/* $OpenBSD: route6.c,v 1.10 2003/06/11 02:54:02 itojun Exp $ */ /* $KAME: route6.c,v 1.22 2000/12/03 00:54:00 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. */ #include <sys/param.h> #include <sys/mbuf.h> #include <sys/socket.h> #include <sys/systm.h> #include <net/if.h> #include <netinet/in.h> #include <netinet6/in6_var.h> #include <netinet/ip6.h> #include <netinet6/ip6_var.h> #include <netinet/icmp6.h> static int ip6_rthdr0(struct mbuf *, struct ip6_hdr *, struct ip6_rthdr0 *); int route6_input(mp, offp, proto) struct mbuf **mp; int *offp, proto; /* proto is unused */ { struct ip6_hdr *ip6; struct mbuf *m = *mp; struct ip6_rthdr *rh; int off = *offp, rhlen; ip6 = mtod(m, struct ip6_hdr *); IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh)); if (rh == NULL) { ip6stat.ip6s_tooshort++; return IPPROTO_DONE; } switch (rh->ip6r_type) { case IPV6_RTHDR_TYPE_0: rhlen = (rh->ip6r_len + 1) << 3; /* * note on option length: * maximum rhlen: 2048 * max mbuf m_pulldown can handle: MCLBYTES == usually 2048 * so, here we are assuming that m_pulldown can handle * rhlen == 2048 case. this may not be a good thing to * assume - we may want to avoid pulling it up altogether. */ IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, rhlen); if (rh == NULL) { ip6stat.ip6s_tooshort++; return IPPROTO_DONE; } if (ip6_rthdr0(m, ip6, (struct ip6_rthdr0 *)rh)) return (IPPROTO_DONE); break; default: /* unknown routing type */ if (rh->ip6r_segleft == 0) { rhlen = (rh->ip6r_len + 1) << 3; break; /* Final dst. Just ignore the header. */ } ip6stat.ip6s_badoptions++; icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (caddr_t)&rh->ip6r_type - (caddr_t)ip6); return (IPPROTO_DONE); } *offp += rhlen; return (rh->ip6r_nxt); } /* * Type0 routing header processing * * RFC2292 backward compatibility warning: no support for strict/loose bitmap, * as it was dropped between RFC1883 and RFC2460. */ static int ip6_rthdr0(m, ip6, rh0) struct mbuf *m; struct ip6_hdr *ip6; struct ip6_rthdr0 *rh0; { int addrs, index; struct in6_addr *nextaddr, tmpaddr; if (rh0->ip6r0_segleft == 0) return (0); if (rh0->ip6r0_len % 2 #ifdef COMPAT_RFC1883 || rh0->ip6r0_len > 46 #endif ) { /* * Type 0 routing header can't contain more than 23 addresses. * RFC 2462: this limitation was removed since strict/loose * bitmap field was deleted. */ ip6stat.ip6s_badoptions++; icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (caddr_t)&rh0->ip6r0_len - (caddr_t)ip6); return (-1); } if ((addrs = rh0->ip6r0_len / 2) < rh0->ip6r0_segleft) { ip6stat.ip6s_badoptions++; icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (caddr_t)&rh0->ip6r0_segleft - (caddr_t)ip6); return (-1); } index = addrs - rh0->ip6r0_segleft; rh0->ip6r0_segleft--; nextaddr = ((struct in6_addr *)(rh0 + 1)) + index; /* * reject invalid addresses. be proactive about malicious use of * IPv4 mapped/compat address. * XXX need more checks? */ if (IN6_IS_ADDR_MULTICAST(nextaddr) || IN6_IS_ADDR_UNSPECIFIED(nextaddr) || IN6_IS_ADDR_V4MAPPED(nextaddr) || IN6_IS_ADDR_V4COMPAT(nextaddr)) { ip6stat.ip6s_badoptions++; goto bad; } if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst) || IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst) || IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { ip6stat.ip6s_badoptions++; goto bad; } /* * Swap the IPv6 destination address and nextaddr. Forward the packet. */ tmpaddr = *nextaddr; *nextaddr = ip6->ip6_dst; if (IN6_IS_ADDR_LINKLOCAL(nextaddr)) nextaddr->s6_addr16[1] = 0; ip6->ip6_dst = tmpaddr; if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) ip6->ip6_dst.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index); #ifdef COMPAT_RFC1883 if (rh0->ip6r0_slmap[index / 8] & (1 << (7 - (index % 8)))) ip6_forward(m, IPV6_SRCRT_NEIGHBOR); else ip6_forward(m, IPV6_SRCRT_NOTNEIGHBOR); #else ip6_forward(m, 1); #endif return (-1); /* m would be freed in ip6_forward() */ bad: m_freem(m); return (-1); }