#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#include <netinet/in_pcb.h>
#if IPSEC
#include <netinet6/ipsec.h>
#if INET6
#include <netinet6/ipsec6.h>
#endif
#include <netkey/key.h>
extern int ipsec_bypass;
#endif
extern lck_mtx_t *ip6_mutex;
#include <netinet6/ip6_fw.h>
#include <net/net_osdep.h>
#if PF
#include <net/pfvar.h>
#endif
void
ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
int srcrt, int locked)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct sockaddr_in6 *dst;
struct rtentry *rt;
int error, type = 0, code = 0;
struct mbuf *mcopy = NULL;
struct ifnet *ifp, *origifp;
#if IPSEC
struct secpolicy *sp = NULL;
#endif
struct timeval timenow;
int tunneledv4 = 0;
getmicrotime(&timenow);
#if IPSEC
if (ipsec_bypass == 0) {
if (ipsec6_in_reject(m, NULL)) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_polvio);
m_freem(m);
return;
}
}
#endif
if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 ||
IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
ip6stat.ip6s_cantforward++;
if (ip6_log_time + ip6_log_interval < timenow.tv_sec) {
ip6_log_time = timenow.tv_sec;
log(LOG_DEBUG,
"cannot forward "
"from %s to %s nxt %d received on %s\n",
ip6_sprintf(&ip6->ip6_src),
ip6_sprintf(&ip6->ip6_dst),
ip6->ip6_nxt,
if_name(m->m_pkthdr.rcvif));
}
m_freem(m);
return;
}
if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
if (locked)
lck_mtx_unlock(ip6_mutex);
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
if (locked)
lck_mtx_lock(ip6_mutex);
return;
}
ip6->ip6_hlim -= IPV6_HLIMDEC;
mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
#if IPSEC
if (ipsec_bypass != 0)
goto skip_ipsec;
sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, IP_FORWARDING,
&error);
if (sp == NULL) {
IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
ip6stat.ip6s_cantforward++;
if (mcopy) {
#if 0
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
error = 0;
switch (sp->policy) {
case IPSEC_POLICY_DISCARD:
case IPSEC_POLICY_GENERATE:
IPSEC_STAT_INCREMENT(ipsec6stat.out_polvio);
ip6stat.ip6s_cantforward++;
key_freesp(sp, KEY_SADB_UNLOCKED);
if (mcopy) {
#if 0
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
key_freesp(sp, KEY_SADB_UNLOCKED);
goto skip_ipsec;
case IPSEC_POLICY_IPSEC:
if (sp->req == NULL) {
printf("ip6_forward: No IPsec request specified.\n");
ip6stat.ip6s_cantforward++;
key_freesp(sp, KEY_SADB_UNLOCKED);
if (mcopy) {
#if 0
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
break;
case IPSEC_POLICY_ENTRUST:
default:
printf("ip6_forward: Invalid policy found. %d\n", sp->policy);
key_freesp(sp, KEY_SADB_UNLOCKED);
goto skip_ipsec;
}
{
struct ipsec_output_state state;
bzero(&state, sizeof(state));
state.m = m;
state.ro = NULL;
state.dst = NULL;
if (locked)
lck_mtx_unlock(ip6_mutex);
error = ipsec6_output_tunnel(&state, sp, 0, &tunneledv4);
if (locked)
lck_mtx_lock(ip6_mutex);
key_freesp(sp, KEY_SADB_UNLOCKED);
if (tunneledv4)
return;
m = state.m;
if (error) {
switch (error) {
case EHOSTUNREACH:
case ENETUNREACH:
case EMSGSIZE:
case ENOBUFS:
case ENOMEM:
break;
default:
printf("ip6_output (ipsec): error code %d\n", error);
case ENOENT:
break;
}
ip6stat.ip6s_cantforward++;
if (mcopy) {
#if 0
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
}
skip_ipsec:
#endif
if (locked)
lck_mtx_assert(ip6_mutex, LCK_MTX_ASSERT_OWNED);
dst = (struct sockaddr_in6 *)&ip6forward_rt->ro_dst;
if ((rt = ip6forward_rt->ro_rt) != NULL) {
RT_LOCK(rt);
RT_ADDREF_LOCKED(rt);
}
if (!srcrt) {
if (rt == NULL || !(rt->rt_flags & RTF_UP) ||
rt->generation_id != route_generation) {
if (rt != NULL) {
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
rtfree(rt);
ip6forward_rt->ro_rt = NULL;
}
rtalloc_ign((struct route *)ip6forward_rt,
RTF_PRCLONING);
if ((rt = ip6forward_rt->ro_rt) != NULL) {
RT_LOCK(rt);
RT_ADDREF_LOCKED(rt);
}
}
if (rt == NULL) {
ip6stat.ip6s_noroute++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy) {
if (locked)
lck_mtx_unlock(ip6_mutex);
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
if (locked)
lck_mtx_lock(ip6_mutex);
}
m_freem(m);
return;
}
RT_LOCK_ASSERT_HELD(rt);
} else if (rt == NULL || !(rt->rt_flags & RTF_UP) ||
!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr) ||
rt->generation_id != route_generation) {
if (rt != NULL) {
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
rtfree(rt);
ip6forward_rt->ro_rt = NULL;
}
bzero(dst, sizeof(*dst));
dst->sin6_len = sizeof(struct sockaddr_in6);
dst->sin6_family = AF_INET6;
dst->sin6_addr = ip6->ip6_dst;
rtalloc_ign((struct route *)ip6forward_rt, RTF_PRCLONING);
if ((rt = ip6forward_rt->ro_rt) == NULL) {
ip6stat.ip6s_noroute++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy) {
if (locked)
lck_mtx_unlock(ip6_mutex);
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
if (locked)
lck_mtx_lock(ip6_mutex);
}
m_freem(m);
return;
}
RT_LOCK(rt);
RT_ADDREF_LOCKED(rt);
}
if (in6_addr2scopeid(m->m_pkthdr.rcvif, &ip6->ip6_src) !=
in6_addr2scopeid(rt->rt_ifp, &ip6->ip6_src)) {
ip6stat.ip6s_cantforward++;
ip6stat.ip6s_badscope++;
in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard);
if (ip6_log_time + ip6_log_interval < timenow.tv_sec) {
ip6_log_time = timenow.tv_sec;
log(LOG_DEBUG,
"cannot forward "
"src %s, dst %s, nxt %d, rcvif %s, outif %s\n",
ip6_sprintf(&ip6->ip6_src),
ip6_sprintf(&ip6->ip6_dst),
ip6->ip6_nxt,
if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp));
}
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
if (mcopy) {
if (locked)
lck_mtx_unlock(ip6_mutex);
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
if (locked)
lck_mtx_lock(ip6_mutex);
}
m_freem(m);
return;
}
if (m->m_pkthdr.len > rt->rt_ifp->if_mtu) {
in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig);
if (mcopy) {
uint32_t mtu;
#if IPSEC
struct secpolicy *sp2;
int ipsecerror;
size_t ipsechdrsiz;
#endif
mtu = rt->rt_ifp->if_mtu;
#if IPSEC
sp2 = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
IP_FORWARDING, &ipsecerror);
if (sp2) {
ipsechdrsiz = ipsec6_hdrsiz(mcopy,
IPSEC_DIR_OUTBOUND, NULL);
if (ipsechdrsiz < mtu)
mtu -= ipsechdrsiz;
key_freesp(sp2, KEY_SADB_UNLOCKED);
}
if (mtu < IPV6_MMTU)
mtu = IPV6_MMTU;
#endif
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
if (locked)
lck_mtx_unlock(ip6_mutex);
icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
if (locked)
lck_mtx_lock(ip6_mutex);
} else {
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
}
m_freem(m);
return;
}
if (rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in6 *)rt->rt_gateway;
if (rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt &&
(rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0) {
if ((rt->rt_ifp->if_flags & IFF_POINTOPOINT) != 0) {
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
if (locked)
lck_mtx_unlock(ip6_mutex);
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADDR, 0);
if (locked)
lck_mtx_lock(ip6_mutex);
m_freem(m);
return;
}
type = ND_REDIRECT;
}
#if IPFW2
if (ip6_fw_enable && ip6_fw_chk_ptr) {
u_short port = 0;
ifp = rt->rt_ifp;
RT_UNLOCK(rt);
if (ip6_fw_chk_ptr(&ip6, ifp, &port, &m)) {
m_freem(m);
goto freecopy;
}
if (!m) {
goto freecopy;
}
RT_LOCK(rt);
}
#endif
if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
#if 1
if (0)
#else
if ((rt->rt_flags & (RTF_BLACKHOLE|RTF_REJECT)) == 0)
#endif
{
printf("ip6_forward: outgoing interface is loopback. "
"src %s, dst %s, nxt %d, rcvif %s, outif %s\n",
ip6_sprintf(&ip6->ip6_src),
ip6_sprintf(&ip6->ip6_dst),
ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif),
if_name(rt->rt_ifp));
}
origifp = m->m_pkthdr.rcvif;
}
else
origifp = rt->rt_ifp;
#ifndef SCOPEDROUTING
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
#endif
ifp = rt->rt_ifp;
RT_UNLOCK(rt);
#if PF
if (locked)
lck_mtx_unlock(ip6_mutex);
error = pf_af_hook(ifp, NULL, &m, AF_INET6, FALSE);
if (locked)
lck_mtx_lock(ip6_mutex);
if (error) {
if (m != NULL) {
panic("%s: unexpected packet %p\n", __func__, m);
}
goto senderr;
}
ip6 = mtod(m, struct ip6_hdr *);
#endif
error = nd6_output(ifp, origifp, m, dst, rt, locked);
if (error) {
in6_ifstat_inc(ifp, ifs6_out_discard);
ip6stat.ip6s_cantforward++;
} else {
ip6stat.ip6s_forward++;
in6_ifstat_inc(ifp, ifs6_out_forward);
if (type)
ip6stat.ip6s_redirectsent++;
else {
if (mcopy) {
goto freecopy;
}
}
}
#if PF
senderr:
#endif
if (mcopy == NULL) {
RT_REMREF(rt);
return;
}
switch (error) {
case 0:
#if 1
if (type == ND_REDIRECT) {
icmp6_redirect_output(mcopy, rt);
RT_REMREF(rt);
return;
}
#endif
goto freecopy;
case EMSGSIZE:
goto freecopy;
case ENOBUFS:
goto freecopy;
case ENETUNREACH:
case EHOSTUNREACH:
case ENETDOWN:
case EHOSTDOWN:
default:
type = ICMP6_DST_UNREACH;
code = ICMP6_DST_UNREACH_ADDR;
break;
}
if (locked)
lck_mtx_unlock(ip6_mutex);
icmp6_error(mcopy, type, code, 0);
if (locked)
lck_mtx_lock(ip6_mutex);
RT_REMREF(rt);
return;
freecopy:
m_freem(mcopy);
RT_REMREF(rt);
return;
}