[apple/xnu.git] / bsd / netinet6 / udp6_output.c

/*	$FreeBSD: src/sys/netinet6/udp6_output.c,v 1.1.2.3 2001/08/31 13:49:58 jlemon Exp $	*/
/*	$KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $	*/

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * 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 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.
 */

/*
 * Copyright (c) 1982, 1986, 1989, 1993
 *	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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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_var.h	8.1 (Berkeley) 6/10/93
 */

#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/syslog.h>

#include <net/if.h>
#include <net/route.h>
#include <net/if_types.h>

#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_pcb.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/udp6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6protosw.h>

#ifdef IPSEC
#include <netinet6/ipsec.h>
#ifdef INET6
#include <netinet6/ipsec6.h>
#endif
extern int ipsec_bypass;
#endif /*IPSEC*/

#include "faith.h"

#include <net/net_osdep.h>

/*
 * UDP protocol inplementation.
 * Per RFC 768, August, 1980.
 */

#define in6pcb		inpcb
#define udp6stat	udpstat
#define udp6s_opackets	udps_opackets

int
udp6_output(in6p, m, addr6, control, p)
	struct in6pcb *in6p;
	struct mbuf *m;
	struct mbuf *control;
	struct sockaddr *addr6;
	struct proc *p;
{
	u_int32_t ulen = m->m_pkthdr.len;
	u_int32_t plen = sizeof(struct udphdr) + ulen;
	struct ip6_hdr *ip6;
	struct udphdr *udp6;
	struct in6_addr *laddr, *faddr;
	u_short fport;
	int error = 0;
	struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
	int priv;
	int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
	int flags;
	struct sockaddr_in6 tmp;

	priv = 0;
#ifdef __APPLE__
	if (p && !suser(p->p_ucred, &p->p_acflag))
#else
	if (p && !suser(p))
#endif
		priv = 1;
	if (control) {
		if ((error = ip6_setpktoptions(control, &opt, priv, 0)) != 0)
			goto release;
		in6p->in6p_outputopts = &opt;
	}

	if (addr6) {
		/*
		 * IPv4 version of udp_output calls in_pcbconnect in this case,
		 * which needs splnet and affects performance.
		 * 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.
		 */
		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr6;
		if (sin6->sin6_port == 0) {
			error = EADDRNOTAVAIL;
			goto release;
		}

		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
			/* how about ::ffff:0.0.0.0 case? */
			error = EISCONN;
			goto release;
		}

		/* protect *sin6 from overwrites */
		tmp = *sin6;
		sin6 = &tmp;

		faddr = &sin6->sin6_addr;
		fport = sin6->sin6_port; /* allow 0 port */

		if (IN6_IS_ADDR_V4MAPPED(faddr)) {
			if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
				/*
				 * I believe we should explicitly discard the
				 * packet when mapped addresses are disabled,
				 * rather than send the packet as an IPv6 one.
				 * If we chose the latter approach, the packet
				 * might be sent out on the wire based on the
				 * default route, the situation which we'd
				 * probably want to avoid.
				 * (20010421 jinmei@kame.net)
				 */
				error = EINVAL;
				goto release;
			} else
				af = AF_INET;
		}

		/* KAME hack: embed scopeid */
		if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
			error = EINVAL;
			goto release;
		}

		if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
			laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
					      in6p->in6p_moptions,
					      &in6p->in6p_route,
					      &in6p->in6p_laddr, &error);
		} else
			laddr = &in6p->in6p_laddr;	/* XXX */
		if (laddr == NULL) {
			if (error == 0)
				error = EADDRNOTAVAIL;
			goto release;
		}
		if (in6p->in6p_lport == 0 &&
		    (error = in6_pcbsetport(laddr, in6p, p)) != 0)
			goto release;
	} else {
		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
			error = ENOTCONN;
			goto release;
		}
		if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
			if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
				/*
				 * XXX: this case would happen when the
				 * application sets the V6ONLY flag after
				 * connecting the foreign address.
				 * Such applications should be fixed,
				 * so we bark here.
				 */
				log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
				    "option was set for a connected socket\n");
				error = EINVAL;
				goto release;
			} else
				af = AF_INET;
		}
		laddr = &in6p->in6p_laddr;
		faddr = &in6p->in6p_faddr;
		fport = in6p->in6p_fport;
	}

	if (af == AF_INET)
		hlen = sizeof(struct ip);

	/*
	 * Calculate data length and get a mbuf
	 * for UDP and IP6 headers.
	 */
	M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT);
	if (m == 0) {
		error = ENOBUFS;
		goto release;
	}

	/*
	 * Stuff checksum and output datagram.
	 */
	udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
	udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
	udp6->uh_dport = fport;
	if (plen <= 0xffff)
		udp6->uh_ulen = htons((u_short)plen);
	else
		udp6->uh_ulen = 0;
	udp6->uh_sum = 0;

	switch (af) {
	case AF_INET6:
		ip6 = mtod(m, struct ip6_hdr *);
		ip6->ip6_flow	= in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
		ip6->ip6_vfc 	&= ~IPV6_VERSION_MASK;
		ip6->ip6_vfc 	|= IPV6_VERSION;
#if 0				/* ip6_plen will be filled in ip6_output. */
		ip6->ip6_plen	= htons((u_short)plen);
#endif
		ip6->ip6_nxt	= IPPROTO_UDP;
		ip6->ip6_hlim	= in6_selecthlim(in6p,
						 in6p->in6p_route.ro_rt ?
						 in6p->in6p_route.ro_rt->rt_ifp : NULL);
		ip6->ip6_src	= *laddr;
		ip6->ip6_dst	= *faddr;

		if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
				sizeof(struct ip6_hdr), plen)) == 0) {
			udp6->uh_sum = 0xffff;
		}

		flags = 0;

		udp6stat.udp6s_opackets++;
#ifdef IPSEC
		if (ipsec_bypass == 0 && ipsec_setsocket(m, in6p->in6p_socket) != 0) {
			error = ENOBUFS;
			goto release;
		}
#endif /*IPSEC*/
		error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
		    flags, in6p->in6p_moptions, NULL);
		break;
	case AF_INET:
		error = EAFNOSUPPORT;
		goto release;
	}
	goto releaseopt;

release:
	m_freem(m);

releaseopt:
	if (control) {
		ip6_clearpktopts(in6p->in6p_outputopts, 0, -1);
		in6p->in6p_outputopts = stickyopt;
		m_freem(control);
	}
	return(error);
}
Commit	Line	Data
9bccf70c A	1	/* $FreeBSD: src/sys/netinet6/udp6_output.c,v 1.1.2.3 2001/08/31 13:49:58 jlemon Exp $ */
	2	/* $KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $ */
	3
	4	/*
	5	* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
	6	* All rights reserved.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	* 1. Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* 2. Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
	16	* 3. Neither the name of the project nor the names of its contributors
	17	* may be used to endorse or promote products derived from this software
	18	* without specific prior written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
	21	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
	24	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	* SUCH DAMAGE.
	31	*/
	32
	33	/*
	34	* Copyright (c) 1982, 1986, 1989, 1993
	35	* The Regents of the University of California. All rights reserved.
	36	*
	37	* Redistribution and use in source and binary forms, with or without
	38	* modification, are permitted provided that the following conditions
	39	* are met:
	40	* 1. Redistributions of source code must retain the above copyright
	41	* notice, this list of conditions and the following disclaimer.
	42	* 2. Redistributions in binary form must reproduce the above copyright
	43	* notice, this list of conditions and the following disclaimer in the
	44	* documentation and/or other materials provided with the distribution.
	45	* 3. All advertising materials mentioning features or use of this software
	46	* must display the following acknowledgement:
	47	* This product includes software developed by the University of
	48	* California, Berkeley and its contributors.
	49	* 4. Neither the name of the University nor the names of its contributors
	50	* may be used to endorse or promote products derived from this software
	51	* without specific prior written permission.
	52	*
	53	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	54	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	55	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	56	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	57	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	58	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	59	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	60	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	61	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	62	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	63	* SUCH DAMAGE.
	64	*
65	* @(#)udp_var.h 8.1 (Berkeley) 6/10/93
66	*/
67
68	#include <sys/param.h>
69	#include <sys/malloc.h>
70	#include <sys/mbuf.h>
71	#include <sys/protosw.h>
72	#include <sys/socket.h>
73	#include <sys/socketvar.h>
74	#include <sys/sysctl.h>
75	#include <sys/errno.h>
76	#include <sys/stat.h>
77	#include <sys/systm.h>
78	#include <sys/proc.h>
79	#include <sys/syslog.h>
80
81	#include <net/if.h>
82	#include <net/route.h>
83	#include <net/if_types.h>
84
85	#include <netinet/in.h>
86	#include <netinet/in_var.h>
87	#include <netinet/in_systm.h>
88	#include <netinet/ip.h>
89	#include <netinet/ip_var.h>
90	#include <netinet/in_pcb.h>
91	#include <netinet/udp.h>
92	#include <netinet/udp_var.h>
93	#include <netinet/ip6.h>
94	#include <netinet6/ip6_var.h>
95	#include <netinet6/in6_pcb.h>
96	#include <netinet6/udp6_var.h>
97	#include <netinet/icmp6.h>
98	#include <netinet6/ip6protosw.h>
99
100	#ifdef IPSEC
101	#include <netinet6/ipsec.h>
102	#ifdef INET6
103	#include <netinet6/ipsec6.h>
104	#endif
105	extern int ipsec_bypass;
106	#endif /IPSEC/
107
108	#include "faith.h"
109
110	#include <net/net_osdep.h>
111
112	/*
113	* UDP protocol inplementation.
114	* Per RFC 768, August, 1980.
115	*/
116
117	#define in6pcb inpcb
118	#define udp6stat udpstat
119	#define udp6s_opackets udps_opackets
120
121	int
122	udp6_output(in6p, m, addr6, control, p)
123	struct in6pcb *in6p;
124	struct mbuf *m;
125	struct mbuf *control;
126	struct sockaddr *addr6;
127	struct proc *p;
128	{
129	u_int32_t ulen = m->m_pkthdr.len;
130	u_int32_t plen = sizeof(struct udphdr) + ulen;
131	struct ip6_hdr *ip6;
132	struct udphdr *udp6;
133	struct in6_addr laddr, faddr;
134	u_short fport;
135	int error = 0;
136	struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
137	int priv;
138	int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
139	int flags;
140	struct sockaddr_in6 tmp;
141
142	priv = 0;
143	#ifdef __APPLE__
144	if (p && !suser(p->p_ucred, &p->p_acflag))
145	#else
146	if (p && !suser(p))
147	#endif
148	priv = 1;
149	if (control) {
150	if ((error = ip6_setpktoptions(control, &opt, priv, 0)) != 0)
151	goto release;
152	in6p->in6p_outputopts = &opt;
153	}
154
155	if (addr6) {
156	/*
157	* IPv4 version of udp_output calls in_pcbconnect in this case,
158	* which needs splnet and affects performance.
159	* Since we saw no essential reason for calling in_pcbconnect,
160	* we get rid of such kind of logic, and call in6_selectsrc
161	* and in6_pcbsetport in order to fill in the local address
162	* and the local port.
163	*/
164	struct sockaddr_in6 sin6 = (struct sockaddr_in6 )addr6;
165	if (sin6->sin6_port == 0) {
166	error = EADDRNOTAVAIL;
167	goto release;
168	}
169
170	if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
171	/* how about ::ffff:0.0.0.0 case? */
172	error = EISCONN;
173	goto release;
174	}
175
176	/* protect sin6 from overwrites /
177	tmp = *sin6;
178	sin6 = &tmp;
179
180	faddr = &sin6->sin6_addr;
181	fport = sin6->sin6_port; /* allow 0 port */
182
183	if (IN6_IS_ADDR_V4MAPPED(faddr)) {
184	if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
185	/*
186	* I believe we should explicitly discard the
187	* packet when mapped addresses are disabled,
188	* rather than send the packet as an IPv6 one.
189	* If we chose the latter approach, the packet
190	* might be sent out on the wire based on the
191	* default route, the situation which we'd
192	* probably want to avoid.
193	* (20010421 jinmei@kame.net)
194	*/
195	error = EINVAL;
196	goto release;
197	} else
198	af = AF_INET;
199	}
200
201	/* KAME hack: embed scopeid */
202	if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
203	error = EINVAL;
204	goto release;
205	}
206
207	if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
208	laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
209	in6p->in6p_moptions,
210	&in6p->in6p_route,
211	&in6p->in6p_laddr, &error);
212	} else
213	laddr = &in6p->in6p_laddr; /* XXX */
214	if (laddr == NULL) {
215	if (error == 0)
216	error = EADDRNOTAVAIL;
217	goto release;
218	}
219	if (in6p->in6p_lport == 0 &&
220	(error = in6_pcbsetport(laddr, in6p, p)) != 0)
221	goto release;
222	} else {
223	if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
224	error = ENOTCONN;
225	goto release;
226	}
227	if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
228	if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
229	/*
230	* XXX: this case would happen when the
231	* application sets the V6ONLY flag after
232	* connecting the foreign address.
233	* Such applications should be fixed,
234	* so we bark here.
235	*/
236	log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
237	"option was set for a connected socket\n");
238	error = EINVAL;
239	goto release;
240	} else
241	af = AF_INET;
242	}
243	laddr = &in6p->in6p_laddr;
244	faddr = &in6p->in6p_faddr;
245	fport = in6p->in6p_fport;
246	}
247
248	if (af == AF_INET)
249	hlen = sizeof(struct ip);
250
251	/*
252	* Calculate data length and get a mbuf
253	* for UDP and IP6 headers.
254	*/
255	M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT);
256	if (m == 0) {
257	error = ENOBUFS;
258	goto release;
259	}
260
261	/*
262	* Stuff checksum and output datagram.
263	*/
264	udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
265	udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
266	udp6->uh_dport = fport;
267	if (plen <= 0xffff)
268	udp6->uh_ulen = htons((u_short)plen);
269	else
270	udp6->uh_ulen = 0;
271	udp6->uh_sum = 0;
272
273	switch (af) {
274	case AF_INET6:
275	ip6 = mtod(m, struct ip6_hdr *);
276	ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
277	ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
278	ip6->ip6_vfc \|= IPV6_VERSION;
279	#if 0 /* ip6_plen will be filled in ip6_output. */
280	ip6->ip6_plen = htons((u_short)plen);
281	#endif
282	ip6->ip6_nxt = IPPROTO_UDP;
283	ip6->ip6_hlim = in6_selecthlim(in6p,
284	in6p->in6p_route.ro_rt ?
285	in6p->in6p_route.ro_rt->rt_ifp : NULL);
286	ip6->ip6_src = *laddr;
287	ip6->ip6_dst = *faddr;
288
289	if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
290	sizeof(struct ip6_hdr), plen)) == 0) {
291	udp6->uh_sum = 0xffff;
292	}
293
294	flags = 0;
295
296	udp6stat.udp6s_opackets++;
297	#ifdef IPSEC
298	if (ipsec_bypass == 0 && ipsec_setsocket(m, in6p->in6p_socket) != 0) {
299	error = ENOBUFS;
300	goto release;
301	}
302	#endif /IPSEC/
303	error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
304	flags, in6p->in6p_moptions, NULL);
305	break;
306	case AF_INET:
307	error = EAFNOSUPPORT;
308	goto release;
309	}
310	goto releaseopt;
311
312	release:
313	m_freem(m);
314
315	releaseopt:
316	if (control) {
317	ip6_clearpktopts(in6p->in6p_outputopts, 0, -1);
318	in6p->in6p_outputopts = stickyopt;
319	m_freem(control);
320	}
321	return(error);
322	}