Index: head/sys/netinet/udp_usrreq.c
===================================================================
--- head/sys/netinet/udp_usrreq.c	(revision 339326)
+++ head/sys/netinet/udp_usrreq.c	(revision 339327)
@@ -1,1817 +1,1818 @@
 /*-
  * SPDX-License-Identifier: BSD-3-Clause
  *
  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
  *	The Regents of the University of California.
  * Copyright (c) 2008 Robert N. M. Watson
  * Copyright (c) 2010-2011 Juniper Networks, Inc.
  * Copyright (c) 2014 Kevin Lo
  * All rights reserved.
  *
  * Portions of this software were developed by Robert N. M. Watson under
  * contract to Juniper Networks, Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  *	@(#)udp_usrreq.c	8.6 (Berkeley) 5/23/95
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
 #include "opt_inet.h"
 #include "opt_inet6.h"
 #include "opt_ipsec.h"
 #include "opt_rss.h"
 
 #include <sys/param.h>
 #include <sys/domain.h>
 #include <sys/eventhandler.h>
 #include <sys/jail.h>
 #include <sys/kernel.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
 #include <sys/mbuf.h>
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/protosw.h>
 #include <sys/sdt.h>
 #include <sys/signalvar.h>
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/sx.h>
 #include <sys/sysctl.h>
 #include <sys/syslog.h>
 #include <sys/systm.h>
 
 #include <vm/uma.h>
 
 #include <net/if.h>
 #include <net/if_var.h>
 #include <net/route.h>
 #include <net/rss_config.h>
 
 #include <netinet/in.h>
 #include <netinet/in_kdtrace.h>
 #include <netinet/in_pcb.h>
 #include <netinet/in_systm.h>
 #include <netinet/in_var.h>
 #include <netinet/ip.h>
 #ifdef INET6
 #include <netinet/ip6.h>
 #endif
 #include <netinet/ip_icmp.h>
 #include <netinet/icmp_var.h>
 #include <netinet/ip_var.h>
 #include <netinet/ip_options.h>
 #ifdef INET6
 #include <netinet6/ip6_var.h>
 #endif
 #include <netinet/udp.h>
 #include <netinet/udp_var.h>
 #include <netinet/udplite.h>
 #include <netinet/in_rss.h>
 
 #include <netipsec/ipsec_support.h>
 
 #include <machine/in_cksum.h>
 
 #include <security/mac/mac_framework.h>
 
 /*
  * UDP and UDP-Lite protocols implementation.
  * Per RFC 768, August, 1980.
  * Per RFC 3828, July, 2004.
  */
 
 /*
  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
  * removes the only data integrity mechanism for packets and malformed
  * packets that would otherwise be discarded due to bad checksums, and may
  * cause problems (especially for NFS data blocks).
  */
 VNET_DEFINE(int, udp_cksum) = 1;
 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
 
 int	udp_log_in_vain = 0;
 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
     &udp_log_in_vain, 0, "Log all incoming UDP packets");
 
 VNET_DEFINE(int, udp_blackhole) = 0;
 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
     &VNET_NAME(udp_blackhole), 0,
     "Do not send port unreachables for refused connects");
 
 u_long	udp_sendspace = 9216;		/* really max datagram size */
 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
 
 u_long	udp_recvspace = 40 * (1024 +
 #ifdef INET6
 				      sizeof(struct sockaddr_in6)
 #else
 				      sizeof(struct sockaddr_in)
 #endif
 				      );	/* 40 1K datagrams */
 
 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
 
 VNET_DEFINE(struct inpcbhead, udb);		/* from udp_var.h */
 VNET_DEFINE(struct inpcbinfo, udbinfo);
 VNET_DEFINE(struct inpcbhead, ulitecb);
 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
 VNET_DEFINE_STATIC(uma_zone_t, udpcb_zone);
 #define	V_udpcb_zone			VNET(udpcb_zone)
 
 #ifndef UDBHASHSIZE
 #define	UDBHASHSIZE	128
 #endif
 
 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);		/* from udp_var.h */
 VNET_PCPUSTAT_SYSINIT(udpstat);
 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
 
 #ifdef VIMAGE
 VNET_PCPUSTAT_SYSUNINIT(udpstat);
 #endif /* VIMAGE */
 #ifdef INET
 static void	udp_detach(struct socket *so);
 static int	udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
 		    struct mbuf *, struct thread *);
 #endif
 
 static void
 udp_zone_change(void *tag)
 {
 
 	uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
 	uma_zone_set_max(V_udpcb_zone, maxsockets);
 }
 
 static int
 udp_inpcb_init(void *mem, int size, int flags)
 {
 	struct inpcb *inp;
 
 	inp = mem;
 	INP_LOCK_INIT(inp, "inp", "udpinp");
 	return (0);
 }
 
 static int
 udplite_inpcb_init(void *mem, int size, int flags)
 {
 	struct inpcb *inp;
 
 	inp = mem;
 	INP_LOCK_INIT(inp, "inp", "udpliteinp");
 	return (0);
 }
 
 void
 udp_init(void)
 {
 
 	/*
 	 * For now default to 2-tuple UDP hashing - until the fragment
 	 * reassembly code can also update the flowid.
 	 *
 	 * Once we can calculate the flowid that way and re-establish
 	 * a 4-tuple, flip this to 4-tuple.
 	 */
 	in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE,
 	    "udp_inpcb", udp_inpcb_init, IPI_HASHFIELDS_2TUPLE);
 	V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb),
 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
 	uma_zone_set_max(V_udpcb_zone, maxsockets);
 	uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached");
 	EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
 	    EVENTHANDLER_PRI_ANY);
 }
 
 void
 udplite_init(void)
 {
 
 	in_pcbinfo_init(&V_ulitecbinfo, "udplite", &V_ulitecb, UDBHASHSIZE,
 	    UDBHASHSIZE, "udplite_inpcb", udplite_inpcb_init,
 	    IPI_HASHFIELDS_2TUPLE);
 }
 
 /*
  * Kernel module interface for updating udpstat.  The argument is an index
  * into udpstat treated as an array of u_long.  While this encodes the
  * general layout of udpstat into the caller, it doesn't encode its location,
  * so that future changes to add, for example, per-CPU stats support won't
  * cause binary compatibility problems for kernel modules.
  */
 void
 kmod_udpstat_inc(int statnum)
 {
 
 	counter_u64_add(VNET(udpstat)[statnum], 1);
 }
 
 int
 udp_newudpcb(struct inpcb *inp)
 {
 	struct udpcb *up;
 
 	up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO);
 	if (up == NULL)
 		return (ENOBUFS);
 	inp->inp_ppcb = up;
 	return (0);
 }
 
 void
 udp_discardcb(struct udpcb *up)
 {
 
 	uma_zfree(V_udpcb_zone, up);
 }
 
 #ifdef VIMAGE
 static void
 udp_destroy(void *unused __unused)
 {
 
 	in_pcbinfo_destroy(&V_udbinfo);
 	uma_zdestroy(V_udpcb_zone);
 }
 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
 
 static void
 udplite_destroy(void *unused __unused)
 {
 
 	in_pcbinfo_destroy(&V_ulitecbinfo);
 }
 VNET_SYSUNINIT(udplite, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udplite_destroy,
     NULL);
 #endif
 
 #ifdef INET
 /*
  * 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.
  *
  * In the normal case udp_append() will return 0, indicating that you
  * must unlock the inp. However if a tunneling protocol is in place we increment
  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
  * then decrement the reference count. If the inp_rele returns 1, indicating the
  * inp is gone, we return that to the caller to tell them *not* to unlock
  * the inp. In the case of multi-cast this will cause the distribution
  * to stop (though most tunneling protocols known currently do *not* use
  * multicast).
  */
 static int
 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 *tmpopts, *opts = NULL;
 #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) {
 		in_pcbref(inp);
 		INP_RUNLOCK(inp);
 		(*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
 		    up->u_tun_ctx);
 		INP_RLOCK(inp);
 		return (in_pcbrele_rlocked(inp));
 	}
 
 	off += sizeof(struct udphdr);
 
 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 	/* Check AH/ESP integrity. */
 	if (IPSEC_ENABLED(ipv4) &&
 	    IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
 		m_freem(n);
 		return (0);
 	}
 	if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
 		if (IPSEC_ENABLED(ipv4) &&
 		    UDPENCAP_INPUT(n, off, AF_INET) != 0)
 			return (0);	/* Consumed. */
 	}
 #endif /* IPSEC */
 #ifdef MAC
 	if (mac_inpcb_check_deliver(inp, n) != 0) {
 		m_freem(n);
 		return (0);
 	}
 #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);
 	}
 	if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
 		tmpopts = sbcreatecontrol((caddr_t)&udp_in[1],
 			sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP);
 		if (tmpopts) {
 			if (opts) {
 				tmpopts->m_next = opts;
 				opts = tmpopts;
 			} else
 				opts = tmpopts;
 		}
 	}
 #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[0], &udp_in6);
 		append_sa = (struct sockaddr *)&udp_in6;
 	} else
 #endif /* INET6 */
 		append_sa = (struct sockaddr *)&udp_in[0];
 	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);
 	return (0);
 }
 
 int
 udp_input(struct mbuf **mp, int *offp, int proto)
 {
 	struct ip *ip;
 	struct udphdr *uh;
 	struct ifnet *ifp;
 	struct inpcb *inp;
 	uint16_t len, ip_len;
 	struct inpcbinfo *pcbinfo;
 	struct ip save_ip;
 	struct sockaddr_in udp_in[2];
 	struct mbuf *m;
 	struct m_tag *fwd_tag;
 	struct epoch_tracker et;
 	int cscov_partial, iphlen;
 
 	m = *mp;
 	iphlen = *offp;
 	ifp = m->m_pkthdr.rcvif;
 	*mp = NULL;
 	UDPSTAT_INC(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);
 	}
 
 	/*
 	 * Get IP and UDP header together in first mbuf.
 	 */
 	ip = mtod(m, struct ip *);
 	if (m->m_len < iphlen + sizeof(struct udphdr)) {
 		if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 			UDPSTAT_INC(udps_hdrops);
 			return (IPPROTO_DONE);
 		}
 		ip = mtod(m, struct ip *);
 	}
 	uh = (struct udphdr *)((caddr_t)ip + iphlen);
 	cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 
 	/*
 	 * Destination port of 0 is illegal, based on RFC768.
 	 */
 	if (uh->uh_dport == 0)
 		goto badunlocked;
 
 	/*
 	 * Construct sockaddr format source address.  Stuff source address
 	 * and datagram in user buffer.
 	 */
 	bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 	udp_in[0].sin_len = sizeof(struct sockaddr_in);
 	udp_in[0].sin_family = AF_INET;
 	udp_in[0].sin_port = uh->uh_sport;
 	udp_in[0].sin_addr = ip->ip_src;
 	udp_in[1].sin_len = sizeof(struct sockaddr_in);
 	udp_in[1].sin_family = AF_INET;
 	udp_in[1].sin_port = uh->uh_dport;
 	udp_in[1].sin_addr = ip->ip_dst;
 
 	/*
 	 * Make mbuf data length reflect UDP length.  If not enough data to
 	 * reflect UDP length, drop.
 	 */
 	len = ntohs((u_short)uh->uh_ulen);
 	ip_len = ntohs(ip->ip_len) - iphlen;
 	if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 		/* Zero means checksum over the complete packet. */
 		if (len == 0)
 			len = ip_len;
 		cscov_partial = 0;
 	}
 	if (ip_len != len) {
 		if (len > ip_len || len < sizeof(struct udphdr)) {
 			UDPSTAT_INC(udps_badlen);
 			goto badunlocked;
 		}
 		if (proto == IPPROTO_UDP)
 			m_adj(m, len - ip_len);
 	}
 
 	/*
 	 * Save a copy of the IP header in case we want restore it for
 	 * sending an ICMP error message in response.
 	 */
 	if (!V_udp_blackhole)
 		save_ip = *ip;
 	else
 		memset(&save_ip, 0, sizeof(save_ip));
 
 	/*
 	 * Checksum extended UDP header and data.
 	 */
 	if (uh->uh_sum) {
 		u_short uh_sum;
 
 		if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 		    !cscov_partial) {
 			if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 				uh_sum = m->m_pkthdr.csum_data;
 			else
 				uh_sum = in_pseudo(ip->ip_src.s_addr,
 				    ip->ip_dst.s_addr, htonl((u_short)len +
 				    m->m_pkthdr.csum_data + proto));
 			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 = (proto == IPPROTO_UDP) ?
 			    uh->uh_ulen : htons(ip_len);
 			uh_sum = in_cksum(m, len + sizeof (struct ip));
 			bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
 		}
 		if (uh_sum) {
 			UDPSTAT_INC(udps_badsum);
 			m_freem(m);
 			return (IPPROTO_DONE);
 		}
 	} else {
 		if (proto == IPPROTO_UDP) {
 			UDPSTAT_INC(udps_nosum);
 		} else {
 			/* UDPLite requires a checksum */
 			/* XXX: What is the right UDPLite MIB counter here? */
 			m_freem(m);
 			return (IPPROTO_DONE);
 		}
 	}
 
 	pcbinfo = udp_get_inpcbinfo(proto);
 	if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 	    in_broadcast(ip->ip_dst, ifp)) {
 		struct inpcb *last;
 		struct inpcbhead *pcblist;
-		struct ip_moptions *imo;
 
 		INP_INFO_RLOCK_ET(pcbinfo, et);
 		pcblist = udp_get_pcblist(proto);
 		last = NULL;
 		CK_LIST_FOREACH(inp, pcblist, inp_list) {
 			if (inp->inp_lport != uh->uh_dport)
 				continue;
 #ifdef INET6
 			if ((inp->inp_vflag & INP_IPV4) == 0)
 				continue;
 #endif
 			if (inp->inp_laddr.s_addr != INADDR_ANY &&
 			    inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 				continue;
 			if (inp->inp_faddr.s_addr != INADDR_ANY &&
 			    inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 				continue;
 			if (inp->inp_fport != 0 &&
 			    inp->inp_fport != uh->uh_sport)
 				continue;
 
 			INP_RLOCK(inp);
 
 			/*
 			 * 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 held.
 			 */
 
 			/*
 			 * Handle socket delivery policy for any-source
 			 * and source-specific multicast. [RFC3678]
 			 */
-			imo = inp->inp_moptions;
 			if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
+				struct ip_moptions	*imo;
 				struct sockaddr_in	 group;
 				int			 blocked;
+
+				imo = inp->inp_moptions;
 				if (imo == NULL) {
 					INP_RUNLOCK(inp);
 					continue;
 				}
 				bzero(&group, sizeof(struct sockaddr_in));
 				group.sin_len = sizeof(struct sockaddr_in);
 				group.sin_family = AF_INET;
 				group.sin_addr = ip->ip_dst;
 
 				blocked = imo_multi_filter(imo, ifp,
 					(struct sockaddr *)&group,
 					(struct sockaddr *)&udp_in[0]);
 				if (blocked != MCAST_PASS) {
 					if (blocked == MCAST_NOTGMEMBER)
 						IPSTAT_INC(ips_notmember);
 					if (blocked == MCAST_NOTSMEMBER ||
 					    blocked == MCAST_MUTED)
 						UDPSTAT_INC(udps_filtermcast);
 					INP_RUNLOCK(inp);
 					continue;
 				}
 			}
 			if (last != NULL) {
 				struct mbuf *n;
 
 				if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
 				    NULL) {
 					if (proto == IPPROTO_UDPLITE)
 						UDPLITE_PROBE(receive, NULL, last, ip,
 						    last, uh);
 					else
 						UDP_PROBE(receive, NULL, last, ip, last,
 						    uh);
 					if (udp_append(last, ip, n, iphlen,
 						udp_in)) {
 						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_REUSEPORT_LB|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_noportbcast);
 			if (inp)
 				INP_RUNLOCK(inp);
 			INP_INFO_RUNLOCK_ET(pcbinfo, et);
 			goto badunlocked;
 		}
 		if (proto == IPPROTO_UDPLITE)
 			UDPLITE_PROBE(receive, NULL, last, ip, last, uh);
 		else
 			UDP_PROBE(receive, NULL, last, ip, last, uh);
 		if (udp_append(last, ip, m, iphlen, udp_in) == 0) 
 			INP_RUNLOCK(last);
 	inp_lost:
 		INP_INFO_RUNLOCK_ET(pcbinfo, et);
 		return (IPPROTO_DONE);
 	}
 
 	/*
 	 * Locate pcb for datagram.
 	 */
 
 	/*
 	 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 	 */
 	if ((m->m_flags & M_IP_NEXTHOP) &&
 	    (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 		struct sockaddr_in *next_hop;
 
 		next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 
 		/*
 		 * Transparently forwarded. Pretend to be the destination.
 		 * Already got one like this?
 		 */
 		inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 		    ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, 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 = in_pcblookup(pcbinfo, ip->ip_src,
 			    uh->uh_sport, next_hop->sin_addr,
 			    next_hop->sin_port ? htons(next_hop->sin_port) :
 			    uh->uh_dport, INPLOOKUP_WILDCARD |
 			    INPLOOKUP_RLOCKPCB, ifp);
 		}
 		/* Remove the tag from the packet. We don't need it anymore. */
 		m_tag_delete(m, fwd_tag);
 		m->m_flags &= ~M_IP_NEXTHOP;
 	} else
 		inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 		    ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 		    INPLOOKUP_RLOCKPCB, ifp, m);
 	if (inp == NULL) {
 		if (udp_log_in_vain) {
 			char src[INET_ADDRSTRLEN];
 			char dst[INET_ADDRSTRLEN];
 
 			log(LOG_INFO,
 			    "Connection attempt to UDP %s:%d from %s:%d\n",
 			    inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 			    inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 		}
 		if (proto == IPPROTO_UDPLITE)
 			UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
 		else
 			UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
 		UDPSTAT_INC(udps_noport);
 		if (m->m_flags & (M_BCAST | M_MCAST)) {
 			UDPSTAT_INC(udps_noportbcast);
 			goto badunlocked;
 		}
 		if (V_udp_blackhole)
 			goto badunlocked;
 		if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 			goto badunlocked;
 		*ip = save_ip;
 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 		return (IPPROTO_DONE);
 	}
 
 	/*
 	 * Check the minimum TTL for socket.
 	 */
 	INP_RLOCK_ASSERT(inp);
 	if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 		if (proto == IPPROTO_UDPLITE)
 			UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 		else
 			UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 		INP_RUNLOCK(inp);
 		m_freem(m);
 		return (IPPROTO_DONE);
 	}
 	if (cscov_partial) {
 		struct udpcb *up;
 
 		up = intoudpcb(inp);
 		if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 			INP_RUNLOCK(inp);
 			m_freem(m);
 			return (IPPROTO_DONE);
 		}
 	}
 
 	if (proto == IPPROTO_UDPLITE)
 		UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 	else
 		UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 	if (udp_append(inp, ip, m, iphlen, udp_in) == 0) 
 		INP_RUNLOCK(inp);
 	return (IPPROTO_DONE);
 
 badunlocked:
 	m_freem(m);
 	return (IPPROTO_DONE);
 }
 #endif /* INET */
 
 /*
  * Notify a udp user of an asynchronous error; just wake up so that they can
  * collect error status.
  */
 struct inpcb *
 udp_notify(struct inpcb *inp, int errno)
 {
 
 	INP_WLOCK_ASSERT(inp);
 	if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 	     errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
 		RTFREE(inp->inp_route.ro_rt);
 		inp->inp_route.ro_rt = (struct rtentry *)NULL;
 	}
 
 	inp->inp_socket->so_error = errno;
 	sorwakeup(inp->inp_socket);
 	sowwakeup(inp->inp_socket);
 	return (inp);
 }
 
 #ifdef INET
 static void
 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
     struct inpcbinfo *pcbinfo)
 {
 	struct ip *ip = vip;
 	struct udphdr *uh;
 	struct in_addr faddr;
 	struct inpcb *inp;
 
 	faddr = ((struct sockaddr_in *)sa)->sin_addr;
 	if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 		return;
 
 	if (PRC_IS_REDIRECT(cmd)) {
 		/* signal EHOSTDOWN, as it flushes the cached route */
 		in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
 		return;
 	}
 
 	/*
 	 * Hostdead is ugly because it goes linearly through all PCBs.
 	 *
 	 * XXX: We never get this from ICMP, otherwise it makes an excellent
 	 * DoS attack on machines with many connections.
 	 */
 	if (cmd == PRC_HOSTDEAD)
 		ip = NULL;
 	else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
 		return;
 	if (ip != NULL) {
 		uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 		inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 		    ip->ip_src, uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
 		if (inp != NULL) {
 			INP_WLOCK_ASSERT(inp);
 			if (inp->inp_socket != NULL) {
 				udp_notify(inp, inetctlerrmap[cmd]);
 			}
 			INP_WUNLOCK(inp);
 		} else {
 			inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 					   ip->ip_src, uh->uh_sport,
 					   INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 			if (inp != NULL) {
 				struct udpcb *up;
 				void *ctx;
 				udp_tun_icmp_t func;
 
 				up = intoudpcb(inp);
 				ctx = up->u_tun_ctx;
 				func = up->u_icmp_func;
 				INP_RUNLOCK(inp);
 				if (func != NULL)
 					(*func)(cmd, sa, vip, ctx);
 			}
 		}
 	} else
 		in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd],
 		    udp_notify);
 }
 void
 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 {
 
 	return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo));
 }
 
 void
 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 {
 
 	return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo));
 }
 #endif /* INET */
 
 static int
 udp_pcblist(SYSCTL_HANDLER_ARGS)
 {
 	int error, i, n;
 	struct inpcb *inp, **inp_list;
 	inp_gen_t gencnt;
 	struct xinpgen xig;
 	struct epoch_tracker et;
 
 	/*
 	 * The process of preparing the PCB list is too time-consuming and
 	 * resource-intensive to repeat twice on every request.
 	 */
 	if (req->oldptr == 0) {
 		n = V_udbinfo.ipi_count;
 		n += imax(n / 8, 10);
 		req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 		return (0);
 	}
 
 	if (req->newptr != 0)
 		return (EPERM);
 
 	/*
 	 * OK, now we're committed to doing something.
 	 */
 	INP_INFO_RLOCK_ET(&V_udbinfo, et);
 	gencnt = V_udbinfo.ipi_gencnt;
 	n = V_udbinfo.ipi_count;
 	INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 
 	error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
 		+ n * sizeof(struct xinpcb));
 	if (error != 0)
 		return (error);
 
 	xig.xig_len = sizeof xig;
 	xig.xig_count = n;
 	xig.xig_gen = gencnt;
 	xig.xig_sogen = so_gencnt;
 	error = SYSCTL_OUT(req, &xig, sizeof xig);
 	if (error)
 		return (error);
 
 	inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
 	if (inp_list == NULL)
 		return (ENOMEM);
 
 	INP_INFO_RLOCK_ET(&V_udbinfo, et);
 	for (inp = CK_LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
 	     inp = CK_LIST_NEXT(inp, inp_list)) {
 		INP_WLOCK(inp);
 		if (inp->inp_gencnt <= gencnt &&
 		    cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 			in_pcbref(inp);
 			inp_list[i++] = inp;
 		}
 		INP_WUNLOCK(inp);
 	}
 	INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 	n = i;
 
 	error = 0;
 	for (i = 0; i < n; i++) {
 		inp = inp_list[i];
 		INP_RLOCK(inp);
 		if (inp->inp_gencnt <= gencnt) {
 			struct xinpcb xi;
 
 			in_pcbtoxinpcb(inp, &xi);
 			INP_RUNLOCK(inp);
 			error = SYSCTL_OUT(req, &xi, sizeof xi);
 		} else
 			INP_RUNLOCK(inp);
 	}
 	INP_INFO_WLOCK(&V_udbinfo);
 	for (i = 0; i < n; i++) {
 		inp = inp_list[i];
 		INP_RLOCK(inp);
 		if (!in_pcbrele_rlocked(inp))
 			INP_RUNLOCK(inp);
 	}
 	INP_INFO_WUNLOCK(&V_udbinfo);
 
 	if (!error) {
 		/*
 		 * Give the user an updated idea of our state.  If the
 		 * generation differs from what we told her before, she knows
 		 * that something happened while we were processing this
 		 * request, and it might be necessary to retry.
 		 */
 		INP_INFO_RLOCK_ET(&V_udbinfo, et);
 		xig.xig_gen = V_udbinfo.ipi_gencnt;
 		xig.xig_sogen = so_gencnt;
 		xig.xig_count = V_udbinfo.ipi_count;
 		INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 		error = SYSCTL_OUT(req, &xig, sizeof xig);
 	}
 	free(inp_list, M_TEMP);
 	return (error);
 }
 
 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
     CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
 
 #ifdef INET
 static int
 udp_getcred(SYSCTL_HANDLER_ARGS)
 {
 	struct xucred xuc;
 	struct sockaddr_in addrs[2];
 	struct inpcb *inp;
 	int error;
 
 	error = priv_check(req->td, PRIV_NETINET_GETCRED);
 	if (error)
 		return (error);
 	error = SYSCTL_IN(req, addrs, sizeof(addrs));
 	if (error)
 		return (error);
 	inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 	    addrs[0].sin_addr, addrs[0].sin_port,
 	    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 	if (inp != NULL) {
 		INP_RLOCK_ASSERT(inp);
 		if (inp->inp_socket == NULL)
 			error = ENOENT;
 		if (error == 0)
 			error = cr_canseeinpcb(req->td->td_ucred, inp);
 		if (error == 0)
 			cru2x(inp->inp_cred, &xuc);
 		INP_RUNLOCK(inp);
 	} else
 		error = ENOENT;
 	if (error == 0)
 		error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 	return (error);
 }
 
 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
 #endif /* INET */
 
 int
 udp_ctloutput(struct socket *so, struct sockopt *sopt)
 {
 	struct inpcb *inp;
 	struct udpcb *up;
 	int isudplite, error, optval;
 
 	error = 0;
 	isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 	INP_WLOCK(inp);
 	if (sopt->sopt_level != so->so_proto->pr_protocol) {
 #ifdef INET6
 		if (INP_CHECK_SOCKAF(so, AF_INET6)) {
 			INP_WUNLOCK(inp);
 			error = ip6_ctloutput(so, sopt);
 		}
 #endif
 #if defined(INET) && defined(INET6)
 		else
 #endif
 #ifdef INET
 		{
 			INP_WUNLOCK(inp);
 			error = ip_ctloutput(so, sopt);
 		}
 #endif
 		return (error);
 	}
 
 	switch (sopt->sopt_dir) {
 	case SOPT_SET:
 		switch (sopt->sopt_name) {
 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 #ifdef INET
 		case UDP_ENCAP:
 			if (!IPSEC_ENABLED(ipv4)) {
 				INP_WUNLOCK(inp);
 				return (ENOPROTOOPT);
 			}
 			error = UDPENCAP_PCBCTL(inp, sopt);
 			break;
 #endif /* INET */
 #endif /* IPSEC */
 		case UDPLITE_SEND_CSCOV:
 		case UDPLITE_RECV_CSCOV:
 			if (!isudplite) {
 				INP_WUNLOCK(inp);
 				error = ENOPROTOOPT;
 				break;
 			}
 			INP_WUNLOCK(inp);
 			error = sooptcopyin(sopt, &optval, sizeof(optval),
 			    sizeof(optval));
 			if (error != 0)
 				break;
 			inp = sotoinpcb(so);
 			KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 			INP_WLOCK(inp);
 			up = intoudpcb(inp);
 			KASSERT(up != NULL, ("%s: up == NULL", __func__));
 			if ((optval != 0 && optval < 8) || (optval > 65535)) {
 				INP_WUNLOCK(inp);
 				error = EINVAL;
 				break;
 			}
 			if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
 				up->u_txcslen = optval;
 			else
 				up->u_rxcslen = optval;
 			INP_WUNLOCK(inp);
 			break;
 		default:
 			INP_WUNLOCK(inp);
 			error = ENOPROTOOPT;
 			break;
 		}
 		break;
 	case SOPT_GET:
 		switch (sopt->sopt_name) {
 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 #ifdef INET
 		case UDP_ENCAP:
 			if (!IPSEC_ENABLED(ipv4)) {
 				INP_WUNLOCK(inp);
 				return (ENOPROTOOPT);
 			}
 			error = UDPENCAP_PCBCTL(inp, sopt);
 			break;
 #endif /* INET */
 #endif /* IPSEC */
 		case UDPLITE_SEND_CSCOV:
 		case UDPLITE_RECV_CSCOV:
 			if (!isudplite) {
 				INP_WUNLOCK(inp);
 				error = ENOPROTOOPT;
 				break;
 			}
 			up = intoudpcb(inp);
 			KASSERT(up != NULL, ("%s: up == NULL", __func__));
 			if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
 				optval = up->u_txcslen;
 			else
 				optval = up->u_rxcslen;
 			INP_WUNLOCK(inp);
 			error = sooptcopyout(sopt, &optval, sizeof(optval));
 			break;
 		default:
 			INP_WUNLOCK(inp);
 			error = ENOPROTOOPT;
 			break;
 		}
 		break;
 	}	
 	return (error);
 }
 
 #ifdef INET
 #define	UH_WLOCKED	2
 #define	UH_RLOCKED	1
 #define	UH_UNLOCKED	0
 static int
 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
     struct mbuf *control, struct thread *td)
 {
 	struct udpiphdr *ui;
 	int len = m->m_pkthdr.len;
 	struct in_addr faddr, laddr;
 	struct cmsghdr *cm;
 	struct inpcbinfo *pcbinfo;
 	struct sockaddr_in *sin, src;
 	struct epoch_tracker et;
 	int cscov_partial = 0;
 	int error = 0;
 	int ipflags;
 	u_short fport, lport;
 	int unlock_udbinfo, unlock_inp;
 	u_char tos;
 	uint8_t pr;
 	uint16_t cscov = 0;
 	uint32_t flowid = 0;
 	uint8_t flowtype = M_HASHTYPE_NONE;
 
 	/*
 	 * udp_output() may need to temporarily bind or connect the current
 	 * inpcb.  As such, we don't know up front whether we will need the
 	 * pcbinfo lock or not.  Do any work to decide what is needed up
 	 * front before acquiring any locks.
 	 */
 	if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
 		if (control)
 			m_freem(control);
 		m_freem(m);
 		return (EMSGSIZE);
 	}
 
 	src.sin_family = 0;
 	sin = (struct sockaddr_in *)addr;
 	if (sin == NULL ||
 	    (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
 		INP_WLOCK(inp);
 		unlock_inp = UH_WLOCKED;
 	} else {
 		INP_RLOCK(inp);
 		unlock_inp = UH_RLOCKED;
 	}
 	tos = inp->inp_ip_tos;
 	if (control != NULL) {
 		/*
 		 * XXX: Currently, we assume all the optional information is
 		 * stored in a single mbuf.
 		 */
 		if (control->m_next) {
 			if (unlock_inp == UH_WLOCKED)
 				INP_WUNLOCK(inp);
 			else
 				INP_RUNLOCK(inp);
 			m_freem(control);
 			m_freem(m);
 			return (EINVAL);
 		}
 		for (; control->m_len > 0;
 		    control->m_data += CMSG_ALIGN(cm->cmsg_len),
 		    control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
 			cm = mtod(control, struct cmsghdr *);
 			if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
 			    || cm->cmsg_len > control->m_len) {
 				error = EINVAL;
 				break;
 			}
 			if (cm->cmsg_level != IPPROTO_IP)
 				continue;
 
 			switch (cm->cmsg_type) {
 			case IP_SENDSRCADDR:
 				if (cm->cmsg_len !=
 				    CMSG_LEN(sizeof(struct in_addr))) {
 					error = EINVAL;
 					break;
 				}
 				bzero(&src, sizeof(src));
 				src.sin_family = AF_INET;
 				src.sin_len = sizeof(src);
 				src.sin_port = inp->inp_lport;
 				src.sin_addr =
 				    *(struct in_addr *)CMSG_DATA(cm);
 				break;
 
 			case IP_TOS:
 				if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
 					error = EINVAL;
 					break;
 				}
 				tos = *(u_char *)CMSG_DATA(cm);
 				break;
 
 			case IP_FLOWID:
 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
 					error = EINVAL;
 					break;
 				}
 				flowid = *(uint32_t *) CMSG_DATA(cm);
 				break;
 
 			case IP_FLOWTYPE:
 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
 					error = EINVAL;
 					break;
 				}
 				flowtype = *(uint32_t *) CMSG_DATA(cm);
 				break;
 
 #ifdef	RSS
 			case IP_RSSBUCKETID:
 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
 					error = EINVAL;
 					break;
 				}
 				/* This is just a placeholder for now */
 				break;
 #endif	/* RSS */
 			default:
 				error = ENOPROTOOPT;
 				break;
 			}
 			if (error)
 				break;
 		}
 		m_freem(control);
 	}
 	if (error) {
 		if (unlock_inp == UH_WLOCKED)
 			INP_WUNLOCK(inp);
 		else
 			INP_RUNLOCK(inp);
 		m_freem(m);
 		return (error);
 	}
 
 	/*
 	 * Depending on whether or not the application has bound or connected
 	 * the socket, we may have to do varying levels of work.  The optimal
 	 * case is for a connected UDP socket, as a global lock isn't
 	 * required at all.
 	 *
 	 * In order to decide which we need, we require stability of the
 	 * inpcb binding, which we ensure by acquiring a read lock on the
 	 * inpcb.  This doesn't strictly follow the lock order, so we play
 	 * the trylock and retry game; note that we may end up with more
 	 * conservative locks than required the second time around, so later
 	 * assertions have to accept that.  Further analysis of the number of
 	 * misses under contention is required.
 	 *
 	 * XXXRW: Check that hash locking update here is correct.
 	 */
 	pr = inp->inp_socket->so_proto->pr_protocol;
 	pcbinfo = udp_get_inpcbinfo(pr);
 	sin = (struct sockaddr_in *)addr;
 	if (sin != NULL &&
 	    (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
 		INP_HASH_WLOCK(pcbinfo);
 		unlock_udbinfo = UH_WLOCKED;
 	} else if ((sin != NULL && (
 	    (sin->sin_addr.s_addr == INADDR_ANY) ||
 	    (sin->sin_addr.s_addr == INADDR_BROADCAST) ||
 	    (inp->inp_laddr.s_addr == INADDR_ANY) ||
 	    (inp->inp_lport == 0))) ||
 	    (src.sin_family == AF_INET)) {
 		INP_HASH_RLOCK_ET(pcbinfo, et);
 		unlock_udbinfo = UH_RLOCKED;
 	} else
 		unlock_udbinfo = UH_UNLOCKED;
 
 	/*
 	 * If the IP_SENDSRCADDR control message was specified, override the
 	 * source address for this datagram.  Its use is invalidated if the
 	 * address thus specified is incomplete or clobbers other inpcbs.
 	 */
 	laddr = inp->inp_laddr;
 	lport = inp->inp_lport;
 	if (src.sin_family == AF_INET) {
 		INP_HASH_LOCK_ASSERT(pcbinfo);
 		if ((lport == 0) ||
 		    (laddr.s_addr == INADDR_ANY &&
 		     src.sin_addr.s_addr == INADDR_ANY)) {
 			error = EINVAL;
 			goto release;
 		}
 		error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
 		    &laddr.s_addr, &lport, td->td_ucred);
 		if (error)
 			goto release;
 	}
 
 	/*
 	 * If a UDP socket has been connected, then a local address/port will
 	 * have been selected and bound.
 	 *
 	 * If a UDP socket has not been connected to, then an explicit
 	 * destination address must be used, in which case a local
 	 * address/port may not have been selected and bound.
 	 */
 	if (sin != NULL) {
 		INP_LOCK_ASSERT(inp);
 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
 			error = EISCONN;
 			goto release;
 		}
 
 		/*
 		 * Jail may rewrite the destination address, so let it do
 		 * that before we use it.
 		 */
 		error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
 		if (error)
 			goto release;
 
 		/*
 		 * If a local address or port hasn't yet been selected, or if
 		 * the destination address needs to be rewritten due to using
 		 * a special INADDR_ constant, invoke in_pcbconnect_setup()
 		 * to do the heavy lifting.  Once a port is selected, we
 		 * commit the binding back to the socket; we also commit the
 		 * binding of the address if in jail.
 		 *
 		 * If we already have a valid binding and we're not
 		 * requesting a destination address rewrite, use a fast path.
 		 */
 		if (inp->inp_laddr.s_addr == INADDR_ANY ||
 		    inp->inp_lport == 0 ||
 		    sin->sin_addr.s_addr == INADDR_ANY ||
 		    sin->sin_addr.s_addr == INADDR_BROADCAST) {
 			INP_HASH_LOCK_ASSERT(pcbinfo);
 			error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
 			    &lport, &faddr.s_addr, &fport, NULL,
 			    td->td_ucred);
 			if (error)
 				goto release;
 
 			/*
 			 * XXXRW: Why not commit the port if the address is
 			 * !INADDR_ANY?
 			 */
 			/* Commit the local port if newly assigned. */
 			if (inp->inp_laddr.s_addr == INADDR_ANY &&
 			    inp->inp_lport == 0) {
 				INP_WLOCK_ASSERT(inp);
 				INP_HASH_WLOCK_ASSERT(pcbinfo);
 				/*
 				 * Remember addr if jailed, to prevent
 				 * rebinding.
 				 */
 				if (prison_flag(td->td_ucred, PR_IP4))
 					inp->inp_laddr = laddr;
 				inp->inp_lport = lport;
 				if (in_pcbinshash(inp) != 0) {
 					inp->inp_lport = 0;
 					error = EAGAIN;
 					goto release;
 				}
 				inp->inp_flags |= INP_ANONPORT;
 			}
 		} else {
 			faddr = sin->sin_addr;
 			fport = sin->sin_port;
 		}
 	} else {
 		INP_LOCK_ASSERT(inp);
 		faddr = inp->inp_faddr;
 		fport = inp->inp_fport;
 		if (faddr.s_addr == INADDR_ANY) {
 			error = ENOTCONN;
 			goto release;
 		}
 	}
 
 	/*
 	 * Calculate data length and get a mbuf for UDP, IP, and possible
 	 * link-layer headers.  Immediate slide the data pointer back forward
 	 * since we won't use that space at this layer.
 	 */
 	M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
 	if (m == NULL) {
 		error = ENOBUFS;
 		goto release;
 	}
 	m->m_data += max_linkhdr;
 	m->m_len -= max_linkhdr;
 	m->m_pkthdr.len -= max_linkhdr;
 
 	/*
 	 * Fill in mbuf with extended UDP header and addresses and length put
 	 * into network format.
 	 */
 	ui = mtod(m, struct udpiphdr *);
 	bzero(ui->ui_x1, sizeof(ui->ui_x1));	/* XXX still needed? */
 	ui->ui_v = IPVERSION << 4;
 	ui->ui_pr = pr;
 	ui->ui_src = laddr;
 	ui->ui_dst = faddr;
 	ui->ui_sport = lport;
 	ui->ui_dport = fport;
 	ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
 	if (pr == IPPROTO_UDPLITE) {
 		struct udpcb *up;
 		uint16_t plen;
 
 		up = intoudpcb(inp);
 		cscov = up->u_txcslen;
 		plen = (u_short)len + sizeof(struct udphdr);
 		if (cscov >= plen)
 			cscov = 0;
 		ui->ui_len = htons(plen);
 		ui->ui_ulen = htons(cscov);
 		/*
 		 * For UDP-Lite, checksum coverage length of zero means
 		 * the entire UDPLite packet is covered by the checksum.
 		 */
 		cscov_partial = (cscov == 0) ? 0 : 1;
 	}
 
 	/*
 	 * Set the Don't Fragment bit in the IP header.
 	 */
 	if (inp->inp_flags & INP_DONTFRAG) {
 		struct ip *ip;
 
 		ip = (struct ip *)&ui->ui_i;
 		ip->ip_off |= htons(IP_DF);
 	}
 
 	ipflags = 0;
 	if (inp->inp_socket->so_options & SO_DONTROUTE)
 		ipflags |= IP_ROUTETOIF;
 	if (inp->inp_socket->so_options & SO_BROADCAST)
 		ipflags |= IP_ALLOWBROADCAST;
 	if (inp->inp_flags & INP_ONESBCAST)
 		ipflags |= IP_SENDONES;
 
 #ifdef MAC
 	mac_inpcb_create_mbuf(inp, m);
 #endif
 
 	/*
 	 * Set up checksum and output datagram.
 	 */
 	ui->ui_sum = 0;
 	if (pr == IPPROTO_UDPLITE) {
 		if (inp->inp_flags & INP_ONESBCAST)
 			faddr.s_addr = INADDR_BROADCAST;
 		if (cscov_partial) {
 			if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
 				ui->ui_sum = 0xffff;
 		} else {
 			if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
 				ui->ui_sum = 0xffff;
 		}
 	} else if (V_udp_cksum) {
 		if (inp->inp_flags & INP_ONESBCAST)
 			faddr.s_addr = INADDR_BROADCAST;
 		ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
 		    htons((u_short)len + sizeof(struct udphdr) + pr));
 		m->m_pkthdr.csum_flags = CSUM_UDP;
 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
 	}
 	((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
 	((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;	/* XXX */
 	((struct ip *)ui)->ip_tos = tos;		/* XXX */
 	UDPSTAT_INC(udps_opackets);
 
 	/*
 	 * Setup flowid / RSS information for outbound socket.
 	 *
 	 * Once the UDP code decides to set a flowid some other way,
 	 * this allows the flowid to be overridden by userland.
 	 */
 	if (flowtype != M_HASHTYPE_NONE) {
 		m->m_pkthdr.flowid = flowid;
 		M_HASHTYPE_SET(m, flowtype);
 #ifdef	RSS
 	} else {
 		uint32_t hash_val, hash_type;
 		/*
 		 * Calculate an appropriate RSS hash for UDP and
 		 * UDP Lite.
 		 *
 		 * The called function will take care of figuring out
 		 * whether a 2-tuple or 4-tuple hash is required based
 		 * on the currently configured scheme.
 		 *
 		 * Later later on connected socket values should be
 		 * cached in the inpcb and reused, rather than constantly
 		 * re-calculating it.
 		 *
 		 * UDP Lite is a different protocol number and will
 		 * likely end up being hashed as a 2-tuple until
 		 * RSS / NICs grow UDP Lite protocol awareness.
 		 */
 		if (rss_proto_software_hash_v4(faddr, laddr, fport, lport,
 		    pr, &hash_val, &hash_type) == 0) {
 			m->m_pkthdr.flowid = hash_val;
 			M_HASHTYPE_SET(m, hash_type);
 		}
 #endif
 	}
 
 #ifdef	RSS
 	/*
 	 * Don't override with the inp cached flowid value.
 	 *
 	 * Depending upon the kind of send being done, the inp
 	 * flowid/flowtype values may actually not be appropriate
 	 * for this particular socket send.
 	 *
 	 * We should either leave the flowid at zero (which is what is
 	 * currently done) or set it to some software generated
 	 * hash value based on the packet contents.
 	 */
 	ipflags |= IP_NODEFAULTFLOWID;
 #endif	/* RSS */
 
 	if (unlock_udbinfo == UH_WLOCKED)
 		INP_HASH_WUNLOCK(pcbinfo);
 	else if (unlock_udbinfo == UH_RLOCKED)
 		INP_HASH_RUNLOCK_ET(pcbinfo, et);
 	if (pr == IPPROTO_UDPLITE)
 		UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
 	else
 		UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
 	error = ip_output(m, inp->inp_options,
 	    (unlock_inp == UH_WLOCKED ? &inp->inp_route : NULL), ipflags,
 	    inp->inp_moptions, inp);
 	if (unlock_inp == UH_WLOCKED)
 		INP_WUNLOCK(inp);
 	else
 		INP_RUNLOCK(inp);
 	return (error);
 
 release:
 	if (unlock_udbinfo == UH_WLOCKED) {
 		KASSERT(unlock_inp == UH_WLOCKED,
 		    ("%s: excl udbinfo lock, shared inp lock", __func__));
 		INP_HASH_WUNLOCK(pcbinfo);
 		INP_WUNLOCK(inp);
 	} else if (unlock_udbinfo == UH_RLOCKED) {
 		KASSERT(unlock_inp == UH_RLOCKED,
 		    ("%s: shared udbinfo lock, excl inp lock", __func__));
 		INP_HASH_RUNLOCK_ET(pcbinfo, et);
 		INP_RUNLOCK(inp);
 	} else if (unlock_inp == UH_WLOCKED)
 		INP_WUNLOCK(inp);
 	else
 		INP_RUNLOCK(inp);
 	m_freem(m);
 	return (error);
 }
 
 static void
 udp_abort(struct socket *so)
 {
 	struct inpcb *inp;
 	struct inpcbinfo *pcbinfo;
 
 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
 	INP_WLOCK(inp);
 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
 		INP_HASH_WLOCK(pcbinfo);
 		in_pcbdisconnect(inp);
 		inp->inp_laddr.s_addr = INADDR_ANY;
 		INP_HASH_WUNLOCK(pcbinfo);
 		soisdisconnected(so);
 	}
 	INP_WUNLOCK(inp);
 }
 
 static int
 udp_attach(struct socket *so, int proto, struct thread *td)
 {
 	static uint32_t udp_flowid;
 	struct inpcb *inp;
 	struct inpcbinfo *pcbinfo;
 	int error;
 
 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 	inp = sotoinpcb(so);
 	KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
 	error = soreserve(so, udp_sendspace, udp_recvspace);
 	if (error)
 		return (error);
 	INP_INFO_WLOCK(pcbinfo);
 	error = in_pcballoc(so, pcbinfo);
 	if (error) {
 		INP_INFO_WUNLOCK(pcbinfo);
 		return (error);
 	}
 
 	inp = sotoinpcb(so);
 	inp->inp_vflag |= INP_IPV4;
 	inp->inp_ip_ttl = V_ip_defttl;
 	inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
 	inp->inp_flowtype = M_HASHTYPE_OPAQUE;
 
 	error = udp_newudpcb(inp);
 	if (error) {
 		in_pcbdetach(inp);
 		in_pcbfree(inp);
 		INP_INFO_WUNLOCK(pcbinfo);
 		return (error);
 	}
 
 	INP_WUNLOCK(inp);
 	INP_INFO_WUNLOCK(pcbinfo);
 	return (0);
 }
 #endif /* INET */
 
 int
 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
 {
 	struct inpcb *inp;
 	struct udpcb *up;
 
 	KASSERT(so->so_type == SOCK_DGRAM,
 	    ("udp_set_kernel_tunneling: !dgram"));
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
 	INP_WLOCK(inp);
 	up = intoudpcb(inp);
 	if ((up->u_tun_func != NULL) ||
 	    (up->u_icmp_func != NULL)) {
 		INP_WUNLOCK(inp);
 		return (EBUSY);
 	}
 	up->u_tun_func = f;
 	up->u_icmp_func = i;
 	up->u_tun_ctx = ctx;
 	INP_WUNLOCK(inp);
 	return (0);
 }
 
 #ifdef INET
 static int
 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
 {
 	struct inpcb *inp;
 	struct inpcbinfo *pcbinfo;
 	int error;
 
 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
 	INP_WLOCK(inp);
 	INP_HASH_WLOCK(pcbinfo);
 	error = in_pcbbind(inp, nam, td->td_ucred);
 	INP_HASH_WUNLOCK(pcbinfo);
 	INP_WUNLOCK(inp);
 	return (error);
 }
 
 static void
 udp_close(struct socket *so)
 {
 	struct inpcb *inp;
 	struct inpcbinfo *pcbinfo;
 
 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_close: inp == NULL"));
 	INP_WLOCK(inp);
 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
 		INP_HASH_WLOCK(pcbinfo);
 		in_pcbdisconnect(inp);
 		inp->inp_laddr.s_addr = INADDR_ANY;
 		INP_HASH_WUNLOCK(pcbinfo);
 		soisdisconnected(so);
 	}
 	INP_WUNLOCK(inp);
 }
 
 static int
 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 {
 	struct inpcb *inp;
 	struct inpcbinfo *pcbinfo;
 	struct sockaddr_in *sin;
 	int error;
 
 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
 	INP_WLOCK(inp);
 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
 		INP_WUNLOCK(inp);
 		return (EISCONN);
 	}
 	sin = (struct sockaddr_in *)nam;
 	error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
 	if (error != 0) {
 		INP_WUNLOCK(inp);
 		return (error);
 	}
 	INP_HASH_WLOCK(pcbinfo);
 	error = in_pcbconnect(inp, nam, td->td_ucred);
 	INP_HASH_WUNLOCK(pcbinfo);
 	if (error == 0)
 		soisconnected(so);
 	INP_WUNLOCK(inp);
 	return (error);
 }
 
 static void
 udp_detach(struct socket *so)
 {
 	struct inpcb *inp;
 	struct inpcbinfo *pcbinfo;
 	struct udpcb *up;
 
 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
 	KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
 	    ("udp_detach: not disconnected"));
 	INP_INFO_WLOCK(pcbinfo);
 	INP_WLOCK(inp);
 	up = intoudpcb(inp);
 	KASSERT(up != NULL, ("%s: up == NULL", __func__));
 	inp->inp_ppcb = NULL;
 	in_pcbdetach(inp);
 	in_pcbfree(inp);
 	INP_INFO_WUNLOCK(pcbinfo);
 	udp_discardcb(up);
 }
 
 static int
 udp_disconnect(struct socket *so)
 {
 	struct inpcb *inp;
 	struct inpcbinfo *pcbinfo;
 
 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
 	INP_WLOCK(inp);
 	if (inp->inp_faddr.s_addr == INADDR_ANY) {
 		INP_WUNLOCK(inp);
 		return (ENOTCONN);
 	}
 	INP_HASH_WLOCK(pcbinfo);
 	in_pcbdisconnect(inp);
 	inp->inp_laddr.s_addr = INADDR_ANY;
 	INP_HASH_WUNLOCK(pcbinfo);
 	SOCK_LOCK(so);
 	so->so_state &= ~SS_ISCONNECTED;		/* XXX */
 	SOCK_UNLOCK(so);
 	INP_WUNLOCK(inp);
 	return (0);
 }
 
 static int
 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
     struct mbuf *control, struct thread *td)
 {
 	struct inpcb *inp;
 
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_send: inp == NULL"));
 	return (udp_output(inp, m, addr, control, td));
 }
 #endif /* INET */
 
 int
 udp_shutdown(struct socket *so)
 {
 	struct inpcb *inp;
 
 	inp = sotoinpcb(so);
 	KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
 	INP_WLOCK(inp);
 	socantsendmore(so);
 	INP_WUNLOCK(inp);
 	return (0);
 }
 
 #ifdef INET
 struct pr_usrreqs udp_usrreqs = {
 	.pru_abort =		udp_abort,
 	.pru_attach =		udp_attach,
 	.pru_bind =		udp_bind,
 	.pru_connect =		udp_connect,
 	.pru_control =		in_control,
 	.pru_detach =		udp_detach,
 	.pru_disconnect =	udp_disconnect,
 	.pru_peeraddr =		in_getpeeraddr,
 	.pru_send =		udp_send,
 	.pru_soreceive =	soreceive_dgram,
 	.pru_sosend =		sosend_dgram,
 	.pru_shutdown =		udp_shutdown,
 	.pru_sockaddr =		in_getsockaddr,
 	.pru_sosetlabel =	in_pcbsosetlabel,
 	.pru_close =		udp_close,
 };
 #endif /* INET */