op, so, level, optname, mp)); } case IPPROTO_ICMPV6: /* * XXX: is it better to call icmp6_ctloutput() directly * from protosw? */ return (icmp6_ctloutput(op, so, level, optname, mp)); default: if (op == PRCO_SETOPT && *mp) m_free(*mp); return EINVAL; } } extern u_long rip6_sendspace; extern u_long rip6_recvspace; int rip6_usrreq(struct socket *so, int req, struct mbuf *m, struct mbuf *nam, struct mbuf *control, struct proc *p) { struct in6pcb *in6p = sotoin6pcb(so); int s; int error = 0; int priv; priv = 0; if ((so->so_state & SS_PRIV) != 0) priv++; if (req == PRU_CONTROL) return (in6_control(so, (u_long)m, (caddr_t)nam, (struct ifnet *)control, p)); switch (req) { case PRU_ATTACH: if (in6p) panic("rip6_attach"); if (!priv) { error = EACCES; break; } s = splsoftnet(); if ((error = soreserve(so, rip6_sendspace, rip6_recvspace)) != 0) { splx(s); break; } if ((error = in_pcballoc(so, &rawin6pcbtable)) != 0) { splx(s); break; } splx(s); in6p = sotoin6pcb(so); in6p->in6p_ip6.ip6_nxt = (long)nam; in6p->in6p_cksum = -1; in6p->in6p_icmp6filt = malloc(sizeof(struct icmp6_filter), M_PCB, M_NOWAIT); if (in6p->in6p_icmp6filt == NULL) { in6_pcbdetach(in6p); error = ENOMEM; break; } ICMP6_FILTER_SETPASSALL(in6p->in6p_icmp6filt); break; case PRU_DISCONNECT: if ((so->so_state & SS_ISCONNECTED) == 0) { error = ENOTCONN; break; } in6p->in6p_faddr = in6addr_any; so->so_state &= ~SS_ISCONNECTED; /* XXX */ break; case PRU_ABORT: soisdisconnected(so); /* FALLTHROUGH */ case PRU_DETACH: if (in6p == 0) panic("rip6_detach"); #ifdef MROUTING if (so == ip6_mrouter) ip6_mrouter_done(); #endif /* xxx: RSVP */ if (in6p->in6p_icmp6filt) { free(in6p->in6p_icmp6filt, M_PCB); in6p->in6p_icmp6filt = NULL; } in6_pcbdetach(in6p); break; case PRU_BIND: { struct sockaddr_in6 *addr = mtod(nam, struct sockaddr_in6 *); struct ifaddr *ia = NULL; if (nam->m_len != sizeof(*addr)) { error = EINVAL; break; } if (TAILQ_EMPTY(&ifnet) || (addr->sin6_family != AF_INET6)) { error = EADDRNOTAVAIL; break; } #ifdef ENABLE_DEFAULT_SCOPE if (addr->sin6_scope_id == 0) /* not change if specified */ addr->sin6_scope_id = scope6_addr2default(&addr->sin6_addr); #endif /* * we don't support mapped address here, it would confuse * users so reject it */ if (IN6_IS_ADDR_V4MAPPED(&addr->sin6_addr)) { error = EADDRNOTAVAIL; break; } /* * Currently, ifa_ifwithaddr tends to fail for a link-local * address, since it implicitly expects that the link ID * for the address is embedded in the sin6_addr part. * For now, we'd rather keep this "as is". We'll eventually fix * this in a more natural way. */ if (!IN6_IS_ADDR_UNSPECIFIED(&addr->sin6_addr) && (ia = ifa_ifwithaddr((struct sockaddr *)addr, /* XXX */ 0)) == 0) { error = EADDRNOTAVAIL; break; } if (ia && ((struct in6_ifaddr *)ia)->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY| IN6_IFF_DETACHED|IN6_IFF_DEPRECATED)) { error = EADDRNOTAVAIL; break; } in6p->in6p_laddr = addr->sin6_addr; break; } case PRU_CONNECT: { struct sockaddr_in6 *addr = mtod(nam, struct sockaddr_in6 *); struct in6_addr *in6a = NULL; #ifdef ENABLE_DEFAULT_SCOPE struct sockaddr_in6 sin6; #endif if (nam->m_len != sizeof(*addr)) { error = EINVAL; break; } if (TAILQ_EMPTY(&ifnet)) { error = EADDRNOTAVAIL; break; } if (addr->sin6_family != AF_INET6) { error = EAFNOSUPPORT; break; } #ifdef ENABLE_DEFAULT_SCOPE if (addr->sin6_scope_id == 0) { /* protect *addr */ sin6 = *addr; addr = &sin6; addr->sin6_scope_id = scope6_addr2default(&addr->sin6_addr); } #endif /* Source address selection. XXX: need pcblookup? */ in6a = in6_selectsrc(addr, in6p->in6p_outputopts, in6p->in6p_moptions, &in6p->in6p_route, &in6p->in6p_laddr, &error); if (in6a == NULL) { if (error == 0) error = EADDRNOTAVAIL; break; } in6p->in6p_laddr = *in6a; in6p->in6p_faddr = addr->sin6_addr; soisconnected(so); break; } case PRU_CONNECT2: error = EOPNOTSUPP; break; /* * Mark the connection as being incapable of futther input. */ case PRU_SHUTDOWN: socantsendmore(so); break; /* * Ship a packet out. The appropriate raw output * routine handles any messaging necessary. */ case PRU_SEND: { struct sockaddr_in6 tmp; struct sockaddr_in6 *dst; /* always copy sockaddr to avoid overwrites */ if (so->so_state & SS_ISCONNECTED) { if (nam) { error = EISCONN; break; } /* XXX */ bzero(&tmp, sizeof(tmp)); tmp.sin6_family = AF_INET6; tmp.sin6_len = sizeof(struct sockaddr_in6); bcopy(&in6p->in6p_faddr, &tmp.sin6_addr, sizeof(struct in6_addr)); dst = &tmp; } else { if (nam == NULL) { error = ENOTCONN; break; } if (nam->m_len != sizeof(tmp)) { error = EINVAL; break; } tmp = *mtod(nam, struct sockaddr_in6 *); dst = &tmp; if (dst->sin6_family != AF_INET6) { error = EAFNOSUPPORT; break; } } #ifdef ENABLE_DEFAULT_SCOPE if (dst->sin6_scope_id == 0) { dst->sin6_scope_id = scope6_addr2default(&dst->sin6_addr); } #endif error = rip6_output(m, so, dst, control); m = NULL; break; } case PRU_SENSE: /* * stat: don't bother with a blocksize */ return (0); /* * Not supported. */ case PRU_RCVOOB: case PRU_RCVD: case PRU_LISTEN: case PRU_ACCEPT: case PRU_SENDOOB: error = EOPNOTSUPP; break; case PRU_SOCKADDR: in6_setsockaddr(in6p, nam); break; case PRU_PEERADDR: in6_setpeeraddr(in6p, nam); break; default: panic("rip6_usrreq"); } if (m != NULL) m_freem(m); return (error); } int rip6_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 RIPV6CTL_STATS: if (newp != NULL) return (EPERM); return (sysctl_struct(oldp, oldlenp, newp, newlen, &rip6stat, sizeof(rip6stat))); default: return (EOPNOTSUPP); } /* NOTREACHED */ }