1 | /* $NetBSD: udp6_output.c,v 1.54 2016/10/31 04:16:25 ozaki-r Exp $ */ |
2 | /* $KAME: udp6_output.c,v 1.43 2001/10/15 09:19:52 itojun 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. Neither the name of the University nor the names of its contributors |
46 | * may be used to endorse or promote products derived from this software |
47 | * without specific prior written permission. |
48 | * |
49 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
50 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
51 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
52 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
53 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
54 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
55 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
56 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
57 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
58 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
59 | * SUCH DAMAGE. |
60 | * |
61 | * @(#)udp_var.h 8.1 (Berkeley) 6/10/93 |
62 | */ |
63 | |
64 | #include <sys/cdefs.h> |
65 | __KERNEL_RCSID(0, "$NetBSD: udp6_output.c,v 1.54 2016/10/31 04:16:25 ozaki-r Exp $" ); |
66 | |
67 | #ifdef _KERNEL_OPT |
68 | #include "opt_inet.h" |
69 | #endif |
70 | |
71 | #include <sys/param.h> |
72 | #include <sys/mbuf.h> |
73 | #include <sys/protosw.h> |
74 | #include <sys/socket.h> |
75 | #include <sys/socketvar.h> |
76 | #include <sys/errno.h> |
77 | #include <sys/stat.h> |
78 | #include <sys/systm.h> |
79 | #include <sys/proc.h> |
80 | #include <sys/syslog.h> |
81 | #include <sys/kauth.h> |
82 | #include <sys/domain.h> |
83 | |
84 | #include <net/if.h> |
85 | #include <net/if_types.h> |
86 | |
87 | #include <netinet/in.h> |
88 | #include <netinet/in_var.h> |
89 | #include <netinet/in_systm.h> |
90 | #include <netinet/ip.h> |
91 | #include <netinet/ip_var.h> |
92 | #include <netinet/in_pcb.h> |
93 | #include <netinet/udp.h> |
94 | #include <netinet/udp_var.h> |
95 | #include <netinet/udp_private.h> |
96 | #include <netinet/ip6.h> |
97 | #include <netinet6/ip6_var.h> |
98 | #include <netinet6/in6_pcb.h> |
99 | #include <netinet6/udp6_var.h> |
100 | #include <netinet6/udp6_private.h> |
101 | #include <netinet/icmp6.h> |
102 | #include <netinet6/ip6protosw.h> |
103 | #include <netinet6/scope6_var.h> |
104 | |
105 | #include "faith.h" |
106 | |
107 | #include <net/net_osdep.h> |
108 | |
109 | /* |
110 | * UDP protocol inplementation. |
111 | * Per RFC 768, August, 1980. |
112 | */ |
113 | |
114 | int |
115 | udp6_output(struct in6pcb * const in6p, struct mbuf *m, |
116 | struct sockaddr_in6 * const addr6, struct mbuf * const control, |
117 | struct lwp * const l) |
118 | { |
119 | u_int32_t ulen = m->m_pkthdr.len; |
120 | u_int32_t plen = sizeof(struct udphdr) + ulen; |
121 | struct ip6_hdr *ip6; |
122 | struct udphdr *udp6; |
123 | struct in6_addr _laddr, *laddr, *faddr; |
124 | struct in6_addr laddr_mapped; /* XXX ugly */ |
125 | struct sockaddr_in6 *sin6 = NULL; |
126 | struct ifnet *oifp = NULL; |
127 | int scope_ambiguous = 0; |
128 | u_int16_t fport; |
129 | int error = 0; |
130 | struct ip6_pktopts *optp = NULL; |
131 | struct ip6_pktopts opt; |
132 | int af = AF_INET6, hlen = sizeof(struct ip6_hdr); |
133 | #ifdef INET |
134 | struct ip *ip; |
135 | struct udpiphdr *ui; |
136 | int flags = 0; |
137 | #endif |
138 | struct sockaddr_in6 tmp; |
139 | |
140 | if (addr6) { |
141 | sin6 = addr6; |
142 | if (sin6->sin6_family != AF_INET6) { |
143 | error = EAFNOSUPPORT; |
144 | goto release; |
145 | } |
146 | |
147 | /* protect *sin6 from overwrites */ |
148 | tmp = *sin6; |
149 | sin6 = &tmp; |
150 | |
151 | /* |
152 | * Application should provide a proper zone ID or the use of |
153 | * default zone IDs should be enabled. Unfortunately, some |
154 | * applications do not behave as it should, so we need a |
155 | * workaround. Even if an appropriate ID is not determined, |
156 | * we'll see if we can determine the outgoing interface. If we |
157 | * can, determine the zone ID based on the interface below. |
158 | */ |
159 | if (sin6->sin6_scope_id == 0 && !ip6_use_defzone) |
160 | scope_ambiguous = 1; |
161 | if ((error = sa6_embedscope(sin6, ip6_use_defzone)) != 0) |
162 | goto release; |
163 | } |
164 | |
165 | if (control) { |
166 | if ((error = ip6_setpktopts(control, &opt, |
167 | in6p->in6p_outputopts, l->l_cred, IPPROTO_UDP)) != 0) |
168 | goto release; |
169 | optp = &opt; |
170 | } else |
171 | optp = in6p->in6p_outputopts; |
172 | |
173 | |
174 | if (sin6) { |
175 | /* |
176 | * Slightly different than v4 version in that we call |
177 | * in6_selectsrc and in6_pcbsetport to fill in the local |
178 | * address and port rather than in_pcbconnect. in_pcbconnect |
179 | * sets in6p_faddr which causes EISCONN below to be hit on |
180 | * subsequent sendto. |
181 | */ |
182 | if (sin6->sin6_port == 0) { |
183 | error = EADDRNOTAVAIL; |
184 | goto release; |
185 | } |
186 | |
187 | if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) { |
188 | /* how about ::ffff:0.0.0.0 case? */ |
189 | error = EISCONN; |
190 | goto release; |
191 | } |
192 | |
193 | |
194 | faddr = &sin6->sin6_addr; |
195 | fport = sin6->sin6_port; /* allow 0 port */ |
196 | |
197 | if (IN6_IS_ADDR_V4MAPPED(faddr)) { |
198 | if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) |
199 | { |
200 | /* |
201 | * I believe we should explicitly discard the |
202 | * packet when mapped addresses are disabled, |
203 | * rather than send the packet as an IPv6 one. |
204 | * If we chose the latter approach, the packet |
205 | * might be sent out on the wire based on the |
206 | * default route, the situation which we'd |
207 | * probably want to avoid. |
208 | * (20010421 jinmei@kame.net) |
209 | */ |
210 | error = EINVAL; |
211 | goto release; |
212 | } |
213 | if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) |
214 | && !IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)) { |
215 | /* |
216 | * when remote addr is an IPv4-mapped address, |
217 | * local addr should not be an IPv6 address, |
218 | * since you cannot determine how to map IPv6 |
219 | * source address to IPv4. |
220 | */ |
221 | error = EINVAL; |
222 | goto release; |
223 | } |
224 | |
225 | af = AF_INET; |
226 | } |
227 | |
228 | if (!IN6_IS_ADDR_V4MAPPED(faddr)) { |
229 | struct psref psref; |
230 | int bound = curlwp_bind(); |
231 | |
232 | error = in6_selectsrc(sin6, optp, |
233 | in6p->in6p_moptions, |
234 | &in6p->in6p_route, |
235 | &in6p->in6p_laddr, &oifp, &psref, &_laddr); |
236 | /* XXX need error check? */ |
237 | if (oifp && scope_ambiguous && |
238 | (error = in6_setscope(&sin6->sin6_addr, |
239 | oifp, NULL))) { |
240 | if_put(oifp, &psref); |
241 | curlwp_bindx(bound); |
242 | goto release; |
243 | } |
244 | if_put(oifp, &psref); |
245 | curlwp_bindx(bound); |
246 | laddr = &_laddr; |
247 | } else { |
248 | /* |
249 | * XXX: freebsd[34] does not have in_selectsrc, but |
250 | * we can omit the whole part because freebsd4 calls |
251 | * udp_output() directly in this case, and thus we'll |
252 | * never see this path. |
253 | */ |
254 | if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) { |
255 | struct sockaddr_in sin_dst; |
256 | struct in_addr ina; |
257 | struct in_ifaddr *ia4; |
258 | struct psref _psref; |
259 | int bound; |
260 | |
261 | memcpy(&ina, &faddr->s6_addr[12], sizeof(ina)); |
262 | sockaddr_in_init(&sin_dst, &ina, 0); |
263 | bound = curlwp_bind(); |
264 | ia4 = in_selectsrc(&sin_dst, &in6p->in6p_route, |
265 | in6p->in6p_socket->so_options, NULL, |
266 | &error, &_psref); |
267 | if (ia4 == NULL) { |
268 | curlwp_bindx(bound); |
269 | if (error == 0) |
270 | error = EADDRNOTAVAIL; |
271 | goto release; |
272 | } |
273 | memset(&laddr_mapped, 0, sizeof(laddr_mapped)); |
274 | laddr_mapped.s6_addr16[5] = 0xffff; /* ugly */ |
275 | memcpy(&laddr_mapped.s6_addr[12], |
276 | &IA_SIN(ia4)->sin_addr, |
277 | sizeof(IA_SIN(ia4)->sin_addr)); |
278 | ia4_release(ia4, &_psref); |
279 | curlwp_bindx(bound); |
280 | laddr = &laddr_mapped; |
281 | } else |
282 | { |
283 | laddr = &in6p->in6p_laddr; /* XXX */ |
284 | } |
285 | } |
286 | if (laddr == NULL) { |
287 | if (error == 0) |
288 | error = EADDRNOTAVAIL; |
289 | goto release; |
290 | } |
291 | if (in6p->in6p_lport == 0) { |
292 | /* |
293 | * Craft a sockaddr_in6 for the local endpoint. Use the |
294 | * "any" as a base, set the address, and recover the |
295 | * scope. |
296 | */ |
297 | struct sockaddr_in6 lsin6 = |
298 | *((const struct sockaddr_in6 *)in6p->in6p_socket->so_proto->pr_domain->dom_sa_any); |
299 | lsin6.sin6_addr = *laddr; |
300 | error = sa6_recoverscope(&lsin6); |
301 | if (error) |
302 | goto release; |
303 | |
304 | error = in6_pcbsetport(&lsin6, in6p, l); |
305 | |
306 | if (error) { |
307 | in6p->in6p_laddr = in6addr_any; |
308 | goto release; |
309 | } |
310 | } |
311 | } else { |
312 | if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) { |
313 | error = ENOTCONN; |
314 | goto release; |
315 | } |
316 | if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) { |
317 | if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) |
318 | { |
319 | /* |
320 | * XXX: this case would happen when the |
321 | * application sets the V6ONLY flag after |
322 | * connecting the foreign address. |
323 | * Such applications should be fixed, |
324 | * so we bark here. |
325 | */ |
326 | log(LOG_INFO, "udp6_output: IPV6_V6ONLY " |
327 | "option was set for a connected socket\n" ); |
328 | error = EINVAL; |
329 | goto release; |
330 | } else |
331 | af = AF_INET; |
332 | } |
333 | laddr = &in6p->in6p_laddr; |
334 | faddr = &in6p->in6p_faddr; |
335 | fport = in6p->in6p_fport; |
336 | } |
337 | |
338 | if (af == AF_INET) |
339 | hlen = sizeof(struct ip); |
340 | |
341 | /* |
342 | * Calculate data length and get a mbuf |
343 | * for UDP and IP6 headers. |
344 | */ |
345 | M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT); |
346 | if (m == 0) { |
347 | error = ENOBUFS; |
348 | goto release; |
349 | } |
350 | |
351 | /* |
352 | * Stuff checksum and output datagram. |
353 | */ |
354 | udp6 = (struct udphdr *)(mtod(m, char *) + hlen); |
355 | udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */ |
356 | udp6->uh_dport = fport; |
357 | if (plen <= 0xffff) |
358 | udp6->uh_ulen = htons((u_int16_t)plen); |
359 | else |
360 | udp6->uh_ulen = 0; |
361 | udp6->uh_sum = 0; |
362 | |
363 | switch (af) { |
364 | case AF_INET6: |
365 | ip6 = mtod(m, struct ip6_hdr *); |
366 | ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK; |
367 | ip6->ip6_vfc &= ~IPV6_VERSION_MASK; |
368 | ip6->ip6_vfc |= IPV6_VERSION; |
369 | #if 0 /* ip6_plen will be filled in ip6_output. */ |
370 | ip6->ip6_plen = htons((u_int16_t)plen); |
371 | #endif |
372 | ip6->ip6_nxt = IPPROTO_UDP; |
373 | ip6->ip6_hlim = in6_selecthlim_rt(in6p); |
374 | ip6->ip6_src = *laddr; |
375 | ip6->ip6_dst = *faddr; |
376 | |
377 | udp6->uh_sum = in6_cksum_phdr(laddr, faddr, |
378 | htonl(plen), htonl(IPPROTO_UDP)); |
379 | m->m_pkthdr.csum_flags = M_CSUM_UDPv6; |
380 | m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); |
381 | |
382 | UDP6_STATINC(UDP6_STAT_OPACKETS); |
383 | error = ip6_output(m, optp, &in6p->in6p_route, 0, |
384 | in6p->in6p_moptions, in6p->in6p_socket, NULL); |
385 | break; |
386 | case AF_INET: |
387 | #ifdef INET |
388 | /* can't transmit jumbogram over IPv4 */ |
389 | if (plen > 0xffff) { |
390 | error = EMSGSIZE; |
391 | goto release; |
392 | } |
393 | |
394 | ip = mtod(m, struct ip *); |
395 | ui = (struct udpiphdr *)ip; |
396 | memset(ui->ui_x1, 0, sizeof(ui->ui_x1)); |
397 | ui->ui_pr = IPPROTO_UDP; |
398 | ui->ui_len = htons(plen); |
399 | memcpy(&ui->ui_src, &laddr->s6_addr[12], sizeof(ui->ui_src)); |
400 | ui->ui_ulen = ui->ui_len; |
401 | |
402 | flags = (in6p->in6p_socket->so_options & |
403 | (SO_DONTROUTE | SO_BROADCAST)); |
404 | memcpy(&ui->ui_dst, &faddr->s6_addr[12], sizeof(ui->ui_dst)); |
405 | |
406 | udp6->uh_sum = in_cksum(m, hlen + plen); |
407 | if (udp6->uh_sum == 0) |
408 | udp6->uh_sum = 0xffff; |
409 | |
410 | ip->ip_len = htons(hlen + plen); |
411 | ip->ip_ttl = in6_selecthlim(in6p, NULL); /* XXX */ |
412 | ip->ip_tos = 0; /* XXX */ |
413 | |
414 | UDP_STATINC(UDP_STAT_OPACKETS); |
415 | error = ip_output(m, NULL, &in6p->in6p_route, flags /* XXX */, |
416 | in6p->in6p_v4moptions, (struct socket *)in6p->in6p_socket); |
417 | break; |
418 | #else |
419 | error = EAFNOSUPPORT; |
420 | goto release; |
421 | #endif |
422 | } |
423 | goto releaseopt; |
424 | |
425 | release: |
426 | m_freem(m); |
427 | |
428 | releaseopt: |
429 | if (control) { |
430 | if (optp == &opt) |
431 | ip6_clearpktopts(&opt, -1); |
432 | m_freem(control); |
433 | } |
434 | return (error); |
435 | } |
436 | |