/*
* Check if protocol type doesn't have a further header and do IPSEC
* decryption or reject right now. Protocols with further headers get
* their IPSEC treatment within the protocol specific processing.
* Called from ip_input().
* 1 = drop packet, 0 = continue processing packet.
*/
int
ip_ipsec_input(struct mbuf *m, int nxt)
{
/*
* enforce IPsec policy checking if we are seeing last header.
* note that we do not visit this with protocols with pcb layer
* code - like udp/tcp/raw ip.
*/
if ((inetsw[ip_protox[nxt]].pr_flags & PR_LASTHDR) != 0)
return (ipsec4_in_reject(m, NULL));
return (0);
}
static int
udp_mcast_input(struct udp_mcast_arg *arg)
{
struct inpcb *inp = arg->inp;
struct inpcb *last = arg->last;
struct ip *ip = arg->ip;
struct mbuf *m = arg->m;
if (check_multicast_membership(ip, inp, m) < 0)
return ERESTART; /* caller continue */
if (last != NULL) {
struct mbuf *n;
#ifdef IPSEC
/* check AH/ESP integrity. */
if (ipsec4_in_reject_so(m, last->inp_socket))
ipsecstat.in_polvio++;
/* do not inject data to pcb */
else
#endif /*IPSEC*/
#ifdef FAST_IPSEC
/* check AH/ESP integrity. */
if (ipsec4_in_reject(m, last))
;
else
#endif /*FAST_IPSEC*/
if ((n = m_copypacket(m, M_NOWAIT)) != NULL)
udp_append(last, ip, n,
arg->iphlen + sizeof(struct udphdr),
arg->udp_in);
}
arg->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)))
return EJUSTRETURN; /* caller stop */
return 0;
}
int
udp_input(struct mbuf **mp, int *offp, int proto)
{
struct sockaddr_in udp_in = { sizeof udp_in, AF_INET };
int iphlen;
struct ip *ip;
struct udphdr *uh;
struct inpcb *inp;
struct mbuf *m;
struct mbuf *opts = NULL;
int len, off;
struct ip save_ip;
struct inpcbinfo *pcbinfo = &udbinfo[mycpuid];
off = *offp;
m = *mp;
*mp = NULL;
iphlen = off;
udp_stat.udps_ipackets++;
/*
* Strip IP options, if any; should skip this,
* make available to user, and use on returned packets,
* but we don't yet have a way to check the checksum
* with options still present.
*/
if (iphlen > sizeof(struct ip)) {
ip_stripoptions(m);
iphlen = sizeof(struct ip);
}
/*
* IP and UDP headers are together in first mbuf.
* Already checked and pulled up in ip_demux().
*/
KASSERT(m->m_len >= iphlen + sizeof(struct udphdr),
("UDP header not in one mbuf"));
ip = mtod(m, struct ip *);
uh = (struct udphdr *)((caddr_t)ip + iphlen);
/* destination port of 0 is illegal, based on RFC768. */
if (uh->uh_dport == 0)
goto bad;
/*
* Make mbuf data length reflect UDP length.
* If not enough data to reflect UDP length, drop.
*/
len = ntohs((u_short)uh->uh_ulen);
if (ip->ip_len != len) {
if (len > ip->ip_len || len < sizeof(struct udphdr)) {
udp_stat.udps_badlen++;
goto bad;
}
m_adj(m, len - ip->ip_len);
/* ip->ip_len = len; */
}
/*
* Save a copy of the IP header in case we want restore it
* for sending an ICMP error message in response.
*/
save_ip = *ip;
/*
* Checksum extended UDP header and data.
*/
if (uh->uh_sum) {
if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
uh->uh_sum = m->m_pkthdr.csum_data;
else
uh->uh_sum = in_pseudo(ip->ip_src.s_addr,
ip->ip_dst.s_addr, htonl((u_short)len +
m->m_pkthdr.csum_data + IPPROTO_UDP));
uh->uh_sum ^= 0xffff;
} else {
char b[9];
bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
bzero(((struct ipovly *)ip)->ih_x1, 9);
((struct ipovly *)ip)->ih_len = uh->uh_ulen;
uh->uh_sum = in_cksum(m, len + sizeof(struct ip));
bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
}
if (uh->uh_sum) {
udp_stat.udps_badsum++;
m_freem(m);
return(IPPROTO_DONE);
}
} else
udp_stat.udps_nosum++;
if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) {
struct inpcbhead *connhead;
struct inpcontainer *ic, *ic_marker;
struct inpcontainerhead *ichead;
struct udp_mcast_arg arg;
struct inpcb *last;
int error;
/*
* Deliver a multicast or broadcast 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 multi/broadcasts 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?)
*/
/*
* Construct sockaddr format source address.
*/
udp_in.sin_port = uh->uh_sport;
udp_in.sin_addr = ip->ip_src;
arg.udp_in = &udp_in;
/*
* Locate pcb(s) for datagram.
* (Algorithm copied from raw_intr().)
*/
last = NULL;
arg.iphlen = iphlen;
connhead = &pcbinfo->hashbase[
INP_PCBCONNHASH(ip->ip_src.s_addr, uh->uh_sport,
ip->ip_dst.s_addr, uh->uh_dport, pcbinfo->hashmask)];
LIST_FOREACH(inp, connhead, inp_hash) {
#ifdef INET6
if (!INP_ISIPV4(inp))
continue;
#endif
if (!in_hosteq(inp->inp_faddr, ip->ip_src) ||
!in_hosteq(inp->inp_laddr, ip->ip_dst) ||
inp->inp_fport != uh->uh_sport ||
inp->inp_lport != uh->uh_dport)
continue;
arg.inp = inp;
arg.last = last;
arg.ip = ip;
arg.m = m;
error = udp_mcast_input(&arg);
if (error == ERESTART)
continue;
last = arg.last;
if (error == EJUSTRETURN)
goto done;
}
ichead = &pcbinfo->wildcardhashbase[
INP_PCBWILDCARDHASH(uh->uh_dport,
pcbinfo->wildcardhashmask)];
ic_marker = in_pcbcontainer_marker(mycpuid);
GET_PCBINFO_TOKEN(pcbinfo);
LIST_INSERT_HEAD(ichead, ic_marker, ic_list);
while ((ic = LIST_NEXT(ic_marker, ic_list)) != NULL) {
LIST_REMOVE(ic_marker, ic_list);
LIST_INSERT_AFTER(ic, ic_marker, ic_list);
inp = ic->ic_inp;
if (inp->inp_flags & INP_PLACEMARKER)
continue;
#ifdef INET6
if (!INP_ISIPV4(inp))
continue;
#endif
if (inp->inp_lport != uh->uh_dport)
continue;
if (inp->inp_laddr.s_addr != INADDR_ANY &&
inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
continue;
arg.inp = inp;
arg.last = last;
arg.ip = ip;
arg.m = m;
error = udp_mcast_input(&arg);
if (error == ERESTART)
continue;
last = arg.last;
if (error == EJUSTRETURN)
break;
}
LIST_REMOVE(ic_marker, ic_list);
REL_PCBINFO_TOKEN(pcbinfo);
done:
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_noportbcast++;
goto bad;
}
#ifdef IPSEC
/* check AH/ESP integrity. */
if (ipsec4_in_reject_so(m, last->inp_socket)) {
ipsecstat.in_polvio++;
goto bad;
}
#endif /*IPSEC*/
#ifdef FAST_IPSEC
/* check AH/ESP integrity. */
if (ipsec4_in_reject(m, last))
goto bad;
#endif /*FAST_IPSEC*/
udp_append(last, ip, m, iphlen + sizeof(struct udphdr),
&udp_in);
return(IPPROTO_DONE);
}
/*
* Locate pcb for datagram.
*/
inp = in_pcblookup_pkthash(pcbinfo, ip->ip_src, uh->uh_sport,
ip->ip_dst, uh->uh_dport, TRUE, m->m_pkthdr.rcvif,
udp_reuseport_ext ? m : NULL);
if (inp == NULL) {
if (log_in_vain) {
char buf[sizeof "aaa.bbb.ccc.ddd"];
strcpy(buf, inet_ntoa(ip->ip_dst));
log(LOG_INFO,
"Connection attempt to UDP %s:%d from %s:%d\n",
buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src),
ntohs(uh->uh_sport));
}
udp_stat.udps_noport++;
if (m->m_flags & (M_BCAST | M_MCAST)) {
udp_stat.udps_noportbcast++;
goto bad;
}
if (blackhole)
goto bad;
#ifdef ICMP_BANDLIM
if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
goto bad;
#endif
*ip = save_ip;
ip->ip_len += iphlen;
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
return(IPPROTO_DONE);
}
KASSERT(INP_ISIPV4(inp), ("not inet inpcb"));
#ifdef IPSEC
if (ipsec4_in_reject_so(m, inp->inp_socket)) {
ipsecstat.in_polvio++;
goto bad;
}
#endif /*IPSEC*/
#ifdef FAST_IPSEC
if (ipsec4_in_reject(m, inp))
goto bad;
#endif /*FAST_IPSEC*/
/*
* Check the minimum TTL for socket.
*/
if (ip->ip_ttl < inp->inp_ip_minttl)
goto bad;
/*
* Construct sockaddr format source address.
* Stuff source address and datagram in user buffer.
*/
udp_in.sin_port = uh->uh_sport;
udp_in.sin_addr = ip->ip_src;
if ((inp->inp_flags & INP_CONTROLOPTS) ||
(inp->inp_socket->so_options & SO_TIMESTAMP))
ip_savecontrol(inp, &opts, ip, m);
m_adj(m, iphlen + sizeof(struct udphdr));
lwkt_gettoken(&inp->inp_socket->so_rcv.ssb_token);
if (ssb_appendaddr(&inp->inp_socket->so_rcv,
(struct sockaddr *)&udp_in, m, opts) == 0) {
lwkt_reltoken(&inp->inp_socket->so_rcv.ssb_token);
udp_stat.udps_fullsock++;
goto bad;
}
lwkt_reltoken(&inp->inp_socket->so_rcv.ssb_token);
sorwakeup(inp->inp_socket);
return(IPPROTO_DONE);
bad:
m_freem(m);
if (opts)
m_freem(opts);
return(IPPROTO_DONE);
}
/*
* Subroutine of udp_input(), which appends the provided mbuf chain to the
* passed pcb/socket. The caller must provide a sockaddr_in via udp_in that
* contains the source address. If the socket ends up being an IPv6 socket,
* udp_append() will convert to a sockaddr_in6 before passing the address
* into the socket code.
*/
static void
udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
struct sockaddr_in *udp_in)
{
struct sockaddr *append_sa;
struct socket *so;
struct mbuf *opts = 0;
#ifdef INET6
struct sockaddr_in6 udp_in6;
#endif
struct udpcb *up;
INP_LOCK_ASSERT(inp);
/*
* Engage the tunneling protocol.
*/
up = intoudpcb(inp);
if (up->u_tun_func != NULL) {
(*up->u_tun_func)(n, off, inp);
return;
}
if (n == NULL)
return;
off += sizeof(struct udphdr);
#ifdef IPSEC
/* Check AH/ESP integrity. */
if (ipsec4_in_reject(n, inp)) {
m_freem(n);
IPSECSTAT_INC(ips_in_polvio);
return;
}
#ifdef IPSEC_NAT_T
up = intoudpcb(inp);
KASSERT(up != NULL, ("%s: udpcb NULL", __func__));
if (up->u_flags & UF_ESPINUDP_ALL) { /* IPSec UDP encaps. */
n = udp4_espdecap(inp, n, off);
if (n == NULL) /* Consumed. */
return;
}
#endif /* IPSEC_NAT_T */
#endif /* IPSEC */
#ifdef MAC
if (mac_inpcb_check_deliver(inp, n) != 0) {
m_freem(n);
return;
}
#endif /* MAC */
if (inp->inp_flags & INP_CONTROLOPTS ||
inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
#ifdef INET6
if (inp->inp_vflag & INP_IPV6)
(void)ip6_savecontrol_v4(inp, n, &opts, NULL);
else
#endif /* INET6 */
ip_savecontrol(inp, &opts, ip, n);
}
#ifdef INET6
if (inp->inp_vflag & INP_IPV6) {
bzero(&udp_in6, sizeof(udp_in6));
udp_in6.sin6_len = sizeof(udp_in6);
udp_in6.sin6_family = AF_INET6;
in6_sin_2_v4mapsin6(udp_in, &udp_in6);
append_sa = (struct sockaddr *)&udp_in6;
} else
#endif /* INET6 */
append_sa = (struct sockaddr *)udp_in;
m_adj(n, off);
so = inp->inp_socket;
SOCKBUF_LOCK(&so->so_rcv);
if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
SOCKBUF_UNLOCK(&so->so_rcv);
m_freem(n);
if (opts)
m_freem(opts);
UDPSTAT_INC(udps_fullsock);
} else
sorwakeup_locked(so);
}
/*
* Check if this packet has an active SA and needs to be dropped instead
* of forwarded.
* Called from ip_forward().
* 1 = drop packet, 0 = forward packet.
*/
int
ip_ipsec_fwd(struct mbuf *m)
{
return (ipsec4_in_reject(m, NULL));
}
