static int
ip6_findroute(struct nhop6_basic *pnh, const struct sockaddr_in6 *dst,
struct mbuf *m)
{
if (fib6_lookup_nh_basic(M_GETFIB(m), &dst->sin6_addr,
dst->sin6_scope_id, 0, dst->sin6_flowinfo, pnh) != 0) {
IP6STAT_INC(ip6s_noroute);
IP6STAT_INC(ip6s_cantforward);
icmp6_error(m, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
return (EHOSTUNREACH);
}
if (pnh->nh_flags & NHF_BLACKHOLE) {
IP6STAT_INC(ip6s_cantforward);
m_freem(m);
return (EHOSTUNREACH);
}
if (pnh->nh_flags & NHF_REJECT) {
IP6STAT_INC(ip6s_cantforward);
icmp6_error(m, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_REJECT, 0);
return (EHOSTUNREACH);
}
return (0);
}
int
route6_input(struct mbuf **mp, int *offp, int proto)
{
#pragma unused(proto)
struct ip6_hdr *ip6;
struct mbuf *m = *mp;
struct ip6_rthdr *rh;
int off = *offp, rhlen;
#ifdef notyet
struct ip6aux *ip6a;
ip6a = ip6_findaux(m);
if (ip6a) {
/* XXX reject home-address option before rthdr */
if (ip6a->ip6a_flags & IP6A_SWAP) {
ip6stat.ip6s_badoptions++;
m_freem(m);
return IPPROTO_DONE;
}
}
#endif /* notyet */
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, sizeof(*rh), return IPPROTO_DONE);
/* Expect 32-bit aligned data pointer on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
ip6 = mtod(m, struct ip6_hdr *);
rh = (struct ip6_rthdr *)((caddr_t)ip6 + off);
#else
/* Expect 32-bit aligned data pointer on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
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);
}
#endif
switch (rh->ip6r_type) {
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);
}
int
route6_input(struct mbuf **mp, int *offp, int proto)
{
struct ip6_hdr *ip6;
struct mbuf *m = *mp;
struct ip6_rthdr *rh;
int off = *offp, rhlen;
#ifdef __notyet__
struct ip6aux *ip6a;
ip6a = ip6_findaux(m);
if (ip6a) {
/* XXX reject home-address option before rthdr */
if (ip6a->ip6a_flags & IP6A_SWAP) {
IP6STAT_INC(ip6s_badoptions);
m_freem(m);
return IPPROTO_DONE;
}
}
#endif
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, sizeof(*rh), IPPROTO_DONE);
ip6 = mtod(m, struct ip6_hdr *);
rh = (struct ip6_rthdr *)((caddr_t)ip6 + off);
#else
ip6 = mtod(m, struct ip6_hdr *);
IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh));
if (rh == NULL) {
IP6STAT_INC(ip6s_tooshort);
return IPPROTO_DONE;
}
#endif
/*
* While this switch may look gratuitous, leave it in
* in favour of RH2 implementations, etc.
*/
switch (rh->ip6r_type) {
default:
/* Unknown routing header type. */
if (rh->ip6r_segleft == 0) {
rhlen = (rh->ip6r_len + 1) << 3;
break; /* Final dst. Just ignore the header. */
}
IP6STAT_INC(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);
}
/*
* Send any deferred ICMP param problem error messages; caller must not be
* holding ip6qlock and is expected to have saved the per-packet parameter
* value via frag6_save_context().
*/
static void
frag6_icmp6_paramprob_error(struct fq6_head *diq6)
{
lck_mtx_assert(&ip6qlock, LCK_MTX_ASSERT_NOTOWNED);
if (!MBUFQ_EMPTY(diq6)) {
struct mbuf *merr, *merr_tmp;
int param;
MBUFQ_FOREACH_SAFE(merr, diq6, merr_tmp) {
MBUFQ_REMOVE(diq6, merr);
MBUFQ_NEXT(merr) = NULL;
param = frag6_restore_context(merr);
frag6_scrub_context(merr);
icmp6_error(merr, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER, param);
}
}
/**
* Processing of IPv6 packets.
*
* @param eth Ethernet header
* @param packet Packet data
*
* @return 0 for success
* @return 1 for failure
*/
int ipv6(struct s_ethernet *eth, char *packet)
{
struct s_ipv6 *ip;
char *payload;
/* load data into structures */
ip = (struct s_ipv6 *) packet;
payload = packet + sizeof(struct s_ipv6);
/* test if this packet belongs to us */
if (memcmp(&wrapsix_ipv6_prefix, &ip->ip_dest, 12) != 0 &&
memcmp(&ndp_multicast_addr, &ip->ip_dest, 13) != 0) {
return 1;
}
/* check and decrease hop limit */
if (ip->hop_limit <= 1) {
/* deny this error for error ICMP messages */
if (ip->next_header != IPPROTO_ICMPV6 || payload[0] & 0x80) {
/* code 0 = hl exceeded in transmit */
icmp6_error(eth->src, ip->ip_src, ICMPV6_TIME_EXCEEDED,
0, (unsigned char *) packet,
htons(ip->len) + sizeof(struct s_ipv6));
}
return 1;
} else {
ip->hop_limit--;
}
switch (ip->next_header) {
case IPPROTO_TCP:
log_debug("IPv6 Protocol: TCP");
return tcp_ipv6(eth, ip, payload);
case IPPROTO_UDP:
log_debug("IPv6 Protocol: UDP");
return udp_ipv6(eth, ip, payload);
case IPPROTO_ICMPV6:
log_debug("IPv6 Protocol: ICMP");
return icmp_ipv6(eth, ip, payload);
default:
log_debug("IPv6 Protocol: unknown [%d/0x%x]",
ip->next_header, ip->next_header);
return 1;
}
}
ER_UINT
ip6_unknown_opt (T_NET_BUF *input, uint8_t *opt)
{
switch (IP6OPT_TYPE(*opt)) {
case IP6OPT_TYPE_SKIP: /* 無視する。 */
return *(opt + 1);
break;
case IP6OPT_TYPE_ICMP: /* 破棄して、マルチキャストでなければ ICMP を返送する。 */
if (IN6_IS_ADDR_MULTICAST(&GET_IP6_HDR(input)->dst))
return IP6_OPT_RET_ERR;
/* no break; */
case IP6OPT_TYPE_FORCEICMP: /* 破棄して、ICMP を返送する。 */
icmp6_error(input, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_OPTION,
(opt - input->buf) - IF_HDR_SIZE);
return IP6_OPT_RET_REL;
break;
/*case IP6OPT_TYPE_DISCARD: データグラムを破棄する。 */
}
return IP6_OPT_RET_ERR;
}
int
route6_input(struct mbuf **mp, int *offp, int proto)
{
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:
/*
* RFC 5095 specifies to handle routing header type 0
* the same way as an unrecognised routing type.
*/
/* FALLTHROUGH */
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);
}
/*
* Fragment input
*/
int
frag6_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp, *t;
struct ip6_hdr *ip6;
struct ip6_frag *ip6f;
struct ip6q *q6;
struct ip6asfrag *af6, *ip6af, *af6dwn;
struct in6_ifaddr *ia;
int offset = *offp, nxt, i, next;
int first_frag = 0;
int fragoff, frgpartlen; /* must be larger than u_int16_t */
struct ifnet *dstifp;
u_int8_t ecn, ecn0;
#if 0
char ip6buf[INET6_ADDRSTRLEN];
#endif
ip6 = mtod(m, struct ip6_hdr *);
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, offset, sizeof(struct ip6_frag), IPPROTO_DONE);
ip6f = (struct ip6_frag *)((caddr_t)ip6 + offset);
#else
IP6_EXTHDR_GET(ip6f, struct ip6_frag *, m, offset, sizeof(*ip6f));
if (ip6f == NULL)
return (IPPROTO_DONE);
#endif
dstifp = NULL;
/* find the destination interface of the packet. */
ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */);
if (ia != NULL) {
dstifp = ia->ia_ifp;
ifa_free(&ia->ia_ifa);
}
/* jumbo payload can't contain a fragment header */
if (ip6->ip6_plen == 0) {
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, offset);
in6_ifstat_inc(dstifp, ifs6_reass_fail);
return IPPROTO_DONE;
}
/*
* check whether fragment packet's fragment length is
* multiple of 8 octets.
* sizeof(struct ip6_frag) == 8
* sizeof(struct ip6_hdr) = 40
*/
if ((ip6f->ip6f_offlg & IP6F_MORE_FRAG) &&
(((ntohs(ip6->ip6_plen) - offset) & 0x7) != 0)) {
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
offsetof(struct ip6_hdr, ip6_plen));
in6_ifstat_inc(dstifp, ifs6_reass_fail);
return IPPROTO_DONE;
}
IP6STAT_INC(ip6s_fragments);
in6_ifstat_inc(dstifp, ifs6_reass_reqd);
/* offset now points to data portion */
offset += sizeof(struct ip6_frag);
/*
* RFC 6946: Handle "atomic" fragments (offset and m bit set to 0)
* upfront, unrelated to any reassembly. Just skip the fragment header.
*/
if ((ip6f->ip6f_offlg & ~IP6F_RESERVED_MASK) == 0) {
/* XXX-BZ we want dedicated counters for this. */
IP6STAT_INC(ip6s_reassembled);
in6_ifstat_inc(dstifp, ifs6_reass_ok);
*offp = offset;
return (ip6f->ip6f_nxt);
}
IP6Q_LOCK();
/*
* Enforce upper bound on number of fragments.
* If maxfrag is 0, never accept fragments.
* If maxfrag is -1, accept all fragments without limitation.
*/
if (V_ip6_maxfrags < 0)
;
else if (V_frag6_nfrags >= (u_int)V_ip6_maxfrags)
goto dropfrag;
for (q6 = V_ip6q.ip6q_next; q6 != &V_ip6q; q6 = q6->ip6q_next)
if (ip6f->ip6f_ident == q6->ip6q_ident &&
IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, &q6->ip6q_src) &&
IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &q6->ip6q_dst)
#ifdef MAC
&& mac_ip6q_match(m, q6)
#endif
)
break;
if (q6 == &V_ip6q) {
/*
* the first fragment to arrive, create a reassembly queue.
*/
first_frag = 1;
/*
* Enforce upper bound on number of fragmented packets
* for which we attempt reassembly;
* If maxfragpackets is 0, never accept fragments.
* If maxfragpackets is -1, accept all fragments without
* limitation.
*/
if (V_ip6_maxfragpackets < 0)
;
else if (V_frag6_nfragpackets >= (u_int)V_ip6_maxfragpackets)
goto dropfrag;
V_frag6_nfragpackets++;
q6 = (struct ip6q *)malloc(sizeof(struct ip6q), M_FTABLE,
M_NOWAIT);
if (q6 == NULL)
goto dropfrag;
bzero(q6, sizeof(*q6));
#ifdef MAC
if (mac_ip6q_init(q6, M_NOWAIT) != 0) {
free(q6, M_FTABLE);
goto dropfrag;
}
mac_ip6q_create(m, q6);
#endif
frag6_insque(q6, &V_ip6q);
/* ip6q_nxt will be filled afterwards, from 1st fragment */
q6->ip6q_down = q6->ip6q_up = (struct ip6asfrag *)q6;
#ifdef notyet
q6->ip6q_nxtp = (u_char *)nxtp;
#endif
q6->ip6q_ident = ip6f->ip6f_ident;
q6->ip6q_ttl = IPV6_FRAGTTL;
q6->ip6q_src = ip6->ip6_src;
q6->ip6q_dst = ip6->ip6_dst;
q6->ip6q_ecn =
(ntohl(ip6->ip6_flow) >> 20) & IPTOS_ECN_MASK;
q6->ip6q_unfrglen = -1; /* The 1st fragment has not arrived. */
q6->ip6q_nfrag = 0;
}
static int
ip6_fw_chk(struct ip6_hdr **pip6,
struct ifnet *oif, struct mbuf **m)
{
struct ip6_fw_chain *chain;
struct ip6_fw *rule = NULL;
struct ip6_hdr *ip6 = *pip6;
struct ifnet *const rif = (*m)->m_pkthdr.rcvif;
u_short offset = 0;
int off = sizeof(struct ip6_hdr), nxt = ip6->ip6_nxt;
u_short src_port, dst_port;
#ifdef IP6FW_DIVERT_RESTART
u_int16_t skipto = 0;
#else
u_int16_t ignport = 0;
#endif
/*
* Go down the chain, looking for enlightment
* #ifdef IP6FW_DIVERT_RESTART
* If we've been asked to start at a given rule immediatly, do so.
* #endif
*/
chain = LIST_FIRST(&ip6_fw_chain);
#ifdef IP6FW_DIVERT_RESTART
if (skipto) {
if (skipto >= 65535)
goto dropit;
while (chain && (chain->rule->fw_number <= skipto)) {
chain = LIST_NEXT(chain, chain);
}
if (! chain) goto dropit;
}
#endif /* IP6FW_DIVERT_RESTART */
for (; chain; chain = LIST_NEXT(chain, chain)) {
struct ip6_fw *const f = chain->rule;
if (oif) {
/* Check direction outbound */
if (!(f->fw_flg & IPV6_FW_F_OUT))
continue;
} else {
/* Check direction inbound */
if (!(f->fw_flg & IPV6_FW_F_IN))
continue;
}
#define IN6_ARE_ADDR_MASKEQUAL(x,y,z) (\
(((x)->s6_addr32[0] & (y)->s6_addr32[0]) == (z)->s6_addr32[0]) && \
(((x)->s6_addr32[1] & (y)->s6_addr32[1]) == (z)->s6_addr32[1]) && \
(((x)->s6_addr32[2] & (y)->s6_addr32[2]) == (z)->s6_addr32[2]) && \
(((x)->s6_addr32[3] & (y)->s6_addr32[3]) == (z)->s6_addr32[3]))
/* If src-addr doesn't match, not this rule. */
if (((f->fw_flg & IPV6_FW_F_INVSRC) != 0) ^
(!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_src,&f->fw_smsk,&f->fw_src)))
continue;
/* If dest-addr doesn't match, not this rule. */
if (((f->fw_flg & IPV6_FW_F_INVDST) != 0) ^
(!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_dst,&f->fw_dmsk,&f->fw_dst)))
continue;
#undef IN6_ARE_ADDR_MASKEQUAL
/* Interface check */
if ((f->fw_flg & IF6_FW_F_VIAHACK) == IF6_FW_F_VIAHACK) {
struct ifnet *const iface = oif ? oif : rif;
/* Backwards compatibility hack for "via" */
if (!iface || !iface_match(iface,
&f->fw_in_if, f->fw_flg & IPV6_FW_F_OIFNAME))
continue;
} else {
/* Check receive interface */
if ((f->fw_flg & IPV6_FW_F_IIFACE)
&& (!rif || !iface_match(rif,
&f->fw_in_if, f->fw_flg & IPV6_FW_F_IIFNAME)))
continue;
/* Check outgoing interface */
if ((f->fw_flg & IPV6_FW_F_OIFACE)
&& (!oif || !iface_match(oif,
&f->fw_out_if, f->fw_flg & IPV6_FW_F_OIFNAME)))
continue;
}
/* Check IP options */
if (!ip6opts_match(&ip6, f, m, &off, &nxt, &offset))
continue;
/* Fragments */
if ((f->fw_flg & IPV6_FW_F_FRAG) && !offset)
continue;
/* Check protocol; if wildcard, match */
if (f->fw_prot == IPPROTO_IPV6)
goto got_match;
/* If different, don't match */
if (nxt != f->fw_prot)
continue;
#define PULLUP_TO(len) do { \
if ((*m)->m_len < (len) \
&& (*m = m_pullup(*m, (len))) == 0) { \
goto dropit; \
} \
*pip6 = ip6 = mtod(*m, struct ip6_hdr *); \
} while (/*CONSTCOND*/ 0)
/* Protocol specific checks */
switch (nxt) {
case IPPROTO_TCP:
{
struct tcphdr *tcp6;
if (offset == 1) { /* cf. RFC 1858 */
PULLUP_TO(off + 4); /* XXX ? */
goto bogusfrag;
}
if (offset != 0) {
/*
* TCP flags and ports aren't available in this
* packet -- if this rule specified either one,
* we consider the rule a non-match.
*/
if (f->fw_nports != 0 ||
f->fw_tcpf != f->fw_tcpnf)
continue;
break;
}
PULLUP_TO(off + 14);
tcp6 = (struct tcphdr *) ((caddr_t)ip6 + off);
if (((f->fw_tcpf != f->fw_tcpnf) ||
(f->fw_ipflg & IPV6_FW_IF_TCPEST)) &&
!tcp6flg_match(tcp6, f))
continue;
src_port = ntohs(tcp6->th_sport);
dst_port = ntohs(tcp6->th_dport);
goto check_ports;
}
case IPPROTO_UDP:
{
struct udphdr *udp;
if (offset != 0) {
/*
* Port specification is unavailable -- if this
* rule specifies a port, we consider the rule
* a non-match.
*/
if (f->fw_nports != 0)
continue;
break;
}
PULLUP_TO(off + 4);
udp = (struct udphdr *) ((caddr_t)ip6 + off);
src_port = ntohs(udp->uh_sport);
dst_port = ntohs(udp->uh_dport);
check_ports:
if (!port_match6(&f->fw_pts[0],
IPV6_FW_GETNSRCP(f), src_port,
f->fw_flg & IPV6_FW_F_SRNG))
continue;
if (!port_match6(&f->fw_pts[IPV6_FW_GETNSRCP(f)],
IPV6_FW_GETNDSTP(f), dst_port,
f->fw_flg & IPV6_FW_F_DRNG))
continue;
break;
}
case IPPROTO_ICMPV6:
{
struct icmp6_hdr *icmp;
if (offset != 0) /* Type isn't valid */
break;
PULLUP_TO(off + 2);
icmp = (struct icmp6_hdr *) ((caddr_t)ip6 + off);
if (!icmp6type_match(icmp, f))
continue;
break;
}
#undef PULLUP_TO
bogusfrag:
if (fw6_verbose)
ip6fw_report(NULL, ip6, rif, oif, off, nxt);
goto dropit;
}
got_match:
#ifndef IP6FW_DIVERT_RESTART
/* Ignore divert/tee rule if socket port is "ignport" */
switch (f->fw_flg & IPV6_FW_F_COMMAND) {
case IPV6_FW_F_DIVERT:
case IPV6_FW_F_TEE:
if (f->fw_divert_port == ignport)
continue; /* ignore this rule */
break;
}
#endif /* IP6FW_DIVERT_RESTART */
/* Update statistics */
f->fw_pcnt += 1;
f->fw_bcnt += ntohs(ip6->ip6_plen);
#ifdef __FreeBSD__
f->timestamp = time_second;
#else
f->timestamp = time.tv_sec;
#endif
/* Log to console if desired */
if ((f->fw_flg & IPV6_FW_F_PRN) && fw6_verbose)
ip6fw_report(f, ip6, rif, oif, off, nxt);
/* Take appropriate action */
switch (f->fw_flg & IPV6_FW_F_COMMAND) {
case IPV6_FW_F_ACCEPT:
return (0);
case IPV6_FW_F_COUNT:
continue;
case IPV6_FW_F_DIVERT:
return (f->fw_divert_port);
case IPV6_FW_F_TEE:
/*
* XXX someday tee packet here, but beware that you
* can't use m_copym() or m_copypacket() because
* the divert input routine modifies the mbuf
* (and these routines only increment reference
* counts in the case of mbuf clusters), so need
* to write custom routine.
*/
continue;
case IPV6_FW_F_SKIPTO:
#ifdef DIAGNOSTIC
while (chain->chain.le_next
&& chain->chain.le_next->rule->fw_number
< f->fw_skipto_rule)
#else
while (chain->chain.le_next->rule->fw_number
< f->fw_skipto_rule)
#endif
chain = chain->chain.le_next;
continue;
}
/* Deny/reject this packet using this rule */
rule = f;
break;
}
#ifdef DIAGNOSTIC
/* Rule 65535 should always be there and should always match */
if (!chain)
panic("ip6_fw: chain");
#endif
/*
* At this point, we're going to drop the packet.
* Send a reject notice if all of the following are true:
*
* - The packet matched a reject rule
* - The packet is not an ICMP packet, or is an ICMP query packet
* - The packet is not a multicast or broadcast packet
*/
if ((rule->fw_flg & IPV6_FW_F_COMMAND) == IPV6_FW_F_REJECT
&& (nxt != IPPROTO_ICMPV6 || is_icmp6_query(ip6, off))
&& !((*m)->m_flags & (M_BCAST|M_MCAST))
&& !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
switch (rule->fw_reject_code) {
case IPV6_FW_REJECT_RST:
#if 1 /* not tested */
{
struct tcphdr *const tcp =
(struct tcphdr *) ((caddr_t)ip6 + off);
struct {
struct ip6_hdr ip6;
struct tcphdr th;
} ti;
tcp_seq ack, seq;
int flags;
if (offset != 0 || (tcp->th_flags & TH_RST))
break;
ti.ip6 = *ip6;
ti.th = *tcp;
ti.th.th_seq = ntohl(ti.th.th_seq);
ti.th.th_ack = ntohl(ti.th.th_ack);
ti.ip6.ip6_nxt = IPPROTO_TCP;
if (ti.th.th_flags & TH_ACK) {
ack = 0;
seq = ti.th.th_ack;
flags = TH_RST;
} else {
ack = ti.th.th_seq;
if (((*m)->m_flags & M_PKTHDR) != 0) {
ack += (*m)->m_pkthdr.len - off
- (ti.th.th_off << 2);
} else if (ip6->ip6_plen) {
ack += ntohs(ip6->ip6_plen) + sizeof(*ip6)
- off - (ti.th.th_off << 2);
} else {
m_freem(*m);
*m = 0;
break;
}
seq = 0;
flags = TH_RST|TH_ACK;
}
bcopy(&ti, ip6, sizeof(ti));
#ifdef __NetBSD__
tcp_respond(NULL, NULL, *m, (struct tcphdr *)(ip6 + 1),
ack, seq, flags);
#elif defined(__FreeBSD__)
tcp_respond(NULL, ip6, (struct tcphdr *)(ip6 + 1),
*m, ack, seq, flags);
#else
m_freem(*m);
#endif
*m = NULL;
break;
}
#endif
default: /* Send an ICMP unreachable using code */
if (oif)
(*m)->m_pkthdr.rcvif = oif;
icmp6_error(*m, ICMP6_DST_UNREACH,
rule->fw_reject_code, 0);
*m = NULL;
break;
}
}
dropit:
/*
* Finally, drop the packet.
*/
if (*m) {
m_freem(*m);
*m = NULL;
}
return (0);
}
struct mbuf *
ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
int srcrt)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct sockaddr_in6 *dst;
struct rtentry *rt;
int error, type = 0, code = 0;
boolean_t proxy = FALSE;
struct mbuf *mcopy = NULL;
struct ifnet *ifp, *origifp; /* maybe unnecessary */
u_int32_t inzone, outzone;
struct in6_addr src_in6, dst_in6;
#if IPSEC
struct secpolicy *sp = NULL;
#endif
struct timeval timenow;
unsigned int ifscope = IFSCOPE_NONE;
#if PF
struct pf_mtag *pf_mtag;
#endif /* PF */
getmicrotime(&timenow);
#if PF
pf_mtag = pf_find_mtag(m);
if (pf_mtag != NULL && pf_mtag->pftag_rtableid != IFSCOPE_NONE)
ifscope = pf_mtag->pftag_rtableid;
/*
* If the caller provides a route which is on a different interface
* than the one specified for scoped forwarding, discard the route
* and do a lookup below.
*/
if (ifscope != IFSCOPE_NONE && (rt = ip6forward_rt->ro_rt) != NULL) {
RT_LOCK(rt);
if (rt->rt_ifp->if_index != ifscope) {
RT_UNLOCK(rt);
rtfree(rt);
rt = ip6forward_rt->ro_rt = NULL;
} else {
RT_UNLOCK(rt);
}
}
#endif /* PF */
#if IPSEC
/*
* Check AH/ESP integrity.
*/
/*
* Don't increment ip6s_cantforward because this is the check
* before forwarding packet actually.
*/
if (ipsec_bypass == 0) {
if (ipsec6_in_reject(m, NULL)) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_polvio);
m_freem(m);
return (NULL);
}
}
#endif /*IPSEC*/
/*
* Do not forward packets to multicast destination (should be handled
* by ip6_mforward().
* Do not forward packets with unspecified source. It was discussed
* in July 2000, on ipngwg mailing list.
*/
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++;
/* XXX 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 "
"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 (NULL);
}
if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
return (NULL);
}
/*
* See if the destination is a proxied address, and if so pretend
* that it's for us. This is mostly to handle NUD probes against
* the proxied addresses. We filter for ICMPv6 here and will let
* icmp6_input handle the rest.
*/
if (!srcrt && nd6_prproxy) {
VERIFY(!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst));
proxy = nd6_prproxy_isours(m, ip6, ip6forward_rt, ifscope);
/*
* Don't update hop limit while proxying; RFC 4389 4.1.
* Also skip IPsec forwarding path processing as this
* packet is not to be forwarded.
*/
if (proxy)
goto skip_ipsec;
}
ip6->ip6_hlim -= IPV6_HLIMDEC;
/*
* Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU -
* size of IPv6 + ICMPv6 headers) bytes of the packet in case
* we need to generate an ICMP6 message to the src.
* Thanks to M_EXT, in most cases copy will not occur.
*
* It is important to save it before IPsec processing as IPsec
* processing may modify the mbuf.
*/
mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
#if IPSEC
if (ipsec_bypass != 0)
goto skip_ipsec;
/* get a security policy for this packet */
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
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return (NULL);
}
error = 0;
/* check policy */
switch (sp->policy) {
case IPSEC_POLICY_DISCARD:
case IPSEC_POLICY_GENERATE:
/*
* This packet is just discarded.
*/
IPSEC_STAT_INCREMENT(ipsec6stat.out_polvio);
ip6stat.ip6s_cantforward++;
key_freesp(sp, KEY_SADB_UNLOCKED);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return (NULL);
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
/* no need to do IPsec. */
key_freesp(sp, KEY_SADB_UNLOCKED);
goto skip_ipsec;
case IPSEC_POLICY_IPSEC:
if (sp->req == NULL) {
/* XXX should be panic ? */
printf("ip6_forward: No IPsec request specified.\n");
ip6stat.ip6s_cantforward++;
key_freesp(sp, KEY_SADB_UNLOCKED);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return (NULL);
}
/* do IPsec */
break;
case IPSEC_POLICY_ENTRUST:
default:
/* should be panic ?? */
printf("ip6_forward: Invalid policy found. %d\n", sp->policy);
key_freesp(sp, KEY_SADB_UNLOCKED);
goto skip_ipsec;
}
{
struct ipsec_output_state state;
/*
* All the extension headers will become inaccessible
* (since they can be encrypted).
* Don't panic, we need no more updates to extension headers
* on inner IPv6 packet (since they are now encapsulated).
*
* IPv6 [ESP|AH] IPv6 [extension headers] payload
*/
bzero(&state, sizeof(state));
state.m = m;
state.dst = NULL; /* update at ipsec6_output_tunnel() */
error = ipsec6_output_tunnel(&state, sp, 0);
key_freesp(sp, KEY_SADB_UNLOCKED);
if (state.tunneled == 4)
return (NULL); /* packet is gone - sent over IPv4 */
m = state.m;
if (state.ro.ro_rt) {
rtfree(state.ro.ro_rt);
state.ro.ro_rt = NULL;
}
if (error) {
/* mbuf is already reclaimed in ipsec6_output_tunnel. */
switch (error) {
case EHOSTUNREACH:
case ENETUNREACH:
case EMSGSIZE:
case ENOBUFS:
case ENOMEM:
break;
default:
printf("ip6_output (ipsec): error code %d\n", error);
/* fall through */
case ENOENT:
/* don't show these error codes to the user */
break;
}
ip6stat.ip6s_cantforward++;
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return (NULL);
}
}
skip_ipsec:
#endif /* IPSEC */
dst = (struct sockaddr_in6 *)&ip6forward_rt->ro_dst;
if ((rt = ip6forward_rt->ro_rt) != NULL) {
RT_LOCK(rt);
/* Take an extra ref for ourselves */
RT_ADDREF_LOCKED(rt);
}
if (!srcrt) {
/*
* ip6forward_rt->ro_dst.sin6_addr is equal to ip6->ip6_dst
*/
if (rt == NULL || !(rt->rt_flags & RTF_UP) ||
rt->generation_id != route_generation) {
if (rt != NULL) {
/* Release extra ref */
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
rtfree(rt);
ip6forward_rt->ro_rt = NULL;
}
/* this probably fails but give it a try again */
rtalloc_scoped_ign((struct route *)ip6forward_rt,
RTF_PRCLONING, ifscope);
if ((rt = ip6forward_rt->ro_rt) != NULL) {
RT_LOCK(rt);
/* Take an extra ref for ourselves */
RT_ADDREF_LOCKED(rt);
}
}
if (rt == NULL) {
ip6stat.ip6s_noroute++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
m_freem(m);
return (NULL);
}
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) {
/* Release extra ref */
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_scoped_ign((struct route *)ip6forward_rt,
RTF_PRCLONING, ifscope);
if ((rt = ip6forward_rt->ro_rt) == NULL) {
ip6stat.ip6s_noroute++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
m_freem(m);
return (NULL);
}
RT_LOCK(rt);
/* Take an extra ref for ourselves */
RT_ADDREF_LOCKED(rt);
}
/*
* Source scope check: if a packet can't be delivered to its
* destination for the reason that the destination is beyond the scope
* of the source address, discard the packet and return an icmp6
* destination unreachable error with Code 2 (beyond scope of source
* address) unless we are proxying (source address is link local
* for NUDs.) We use a local copy of ip6_src, since in6_setscope()
* will possibly modify its first argument.
* [draft-ietf-ipngwg-icmp-v3-04.txt, Section 3.1]
*/
src_in6 = ip6->ip6_src;
if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) {
/* XXX: this should not happen */
ip6stat.ip6s_cantforward++;
ip6stat.ip6s_badscope++;
m_freem(m);
return (NULL);
}
if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) {
ip6stat.ip6s_cantforward++;
ip6stat.ip6s_badscope++;
m_freem(m);
return (NULL);
}
if (inzone != outzone && !proxy) {
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));
}
/* Release extra ref */
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
}
m_freem(m);
return (NULL);
}
/*
* Destination scope check: if a packet is going to break the scope
* zone of packet's destination address, discard it. This case should
* usually be prevented by appropriately-configured routing table, but
* we need an explicit check because we may mistakenly forward the
* packet to a different zone by (e.g.) a default route.
*/
dst_in6 = ip6->ip6_dst;
if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 ||
in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 ||
inzone != outzone) {
ip6stat.ip6s_cantforward++;
ip6stat.ip6s_badscope++;
m_freem(m);
return (NULL);
}
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
/*
* When we do IPsec tunnel ingress, we need to play
* with the link value (decrement IPsec header size
* from mtu value). The code is much simpler than v4
* case, as we have the outgoing interface for
* encapsulated packet as "rt->rt_ifp".
*/
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 becomes less than minimum MTU,
* tell minimum MTU (and I'll need to fragment it).
*/
if (mtu < IPV6_MMTU)
mtu = IPV6_MMTU;
#endif
/* Release extra ref */
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
} else {
/* Release extra ref */
RT_REMREF_LOCKED(rt);
RT_UNLOCK(rt);
}
m_freem(m);
return (NULL);
}
if (rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in6 *)(void *)rt->rt_gateway;
/*
* If we are to forward the packet using the same interface
* as one we got the packet from, perhaps we should send a redirect
* to sender to shortcut a hop.
* Only send redirect if source is sending directly to us,
* and if packet was not source routed (or has any options).
* Also, don't send redirect if forwarding using a route
* modified by a redirect.
*/
if (!proxy &&
ip6_sendredirects && 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) {
/*
* If the incoming interface is equal to the outgoing
* one, and the link attached to the interface is
* point-to-point, then it will be highly probable
* that a routing loop occurs. Thus, we immediately
* drop the packet and send an ICMPv6 error message.
*
* type/code is based on suggestion by Rich Draves.
* not sure if it is the best pick.
*/
RT_REMREF_LOCKED(rt); /* Release extra ref */
RT_UNLOCK(rt);
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADDR, 0);
m_freem(m);
return (NULL);
}
type = ND_REDIRECT;
}
#if IPFW2
/*
* Check with the firewall...
*/
if (ip6_fw_enable && ip6_fw_chk_ptr) {
u_short port = 0;
ifp = rt->rt_ifp;
/* Drop the lock but retain the extra ref */
RT_UNLOCK(rt);
/* If ipfw says divert, we have to just drop packet */
if (ip6_fw_chk_ptr(&ip6, ifp, &port, &m)) {
m_freem(m);
goto freecopy;
}
if (!m) {
goto freecopy;
}
/* We still have the extra ref on rt */
RT_LOCK(rt);
}
#endif
/*
* Fake scoped addresses. Note that even link-local source or
* destinaion can appear, if the originating node just sends the
* packet to us (without address resolution for the destination).
* Since both icmp6_error and icmp6_redirect_output fill the embedded
* link identifiers, we can do this stuff after making a copy for
* returning an error.
*/
if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
/*
* See corresponding comments in ip6_output.
* XXX: but is it possible that ip6_forward() sends a packet
* to a loopback interface? I don't think so, and thus
* I bark here. ([email protected])
* XXX: it is common to route invalid packets to loopback.
* also, the codepath will be visited on use of ::1 in
* rthdr. (itojun)
*/
#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));
}
/* we can just use rcvif in forwarding. */
origifp = m->m_pkthdr.rcvif;
}
else
origifp = rt->rt_ifp;
/*
* clear embedded scope identifiers if necessary.
* in6_clearscope will touch the addresses only when necessary.
*/
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
ifp = rt->rt_ifp;
/* Drop the lock but retain the extra ref */
RT_UNLOCK(rt);
/*
* If this is to be processed locally, let ip6_input have it.
*/
if (proxy) {
VERIFY(m->m_pkthdr.aux_flags & MAUXF_PROXY_DST);
/* Release extra ref */
RT_REMREF(rt);
if (mcopy != NULL)
m_freem(mcopy);
return (m);
}
#if PF
/* Invoke outbound packet filter */
error = pf_af_hook(ifp, NULL, &m, AF_INET6, FALSE, NULL);
if (error != 0 || m == NULL) {
if (m != NULL) {
panic("%s: unexpected packet %p\n", __func__, m);
/* NOTREACHED */
}
/* Already freed by callee */
goto senderr;
}
ip6 = mtod(m, struct ip6_hdr *);
#endif /* PF */
error = nd6_output(ifp, origifp, m, dst, rt, NULL);
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 /* PF */
if (mcopy == NULL) {
/* Release extra ref */
RT_REMREF(rt);
return (NULL);
}
switch (error) {
case 0:
#if 1
if (type == ND_REDIRECT) {
icmp6_redirect_output(mcopy, rt);
/* Release extra ref */
RT_REMREF(rt);
return (NULL);
}
#endif
goto freecopy;
case EMSGSIZE:
/* xxx MTU is constant in PPP? */
goto freecopy;
case ENOBUFS:
/* Tell source to slow down like source quench in IP? */
goto freecopy;
case ENETUNREACH: /* shouldn't happen, checked above */
case EHOSTUNREACH:
case ENETDOWN:
case EHOSTDOWN:
default:
type = ICMP6_DST_UNREACH;
code = ICMP6_DST_UNREACH_ADDR;
break;
}
icmp6_error(mcopy, type, code, 0);
/* Release extra ref */
RT_REMREF(rt);
return (NULL);
freecopy:
m_freem(mcopy);
/* Release extra ref */
RT_REMREF(rt);
return (NULL);
}
/*
* Fragment input
* NOTE: this function is called with the inet6_domain_mutex held from ip6_input.
* inet6_domain_mutex is protecting he frag6 queue manipulation.
*/
int
frag6_input(struct mbuf **mp, int *offp, int proto)
{
#pragma unused(proto)
struct mbuf *m = *mp, *t;
struct ip6_hdr *ip6;
struct ip6_frag *ip6f;
struct ip6q *q6;
struct ip6asfrag *af6, *ip6af, *af6dwn;
int offset = *offp, nxt, i, next;
int first_frag = 0;
int fragoff, frgpartlen; /* must be larger than u_int16_t */
struct ifnet *dstifp;
struct ifaddr *ifa = NULL;
u_int8_t ecn, ecn0;
#ifdef IN6_IFSTAT_STRICT
struct route_in6 ro;
struct sockaddr_in6 *dst;
#endif
/* Expect 32-bit aligned data pointer on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
ip6 = mtod(m, struct ip6_hdr *);
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, offset, sizeof(struct ip6_frag), return IPPROTO_DONE);
ip6f = (struct ip6_frag *)((caddr_t)ip6 + offset);
#else
IP6_EXTHDR_GET(ip6f, struct ip6_frag *, m, offset, sizeof(*ip6f));
if (ip6f == NULL)
return IPPROTO_DONE;
#endif
dstifp = NULL;
#ifdef IN6_IFSTAT_STRICT
/* find the destination interface of the packet. */
bzero(&ro, sizeof (ro));
dst = (struct sockaddr_in6 *)&ro.ro_dst;
dst->sin6_family = AF_INET6;
dst->sin6_len = sizeof (struct sockaddr_in6);
dst->sin6_addr = ip6->ip6_dst;
rtalloc((struct route *)&ro);
if (ro.ro_rt != NULL) {
RT_LOCK(ro.ro_rt);
if ((ifa = ro.ro_rt->rt_ifa) != NULL) {
IFA_ADDREF(ifa);
dstifp = ((struct in6_ifaddr *)ro.ro_rt->rt_ifa)->ia_ifp;
}
RT_UNLOCK(ro.ro_rt);
rtfree(ro.ro_rt);
ro.ro_rt = NULL;
}
#else
/* we are violating the spec, this is not the destination interface */
if ((m->m_flags & M_PKTHDR) != 0)
dstifp = m->m_pkthdr.rcvif;
#endif
/* jumbo payload can't contain a fragment header */
if (ip6->ip6_plen == 0) {
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, offset);
in6_ifstat_inc(dstifp, ifs6_reass_fail);
if (ifa != NULL)
IFA_REMREF(ifa);
return IPPROTO_DONE;
}
/*
* check whether fragment packet's fragment length is
* multiple of 8 octets.
* sizeof(struct ip6_frag) == 8
* sizeof(struct ip6_hdr) = 40
*/
if ((ip6f->ip6f_offlg & IP6F_MORE_FRAG) &&
(((ntohs(ip6->ip6_plen) - offset) & 0x7) != 0)) {
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
offsetof(struct ip6_hdr, ip6_plen));
in6_ifstat_inc(dstifp, ifs6_reass_fail);
if (ifa != NULL)
IFA_REMREF(ifa);
return IPPROTO_DONE;
}
ip6stat.ip6s_fragments++;
in6_ifstat_inc(dstifp, ifs6_reass_reqd);
/* offset now points to data portion */
offset += sizeof(struct ip6_frag);
frag6_doing_reass = 1;
/*
* Enforce upper bound on number of fragments.
* If maxfrag is 0, never accept fragments.
* If maxfrag is -1, accept all fragments without limitation.
*/
if (ip6_maxfrags < 0)
;
else if (frag6_nfrags >= (u_int)ip6_maxfrags)
goto dropfrag;
for (q6 = ip6q.ip6q_next; q6 != &ip6q; q6 = q6->ip6q_next)
if (ip6f->ip6f_ident == q6->ip6q_ident &&
IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, &q6->ip6q_src) &&
IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &q6->ip6q_dst))
break;
if (q6 == &ip6q) {
/*
* the first fragment to arrive, create a reassembly queue.
*/
first_frag = 1;
/*
* Enforce upper bound on number of fragmented packets
* for which we attempt reassembly;
* If maxfrag is 0, never accept fragments.
* If maxfrag is -1, accept all fragments without limitation.
*/
if (ip6_maxfragpackets < 0)
;
else if (frag6_nfragpackets >= (u_int)ip6_maxfragpackets)
goto dropfrag;
frag6_nfragpackets++;
q6 = (struct ip6q *)_MALLOC(sizeof(struct ip6q), M_FTABLE,
M_DONTWAIT);
if (q6 == NULL)
goto dropfrag;
bzero(q6, sizeof(*q6));
frag6_insque(q6, &ip6q);
/* ip6q_nxt will be filled afterwards, from 1st fragment */
q6->ip6q_down = q6->ip6q_up = (struct ip6asfrag *)q6;
#ifdef notyet
q6->ip6q_nxtp = (u_char *)nxtp;
#endif
q6->ip6q_ident = ip6f->ip6f_ident;
q6->ip6q_ttl = IPV6_FRAGTTL;
q6->ip6q_src = ip6->ip6_src;
q6->ip6q_dst = ip6->ip6_dst;
q6->ip6q_ecn =
(ntohl(ip6->ip6_flow) >> 20) & IPTOS_ECN_MASK;
q6->ip6q_unfrglen = -1; /* The 1st fragment has not arrived. */
q6->ip6q_nfrag = 0;
}
void
ip6_forward(struct mbuf *m, int srcrt)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct sockaddr_in6 *dst;
struct rtentry *rt;
int error = 0, type = 0, code = 0;
struct mbuf *mcopy = NULL;
struct ifnet *origifp; /* maybe unnecessary */
#ifdef IPSEC
u_int8_t sproto = 0;
struct m_tag *mtag;
union sockaddr_union sdst;
struct tdb_ident *tdbi;
u_int32_t sspi;
struct tdb *tdb;
int s;
#if NPF > 0
struct ifnet *encif;
#endif
#endif /* IPSEC */
u_int rtableid = 0;
/*
* Do not forward packets to multicast destination (should be handled
* by ip6_mforward().
* Do not forward packets with unspecified source. It was discussed
* in July 2000, on ipngwg mailing list.
*/
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++;
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
if (ip6_log_time + ip6_log_interval < time_second) {
ip6_log_time = time_second;
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,
m->m_pkthdr.rcvif->if_xname);
}
m_freem(m);
return;
}
if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
return;
}
ip6->ip6_hlim -= IPV6_HLIMDEC;
#if NPF > 0
reroute:
#endif
#ifdef IPSEC
if (!ipsec_in_use)
goto done_spd;
s = splnet();
/*
* Check if there was an outgoing SA bound to the flow
* from a transport protocol.
*/
/* Do we have any pending SAs to apply ? */
mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
if (mtag != NULL) {
#ifdef DIAGNOSTIC
if (mtag->m_tag_len != sizeof (struct tdb_ident))
panic("ip6_forward: tag of length %d (should be %d",
mtag->m_tag_len, sizeof (struct tdb_ident));
#endif
tdbi = (struct tdb_ident *)(mtag + 1);
tdb = gettdb(tdbi->rdomain, tdbi->spi, &tdbi->dst,
tdbi->proto);
if (tdb == NULL)
error = -EINVAL;
m_tag_delete(m, mtag);
} else
tdb = ipsp_spd_lookup(m, AF_INET6, sizeof(struct ip6_hdr),
&error, IPSP_DIRECTION_OUT, NULL, NULL);
if (tdb == NULL) {
splx(s);
if (error == 0) {
/*
* No IPsec processing required, we'll just send the
* packet out.
*/
sproto = 0;
/* Fall through to routing/multicast handling */
} else {
/*
* -EINVAL is used to indicate that the packet should
* be silently dropped, typically because we've asked
* key management for an SA.
*/
if (error == -EINVAL) /* Should silently drop packet */
error = 0;
goto freecopy;
}
} else {
/* Loop detection */
for (mtag = m_tag_first(m); mtag != NULL;
mtag = m_tag_next(m, mtag)) {
if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
mtag->m_tag_id !=
PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
continue;
tdbi = (struct tdb_ident *)(mtag + 1);
if (tdbi->spi == tdb->tdb_spi &&
tdbi->proto == tdb->tdb_sproto &&
tdbi->rdomain == tdb->tdb_rdomain &&
!bcmp(&tdbi->dst, &tdb->tdb_dst,
sizeof(union sockaddr_union))) {
splx(s);
sproto = 0; /* mark as no-IPsec-needed */
goto done_spd;
}
}
/* We need to do IPsec */
bcopy(&tdb->tdb_dst, &sdst, sizeof(sdst));
sspi = tdb->tdb_spi;
sproto = tdb->tdb_sproto;
splx(s);
}
/* Fall through to the routing/multicast handling code */
done_spd:
#endif /* IPSEC */
#if NPF > 0
rtableid = m->m_pkthdr.rdomain;
#endif
/*
* Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU -
* size of IPv6 + ICMPv6 headers) bytes of the packet in case
* we need to generate an ICMP6 message to the src.
* Thanks to M_EXT, in most cases copy will not occur.
*
* It is important to save it before IPsec processing as IPsec
* processing may modify the mbuf.
*/
mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
dst = &ip6_forward_rt.ro_dst;
if (!srcrt) {
/*
* ip6_forward_rt.ro_dst.sin6_addr is equal to ip6->ip6_dst
*/
if (ip6_forward_rt.ro_rt == 0 ||
(ip6_forward_rt.ro_rt->rt_flags & RTF_UP) == 0 ||
ip6_forward_rt.ro_tableid != rtableid) {
if (ip6_forward_rt.ro_rt) {
RTFREE(ip6_forward_rt.ro_rt);
ip6_forward_rt.ro_rt = 0;
}
/* this probably fails but give it a try again */
ip6_forward_rt.ro_tableid = rtableid;
rtalloc_mpath((struct route *)&ip6_forward_rt,
&ip6->ip6_src.s6_addr32[0]);
}
if (ip6_forward_rt.ro_rt == 0) {
ip6stat.ip6s_noroute++;
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
m_freem(m);
return;
}
} else if (ip6_forward_rt.ro_rt == 0 ||
(ip6_forward_rt.ro_rt->rt_flags & RTF_UP) == 0 ||
!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr) ||
ip6_forward_rt.ro_tableid != rtableid) {
if (ip6_forward_rt.ro_rt) {
RTFREE(ip6_forward_rt.ro_rt);
ip6_forward_rt.ro_rt = 0;
}
bzero(dst, sizeof(*dst));
dst->sin6_len = sizeof(struct sockaddr_in6);
dst->sin6_family = AF_INET6;
dst->sin6_addr = ip6->ip6_dst;
ip6_forward_rt.ro_tableid = rtableid;
rtalloc_mpath((struct route *)&ip6_forward_rt,
&ip6->ip6_src.s6_addr32[0]);
if (ip6_forward_rt.ro_rt == 0) {
ip6stat.ip6s_noroute++;
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
m_freem(m);
return;
}
}
rt = ip6_forward_rt.ro_rt;
/*
* Scope check: if a packet can't be delivered to its destination
* for the reason that the destination is beyond the scope of the
* source address, discard the packet and return an icmp6 destination
* unreachable error with Code 2 (beyond scope of source address).
* [draft-ietf-ipngwg-icmp-v3-00.txt, Section 3.1]
*/
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 < time_second) {
ip6_log_time = time_second;
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,
m->m_pkthdr.rcvif->if_xname, rt->rt_ifp->if_xname);
}
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
m_freem(m);
goto freert;
}
#ifdef IPSEC
/*
* Check if the packet needs encapsulation.
* ipsp_process_packet will never come back to here.
* XXX ipsp_process_packet() calls ip6_output(), and there'll be no
* PMTU notification. is it okay?
*/
if (sproto != 0) {
s = splnet();
tdb = gettdb(rtable_l2(m->m_pkthdr.rdomain),
sspi, &sdst, sproto);
if (tdb == NULL) {
splx(s);
error = EHOSTUNREACH;
m_freem(m);
goto senderr; /*XXX*/
}
#if NPF > 0
if ((encif = enc_getif(tdb->tdb_rdomain,
tdb->tdb_tap)) == NULL ||
pf_test6(PF_FWD, encif, &m, NULL) != PF_PASS) {
splx(s);
error = EHOSTUNREACH;
m_freem(m);
goto senderr;
}
if (m == NULL) {
splx(s);
goto senderr;
}
ip6 = mtod(m, struct ip6_hdr *);
/*
* PF_TAG_REROUTE handling or not...
* Packet is entering IPsec so the routing is
* already overruled by the IPsec policy.
* Until now the change was not reconsidered.
* What's the behaviour?
*/
#endif
m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
/* Callee frees mbuf */
error = ipsp_process_packet(m, tdb, AF_INET6, 0);
splx(s);
m_freem(mcopy);
goto freert;
}
int
route6_input(struct mbuf **mp, int *offp, int proto)
{
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) {
IP6_STATINC(IP6_STAT_TOOSHORT);
return IPPROTO_DONE;
}
switch (rh->ip6r_type) {
#if 0
/*
* See http://www.secdev.org/conf/IPv6_RH_security-csw07.pdf
* for why IPV6_RTHDR_TYPE_0 is banned here.
*
* We return ICMPv6 parameter problem so that innocent people
* (not an attacker) would notice about the use of IPV6_RTHDR_TYPE_0.
* Since there's no amplification, and ICMPv6 error will be rate-
* controlled, it shouldn't cause any problem.
* If you are concerned about this, you may want to use the following
* code fragment:
*
* case IPV6_RTHDR_TYPE_0:
* m_freem(m);
* return (IPPROTO_DONE);
*/
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) {
IP6_STATINC(IP6_STAT_TOOSHORT);
return IPPROTO_DONE;
}
if (ip6_rthdr0(m, ip6, (struct ip6_rthdr0 *)rh))
return (IPPROTO_DONE);
break;
#endif
default:
/* unknown routing type */
if (rh->ip6r_segleft == 0) {
rhlen = (rh->ip6r_len + 1) << 3;
break; /* Final dst. Just ignore the header. */
}
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
(char *)&rh->ip6r_type - (char *)ip6);
return (IPPROTO_DONE);
}
*offp += rhlen;
return (rh->ip6r_nxt);
}
/*
* Forward a packet. If some error occurs return the sender
* an icmp packet. Note we can't always generate a meaningful
* icmp message because icmp doesn't have a large enough repertoire
* of codes and types.
*
* If not forwarding, just drop the packet. This could be confusing
* if ipforwarding was zero but some routing protocol was advancing
* us as a gateway to somewhere. However, we must let the routing
* protocol deal with that.
*
*/
void
ip6_forward(struct mbuf *m, int srcrt)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct sockaddr_in6 *dst = NULL;
struct rtentry *rt = NULL;
struct route_in6 rin6;
int error, type = 0, code = 0;
struct mbuf *mcopy = NULL;
struct ifnet *origifp; /* maybe unnecessary */
u_int32_t inzone, outzone;
struct in6_addr src_in6, dst_in6, odst;
struct m_tag *fwd_tag;
char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
/*
* Do not forward packets to multicast destination (should be handled
* by ip6_mforward().
* Do not forward packets with unspecified source. It was discussed
* in July 2000, on the ipngwg mailing list.
*/
if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 ||
IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
IP6STAT_INC(ip6s_cantforward);
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
if (V_ip6_log_time + V_ip6_log_interval < time_uptime) {
V_ip6_log_time = time_uptime;
log(LOG_DEBUG,
"cannot forward "
"from %s to %s nxt %d received on %s\n",
ip6_sprintf(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst),
ip6->ip6_nxt,
if_name(m->m_pkthdr.rcvif));
}
m_freem(m);
return;
}
if (
#ifdef IPSTEALTH
V_ip6stealth == 0 &&
#endif
ip6->ip6_hlim <= IPV6_HLIMDEC) {
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
return;
}
/*
* Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU -
* size of IPv6 + ICMPv6 headers) bytes of the packet in case
* we need to generate an ICMP6 message to the src.
* Thanks to M_EXT, in most cases copy will not occur.
*
* It is important to save it before IPsec processing as IPsec
* processing may modify the mbuf.
*/
mcopy = m_copym(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN),
M_NOWAIT);
#ifdef IPSTEALTH
if (V_ip6stealth == 0)
#endif
ip6->ip6_hlim -= IPV6_HLIMDEC;
#if defined(IPSEC) || defined(IPSEC_SUPPORT)
if (IPSEC_ENABLED(ipv6)) {
if ((error = IPSEC_FORWARD(ipv6, m)) != 0) {
/* mbuf consumed by IPsec */
m_freem(mcopy);
if (error != EINPROGRESS)
IP6STAT_INC(ip6s_cantforward);
return;
}
/* No IPsec processing required */
}
#endif
again:
bzero(&rin6, sizeof(struct route_in6));
dst = (struct sockaddr_in6 *)&rin6.ro_dst;
dst->sin6_len = sizeof(struct sockaddr_in6);
dst->sin6_family = AF_INET6;
dst->sin6_addr = ip6->ip6_dst;
again2:
rin6.ro_rt = in6_rtalloc1((struct sockaddr *)dst, 0, 0, M_GETFIB(m));
rt = rin6.ro_rt;
if (rin6.ro_rt != NULL)
RT_UNLOCK(rin6.ro_rt);
else {
IP6STAT_INC(ip6s_noroute);
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
goto bad;
}
/*
* Source scope check: if a packet can't be delivered to its
* destination for the reason that the destination is beyond the scope
* of the source address, discard the packet and return an icmp6
* destination unreachable error with Code 2 (beyond scope of source
* address). We use a local copy of ip6_src, since in6_setscope()
* will possibly modify its first argument.
* [draft-ietf-ipngwg-icmp-v3-04.txt, Section 3.1]
*/
src_in6 = ip6->ip6_src;
if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) {
/* XXX: this should not happen */
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
goto bad;
}
if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) {
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
goto bad;
}
if (inzone != outzone) {
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard);
if (V_ip6_log_time + V_ip6_log_interval < time_uptime) {
V_ip6_log_time = time_uptime;
log(LOG_DEBUG,
"cannot forward "
"src %s, dst %s, nxt %d, rcvif %s, outif %s\n",
ip6_sprintf(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst),
ip6->ip6_nxt,
if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp));
}
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
goto bad;
}
/*
* Destination scope check: if a packet is going to break the scope
* zone of packet's destination address, discard it. This case should
* usually be prevented by appropriately-configured routing table, but
* we need an explicit check because we may mistakenly forward the
* packet to a different zone by (e.g.) a default route.
*/
dst_in6 = ip6->ip6_dst;
if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 ||
in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 ||
inzone != outzone) {
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
goto bad;
}
if (rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in6 *)rt->rt_gateway;
/*
* If we are to forward the packet using the same interface
* as one we got the packet from, perhaps we should send a redirect
* to sender to shortcut a hop.
* Only send redirect if source is sending directly to us,
* and if packet was not source routed (or has any options).
* Also, don't send redirect if forwarding using a route
* modified by a redirect.
*/
if (V_ip6_sendredirects && 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) {
/*
* If the incoming interface is equal to the outgoing
* one, and the link attached to the interface is
* point-to-point, then it will be highly probable
* that a routing loop occurs. Thus, we immediately
* drop the packet and send an ICMPv6 error message.
*
* type/code is based on suggestion by Rich Draves.
* not sure if it is the best pick.
*/
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADDR, 0);
goto bad;
}
type = ND_REDIRECT;
}
/*
* Fake scoped addresses. Note that even link-local source or
* destinaion can appear, if the originating node just sends the
* packet to us (without address resolution for the destination).
* Since both icmp6_error and icmp6_redirect_output fill the embedded
* link identifiers, we can do this stuff after making a copy for
* returning an error.
*/
if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
/*
* See corresponding comments in ip6_output.
* XXX: but is it possible that ip6_forward() sends a packet
* to a loopback interface? I don't think so, and thus
* I bark here. ([email protected])
* XXX: it is common to route invalid packets to loopback.
* also, the codepath will be visited on use of ::1 in
* rthdr. (itojun)
*/
#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(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst),
ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif),
if_name(rt->rt_ifp));
}
/* we can just use rcvif in forwarding. */
origifp = m->m_pkthdr.rcvif;
}
else
origifp = rt->rt_ifp;
/*
* clear embedded scope identifiers if necessary.
* in6_clearscope will touch the addresses only when necessary.
*/
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
/* Jump over all PFIL processing if hooks are not active. */
if (!PFIL_HOOKED(&V_inet6_pfil_hook))
goto pass;
odst = ip6->ip6_dst;
/* Run through list of hooks for output packets. */
error = pfil_run_hooks(&V_inet6_pfil_hook, &m, rt->rt_ifp, PFIL_OUT, NULL);
if (error != 0 || m == NULL)
goto freecopy; /* consumed by filter */
ip6 = mtod(m, struct ip6_hdr *);
/* See if destination IP address was changed by packet filter. */
if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
m->m_flags |= M_SKIP_FIREWALL;
/* If destination is now ourself drop to ip6_input(). */
if (in6_localip(&ip6->ip6_dst))
m->m_flags |= M_FASTFWD_OURS;
else {
RTFREE(rt);
goto again; /* Redo the routing table lookup. */
}
}
/* See if local, if yes, send it to netisr. */
if (m->m_flags & M_FASTFWD_OURS) {
if (m->m_pkthdr.rcvif == NULL)
m->m_pkthdr.rcvif = V_loif;
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
m->m_pkthdr.csum_flags |=
CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xffff;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
#endif
error = netisr_queue(NETISR_IPV6, m);
goto out;
}
/* Or forward to some other address? */
if ((m->m_flags & M_IP6_NEXTHOP) &&
(fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
dst = (struct sockaddr_in6 *)&rin6.ro_dst;
bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in6));
m->m_flags |= M_SKIP_FIREWALL;
m->m_flags &= ~M_IP6_NEXTHOP;
m_tag_delete(m, fwd_tag);
RTFREE(rt);
goto again2;
}
pass:
/* See if the size was changed by the packet filter. */
if (m->m_pkthdr.len > IN6_LINKMTU(rt->rt_ifp)) {
in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig);
if (mcopy)
icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0,
IN6_LINKMTU(rt->rt_ifp));
goto bad;
}
error = nd6_output_ifp(rt->rt_ifp, origifp, m, dst, NULL);
if (error) {
in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard);
IP6STAT_INC(ip6s_cantforward);
} else {
IP6STAT_INC(ip6s_forward);
in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward);
if (type)
IP6STAT_INC(ip6s_redirectsent);
else {
if (mcopy)
goto freecopy;
}
}
if (mcopy == NULL)
goto out;
switch (error) {
case 0:
if (type == ND_REDIRECT) {
icmp6_redirect_output(mcopy, rt);
goto out;
}
goto freecopy;
case EMSGSIZE:
/* xxx MTU is constant in PPP? */
goto freecopy;
case ENOBUFS:
/* Tell source to slow down like source quench in IP? */
goto freecopy;
case ENETUNREACH: /* shouldn't happen, checked above */
case EHOSTUNREACH:
case ENETDOWN:
case EHOSTDOWN:
default:
type = ICMP6_DST_UNREACH;
code = ICMP6_DST_UNREACH_ADDR;
break;
}
icmp6_error(mcopy, type, code, 0);
goto out;
freecopy:
m_freem(mcopy);
goto out;
bad:
m_freem(m);
out:
if (rt != NULL)
RTFREE(rt);
}
void
ip6_forward(struct mbuf *m, int srcrt)
{
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 *origifp; /* maybe unnecessary */
#ifdef IPSEC
struct secpolicy *sp = NULL;
#endif
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
/*
* Don't increment ip6s_cantforward because this is the check
* before forwarding packet actually.
*/
if (ipsec6_in_reject(m, NULL)) {
#if !defined(FAST_IPSEC)
ipsec6stat.in_polvio++;
#endif
m_freem(m);
return;
}
#endif /* IPSEC */
/*
* Do not forward packets to multicast destination (should be handled
* by ip6_mforward().
* Do not forward packets with unspecified source. It was discussed
* in July 2000, on ipngwg mailing list.
*/
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++;
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
if (ip6_log_time + ip6_log_interval < time_second) {
ip6_log_time = time_second;
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) {
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
return;
}
ip6->ip6_hlim -= IPV6_HLIMDEC;
/*
* Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU -
* size of IPv6 + ICMPv6 headers) bytes of the packet in case
* we need to generate an ICMP6 message to the src.
* Thanks to M_EXT, in most cases copy will not occur.
*
* It is important to save it before IPsec processing as IPsec
* processing may modify the mbuf.
*/
mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
#ifdef IPSEC
/* get a security policy for this packet */
sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, IP_FORWARDING,
&error);
if (sp == NULL) {
ipsec6stat.out_inval++;
ip6stat.ip6s_cantforward++;
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
error = 0;
/* check policy */
switch (sp->policy) {
case IPSEC_POLICY_DISCARD:
/*
* This packet is just discarded.
*/
ipsec6stat.out_polvio++;
ip6stat.ip6s_cantforward++;
key_freesp(sp);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
/* no need to do IPsec. */
key_freesp(sp);
goto skip_ipsec;
case IPSEC_POLICY_IPSEC:
if (sp->req == NULL) {
/* XXX should be panic ? */
kprintf("ip6_forward: No IPsec request specified.\n");
ip6stat.ip6s_cantforward++;
key_freesp(sp);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
/* do IPsec */
break;
case IPSEC_POLICY_ENTRUST:
default:
/* should be panic ?? */
kprintf("ip6_forward: Invalid policy found. %d\n", sp->policy);
key_freesp(sp);
goto skip_ipsec;
}
{
struct ipsec_output_state state;
/*
* All the extension headers will become inaccessible
* (since they can be encrypted).
* Don't panic, we need no more updates to extension headers
* on inner IPv6 packet (since they are now encapsulated).
*
* IPv6 [ESP|AH] IPv6 [extension headers] payload
*/
bzero(&state, sizeof(state));
state.m = m;
state.ro = NULL; /* update at ipsec6_output_tunnel() */
state.dst = NULL; /* update at ipsec6_output_tunnel() */
error = ipsec6_output_tunnel(&state, sp, 0);
m = state.m;
key_freesp(sp);
if (error) {
/* mbuf is already reclaimed in ipsec6_output_tunnel. */
switch (error) {
case EHOSTUNREACH:
case ENETUNREACH:
case EMSGSIZE:
case ENOBUFS:
case ENOMEM:
break;
default:
kprintf("ip6_output (ipsec): error code %d\n", error);
/* fall through */
case ENOENT:
/* don't show these error codes to the user */
break;
}
ip6stat.ip6s_cantforward++;
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
}
skip_ipsec:
#endif /* IPSEC */
dst = (struct sockaddr_in6 *)&ip6_forward_rt.ro_dst;
if (!srcrt) {
/*
* ip6_forward_rt.ro_dst.sin6_addr is equal to ip6->ip6_dst
*/
if (ip6_forward_rt.ro_rt == NULL ||
!(ip6_forward_rt.ro_rt->rt_flags & RTF_UP)) {
if (ip6_forward_rt.ro_rt) {
RTFREE(ip6_forward_rt.ro_rt);
ip6_forward_rt.ro_rt = 0;
}
/* this probably fails but give it a try again */
rtalloc_ign((struct route *)&ip6_forward_rt,
RTF_PRCLONING);
}
if (ip6_forward_rt.ro_rt == NULL) {
ip6stat.ip6s_noroute++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
m_freem(m);
return;
}
} else if ((rt = ip6_forward_rt.ro_rt) == NULL ||
!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr)) {
if (ip6_forward_rt.ro_rt) {
RTFREE(ip6_forward_rt.ro_rt);
ip6_forward_rt.ro_rt = 0;
}
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 *)&ip6_forward_rt, RTF_PRCLONING);
if (ip6_forward_rt.ro_rt == NULL) {
ip6stat.ip6s_noroute++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
m_freem(m);
return;
}
}
rt = ip6_forward_rt.ro_rt;
/*
* Scope check: if a packet can't be delivered to its destination
* for the reason that the destination is beyond the scope of the
* source address, discard the packet and return an icmp6 destination
* unreachable error with Code 2 (beyond scope of source address).
* [draft-ietf-ipngwg-icmp-v3-02.txt, Section 3.1]
*/
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 < time_second) {
ip6_log_time = time_second;
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));
}
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
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) {
u_long mtu;
#ifdef IPSEC
struct secpolicy *sp;
int ipsecerror;
size_t ipsechdrsiz;
#endif
mtu = rt->rt_ifp->if_mtu;
#ifdef IPSEC
/*
* When we do IPsec tunnel ingress, we need to play
* with if_mtu value (decrement IPsec header size
* from mtu value). The code is much simpler than v4
* case, as we have the outgoing interface for
* encapsulated packet as "rt->rt_ifp".
*/
sp = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
IP_FORWARDING, &ipsecerror);
if (sp) {
ipsechdrsiz = ipsec6_hdrsiz(mcopy,
IPSEC_DIR_OUTBOUND, NULL);
if (ipsechdrsiz < mtu)
mtu -= ipsechdrsiz;
}
/*
* if mtu becomes less than minimum MTU,
* tell minimum MTU (and I'll need to fragment it).
*/
if (mtu < IPV6_MMTU)
mtu = IPV6_MMTU;
#endif
icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
}
m_freem(m);
return;
}
if (rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in6 *)rt->rt_gateway;
/*
* If we are to forward the packet using the same interface
* as one we got the packet from, perhaps we should send a redirect
* to sender to shortcut a hop.
* Only send redirect if source is sending directly to us,
* and if packet was not source routed (or has any options).
* Also, don't send redirect if forwarding using a route
* modified by a redirect.
*/
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) {
/*
* If the incoming interface is equal to the outgoing
* one, and the link attached to the interface is
* point-to-point, then it will be highly probable
* that a routing loop occurs. Thus, we immediately
* drop the packet and send an ICMPv6 error message.
*
* type/code is based on suggestion by Rich Draves.
* not sure if it is the best pick.
*/
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADDR, 0);
m_freem(m);
return;
}
type = ND_REDIRECT;
}
/*
* Check with the firewall...
*/
if (ip6_fw_enable && ip6_fw_chk_ptr) {
u_short port = 0;
/* If ipfw says divert, we have to just drop packet */
if ((*ip6_fw_chk_ptr)(&ip6, rt->rt_ifp, &port, &m)) {
m_freem(m);
goto freecopy;
}
if (!m)
goto freecopy;
}
/*
* Fake scoped addresses. Note that even link-local source or
* destinaion can appear, if the originating node just sends the
* packet to us (without address resolution for the destination).
* Since both icmp6_error and icmp6_redirect_output fill the embedded
* link identifiers, we can do this stuff after making a copy for
* returning an error.
*/
if (rt->rt_ifp->if_flags & IFF_LOOPBACK) {
/*
* See corresponding comments in ip6_output.
* XXX: but is it possible that ip6_forward() sends a packet
* to a loopback interface? I don't think so, and thus
* I bark here. ([email protected])
* XXX: it is common to route invalid packets to loopback.
* also, the codepath will be visited on use of ::1 in
* rthdr. (itojun)
*/
#if 1
if (0)
#else
if ((rt->rt_flags & (RTF_BLACKHOLE | RTF_REJECT)) == 0)
#endif
{
kprintf("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));
}
/* we can just use rcvif in forwarding. */
origifp = m->m_pkthdr.rcvif;
}
else
origifp = rt->rt_ifp;
/*
* clear embedded scope identifiers if necessary.
* in6_clearscope will touch the addresses only when necessary.
*/
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
/*
* Run through list of hooks for output packets.
*/
if (pfil_has_hooks(&inet6_pfil_hook)) {
error = pfil_run_hooks(&inet6_pfil_hook, &m, rt->rt_ifp,
PFIL_OUT);
if (error != 0)
goto senderr;
if (m == NULL)
goto freecopy;
ip6 = mtod(m, struct ip6_hdr *);
}
struct mbuf*
ip6_tryforward(struct mbuf *m)
{
struct sockaddr_in6 dst;
struct nhop6_basic nh;
struct m_tag *fwd_tag;
struct ip6_hdr *ip6;
struct ifnet *rcvif;
uint32_t plen;
int error;
/*
* Fallback conditions to ip6_input for slow path processing.
*/
ip6 = mtod(m, struct ip6_hdr *);
if (ip6->ip6_nxt == IPPROTO_HOPOPTS ||
IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst) ||
IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) ||
in6_localip(&ip6->ip6_dst))
return (m);
/*
* Check that the amount of data in the buffers
* is as at least much as the IPv6 header would have us expect.
* Trim mbufs if longer than we expect.
* Drop packet if shorter than we expect.
*/
rcvif = m->m_pkthdr.rcvif;
plen = ntohs(ip6->ip6_plen);
if (plen == 0) {
/*
* Jumbograms must have hop-by-hop header and go via
* slow path.
*/
IP6STAT_INC(ip6s_badoptions);
goto dropin;
}
if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
IP6STAT_INC(ip6s_tooshort);
in6_ifstat_inc(rcvif, ifs6_in_truncated);
goto dropin;
}
if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
if (m->m_len == m->m_pkthdr.len) {
m->m_len = sizeof(struct ip6_hdr) + plen;
m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
} else
m_adj(m, sizeof(struct ip6_hdr) + plen -
m->m_pkthdr.len);
}
/*
* Hop limit.
*/
#ifdef IPSTEALTH
if (!V_ip6stealth)
#endif
if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
m = NULL;
goto dropin;
}
bzero(&dst, sizeof(dst));
dst.sin6_family = AF_INET6;
dst.sin6_len = sizeof(dst);
dst.sin6_addr = ip6->ip6_dst;
/*
* Incoming packet firewall processing.
*/
if (!PFIL_HOOKED(&V_inet6_pfil_hook))
goto passin;
if (pfil_run_hooks(&V_inet6_pfil_hook, &m, rcvif, PFIL_IN,
NULL) != 0 || m == NULL)
goto dropin;
/*
* If packet filter sets the M_FASTFWD_OURS flag, this means
* that new destination or next hop is our local address.
* So, we can just go back to ip6_input.
* XXX: should we decrement ip6_hlim in such case?
*
* Also it can forward packet to another destination, e.g.
* M_IP6_NEXTHOP flag is set and fwd_tag is attached to mbuf.
*/
if (m->m_flags & M_FASTFWD_OURS)
return (m);
ip6 = mtod(m, struct ip6_hdr *);
if ((m->m_flags & M_IP6_NEXTHOP) &&
(fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
/*
* Now we will find route to forwarded by pfil destination.
*/
bcopy((fwd_tag + 1), &dst, sizeof(dst));
m->m_flags &= ~M_IP6_NEXTHOP;
m_tag_delete(m, fwd_tag);
} else {
/* Update dst since pfil could change it */
dst.sin6_addr = ip6->ip6_dst;
}
passin:
/*
* Find route to destination.
*/
if (ip6_findroute(&nh, &dst, m) != 0) {
m = NULL;
in6_ifstat_inc(rcvif, ifs6_in_noroute);
goto dropin;
}
/*
* We used slow path processing for packets with scoped addresses.
* So, scope checks aren't needed here.
*/
if (m->m_pkthdr.len > nh.nh_mtu) {
in6_ifstat_inc(nh.nh_ifp, ifs6_in_toobig);
icmp6_error(m, ICMP6_PACKET_TOO_BIG, 0, nh.nh_mtu);
m = NULL;
goto dropout;
}
/*
* Outgoing packet firewall processing.
*/
if (!PFIL_HOOKED(&V_inet6_pfil_hook))
goto passout;
if (pfil_run_hooks(&V_inet6_pfil_hook, &m, nh.nh_ifp, PFIL_OUT,
NULL) != 0 || m == NULL)
goto dropout;
/*
* If packet filter sets the M_FASTFWD_OURS flag, this means
* that new destination or next hop is our local address.
* So, we can just go back to ip6_input.
*
* Also it can forward packet to another destination, e.g.
* M_IP6_NEXTHOP flag is set and fwd_tag is attached to mbuf.
*/
if (m->m_flags & M_FASTFWD_OURS) {
/*
* XXX: we did one hop and should decrement hop limit. But
* now we are the destination and just don't pay attention.
*/
return (m);
}
/*
* Again. A packet filter could change the destination address.
*/
ip6 = mtod(m, struct ip6_hdr *);
if (m->m_flags & M_IP6_NEXTHOP)
fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
else
fwd_tag = NULL;
if (fwd_tag != NULL ||
!IN6_ARE_ADDR_EQUAL(&dst.sin6_addr, &ip6->ip6_dst)) {
if (fwd_tag != NULL) {
bcopy((fwd_tag + 1), &dst, sizeof(dst));
m->m_flags &= ~M_IP6_NEXTHOP;
m_tag_delete(m, fwd_tag);
} else
dst.sin6_addr = ip6->ip6_dst;
/*
* Redo route lookup with new destination address
*/
if (ip6_findroute(&nh, &dst, m) != 0) {
m = NULL;
goto dropout;
}
}
passout:
#ifdef IPSTEALTH
if (!V_ip6stealth)
#endif
{
ip6->ip6_hlim -= IPV6_HLIMDEC;
}
m_clrprotoflags(m); /* Avoid confusing lower layers. */
IP_PROBE(send, NULL, NULL, ip6, nh.nh_ifp, NULL, ip6);
/*
* XXX: we need to use destination address with embedded scope
* zone id, because LLTABLE uses such form of addresses for lookup.
*/
dst.sin6_addr = nh.nh_addr;
if (IN6_IS_SCOPE_LINKLOCAL(&dst.sin6_addr))
dst.sin6_addr.s6_addr16[1] = htons(nh.nh_ifp->if_index & 0xffff);
error = (*nh.nh_ifp->if_output)(nh.nh_ifp, m,
(struct sockaddr *)&dst, NULL);
if (error != 0) {
in6_ifstat_inc(nh.nh_ifp, ifs6_out_discard);
IP6STAT_INC(ip6s_cantforward);
} else {
in6_ifstat_inc(nh.nh_ifp, ifs6_out_forward);
IP6STAT_INC(ip6s_forward);
}
return (NULL);
dropin:
in6_ifstat_inc(rcvif, ifs6_in_discard);
goto drop;
dropout:
in6_ifstat_inc(nh.nh_ifp, ifs6_out_discard);
drop:
if (m != NULL)
m_freem(m);
return (NULL);
}
int
udp6_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp;
struct ip6_hdr *ip6;
struct udphdr *uh;
struct inpcb *in6p;
struct mbuf *opts = NULL;
int off = *offp;
int plen, ulen;
struct sockaddr_in6 udp_in6;
struct socket *so;
struct inpcbinfo *pcbinfo = &udbinfo[0];
IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
ip6 = mtod(m, struct ip6_hdr *);
if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
/* XXX send icmp6 host/port unreach? */
m_freem(m);
return IPPROTO_DONE;
}
udp_stat.udps_ipackets++;
plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
uh = (struct udphdr *)((caddr_t)ip6 + off);
ulen = ntohs((u_short)uh->uh_ulen);
if (plen != ulen) {
udp_stat.udps_badlen++;
goto bad;
}
/*
* Checksum extended UDP header and data.
*/
if (uh->uh_sum == 0)
udp_stat.udps_nosum++;
else if (in6_cksum(m, IPPROTO_UDP, off, ulen) != 0) {
udp_stat.udps_badsum++;
goto bad;
}
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct inpcb *last, *marker;
/*
* Deliver a multicast datagram to all sockets
* for which the local and remote addresses and ports match
* those of the incoming datagram. This allows more than
* one process to receive multicasts on the same port.
* (This really ought to be done for unicast datagrams as
* well, but that would cause problems with existing
* applications that open both address-specific sockets and
* a wildcard socket listening to the same port -- they would
* end up receiving duplicates of every unicast datagram.
* Those applications open the multiple sockets to overcome an
* inadequacy of the UDP socket interface, but for backwards
* compatibility we avoid the problem here rather than
* fixing the interface. Maybe 4.5BSD will remedy this?)
*/
/*
* In a case that laddr should be set to the link-local
* address (this happens in RIPng), the multicast address
* specified in the received packet does not match with
* laddr. To cure this situation, the matching is relaxed
* if the receiving interface is the same as one specified
* in the socket and if the destination multicast address
* matches one of the multicast groups specified in the socket.
*/
/*
* Construct sockaddr format source address.
*/
init_sin6(&udp_in6, m); /* general init */
udp_in6.sin6_port = uh->uh_sport;
/*
* KAME note: traditionally we dropped udpiphdr from mbuf here.
* We need udphdr for IPsec processing so we do that later.
*/
/*
* Locate pcb(s) for datagram.
* (Algorithm copied from raw_intr().)
*/
last = NULL;
marker = in_pcbmarker(mycpuid);
GET_PCBINFO_TOKEN(pcbinfo);
LIST_INSERT_HEAD(&pcbinfo->pcblisthead, marker, inp_list);
while ((in6p = LIST_NEXT(marker, inp_list)) != NULL) {
LIST_REMOVE(marker, inp_list);
LIST_INSERT_AFTER(in6p, marker, inp_list);
if (in6p->inp_flags & INP_PLACEMARKER)
continue;
if (!INP_ISIPV6(in6p))
continue;
if (in6p->in6p_lport != uh->uh_dport)
continue;
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr,
&ip6->ip6_dst) &&
!in6_mcmatch(in6p, &ip6->ip6_dst,
m->m_pkthdr.rcvif))
continue;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
&ip6->ip6_src) ||
in6p->in6p_fport != uh->uh_sport)
continue;
}
if (last != NULL) {
struct mbuf *n;
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject_so(m, last->inp_socket))
ipsec6stat.in_polvio++;
/* do not inject data into pcb */
else
#endif /* IPSEC */
#ifdef FAST_IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject(m, last))
;
else
#endif /* FAST_IPSEC */
if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
/*
* KAME NOTE: do not
* m_copy(m, offset, ...) above.
* ssb_appendaddr() expects M_PKTHDR,
* and m_copy() will copy M_PKTHDR
* only if offset is 0.
*/
so = last->in6p_socket;
if ((last->in6p_flags & IN6P_CONTROLOPTS) ||
(so->so_options & SO_TIMESTAMP)) {
ip6_savecontrol(last, &opts,
ip6, n);
}
m_adj(n, off + sizeof(struct udphdr));
lwkt_gettoken(&so->so_rcv.ssb_token);
if (ssb_appendaddr(&so->so_rcv,
(struct sockaddr *)&udp_in6,
n, opts) == 0) {
m_freem(n);
if (opts)
m_freem(opts);
udp_stat.udps_fullsock++;
} else {
sorwakeup(so);
}
lwkt_reltoken(&so->so_rcv.ssb_token);
opts = NULL;
}
}
last = in6p;
/*
* Don't look for additional matches if this one does
* not have either the SO_REUSEPORT or SO_REUSEADDR
* socket options set. This heuristic avoids searching
* through all pcbs in the common case of a non-shared
* port. It assumes that an application will never
* clear these options after setting them.
*/
if ((last->in6p_socket->so_options &
(SO_REUSEPORT | SO_REUSEADDR)) == 0)
break;
}
LIST_REMOVE(marker, inp_list);
REL_PCBINFO_TOKEN(pcbinfo);
if (last == NULL) {
/*
* No matching pcb found; discard datagram.
* (No need to send an ICMP Port Unreachable
* for a broadcast or multicast datgram.)
*/
udp_stat.udps_noport++;
udp_stat.udps_noportmcast++;
goto bad;
}
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject_so(m, last->inp_socket)) {
ipsec6stat.in_polvio++;
goto bad;
}
#endif /* IPSEC */
#ifdef FAST_IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject(m, last)) {
goto bad;
}
#endif /* FAST_IPSEC */
if (last->in6p_flags & IN6P_CONTROLOPTS
|| last->in6p_socket->so_options & SO_TIMESTAMP)
ip6_savecontrol(last, &opts, ip6, m);
m_adj(m, off + sizeof(struct udphdr));
so = last->in6p_socket;
lwkt_gettoken(&so->so_rcv.ssb_token);
if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *)&udp_in6,
m, opts) == 0) {
udp_stat.udps_fullsock++;
lwkt_reltoken(&so->so_rcv.ssb_token);
goto bad;
}
sorwakeup(so);
lwkt_reltoken(&so->so_rcv.ssb_token);
return IPPROTO_DONE;
}
/*
* Locate pcb for datagram.
*/
in6p = in6_pcblookup_hash(pcbinfo, &ip6->ip6_src, uh->uh_sport,
&ip6->ip6_dst, uh->uh_dport, 1,
m->m_pkthdr.rcvif);
if (in6p == NULL) {
if (log_in_vain) {
char buf[INET6_ADDRSTRLEN];
strcpy(buf, ip6_sprintf(&ip6->ip6_dst));
log(LOG_INFO,
"Connection attempt to UDP [%s]:%d from [%s]:%d\n",
buf, ntohs(uh->uh_dport),
ip6_sprintf(&ip6->ip6_src), ntohs(uh->uh_sport));
}
udp_stat.udps_noport++;
if (m->m_flags & M_MCAST) {
kprintf("UDP6: M_MCAST is set in a unicast packet.\n");
udp_stat.udps_noportmcast++;
goto bad;
}
icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
return IPPROTO_DONE;
}
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject_so(m, in6p->in6p_socket)) {
ipsec6stat.in_polvio++;
goto bad;
}
#endif /* IPSEC */
#ifdef FAST_IPSEC
/*
* Check AH/ESP integrity.
*/
if (ipsec6_in_reject(m, in6p)) {
goto bad;
}
#endif /* FAST_IPSEC */
/*
* Construct sockaddr format source address.
* Stuff source address and datagram in user buffer.
*/
init_sin6(&udp_in6, m); /* general init */
udp_in6.sin6_port = uh->uh_sport;
if (in6p->in6p_flags & IN6P_CONTROLOPTS
|| in6p->in6p_socket->so_options & SO_TIMESTAMP)
ip6_savecontrol(in6p, &opts, ip6, m);
m_adj(m, off + sizeof(struct udphdr));
so = in6p->in6p_socket;
lwkt_gettoken(&so->so_rcv.ssb_token);
if (ssb_appendaddr(&so->so_rcv, (struct sockaddr *)&udp_in6,
m, opts) == 0) {
udp_stat.udps_fullsock++;
lwkt_reltoken(&so->so_rcv.ssb_token);
goto bad;
}
sorwakeup(so);
lwkt_reltoken(&so->so_rcv.ssb_token);
return IPPROTO_DONE;
bad:
if (m)
m_freem(m);
if (opts)
m_freem(opts);
return IPPROTO_DONE;
}
/*
* Forward a packet. If some error occurs return the sender
* an icmp packet. Note we can't always generate a meaningful
* icmp message because icmp doesn't have a large enough repertoire
* of codes and types.
*
* If not forwarding, just drop the packet. This could be confusing
* if ipforwarding was zero but some routing protocol was advancing
* us as a gateway to somewhere. However, we must let the routing
* protocol deal with that.
*
*/
void
ip6_forward(struct mbuf *m, int srcrt)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct sockaddr_in6 *dst = NULL;
struct rtentry *rt = NULL;
struct route_in6 rin6;
int error, type = 0, code = 0;
struct mbuf *mcopy = NULL;
struct ifnet *origifp; /* maybe unnecessary */
u_int32_t inzone, outzone;
struct in6_addr src_in6, dst_in6, odst;
#ifdef IPSEC
struct secpolicy *sp = NULL;
#endif
#ifdef SCTP
int sw_csum;
#endif
struct m_tag *fwd_tag;
char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
#ifdef IPSEC
/*
* Check AH/ESP integrity.
*/
/*
* Don't increment ip6s_cantforward because this is the check
* before forwarding packet actually.
*/
if (ipsec6_in_reject(m, NULL)) {
IPSEC6STAT_INC(ips_in_polvio);
m_freem(m);
return;
}
#endif /* IPSEC */
/*
* Do not forward packets to multicast destination (should be handled
* by ip6_mforward().
* Do not forward packets with unspecified source. It was discussed
* in July 2000, on the ipngwg mailing list.
*/
if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 ||
IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
IP6STAT_INC(ip6s_cantforward);
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
if (V_ip6_log_time + V_ip6_log_interval < time_uptime) {
V_ip6_log_time = time_uptime;
log(LOG_DEBUG,
"cannot forward "
"from %s to %s nxt %d received on %s\n",
ip6_sprintf(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst),
ip6->ip6_nxt,
if_name(m->m_pkthdr.rcvif));
}
m_freem(m);
return;
}
#ifdef IPSTEALTH
if (!V_ip6stealth) {
#endif
if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
return;
}
ip6->ip6_hlim -= IPV6_HLIMDEC;
#ifdef IPSTEALTH
}
#endif
/*
* Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU -
* size of IPv6 + ICMPv6 headers) bytes of the packet in case
* we need to generate an ICMP6 message to the src.
* Thanks to M_EXT, in most cases copy will not occur.
*
* It is important to save it before IPsec processing as IPsec
* processing may modify the mbuf.
*/
mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
#ifdef IPSEC
/* get a security policy for this packet */
sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND,
IP_FORWARDING, &error);
if (sp == NULL) {
IPSEC6STAT_INC(ips_out_inval);
IP6STAT_INC(ip6s_cantforward);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
error = 0;
/* check policy */
switch (sp->policy) {
case IPSEC_POLICY_DISCARD:
/*
* This packet is just discarded.
*/
IPSEC6STAT_INC(ips_out_polvio);
IP6STAT_INC(ip6s_cantforward);
KEY_FREESP(&sp);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
/* no need to do IPsec. */
KEY_FREESP(&sp);
goto skip_ipsec;
case IPSEC_POLICY_IPSEC:
if (sp->req == NULL) {
/* XXX should be panic ? */
printf("ip6_forward: No IPsec request specified.\n");
IP6STAT_INC(ip6s_cantforward);
KEY_FREESP(&sp);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
m_freem(m);
return;
}
/* do IPsec */
break;
case IPSEC_POLICY_ENTRUST:
default:
/* should be panic ?? */
printf("ip6_forward: Invalid policy found. %d\n", sp->policy);
KEY_FREESP(&sp);
goto skip_ipsec;
}
{
struct ipsecrequest *isr = NULL;
/*
* when the kernel forwards a packet, it is not proper to apply
* IPsec transport mode to the packet is not proper. this check
* avoid from this.
* at present, if there is even a transport mode SA request in the
* security policy, the kernel does not apply IPsec to the packet.
* this check is not enough because the following case is valid.
* ipsec esp/tunnel/xxx-xxx/require esp/transport//require;
*/
for (isr = sp->req; isr; isr = isr->next) {
if (isr->saidx.mode == IPSEC_MODE_ANY)
goto doipsectunnel;
if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
goto doipsectunnel;
}
/*
* if there's no need for tunnel mode IPsec, skip.
*/
if (!isr)
goto skip_ipsec;
doipsectunnel:
/*
* All the extension headers will become inaccessible
* (since they can be encrypted).
* Don't panic, we need no more updates to extension headers
* on inner IPv6 packet (since they are now encapsulated).
*
* IPv6 [ESP|AH] IPv6 [extension headers] payload
*/
/*
* If we need to encapsulate the packet, do it here
* ipsec6_proces_packet will send the packet using ip6_output
*/
error = ipsec6_process_packet(m, sp->req);
KEY_FREESP(&sp);
if (error == EJUSTRETURN) {
/*
* We had a SP with a level of 'use' and no SA. We
* will just continue to process the packet without
* IPsec processing.
*/
error = 0;
goto skip_ipsec;
}
if (error) {
/* mbuf is already reclaimed in ipsec6_process_packet. */
switch (error) {
case EHOSTUNREACH:
case ENETUNREACH:
case EMSGSIZE:
case ENOBUFS:
case ENOMEM:
break;
default:
printf("ip6_output (ipsec): error code %d\n", error);
/* FALLTHROUGH */
case ENOENT:
/* don't show these error codes to the user */
break;
}
IP6STAT_INC(ip6s_cantforward);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#else
m_freem(mcopy);
#endif
}
return;
} else {
/*
* In the FAST IPSec case we have already
* re-injected the packet and it has been freed
* by the ipsec_done() function. So, just clean
* up after ourselves.
*/
m = NULL;
goto freecopy;
}
}
skip_ipsec:
#endif
again:
bzero(&rin6, sizeof(struct route_in6));
dst = (struct sockaddr_in6 *)&rin6.ro_dst;
dst->sin6_len = sizeof(struct sockaddr_in6);
dst->sin6_family = AF_INET6;
dst->sin6_addr = ip6->ip6_dst;
again2:
rin6.ro_rt = in6_rtalloc1((struct sockaddr *)dst, 0, 0, M_GETFIB(m));
if (rin6.ro_rt != NULL)
RT_UNLOCK(rin6.ro_rt);
else {
IP6STAT_INC(ip6s_noroute);
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
goto bad;
}
rt = rin6.ro_rt;
/*
* Source scope check: if a packet can't be delivered to its
* destination for the reason that the destination is beyond the scope
* of the source address, discard the packet and return an icmp6
* destination unreachable error with Code 2 (beyond scope of source
* address). We use a local copy of ip6_src, since in6_setscope()
* will possibly modify its first argument.
* [draft-ietf-ipngwg-icmp-v3-04.txt, Section 3.1]
*/
src_in6 = ip6->ip6_src;
if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) {
/* XXX: this should not happen */
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
goto bad;
}
if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) {
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
goto bad;
}
if (inzone != outzone) {
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard);
if (V_ip6_log_time + V_ip6_log_interval < time_uptime) {
V_ip6_log_time = time_uptime;
log(LOG_DEBUG,
"cannot forward "
"src %s, dst %s, nxt %d, rcvif %s, outif %s\n",
ip6_sprintf(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst),
ip6->ip6_nxt,
if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp));
}
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
goto bad;
}
/*
* Destination scope check: if a packet is going to break the scope
* zone of packet's destination address, discard it. This case should
* usually be prevented by appropriately-configured routing table, but
* we need an explicit check because we may mistakenly forward the
* packet to a different zone by (e.g.) a default route.
*/
dst_in6 = ip6->ip6_dst;
if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 ||
in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 ||
inzone != outzone) {
IP6STAT_INC(ip6s_cantforward);
IP6STAT_INC(ip6s_badscope);
goto bad;
}
if (m->m_pkthdr.len > IN6_LINKMTU(rt->rt_ifp)) {
in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig);
if (mcopy) {
u_long mtu;
#ifdef IPSEC
struct secpolicy *sp;
int ipsecerror;
size_t ipsechdrsiz;
#endif /* IPSEC */
mtu = IN6_LINKMTU(rt->rt_ifp);
#ifdef IPSEC
/*
* When we do IPsec tunnel ingress, we need to play
* with the link value (decrement IPsec header size
* from mtu value). The code is much simpler than v4
* case, as we have the outgoing interface for
* encapsulated packet as "rt->rt_ifp".
*/
sp = ipsec_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
IP_FORWARDING, &ipsecerror);
if (sp) {
ipsechdrsiz = ipsec_hdrsiz(mcopy,
IPSEC_DIR_OUTBOUND, NULL);
if (ipsechdrsiz < mtu)
mtu -= ipsechdrsiz;
}
/*
* if mtu becomes less than minimum MTU,
* tell minimum MTU (and I'll need to fragment it).
*/
if (mtu < IPV6_MMTU)
mtu = IPV6_MMTU;
#endif /* IPSEC */
icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
}
goto bad;
}
if (rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in6 *)rt->rt_gateway;
/*
* If we are to forward the packet using the same interface
* as one we got the packet from, perhaps we should send a redirect
* to sender to shortcut a hop.
* Only send redirect if source is sending directly to us,
* and if packet was not source routed (or has any options).
* Also, don't send redirect if forwarding using a route
* modified by a redirect.
*/
if (V_ip6_sendredirects && 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) {
/*
* If the incoming interface is equal to the outgoing
* one, and the link attached to the interface is
* point-to-point, then it will be highly probable
* that a routing loop occurs. Thus, we immediately
* drop the packet and send an ICMPv6 error message.
*
* type/code is based on suggestion by Rich Draves.
* not sure if it is the best pick.
*/
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADDR, 0);
goto bad;
}
type = ND_REDIRECT;
}
/*
* Fake scoped addresses. Note that even link-local source or
* destinaion can appear, if the originating node just sends the
* packet to us (without address resolution for the destination).
* Since both icmp6_error and icmp6_redirect_output fill the embedded
* link identifiers, we can do this stuff after making a copy for
* returning an error.
*/
if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
/*
* See corresponding comments in ip6_output.
* XXX: but is it possible that ip6_forward() sends a packet
* to a loopback interface? I don't think so, and thus
* I bark here. ([email protected])
* XXX: it is common to route invalid packets to loopback.
* also, the codepath will be visited on use of ::1 in
* rthdr. (itojun)
*/
#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(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst),
ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif),
if_name(rt->rt_ifp));
}
/* we can just use rcvif in forwarding. */
origifp = m->m_pkthdr.rcvif;
}
else
origifp = rt->rt_ifp;
/*
* clear embedded scope identifiers if necessary.
* in6_clearscope will touch the addresses only when necessary.
*/
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
/* Jump over all PFIL processing if hooks are not active. */
if (!PFIL_HOOKED(&V_inet6_pfil_hook))
goto pass;
odst = ip6->ip6_dst;
/* Run through list of hooks for output packets. */
error = pfil_run_hooks(&V_inet6_pfil_hook, &m, rt->rt_ifp, PFIL_OUT, NULL);
if (error != 0 || m == NULL)
goto freecopy; /* consumed by filter */
ip6 = mtod(m, struct ip6_hdr *);
/* See if destination IP address was changed by packet filter. */
if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
m->m_flags |= M_SKIP_FIREWALL;
/* If destination is now ourself drop to ip6_input(). */
if (in6_localip(&ip6->ip6_dst)) {
m->m_flags |= M_FASTFWD_OURS;
if (m->m_pkthdr.rcvif == NULL)
m->m_pkthdr.rcvif = V_loif;
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
m->m_pkthdr.csum_flags |=
CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xffff;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
#endif
error = netisr_queue(NETISR_IPV6, m);
goto out;
} else
goto again; /* Redo the routing table lookup. */
}
/* See if local, if yes, send it to netisr. */
if (m->m_flags & M_FASTFWD_OURS) {
if (m->m_pkthdr.rcvif == NULL)
m->m_pkthdr.rcvif = V_loif;
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
m->m_pkthdr.csum_flags |=
CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xffff;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
#endif
error = netisr_queue(NETISR_IPV6, m);
goto out;
}
/* Or forward to some other address? */
if ((m->m_flags & M_IP6_NEXTHOP) &&
(fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
dst = (struct sockaddr_in6 *)&rin6.ro_dst;
bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in6));
m->m_flags |= M_SKIP_FIREWALL;
m->m_flags &= ~M_IP6_NEXTHOP;
m_tag_delete(m, fwd_tag);
goto again2;
}
pass:
error = nd6_output(rt->rt_ifp, origifp, m, dst, rt);
if (error) {
in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard);
IP6STAT_INC(ip6s_cantforward);
} else {
IP6STAT_INC(ip6s_forward);
in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward);
if (type)
IP6STAT_INC(ip6s_redirectsent);
else {
if (mcopy)
goto freecopy;
}
}
if (mcopy == NULL)
goto out;
switch (error) {
case 0:
if (type == ND_REDIRECT) {
icmp6_redirect_output(mcopy, rt);
goto out;
}
goto freecopy;
case EMSGSIZE:
/* xxx MTU is constant in PPP? */
goto freecopy;
case ENOBUFS:
/* Tell source to slow down like source quench in IP? */
goto freecopy;
case ENETUNREACH: /* shouldn't happen, checked above */
case EHOSTUNREACH:
case ENETDOWN:
case EHOSTDOWN:
default:
type = ICMP6_DST_UNREACH;
code = ICMP6_DST_UNREACH_ADDR;
break;
}
icmp6_error(mcopy, type, code, 0);
goto out;
freecopy:
m_freem(mcopy);
goto out;
bad:
m_freem(m);
out:
if (rt != NULL)
RTFREE(rt);
}
void
ip6_forward(struct mbuf *m, int srcrt)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
const struct sockaddr_in6 *dst;
struct rtentry *rt;
int error = 0, type = 0, code = 0;
struct mbuf *mcopy = NULL;
struct ifnet *origifp; /* maybe unnecessary */
uint32_t inzone, outzone;
struct in6_addr src_in6, dst_in6;
#ifdef IPSEC
int needipsec = 0;
struct secpolicy *sp = NULL;
#endif
/*
* Clear any in-bound checksum flags for this packet.
*/
m->m_pkthdr.csum_flags = 0;
/*
* Do not forward packets to multicast destination (should be handled
* by ip6_mforward().
* Do not forward packets with unspecified source. It was discussed
* in July 2000, on ipngwg mailing list.
*/
if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 ||
IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
ip6_cantforward(ip6, m->m_pkthdr.rcvif, NULL,
((m->m_flags & (M_BCAST|M_MCAST)) != 0) ? "bcast/mcast" :
IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ? "mcast/dst" :
"unspec/src");
m_freem(m);
return;
}
if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
icmp6_error(m, ICMP6_TIME_EXCEEDED,
ICMP6_TIME_EXCEED_TRANSIT, 0);
return;
}
ip6->ip6_hlim -= IPV6_HLIMDEC;
/*
* Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU -
* size of IPv6 + ICMPv6 headers) bytes of the packet in case
* we need to generate an ICMP6 message to the src.
* Thanks to M_EXT, in most cases copy will not occur.
*
* It is important to save it before IPsec processing as IPsec
* processing may modify the mbuf.
*/
mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
#ifdef IPSEC
if (ipsec_used) {
/* Check the security policy (SP) for the packet */
sp = ipsec6_check_policy(m, NULL, 0, &needipsec, &error);
if (error != 0) {
/*
* Hack: -EINVAL is used to signal that a packet
* should be silently discarded. This is typically
* because we asked key management for an SA and
* it was delayed (e.g. kicked up to IKE).
*/
if (error == -EINVAL)
error = 0;
goto freecopy;
}
}
#endif /* IPSEC */
if (srcrt) {
union {
struct sockaddr dst;
struct sockaddr_in6 dst6;
} u;
sockaddr_in6_init(&u.dst6, &ip6->ip6_dst, 0, 0, 0);
if ((rt = rtcache_lookup(&ip6_forward_rt, &u.dst)) == NULL) {
IP6_STATINC(IP6_STAT_NOROUTE);
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
m_freem(m);
return;
}
} else if ((rt = rtcache_validate(&ip6_forward_rt)) == NULL &&
(rt = rtcache_update(&ip6_forward_rt, 1)) == NULL) {
/*
* rtcache_getdst(ip6_forward_rt)->sin6_addr was equal to
* ip6->ip6_dst
*/
IP6_STATINC(IP6_STAT_NOROUTE);
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */
if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
}
m_freem(m);
return;
}
dst = satocsin6(rtcache_getdst(&ip6_forward_rt));
/*
* Source scope check: if a packet can't be delivered to its
* destination for the reason that the destination is beyond the scope
* of the source address, discard the packet and return an icmp6
* destination unreachable error with Code 2 (beyond scope of source
* address). We use a local copy of ip6_src, since in6_setscope()
* will possibly modify its first argument.
* [draft-ietf-ipngwg-icmp-v3-07, Section 3.1]
*/
src_in6 = ip6->ip6_src;
inzone = outzone = ~0;
if (in6_setscope(&src_in6, rt->rt_ifp, &outzone) != 0 ||
in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone) != 0 ||
inzone != outzone) {
ip6_cantforward(ip6, m->m_pkthdr.rcvif, rt->rt_ifp,
"src[%s] inzone %d outzone %d",
in6_getscopename(&ip6->ip6_src), inzone, outzone);
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
m_freem(m);
return;
}
#ifdef IPSEC
/*
* If we need to encapsulate the packet, do it here
* ipsec6_proces_packet will send the packet using ip6_output
*/
if (needipsec) {
int s = splsoftnet();
error = ipsec6_process_packet(m, sp->req);
splx(s);
if (mcopy)
goto freecopy;
}
#endif
/*
* Destination scope check: if a packet is going to break the scope
* zone of packet's destination address, discard it. This case should
* usually be prevented by appropriately-configured routing table, but
* we need an explicit check because we may mistakenly forward the
* packet to a different zone by (e.g.) a default route.
*/
dst_in6 = ip6->ip6_dst;
inzone = outzone = ~0;
if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 ||
in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 ||
inzone != outzone) {
ip6_cantforward(ip6, m->m_pkthdr.rcvif, rt->rt_ifp,
"dst[%s] inzone %d outzone %d",
in6_getscopename(&ip6->ip6_dst), inzone, outzone);
if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
m_freem(m);
return;
}
if (m->m_pkthdr.len > IN6_LINKMTU(rt->rt_ifp)) {
in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig);
if (mcopy) {
u_long mtu;
mtu = IN6_LINKMTU(rt->rt_ifp);
icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
}
m_freem(m);
return;
}
if (rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in6 *)rt->rt_gateway;
/*
* If we are to forward the packet using the same interface
* as one we got the packet from, perhaps we should send a redirect
* to sender to shortcut a hop.
* Only send redirect if source is sending directly to us,
* and if packet was not source routed (or has any options).
* Also, don't send redirect if forwarding using a route
* modified by a redirect.
*/
if (rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt && ip6_sendredirects &&
(rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0) {
if ((rt->rt_ifp->if_flags & IFF_POINTOPOINT) &&
nd6_is_addr_neighbor(
satocsin6(rtcache_getdst(&ip6_forward_rt)),
rt->rt_ifp)) {
/*
* If the incoming interface is equal to the outgoing
* one, the link attached to the interface is
* point-to-point, and the IPv6 destination is
* regarded as on-link on the link, then it will be
* highly probable that the destination address does
* not exist on the link and that the packet is going
* to loop. Thus, we immediately drop the packet and
* send an ICMPv6 error message.
* For other routing loops, we dare to let the packet
* go to the loop, so that a remote diagnosing host
* can detect the loop by traceroute.
* type/code is based on suggestion by Rich Draves.
* not sure if it is the best pick.
*/
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADDR, 0);
m_freem(m);
return;
}
type = ND_REDIRECT;
}
/*
* Fake scoped addresses. Note that even link-local source or
* destinaion can appear, if the originating node just sends the
* packet to us (without address resolution for the destination).
* Since both icmp6_error and icmp6_redirect_output fill the embedded
* link identifiers, we can do this stuff after making a copy for
* returning an error.
*/
if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
/*
* See corresponding comments in ip6_output.
* XXX: but is it possible that ip6_forward() sends a packet
* to a loopback interface? I don't think so, and thus
* I bark here. ([email protected])
* XXX: it is common to route invalid packets to loopback.
* also, the codepath will be visited on use of ::1 in
* rthdr. (itojun)
*/
#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));
}
/* we can just use rcvif in forwarding. */
origifp = m->m_pkthdr.rcvif;
}
else
origifp = rt->rt_ifp;
/*
* clear embedded scope identifiers if necessary.
* in6_clearscope will touch the addresses only when necessary.
*/
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
/*
* Run through list of hooks for output packets.
*/
if ((error = pfil_run_hooks(inet6_pfil_hook, &m, rt->rt_ifp,
PFIL_OUT)) != 0)
goto senderr;
if (m == NULL)
goto freecopy;
ip6 = mtod(m, struct ip6_hdr *);
error = nd6_output(rt->rt_ifp, origifp, m, dst, rt);
if (error) {
in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard);
IP6_STATINC(IP6_STAT_CANTFORWARD);
} else {
IP6_STATINC(IP6_STAT_FORWARD);
in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward);
if (type)
IP6_STATINC(IP6_STAT_REDIRECTSENT);
else {
#ifdef GATEWAY
if (m->m_flags & M_CANFASTFWD)
ip6flow_create(&ip6_forward_rt, m);
#endif
if (mcopy)
goto freecopy;
}
}
senderr:
if (mcopy == NULL)
return;
switch (error) {
case 0:
if (type == ND_REDIRECT) {
icmp6_redirect_output(mcopy, rt);
return;
}
goto freecopy;
case EMSGSIZE:
/* xxx MTU is constant in PPP? */
goto freecopy;
case ENOBUFS:
/* Tell source to slow down like source quench in IP? */
goto freecopy;
case ENETUNREACH: /* shouldn't happen, checked above */
case EHOSTUNREACH:
case ENETDOWN:
case EHOSTDOWN:
default:
type = ICMP6_DST_UNREACH;
code = ICMP6_DST_UNREACH_ADDR;
break;
}
icmp6_error(mcopy, type, code, 0);
return;
freecopy:
m_freem(mcopy);
return;
}
void
ip6_input (T_NET_BUF *input)
{
T_IP6_HDR *ip6h;
T_IN6_IFADDR *ia6;
T_IFNET *ifp;
ER_UINT noff;
uint_t next, nest, plen, offp, nextp;
uint_t (*func)(T_NET_BUF **, uint_t *, uint_t *);
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_OCTETS], input->len - IF_HDR_SIZE);
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_PACKETS], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInReceives, 1);
/* IP ヘッダの長さをチェックする。*/
if (input->len < IF_IP6_HDR_SIZE) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_SHORT], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInHdrErrors, 1);
goto buf_rel;
}
ip6h = GET_IP6_HDR(input);
/* バージョンをチェックする。*/
if (IP6_VCF_V(ntohl(ip6h->vcf)) != IPV6_VERSION) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_VER], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInHdrErrors, 1);
goto buf_rel;
}
/*
* 次のデータグラムは破棄する。
*
* ・始点アドレスがマルチキャスト
* ・終点アドレスが未定義
*
* ネットワークインタフェースがループバックでないとき、
* 次のデータグラムも破棄する。
*
* ・始点アドレスがループバック
* ・終点アドレスがループバック
*
* 悪意のあるユーザが TCP/UDP スタックの混乱や
* セキュリティチェックをバイパスするため、IPv4
* マップアドレスを悪用することを防ぐため
* 以下のデータグラムは破棄する。
*
* ・始点アドレスが ::ffff:127.0.0.1
* ・終点アドレスが ::ffff:127.0.0.1
*/
if (IN6_IS_ADDR_MULTICAST(&ip6h->src) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6h->dst)) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_ADDR], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInAddrErrors, 1);
goto buf_rel;
}
if (IN6_IS_ADDR_V4MAPPED(&ip6h->src) ||
IN6_IS_ADDR_V4MAPPED(&ip6h->dst)) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_ADDR], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInAddrErrors, 1);
goto buf_rel;
}
#ifdef SUPPORT_LOOP
#else /* of #ifdef SUPPORT_LOOP */
if (IN6_IS_ADDR_LOOPBACK(&ip6h->src) ||
IN6_IS_ADDR_LOOPBACK(&ip6h->dst)) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_ADDR], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInAddrErrors, 1);
goto buf_rel;
}
#endif /* of #ifdef SUPPORT_LOOP */
ifp = IF_GET_IFNET();
if (IN6_IS_ADDR_MULTICAST(&ip6h->dst)) {
/* 宛先がマルチキャストの場合の処理 */
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInMcastPkts, 1);
if (!in6_lookup_multi(ifp, &ip6h->dst)) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_ADDR], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInAddrErrors, 1);
goto buf_rel;
}
}
else {
if ((ia6 = in6_lookup_ifaddr(ifp, &ip6h->dst)) == NULL) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_ADDR], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInAddrErrors, 1);
goto buf_rel;
}
/* アドレスが未解決の場合はデータグラムを破棄する。*/
if (IFA6_IS_NOTREADY(ia6)) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_ADDR], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInAddrErrors, 1);
goto buf_rel;
}
}
/* オフセットを設定する。*/
offp = GET_IP6_NEXT_HDR(input) - input->buf;
/* ペイロード長を取り出す。*/
plen = ntohs(ip6h->plen);
/* 次ヘッダの位置を初期化する。*/
nextp = offsetof(T_IP6_HDR, next);
/*
* 中継点 (Hop-by-Hop) オプションヘッダのチェック
*/
if (ip6h->next == IPPROTO_HOPOPTS) {
/* 中継点ヘッダの長さをチェックする。*/
if (plen < sizeof(T_IP6_HBH_HDR)) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_SHORT], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInHdrErrors, 1);
goto buf_rel;
}
if ((noff = ip6_hopopts_input(input, &offp, &nextp)) < 0) {
if (noff == IP6_OPT_RET_ERR) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_PACKETS], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInHdrErrors, 1);
goto buf_rel;
}
else if (noff == IP6_OPT_RET_REL) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_PACKETS], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInHdrErrors, 1);
return;
}
}
/*
* ペイロード長が 0 で、中継点オプションがあるときは、
* 巨大ペイロード・オプションが含まれなければならない。
* このとき、巨大ペイロード・オプションにある
* ペイロード長をチェックする必要があるが、本実装では、
* 巨大ペイロード・オプションを未知のオプションとして
* 扱うので、何もしない。
*/
next = ((T_IP6_HBH_HDR *)(ip6h + 1))->next;
}
else
next = ip6h->next;
/* IPv6 データグラム長をチェックする。*/
if (input->len - IF_IP6_HDR_SIZE < plen) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_SHORT], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInTruncatedPkts, 1);
goto buf_rel;
}
else if (input->len > IF_IP6_HDR_SIZE + plen)
input->len = IF_IP6_HDR_SIZE + plen;
/* 上位プロトコル処理関数を呼び出す。*/
nest = 0;
while (next != IPPROTO_DONE) {
if (++ nest > IP6_HDR_NEST_LIMIT) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_PROTO], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInUnknownProtos, 1);
goto buf_rel;
}
else if ((func = get_upper_proto(next)) == NULL) {
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_PROTO], 1);
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_PACKETS], 1);
NET_COUNT_MIB(in6_ifstat.ipv6IfStatsInUnknownProtos, 1);
/* icmp6_error でネットワークバッファを開放する。*/
icmp6_error(input, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_NEXT_HEADER, nextp);
return;
}
else {
next = (*func)(&input, &offp, &nextp);
}
}
return;
buf_rel:
NET_COUNT_IP6(net_count_ip6[NC_IP6_IN_ERR_PACKETS], 1);
syscall(rel_net_buf(input));
}
int
udp6_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp;
struct ifnet *ifp;
struct ip6_hdr *ip6;
struct udphdr *uh;
struct inpcb *inp;
struct inpcbinfo *pcbinfo;
struct udpcb *up;
int off = *offp;
int cscov_partial;
int plen, ulen;
struct sockaddr_in6 fromsa;
struct m_tag *fwd_tag;
uint16_t uh_sum;
uint8_t nxt;
ifp = m->m_pkthdr.rcvif;
ip6 = mtod(m, struct ip6_hdr *);
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
ip6 = mtod(m, struct ip6_hdr *);
uh = (struct udphdr *)((caddr_t)ip6 + off);
#else
IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(*uh));
if (!uh)
return (IPPROTO_DONE);
#endif
UDPSTAT_INC(udps_ipackets);
/*
* Destination port of 0 is illegal, based on RFC768.
*/
if (uh->uh_dport == 0)
goto badunlocked;
plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
ulen = ntohs((u_short)uh->uh_ulen);
nxt = proto;
cscov_partial = (nxt == IPPROTO_UDPLITE) ? 1 : 0;
if (nxt == IPPROTO_UDPLITE) {
/* Zero means checksum over the complete packet. */
if (ulen == 0)
ulen = plen;
if (ulen == plen)
cscov_partial = 0;
if ((ulen < sizeof(struct udphdr)) || (ulen > plen)) {
/* XXX: What is the right UDPLite MIB counter? */
goto badunlocked;
}
if (uh->uh_sum == 0) {
/* XXX: What is the right UDPLite MIB counter? */
goto badunlocked;
}
} else {
if ((ulen < sizeof(struct udphdr)) || (plen != ulen)) {
UDPSTAT_INC(udps_badlen);
goto badunlocked;
}
if (uh->uh_sum == 0) {
UDPSTAT_INC(udps_nosum);
goto badunlocked;
}
}
if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) &&
!cscov_partial) {
if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
uh_sum = m->m_pkthdr.csum_data;
else
uh_sum = in6_cksum_pseudo(ip6, ulen, nxt,
m->m_pkthdr.csum_data);
uh_sum ^= 0xffff;
} else
uh_sum = in6_cksum_partial(m, nxt, off, plen, ulen);
if (uh_sum != 0) {
UDPSTAT_INC(udps_badsum);
goto badunlocked;
}
/*
* Construct sockaddr format source address.
*/
init_sin6(&fromsa, m);
fromsa.sin6_port = uh->uh_sport;
pcbinfo = udp_get_inpcbinfo(nxt);
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct inpcb *last;
struct inpcbhead *pcblist;
struct ip6_moptions *imo;
INP_INFO_RLOCK(pcbinfo);
/*
* In the event that laddr should be set to the link-local
* address (this happens in RIPng), the multicast address
* specified in the received packet will not match laddr. To
* handle this situation, matching is relaxed if the
* receiving interface is the same as one specified in the
* socket and if the destination multicast address matches
* one of the multicast groups specified in the socket.
*/
/*
* KAME note: traditionally we dropped udpiphdr from mbuf
* here. We need udphdr for IPsec processing so we do that
* later.
*/
pcblist = udp_get_pcblist(nxt);
last = NULL;
LIST_FOREACH(inp, pcblist, inp_list) {
if ((inp->inp_vflag & INP_IPV6) == 0)
continue;
if (inp->inp_lport != uh->uh_dport)
continue;
if (inp->inp_fport != 0 &&
inp->inp_fport != uh->uh_sport)
continue;
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
&ip6->ip6_dst))
continue;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
&ip6->ip6_src) ||
inp->inp_fport != uh->uh_sport)
continue;
}
/*
* XXXRW: Because we weren't holding either the inpcb
* or the hash lock when we checked for a match
* before, we should probably recheck now that the
* inpcb lock is (supposed to be) held.
*/
/*
* Handle socket delivery policy for any-source
* and source-specific multicast. [RFC3678]
*/
imo = inp->in6p_moptions;
if (imo && IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct sockaddr_in6 mcaddr;
int blocked;
INP_RLOCK(inp);
bzero(&mcaddr, sizeof(struct sockaddr_in6));
mcaddr.sin6_len = sizeof(struct sockaddr_in6);
mcaddr.sin6_family = AF_INET6;
mcaddr.sin6_addr = ip6->ip6_dst;
blocked = im6o_mc_filter(imo, ifp,
(struct sockaddr *)&mcaddr,
(struct sockaddr *)&fromsa);
if (blocked != MCAST_PASS) {
if (blocked == MCAST_NOTGMEMBER)
IP6STAT_INC(ip6s_notmember);
if (blocked == MCAST_NOTSMEMBER ||
blocked == MCAST_MUTED)
UDPSTAT_INC(udps_filtermcast);
INP_RUNLOCK(inp); /* XXX */
continue;
}
INP_RUNLOCK(inp);
}
if (last != NULL) {
struct mbuf *n;
if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
INP_RLOCK(last);
UDP_PROBE(receive, NULL, last, ip6,
last, uh);
if (udp6_append(last, n, off, &fromsa))
goto inp_lost;
INP_RUNLOCK(last);
}
}
last = inp;
/*
* Don't look for additional matches if this one does
* not have either the SO_REUSEPORT or SO_REUSEADDR
* socket options set. This heuristic avoids
* searching through all pcbs in the common case of a
* non-shared port. It assumes that an application
* will never clear these options after setting them.
*/
if ((last->inp_socket->so_options &
(SO_REUSEPORT|SO_REUSEADDR)) == 0)
break;
}
if (last == NULL) {
/*
* No matching pcb found; discard datagram. (No need
* to send an ICMP Port Unreachable for a broadcast
* or multicast datgram.)
*/
UDPSTAT_INC(udps_noport);
UDPSTAT_INC(udps_noportmcast);
goto badheadlocked;
}
INP_RLOCK(last);
INP_INFO_RUNLOCK(pcbinfo);
UDP_PROBE(receive, NULL, last, ip6, last, uh);
if (udp6_append(last, m, off, &fromsa) == 0)
INP_RUNLOCK(last);
inp_lost:
return (IPPROTO_DONE);
}
/*
* Locate pcb for datagram.
*/
/*
* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
*/
if ((m->m_flags & M_IP6_NEXTHOP) &&
(fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
struct sockaddr_in6 *next_hop6;
next_hop6 = (struct sockaddr_in6 *)(fwd_tag + 1);
/*
* Transparently forwarded. Pretend to be the destination.
* Already got one like this?
*/
inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif, m);
if (!inp) {
/*
* It's new. Try to find the ambushing socket.
* Because we've rewritten the destination address,
* any hardware-generated hash is ignored.
*/
inp = in6_pcblookup(pcbinfo, &ip6->ip6_src,
uh->uh_sport, &next_hop6->sin6_addr,
next_hop6->sin6_port ? htons(next_hop6->sin6_port) :
uh->uh_dport, INPLOOKUP_WILDCARD |
INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif);
}
/* Remove the tag from the packet. We don't need it anymore. */
m_tag_delete(m, fwd_tag);
m->m_flags &= ~M_IP6_NEXTHOP;
} else
inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
m->m_pkthdr.rcvif, m);
if (inp == NULL) {
if (udp_log_in_vain) {
char ip6bufs[INET6_ADDRSTRLEN];
char ip6bufd[INET6_ADDRSTRLEN];
log(LOG_INFO,
"Connection attempt to UDP [%s]:%d from [%s]:%d\n",
ip6_sprintf(ip6bufd, &ip6->ip6_dst),
ntohs(uh->uh_dport),
ip6_sprintf(ip6bufs, &ip6->ip6_src),
ntohs(uh->uh_sport));
}
UDPSTAT_INC(udps_noport);
if (m->m_flags & M_MCAST) {
printf("UDP6: M_MCAST is set in a unicast packet.\n");
UDPSTAT_INC(udps_noportmcast);
goto badunlocked;
}
if (V_udp_blackhole)
goto badunlocked;
if (badport_bandlim(BANDLIM_ICMP6_UNREACH) < 0)
goto badunlocked;
icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
return (IPPROTO_DONE);
}
INP_RLOCK_ASSERT(inp);
up = intoudpcb(inp);
if (cscov_partial) {
if (up->u_rxcslen == 0 || up->u_rxcslen > ulen) {
INP_RUNLOCK(inp);
m_freem(m);
return (IPPROTO_DONE);
}
}
UDP_PROBE(receive, NULL, inp, ip6, inp, uh);
if (udp6_append(inp, m, off, &fromsa) == 0)
INP_RUNLOCK(inp);
return (IPPROTO_DONE);
badheadlocked:
INP_INFO_RUNLOCK(pcbinfo);
badunlocked:
if (m)
m_freem(m);
return (IPPROTO_DONE);
}
void
nd6_timer (void)
{
T_IFNET *ifp = IF_GET_IFNET();
T_LLINFO_ND6 *ln;
SYSTIM now;
int_t ix;
/* 近隣キャッシュの処理 */
syscall(wai_sem(SEM_ND6_CACHE));
syscall(get_tim(&now));
for (ix = NUM_ND6_CACHE_ENTRY; ix -- > 0; ) {
ln = &nd6_cache[ix];
if (ln->state >= ND6_LLINFO_NO_STATE && (int32_t)(ln->expire - now) < 0) {
/* ln->expire < now */
switch (ln->state) {
case ND6_LLINFO_INCOMPLETE: /* 未解決 */
if (ln->asked < ND6_MAX_MCAST_QUERY) {
/*
* マルチキャストアドレス要請の再送回数以下の場合の処理
*/
ln->asked ++;
ln->expire = now + ND6_RETRANS_TIME; /* 近隣探索送信間隔 */
nd6_ns_output(ifp, &in6_addr_unspecified, &ln->addr, ln, false);
}
else {
if (ln->hold != NULL) {
/*
* 最終的には、保留されているネットワークバッファが
* あれば、ICMP6 ERROR を自分自身に返したあと、
* ネットワークバッファを開放する。
* しかし、現在、icmp6_error の実装が不完全のため、
* ネットワークバッファの開放のみ行う。
*/
#if 0 /* 保留 */
icmp6_error(ln->hold, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADDR, 0);
#endif /* #if 0 */
syscall(rel_net_buf(ln->hold));
ln->hold = NULL;
}
nd6_free(ln);
memset((void*)ln, 0, sizeof(*ln));
}
break;
case ND6_LLINFO_REACHABLE: /* 到達可能 */
if (ln->expire) {
ln->expire = now + ND6_GCOLLECTION_TIME;
ln->state = ND6_LLINFO_STALE;
}
break;
case ND6_LLINFO_STALE: /* 到達可能性は未確認 */
if (ln->expire) {
if (ln->hold != NULL) {
syscall(rel_net_buf(ln->hold));
ln->hold = NULL;
}
nd6_free(ln);
memset((void*)ln, 0, sizeof(*ln));
}
break;
case ND6_LLINFO_DELAY: /* 到達可能性の確認待機 */
ln->asked = 1;
ln->expire = now + ND6_RETRANS_TIME; /* 近隣探索送信間隔 */
ln->state = ND6_LLINFO_PROBE;
nd6_ns_output(ifp, &ln->addr, &ln->addr, ln, false);
break;
case ND6_LLINFO_PROBE: /* 到達可能性を確認中 */
if (ln->asked < ND6_MAX_UCAST_QUERY) {
/*
* ユニキャストアドレス要請の再送回数以下の場合の処理
*/
ln->asked ++;
ln->expire += ND6_RETRANS_TIME; /* 近隣探索送信間隔 */
nd6_ns_output(ifp, &ln->addr, &ln->addr, ln, false);
}
else {
if (ln->hold != NULL) {
syscall(rel_net_buf(ln->hold));
ln->hold = NULL;
}
nd6_free(ln);
memset((void*)ln, 0, sizeof(*ln));
}
break;
}
}
}
syscall(sig_sem(SEM_ND6_CACHE));
/* ディフォルトルータ・リストの処理 */
nd6_defrtrlist_timer();
/* プレフィックス・リストの処理 */
nd6_prelist_timer();
/* ネットワークインタフェースのアドレスの処理 */
in6_ifaddr_timer(ifp);
/*
* 到達可能状態の有効時間の更新
*/
if ((int32_t)(nd6_recalc_reachtm_interval - now) < 0) {
/* nd6_recalc_reachtm_interval < now */
nd6_recalc_reachtm_interval = now + ND6_RECALC_REACHTM_INTERVAL;
nd6_reachable_time = ND6_CALC_REACH_TIME(nd6_base_reachable_time);
}
timeout((callout_func)nd6_timer, NULL, ND6_TIMER_TMO);
}
/*
* 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(struct mbuf *m, struct ip6_hdr *ip6,
struct ip6_rthdr0 *rh0)
{
int addrs, index;
struct in6_addr *nextaddr, tmpaddr;
const struct ip6aux *ip6a;
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.
*/
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
(char *)&rh0->ip6r0_len - (char *)ip6);
return (-1);
}
if ((addrs = rh0->ip6r0_len / 2) < rh0->ip6r0_segleft) {
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
(char *)&rh0->ip6r0_segleft - (char *)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)) {
p6stat[IP6_STAT_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)) {
IP6_STATINC(IP6_STAT_BADOPTIONS);
goto bad;
}
/*
* Determine the scope zone of the next hop, based on the interface
* of the current hop. [RFC4007, Section 9]
* Then disambiguate the scope zone for the next hop (if necessary).
*/
if ((ip6a = ip6_getdstifaddr(m)) == NULL)
goto bad;
if (in6_setzoneid(nextaddr, ip6a->ip6a_scope_id) != 0) {
IP6_STATINC(IP6_STAT_BADSCOPE);
goto bad;
}
/*
* Swap the IPv6 destination address and nextaddr. Forward the packet.
*/
tmpaddr = *nextaddr;
*nextaddr = ip6->ip6_dst;
in6_clearscope(nextaddr); /* XXX */
ip6->ip6_dst = tmpaddr;
#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);
}
