xref: /dragonfly/sys/netinet6/udp6_output.c (revision 0cfebe3d)
1 /*	$FreeBSD: src/sys/netinet6/udp6_output.c,v 1.1.2.6 2003/01/23 21:06:47 sam Exp $	*/
2 /*	$DragonFly: src/sys/netinet6/udp6_output.c,v 1.8 2006/12/29 18:02:56 victor Exp $	*/
3 /*	$KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $	*/
4 
5 /*
6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /*
35  * Copyright (c) 1982, 1986, 1989, 1993
36  *	The Regents of the University of California.  All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. All advertising materials mentioning features or use of this software
47  *    must display the following acknowledgement:
48  *	This product includes software developed by the University of
49  *	California, Berkeley and its contributors.
50  * 4. Neither the name of the University nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  *
66  *	@(#)udp_var.h	8.1 (Berkeley) 6/10/93
67  */
68 
69 #include "opt_ipsec.h"
70 #include "opt_inet.h"
71 #include "opt_inet6.h"
72 
73 #include <sys/param.h>
74 #include <sys/malloc.h>
75 #include <sys/mbuf.h>
76 #include <sys/protosw.h>
77 #include <sys/socket.h>
78 #include <sys/socketvar.h>
79 #include <sys/sysctl.h>
80 #include <sys/errno.h>
81 #include <sys/stat.h>
82 #include <sys/systm.h>
83 #include <sys/proc.h>
84 #include <sys/syslog.h>
85 
86 #include <net/if.h>
87 #include <net/route.h>
88 #include <net/if_types.h>
89 
90 #include <netinet/in.h>
91 #include <netinet/in_var.h>
92 #include <netinet/in_systm.h>
93 #include <netinet/ip.h>
94 #include <netinet/ip_var.h>
95 #include <netinet/in_pcb.h>
96 #include <netinet/udp.h>
97 #include <netinet/udp_var.h>
98 #include <netinet/ip6.h>
99 #include <netinet6/ip6_var.h>
100 #include <netinet6/in6_pcb.h>
101 #include <netinet6/udp6_var.h>
102 #include <netinet/icmp6.h>
103 #include <netinet6/ip6protosw.h>
104 
105 #ifdef IPSEC
106 #include <netinet6/ipsec.h>
107 #ifdef INET6
108 #include <netinet6/ipsec6.h>
109 #endif
110 #endif /* IPSEC */
111 
112 #include <net/net_osdep.h>
113 
114 /*
115  * UDP protocol inplementation.
116  * Per RFC 768, August, 1980.
117  */
118 
119 #define in6pcb		inpcb
120 #define udp6stat	udpstat
121 #define udp6s_opackets	udps_opackets
122 
123 int
124 udp6_output(struct in6pcb *in6p, struct mbuf *m, struct sockaddr *addr6,
125 	    struct mbuf *control, struct thread *td)
126 {
127 	u_int32_t ulen = m->m_pkthdr.len;
128 	u_int32_t plen = sizeof(struct udphdr) + ulen;
129 	struct ip6_hdr *ip6;
130 	struct udphdr *udp6;
131 	struct in6_addr *laddr, *faddr;
132 	u_short fport;
133 	int error = 0;
134 	struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
135 	int priv;
136 	int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
137 	int flags;
138 	struct sockaddr_in6 tmp;
139 
140 	priv = !suser(td);	/* 1 if privilaged, 0 if not */
141 	if (control) {
142 		if ((error = ip6_setpktoptions(control, &opt, priv, 0)) != 0)
143 			goto release;
144 		in6p->in6p_outputopts = &opt;
145 	}
146 
147 	if (addr6) {
148 		/*
149 		 * IPv4 version of udp_output calls in_pcbconnect in this case,
150 		 * which needs splnet and affects performance.
151 		 * Since we saw no essential reason for calling in_pcbconnect,
152 		 * we get rid of such kind of logic, and call in6_selectsrc
153 		 * and in6_pcbsetport in order to fill in the local address
154 		 * and the local port.
155 		 */
156 		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr6;
157 		if (sin6->sin6_port == 0) {
158 			error = EADDRNOTAVAIL;
159 			goto release;
160 		}
161 
162 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
163 			/* how about ::ffff:0.0.0.0 case? */
164 			error = EISCONN;
165 			goto release;
166 		}
167 		if (!prison_remote_ip(td, (struct sockaddr *)addr6)) {
168 			error = EAFNOSUPPORT; /* IPv4 only jail */
169 			goto release;
170 		}
171 
172 		/* protect *sin6 from overwrites */
173 		tmp = *sin6;
174 		sin6 = &tmp;
175 
176 		faddr = &sin6->sin6_addr;
177 		fport = sin6->sin6_port; /* allow 0 port */
178 
179 		if (IN6_IS_ADDR_V4MAPPED(faddr)) {
180 			if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
181 				/*
182 				 * I believe we should explicitly discard the
183 				 * packet when mapped addresses are disabled,
184 				 * rather than send the packet as an IPv6 one.
185 				 * If we chose the latter approach, the packet
186 				 * might be sent out on the wire based on the
187 				 * default route, the situation which we'd
188 				 * probably want to avoid.
189 				 * (20010421 jinmei@kame.net)
190 				 */
191 				error = EINVAL;
192 				goto release;
193 			} else
194 				af = AF_INET;
195 		}
196 
197 		/* KAME hack: embed scopeid */
198 		if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0) {
199 			error = EINVAL;
200 			goto release;
201 		}
202 
203 		if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
204 			laddr = in6_selectsrc(sin6, in6p->in6p_outputopts,
205 					      in6p->in6p_moptions,
206 					      &in6p->in6p_route,
207 					      &in6p->in6p_laddr, &error, NULL);
208 		} else
209 			laddr = &in6p->in6p_laddr;	/* XXX */
210 		if (laddr == NULL) {
211 			if (error == 0)
212 				error = EADDRNOTAVAIL;
213 			goto release;
214 		}
215 		if (in6p->in6p_lport == 0 &&
216 		    (error = in6_pcbsetport(laddr, in6p, td)) != 0)
217 			goto release;
218 	} else {
219 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
220 			error = ENOTCONN;
221 			goto release;
222 		}
223 		if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
224 			if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
225 				/*
226 				 * XXX: this case would happen when the
227 				 * application sets the V6ONLY flag after
228 				 * connecting the foreign address.
229 				 * Such applications should be fixed,
230 				 * so we bark here.
231 				 */
232 				log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
233 				    "option was set for a connected socket\n");
234 				error = EINVAL;
235 				goto release;
236 			} else
237 				af = AF_INET;
238 		}
239 		laddr = &in6p->in6p_laddr;
240 		faddr = &in6p->in6p_faddr;
241 		fport = in6p->in6p_fport;
242 	}
243 
244 	if (af == AF_INET)
245 		hlen = sizeof(struct ip);
246 
247 	/*
248 	 * Calculate data length and get a mbuf
249 	 * for UDP and IP6 headers.
250 	 */
251 	M_PREPEND(m, hlen + sizeof(struct udphdr), MB_DONTWAIT);
252 	if (m == 0) {
253 		error = ENOBUFS;
254 		goto release;
255 	}
256 
257 	/*
258 	 * Stuff checksum and output datagram.
259 	 */
260 	udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
261 	udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
262 	udp6->uh_dport = fport;
263 	if (plen <= 0xffff)
264 		udp6->uh_ulen = htons((u_short)plen);
265 	else
266 		udp6->uh_ulen = 0;
267 	udp6->uh_sum = 0;
268 
269 	switch (af) {
270 	case AF_INET6:
271 		ip6 = mtod(m, struct ip6_hdr *);
272 		ip6->ip6_flow	= in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
273 		ip6->ip6_vfc 	&= ~IPV6_VERSION_MASK;
274 		ip6->ip6_vfc 	|= IPV6_VERSION;
275 #if 0				/* ip6_plen will be filled in ip6_output. */
276 		ip6->ip6_plen	= htons((u_short)plen);
277 #endif
278 		ip6->ip6_nxt	= IPPROTO_UDP;
279 		ip6->ip6_hlim	= in6_selecthlim(in6p,
280 						 in6p->in6p_route.ro_rt ?
281 						 in6p->in6p_route.ro_rt->rt_ifp : NULL);
282 		ip6->ip6_src	= *laddr;
283 		ip6->ip6_dst	= *faddr;
284 
285 		if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
286 				sizeof(struct ip6_hdr), plen)) == 0) {
287 			udp6->uh_sum = 0xffff;
288 		}
289 
290 		flags = 0;
291 
292 		udp6stat.udp6s_opackets++;
293 		error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
294 		    flags, in6p->in6p_moptions, NULL, in6p);
295 		break;
296 	case AF_INET:
297 		error = EAFNOSUPPORT;
298 		goto release;
299 	}
300 	goto releaseopt;
301 
302 release:
303 	m_freem(m);
304 
305 releaseopt:
306 	if (control) {
307 		ip6_clearpktopts(in6p->in6p_outputopts, 0, -1);
308 		in6p->in6p_outputopts = stickyopt;
309 		m_freem(control);
310 	}
311 	return (error);
312 }
313