freebsd-skq/sys/netinet6/udp6_usrreq.c
Navdeep Parhar 72cc43df17 Add a knob to allow zero UDP checksums for UDP/IPv6 traffic on the given UDP port.
This will be used by some upcoming changes to if_vxlan(4).  RFC 7348 (VXLAN)
says that the UDP checksum "SHOULD be transmitted as zero.  When a packet is
received with a UDP checksum of zero, it MUST be accepted for decapsulation."
But the original IPv6 RFCs did not allow zero UDP checksum.  RFC 6935 attempts
to resolve this.

Reviewed by:	kib@
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D25873
2020-09-18 02:21:15 +00:00

1391 lines
36 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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 project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $KAME: udp6_usrreq.c,v 1.27 2001/05/21 05:45:10 jinmei Exp $
* $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $
*/
/*-
* Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
* The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the 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/jail.h>
#include <sys/kernel.h>
#include <sys/lock.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 <net/if.h>
#include <net/if_var.h>
#include <net/if_types.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>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/udplite.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/in6_rss.h>
#include <netinet6/udp6_var.h>
#include <netinet6/scope6_var.h>
#include <netipsec/ipsec_support.h>
#include <security/mac/mac_framework.h>
VNET_DEFINE(int, zero_checksum_port) = 0;
#define V_zero_checksum_port VNET(zero_checksum_port)
SYSCTL_INT(_net_inet6_udp6, OID_AUTO, rfc6935_port, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(zero_checksum_port), 0,
"Zero UDP checksum allowed for traffic to/from this port.");
/*
* UDP protocol implementation.
* Per RFC 768, August, 1980.
*/
extern struct protosw inetsw[];
static void udp6_detach(struct socket *so);
static int
udp6_append(struct inpcb *inp, struct mbuf *n, int off,
struct sockaddr_in6 *fromsa)
{
struct socket *so;
struct mbuf *opts = NULL, *tmp_opts;
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 *)&fromsa[0],
up->u_tun_ctx);
INP_RLOCK(inp);
return (in_pcbrele_rlocked(inp));
}
#if defined(IPSEC) || defined(IPSEC_SUPPORT)
/* Check AH/ESP integrity. */
if (IPSEC_ENABLED(ipv6)) {
if (IPSEC_CHECK_POLICY(ipv6, n, inp) != 0) {
m_freem(n);
return (0);
}
}
#endif /* IPSEC */
#ifdef MAC
if (mac_inpcb_check_deliver(inp, n) != 0) {
m_freem(n);
return (0);
}
#endif
opts = NULL;
if (inp->inp_flags & INP_CONTROLOPTS ||
inp->inp_socket->so_options & SO_TIMESTAMP)
ip6_savecontrol(inp, n, &opts);
if ((inp->inp_vflag & INP_IPV6) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
tmp_opts = sbcreatecontrol((caddr_t)&fromsa[1],
sizeof(struct sockaddr_in6), IPV6_ORIGDSTADDR, IPPROTO_IPV6);
if (tmp_opts) {
if (opts) {
tmp_opts->m_next = opts;
opts = tmp_opts;
} else
opts = tmp_opts;
}
}
m_adj(n, off + sizeof(struct udphdr));
so = inp->inp_socket;
SOCKBUF_LOCK(&so->so_rcv);
if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)&fromsa[0], 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
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[2];
struct m_tag *fwd_tag;
uint16_t uh_sum;
uint8_t nxt;
NET_EPOCH_ASSERT();
ifp = m->m_pkthdr.rcvif;
if (m->m_len < off + sizeof(struct udphdr)) {
m = m_pullup(m, off + sizeof(struct udphdr));
if (m == NULL) {
IP6STAT_INC(ip6s_exthdrtoolong);
*mp = NULL;
return (IPPROTO_DONE);
}
}
ip6 = mtod(m, struct ip6_hdr *);
uh = (struct udphdr *)((caddr_t)ip6 + off);
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);
/*
* dport 0 was rejected earlier so this is OK even if
* zero_checksum_port is 0 (which is its default value).
*/
if (ntohs(uh->uh_dport) == V_zero_checksum_port)
goto skip_checksum;
else
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;
}
skip_checksum:
/*
* Construct sockaddr format source address.
*/
init_sin6(&fromsa[0], m, 0);
fromsa[0].sin6_port = uh->uh_sport;
init_sin6(&fromsa[1], m, 1);
fromsa[1].sin6_port = uh->uh_dport;
pcbinfo = udp_get_inpcbinfo(nxt);
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct inpcb *last;
struct inpcbhead *pcblist;
struct ip6_moptions *imo;
/*
* 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;
CK_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);
if (__predict_false(inp->inp_flags2 & INP_FREED)) {
INP_RUNLOCK(inp);
continue;
}
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[0]);
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_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
NULL) {
INP_RLOCK(last);
if (__predict_true(last->inp_flags2 & INP_FREED) == 0) {
if (nxt == IPPROTO_UDPLITE)
UDPLITE_PROBE(receive, NULL, last,
ip6, last, uh);
else
UDP_PROBE(receive, NULL, last,
ip6, last, uh);
if (udp6_append(last, n, off, fromsa)) {
/* XXX-BZ do we leak m here? */
*mp = NULL;
return (IPPROTO_DONE);
}
}
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_noport);
UDPSTAT_INC(udps_noportmcast);
goto badunlocked;
}
INP_RLOCK(last);
if (__predict_true(last->inp_flags2 & INP_FREED) == 0) {
if (nxt == IPPROTO_UDPLITE)
UDPLITE_PROBE(receive, NULL, last, ip6, last, uh);
else
UDP_PROBE(receive, NULL, last, ip6, last, uh);
if (udp6_append(last, m, off, fromsa) == 0)
INP_RUNLOCK(last);
} else
INP_RUNLOCK(last);
*mp = NULL;
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 (V_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));
}
if (nxt == IPPROTO_UDPLITE)
UDPLITE_PROBE(receive, NULL, NULL, ip6, NULL, uh);
else
UDP_PROBE(receive, NULL, NULL, ip6, NULL, uh);
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;
icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
*mp = NULL;
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);
*mp = NULL;
return (IPPROTO_DONE);
}
}
if (nxt == IPPROTO_UDPLITE)
UDPLITE_PROBE(receive, NULL, inp, ip6, inp, uh);
else
UDP_PROBE(receive, NULL, inp, ip6, inp, uh);
if (udp6_append(inp, m, off, fromsa) == 0)
INP_RUNLOCK(inp);
*mp = NULL;
return (IPPROTO_DONE);
badunlocked:
m_freem(m);
*mp = NULL;
return (IPPROTO_DONE);
}
static void
udp6_common_ctlinput(int cmd, struct sockaddr *sa, void *d,
struct inpcbinfo *pcbinfo)
{
struct udphdr uh;
struct ip6_hdr *ip6;
struct mbuf *m;
int off = 0;
struct ip6ctlparam *ip6cp = NULL;
const struct sockaddr_in6 *sa6_src = NULL;
void *cmdarg;
struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
struct udp_portonly {
u_int16_t uh_sport;
u_int16_t uh_dport;
} *uhp;
if (sa->sa_family != AF_INET6 ||
sa->sa_len != sizeof(struct sockaddr_in6))
return;
if ((unsigned)cmd >= PRC_NCMDS)
return;
if (PRC_IS_REDIRECT(cmd))
notify = in6_rtchange, d = NULL;
else if (cmd == PRC_HOSTDEAD)
d = NULL;
else if (inet6ctlerrmap[cmd] == 0)
return;
/* if the parameter is from icmp6, decode it. */
if (d != NULL) {
ip6cp = (struct ip6ctlparam *)d;
m = ip6cp->ip6c_m;
ip6 = ip6cp->ip6c_ip6;
off = ip6cp->ip6c_off;
cmdarg = ip6cp->ip6c_cmdarg;
sa6_src = ip6cp->ip6c_src;
} else {
m = NULL;
ip6 = NULL;
cmdarg = NULL;
sa6_src = &sa6_any;
}
if (ip6) {
/*
* XXX: We assume that when IPV6 is non NULL,
* M and OFF are valid.
*/
/* Check if we can safely examine src and dst ports. */
if (m->m_pkthdr.len < off + sizeof(*uhp))
return;
bzero(&uh, sizeof(uh));
m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
if (!PRC_IS_REDIRECT(cmd)) {
/* Check to see if its tunneled */
struct inpcb *inp;
inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_dst,
uh.uh_dport, &ip6->ip6_src, uh.uh_sport,
INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
m->m_pkthdr.rcvif, m);
if (inp != NULL) {
struct udpcb *up;
up = intoudpcb(inp);
if (up->u_icmp_func) {
/* Yes it is. */
INP_RUNLOCK(inp);
(*up->u_icmp_func)(cmd, (struct sockaddr *)ip6cp->ip6c_src,
d, up->u_tun_ctx);
return;
} else {
/* Can't find it. */
INP_RUNLOCK(inp);
}
}
}
(void)in6_pcbnotify(pcbinfo, sa, uh.uh_dport,
(struct sockaddr *)ip6cp->ip6c_src, uh.uh_sport, cmd,
cmdarg, notify);
} else
(void)in6_pcbnotify(pcbinfo, sa, 0,
(const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
}
void
udp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
{
return (udp6_common_ctlinput(cmd, sa, d, &V_udbinfo));
}
void
udplite6_ctlinput(int cmd, struct sockaddr *sa, void *d)
{
return (udp6_common_ctlinput(cmd, sa, d, &V_ulitecbinfo));
}
static int
udp6_getcred(SYSCTL_HANDLER_ARGS)
{
struct xucred xuc;
struct sockaddr_in6 addrs[2];
struct epoch_tracker et;
struct inpcb *inp;
int error;
error = priv_check(req->td, PRIV_NETINET_GETCRED);
if (error)
return (error);
if (req->newlen != sizeof(addrs))
return (EINVAL);
if (req->oldlen != sizeof(struct xucred))
return (EINVAL);
error = SYSCTL_IN(req, addrs, sizeof(addrs));
if (error)
return (error);
if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
(error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
return (error);
}
NET_EPOCH_ENTER(et);
inp = in6_pcblookup(&V_udbinfo, &addrs[1].sin6_addr,
addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port,
INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
NET_EPOCH_EXIT(et);
if (inp != NULL) {
INP_RLOCK_ASSERT(inp);
if (inp->inp_socket == NULL)
error = ENOENT;
if (error == 0)
error = cr_canseesocket(req->td->td_ucred,
inp->inp_socket);
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_inet6_udp6, OID_AUTO, getcred,
CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_MPSAFE,
0, 0, udp6_getcred, "S,xucred",
"Get the xucred of a UDP6 connection");
static int
udp6_output(struct socket *so, int flags_arg, struct mbuf *m,
struct sockaddr *addr6, struct mbuf *control, struct thread *td)
{
struct inpcb *inp;
struct ip6_hdr *ip6;
struct udphdr *udp6;
struct in6_addr *laddr, *faddr, in6a;
struct ip6_pktopts *optp, opt;
struct sockaddr_in6 *sin6, tmp;
struct epoch_tracker et;
int cscov_partial, error, flags, hlen, scope_ambiguous;
u_int32_t ulen, plen;
uint16_t cscov;
u_short fport;
uint8_t nxt;
/* addr6 has been validated in udp6_send(). */
sin6 = (struct sockaddr_in6 *)addr6;
/*
* In contrast to to IPv4 we do not validate the max. packet length
* here due to IPv6 Jumbograms (RFC2675).
*/
scope_ambiguous = 0;
if (sin6) {
/* Protect *addr6 from overwrites. */
tmp = *sin6;
sin6 = &tmp;
/*
* Application should provide a proper zone ID or the use of
* default zone IDs should be enabled. Unfortunately, some
* applications do not behave as it should, so we need a
* workaround. Even if an appropriate ID is not determined,
* we'll see if we can determine the outgoing interface. If we
* can, determine the zone ID based on the interface below.
*/
if (sin6->sin6_scope_id == 0 && !V_ip6_use_defzone)
scope_ambiguous = 1;
if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0) {
if (control)
m_freem(control);
m_freem(m);
return (error);
}
}
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
/*
* In the following cases we want a write lock on the inp for either
* local operations or for possible route cache updates in the IPv6
* output path:
* - on connected sockets (sin6 is NULL) for route cache updates,
* - when we are not bound to an address and source port (it is
* in6_pcbsetport() which will require the write lock).
*
* We check the inp fields before actually locking the inp, so
* here exists a race, and we may WLOCK the inp and end with already
* bound one by other thread. This is fine.
*/
if (sin6 == NULL || (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
inp->inp_lport == 0))
INP_WLOCK(inp);
else
INP_RLOCK(inp);
nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
IPPROTO_UDP : IPPROTO_UDPLITE;
#ifdef INET
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
int hasv4addr;
if (sin6 == NULL)
hasv4addr = (inp->inp_vflag & INP_IPV4);
else
hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
? 1 : 0;
if (hasv4addr) {
struct pr_usrreqs *pru;
/*
* XXXRW: We release UDP-layer locks before calling
* udp_send() in order to avoid recursion. However,
* this does mean there is a short window where inp's
* fields are unstable. Could this lead to a
* potential race in which the factors causing us to
* select the UDPv4 output routine are invalidated?
*/
INP_UNLOCK(inp);
if (sin6)
in6_sin6_2_sin_in_sock((struct sockaddr *)sin6);
pru = inetsw[ip_protox[nxt]].pr_usrreqs;
/* addr will just be freed in sendit(). */
return ((*pru->pru_send)(so, flags_arg | PRUS_IPV6, m,
(struct sockaddr *)sin6, control, td));
}
} else
#endif
if (sin6 && IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
/*
* Given this is either an IPv6-only socket or no INET is
* supported we will fail the send if the given destination
* address is a v4mapped address.
*
* XXXGL: do we leak m and control?
*/
INP_UNLOCK(inp);
return (EINVAL);
}
if (control) {
if ((error = ip6_setpktopts(control, &opt,
inp->in6p_outputopts, td->td_ucred, nxt)) != 0) {
INP_UNLOCK(inp);
ip6_clearpktopts(&opt, -1);
if (control)
m_freem(control);
m_freem(m);
return (error);
}
optp = &opt;
} else
optp = inp->in6p_outputopts;
NET_EPOCH_ENTER(et);
if (sin6) {
/*
* Since we saw no essential reason for calling in_pcbconnect,
* we get rid of such kind of logic, and call in6_selectsrc
* and in6_pcbsetport in order to fill in the local address
* and the local port.
*/
if (sin6->sin6_port == 0) {
error = EADDRNOTAVAIL;
goto release;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
/* how about ::ffff:0.0.0.0 case? */
error = EISCONN;
goto release;
}
/*
* Given we handle the v4mapped case in the INET block above
* assert here that it must not happen anymore.
*/
KASSERT(!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr),
("%s: sin6(%p)->sin6_addr is v4mapped which we "
"should have handled.", __func__, sin6));
/* This only requires read-locking. */
error = in6_selectsrc_socket(sin6, optp, inp,
td->td_ucred, scope_ambiguous, &in6a, NULL);
if (error)
goto release;
laddr = &in6a;
if (inp->inp_lport == 0) {
struct inpcbinfo *pcbinfo;
INP_WLOCK_ASSERT(inp);
pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
INP_HASH_WLOCK(pcbinfo);
error = in6_pcbsetport(laddr, inp, td->td_ucred);
INP_HASH_WUNLOCK(pcbinfo);
if (error != 0) {
/* Undo an address bind that may have occurred. */
inp->in6p_laddr = in6addr_any;
goto release;
}
}
faddr = &sin6->sin6_addr;
fport = sin6->sin6_port; /* allow 0 port */
} else {
if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
error = ENOTCONN;
goto release;
}
laddr = &inp->in6p_laddr;
faddr = &inp->in6p_faddr;
fport = inp->inp_fport;
}
ulen = m->m_pkthdr.len;
plen = sizeof(struct udphdr) + ulen;
hlen = sizeof(struct ip6_hdr);
/*
* Calculate data length and get a mbuf
* for UDP and IP6 headers.
*/
M_PREPEND(m, hlen + sizeof(struct udphdr), M_NOWAIT);
if (m == NULL) {
error = ENOBUFS;
goto release;
}
/*
* Stuff checksum and output datagram.
*/
cscov = cscov_partial = 0;
udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
udp6->uh_dport = fport;
if (nxt == IPPROTO_UDPLITE) {
struct udpcb *up;
up = intoudpcb(inp);
cscov = up->u_txcslen;
if (cscov >= plen)
cscov = 0;
udp6->uh_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;
} else if (plen <= 0xffff)
udp6->uh_ulen = htons((u_short)plen);
else
udp6->uh_ulen = 0;
udp6->uh_sum = 0;
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = inp->inp_flow & IPV6_FLOWINFO_MASK;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_plen = htons((u_short)plen);
ip6->ip6_nxt = nxt;
ip6->ip6_hlim = in6_selecthlim(inp, NULL);
ip6->ip6_src = *laddr;
ip6->ip6_dst = *faddr;
#ifdef MAC
mac_inpcb_create_mbuf(inp, m);
#endif
if (cscov_partial) {
if ((udp6->uh_sum = in6_cksum_partial(m, nxt,
sizeof(struct ip6_hdr), plen, cscov)) == 0)
udp6->uh_sum = 0xffff;
} else {
udp6->uh_sum = in6_cksum_pseudo(ip6, plen, nxt, 0);
m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
}
flags = 0;
#ifdef RSS
{
uint32_t hash_val, hash_type;
uint8_t pr;
pr = inp->inp_socket->so_proto->pr_protocol;
/*
* 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_v6(faddr, laddr, fport,
inp->inp_lport, pr, &hash_val, &hash_type) == 0) {
m->m_pkthdr.flowid = hash_val;
M_HASHTYPE_SET(m, hash_type);
}
/*
* Don't override with the inp cached flowid.
*
* Until the whole UDP path is vetted, it may actually
* be incorrect.
*/
flags |= IP_NODEFAULTFLOWID;
}
#endif
UDPSTAT_INC(udps_opackets);
if (nxt == IPPROTO_UDPLITE)
UDPLITE_PROBE(send, NULL, inp, ip6, inp, udp6);
else
UDP_PROBE(send, NULL, inp, ip6, inp, udp6);
error = ip6_output(m, optp,
INP_WLOCKED(inp) ? &inp->inp_route6 : NULL, flags,
inp->in6p_moptions, NULL, inp);
INP_UNLOCK(inp);
NET_EPOCH_EXIT(et);
if (control) {
ip6_clearpktopts(&opt, -1);
m_freem(control);
}
return (error);
release:
INP_UNLOCK(inp);
NET_EPOCH_EXIT(et);
if (control) {
ip6_clearpktopts(&opt, -1);
m_freem(control);
}
m_freem(m);
return (error);
}
static void
udp6_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, ("udp6_abort: inp == NULL"));
INP_WLOCK(inp);
#ifdef INET
if (inp->inp_vflag & INP_IPV4) {
struct pr_usrreqs *pru;
uint8_t nxt;
nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
IPPROTO_UDP : IPPROTO_UDPLITE;
INP_WUNLOCK(inp);
pru = inetsw[ip_protox[nxt]].pr_usrreqs;
(*pru->pru_abort)(so);
return;
}
#endif
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
INP_HASH_WLOCK(pcbinfo);
in6_pcbdisconnect(inp);
inp->in6p_laddr = in6addr_any;
INP_HASH_WUNLOCK(pcbinfo);
soisdisconnected(so);
}
INP_WUNLOCK(inp);
}
static int
udp6_attach(struct socket *so, int proto, 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, ("udp6_attach: inp != NULL"));
if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
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 = (struct inpcb *)so->so_pcb;
inp->inp_vflag |= INP_IPV6;
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
inp->inp_vflag |= INP_IPV4;
inp->in6p_hops = -1; /* use kernel default */
inp->in6p_cksum = -1; /* just to be sure */
/*
* XXX: ugly!!
* IPv4 TTL initialization is necessary for an IPv6 socket as well,
* because the socket may be bound to an IPv6 wildcard address,
* which may match an IPv4-mapped IPv6 address.
*/
inp->inp_ip_ttl = V_ip_defttl;
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);
}
static int
udp6_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
{
struct inpcb *inp;
struct inpcbinfo *pcbinfo;
int error;
u_char vflagsav;
pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp6_bind: inp == NULL"));
INP_WLOCK(inp);
INP_HASH_WLOCK(pcbinfo);
vflagsav = inp->inp_vflag;
inp->inp_vflag &= ~INP_IPV4;
inp->inp_vflag |= INP_IPV6;
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
struct sockaddr_in6 *sin6_p;
sin6_p = (struct sockaddr_in6 *)nam;
if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
inp->inp_vflag |= INP_IPV4;
#ifdef INET
else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
struct sockaddr_in sin;
in6_sin6_2_sin(&sin, sin6_p);
inp->inp_vflag |= INP_IPV4;
inp->inp_vflag &= ~INP_IPV6;
error = in_pcbbind(inp, (struct sockaddr *)&sin,
td->td_ucred);
goto out;
}
#endif
}
error = in6_pcbbind(inp, nam, td->td_ucred);
#ifdef INET
out:
#endif
if (error != 0)
inp->inp_vflag = vflagsav;
INP_HASH_WUNLOCK(pcbinfo);
INP_WUNLOCK(inp);
return (error);
}
static void
udp6_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, ("udp6_close: inp == NULL"));
INP_WLOCK(inp);
#ifdef INET
if (inp->inp_vflag & INP_IPV4) {
struct pr_usrreqs *pru;
uint8_t nxt;
nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
IPPROTO_UDP : IPPROTO_UDPLITE;
INP_WUNLOCK(inp);
pru = inetsw[ip_protox[nxt]].pr_usrreqs;
(*pru->pru_disconnect)(so);
return;
}
#endif
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
INP_HASH_WLOCK(pcbinfo);
in6_pcbdisconnect(inp);
inp->in6p_laddr = in6addr_any;
INP_HASH_WUNLOCK(pcbinfo);
soisdisconnected(so);
}
INP_WUNLOCK(inp);
}
static int
udp6_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
{
#ifdef INET
struct epoch_tracker et;
#endif
struct inpcb *inp;
struct inpcbinfo *pcbinfo;
struct sockaddr_in6 *sin6;
int error;
u_char vflagsav;
pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
inp = sotoinpcb(so);
sin6 = (struct sockaddr_in6 *)nam;
KASSERT(inp != NULL, ("udp6_connect: inp == NULL"));
/*
* XXXRW: Need to clarify locking of v4/v6 flags.
*/
INP_WLOCK(inp);
#ifdef INET
if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
struct sockaddr_in sin;
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
error = EINVAL;
goto out;
}
if ((inp->inp_vflag & INP_IPV4) == 0) {
error = EAFNOSUPPORT;
goto out;
}
if (inp->inp_faddr.s_addr != INADDR_ANY) {
error = EISCONN;
goto out;
}
in6_sin6_2_sin(&sin, sin6);
error = prison_remote_ip4(td->td_ucred, &sin.sin_addr);
if (error != 0)
goto out;
vflagsav = inp->inp_vflag;
inp->inp_vflag |= INP_IPV4;
inp->inp_vflag &= ~INP_IPV6;
NET_EPOCH_ENTER(et);
INP_HASH_WLOCK(pcbinfo);
error = in_pcbconnect(inp, (struct sockaddr *)&sin,
td->td_ucred);
INP_HASH_WUNLOCK(pcbinfo);
NET_EPOCH_EXIT(et);
/*
* If connect succeeds, mark socket as connected. If
* connect fails and socket is unbound, reset inp_vflag
* field.
*/
if (error == 0)
soisconnected(so);
else if (inp->inp_laddr.s_addr == INADDR_ANY &&
inp->inp_lport == 0)
inp->inp_vflag = vflagsav;
goto out;
} else {
if ((inp->inp_vflag & INP_IPV6) == 0) {
error = EAFNOSUPPORT;
goto out;
}
}
#endif
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
error = EISCONN;
goto out;
}
error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr);
if (error != 0)
goto out;
vflagsav = inp->inp_vflag;
inp->inp_vflag &= ~INP_IPV4;
inp->inp_vflag |= INP_IPV6;
INP_HASH_WLOCK(pcbinfo);
error = in6_pcbconnect(inp, nam, td->td_ucred);
INP_HASH_WUNLOCK(pcbinfo);
/*
* If connect succeeds, mark socket as connected. If
* connect fails and socket is unbound, reset inp_vflag
* field.
*/
if (error == 0)
soisconnected(so);
else if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
inp->inp_lport == 0)
inp->inp_vflag = vflagsav;
out:
INP_WUNLOCK(inp);
return (error);
}
static void
udp6_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, ("udp6_detach: inp == NULL"));
INP_INFO_WLOCK(pcbinfo);
INP_WLOCK(inp);
up = intoudpcb(inp);
KASSERT(up != NULL, ("%s: up == NULL", __func__));
in_pcbdetach(inp);
in_pcbfree(inp);
INP_INFO_WUNLOCK(pcbinfo);
udp_discardcb(up);
}
static int
udp6_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, ("udp6_disconnect: inp == NULL"));
INP_WLOCK(inp);
#ifdef INET
if (inp->inp_vflag & INP_IPV4) {
struct pr_usrreqs *pru;
uint8_t nxt;
nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
IPPROTO_UDP : IPPROTO_UDPLITE;
INP_WUNLOCK(inp);
pru = inetsw[ip_protox[nxt]].pr_usrreqs;
(void)(*pru->pru_disconnect)(so);
return (0);
}
#endif
if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
INP_WUNLOCK(inp);
return (ENOTCONN);
}
INP_HASH_WLOCK(pcbinfo);
in6_pcbdisconnect(inp);
inp->in6p_laddr = in6addr_any;
INP_HASH_WUNLOCK(pcbinfo);
SOCK_LOCK(so);
so->so_state &= ~SS_ISCONNECTED; /* XXX */
SOCK_UNLOCK(so);
INP_WUNLOCK(inp);
return (0);
}
static int
udp6_send(struct socket *so, int flags, struct mbuf *m,
struct sockaddr *addr, struct mbuf *control, struct thread *td)
{
int error;
if (addr) {
if (addr->sa_len != sizeof(struct sockaddr_in6)) {
error = EINVAL;
goto bad;
}
if (addr->sa_family != AF_INET6) {
error = EAFNOSUPPORT;
goto bad;
}
}
return (udp6_output(so, flags, m, addr, control, td));
bad:
if (control)
m_freem(control);
m_freem(m);
return (error);
}
struct pr_usrreqs udp6_usrreqs = {
.pru_abort = udp6_abort,
.pru_attach = udp6_attach,
.pru_bind = udp6_bind,
.pru_connect = udp6_connect,
.pru_control = in6_control,
.pru_detach = udp6_detach,
.pru_disconnect = udp6_disconnect,
.pru_peeraddr = in6_mapped_peeraddr,
.pru_send = udp6_send,
.pru_shutdown = udp_shutdown,
.pru_sockaddr = in6_mapped_sockaddr,
.pru_soreceive = soreceive_dgram,
.pru_sosend = sosend_dgram,
.pru_sosetlabel = in_pcbsosetlabel,
.pru_close = udp6_close
};