1 /*-
2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
3 * The Regents of the University of California.
4 * Copyright (c) 2008 Robert N. M. Watson
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 4. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95
32 */
33
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD: releng/8.0/sys/netinet/udp_usrreq.c 196039 2009-08-02 19:43:32Z rwatson $");
36
37 #include "opt_ipfw.h"
38 #include "opt_inet6.h"
39 #include "opt_ipsec.h"
40
41 #include <sys/param.h>
42 #include <sys/domain.h>
43 #include <sys/eventhandler.h>
44 #include <sys/jail.h>
45 #include <sys/kernel.h>
46 #include <sys/lock.h>
47 #include <sys/malloc.h>
48 #include <sys/mbuf.h>
49 #include <sys/priv.h>
50 #include <sys/proc.h>
51 #include <sys/protosw.h>
52 #include <sys/signalvar.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55 #include <sys/sx.h>
56 #include <sys/sysctl.h>
57 #include <sys/syslog.h>
58 #include <sys/systm.h>
59
60 #include <vm/uma.h>
61
62 #include <net/if.h>
63 #include <net/route.h>
64
65 #include <netinet/in.h>
66 #include <netinet/in_pcb.h>
67 #include <netinet/in_systm.h>
68 #include <netinet/in_var.h>
69 #include <netinet/ip.h>
70 #ifdef INET6
71 #include <netinet/ip6.h>
72 #endif
73 #include <netinet/ip_icmp.h>
74 #include <netinet/icmp_var.h>
75 #include <netinet/ip_var.h>
76 #include <netinet/ip_options.h>
77 #ifdef INET6
78 #include <netinet6/ip6_var.h>
79 #endif
80 #include <netinet/udp.h>
81 #include <netinet/udp_var.h>
82
83 #ifdef IPSEC
84 #include <netipsec/ipsec.h>
85 #include <netipsec/esp.h>
86 #endif
87
88 #include <machine/in_cksum.h>
89
90 #include <security/mac/mac_framework.h>
91
92 /*
93 * UDP protocol implementation.
94 * Per RFC 768, August, 1980.
95 */
96
97 VNET_DEFINE(int, udp_blackhole);
98
99 /*
100 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums
101 * removes the only data integrity mechanism for packets and malformed
102 * packets that would otherwise be discarded due to bad checksums, and may
103 * cause problems (especially for NFS data blocks).
104 */
105 static int udp_cksum = 1;
106 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, &udp_cksum,
107 0, "compute udp checksum");
108
109 int udp_log_in_vain = 0;
110 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
111 &udp_log_in_vain, 0, "Log all incoming UDP packets");
112
113 SYSCTL_VNET_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW,
114 &VNET_NAME(udp_blackhole), 0,
115 "Do not send port unreachables for refused connects");
116
117 u_long udp_sendspace = 9216; /* really max datagram size */
118 /* 40 1K datagrams */
119 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
120 &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
121
122 u_long udp_recvspace = 40 * (1024 +
123 #ifdef INET6
124 sizeof(struct sockaddr_in6)
125 #else
126 sizeof(struct sockaddr_in)
127 #endif
128 );
129
130 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
131 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
132
133 VNET_DEFINE(struct inpcbhead, udb); /* from udp_var.h */
134 VNET_DEFINE(struct inpcbinfo, udbinfo);
135 static VNET_DEFINE(uma_zone_t, udpcb_zone);
136 VNET_DEFINE(struct udpstat, udpstat); /* from udp_var.h */
137
138 #define V_udpcb_zone VNET(udpcb_zone)
139
140 #ifndef UDBHASHSIZE
141 #define UDBHASHSIZE 128
142 #endif
143
144 SYSCTL_VNET_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW,
145 &VNET_NAME(udpstat), udpstat,
146 "UDP statistics (struct udpstat, netinet/udp_var.h)");
147
148 static void udp_detach(struct socket *so);
149 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
150 struct mbuf *, struct thread *);
151 #ifdef IPSEC
152 #ifdef IPSEC_NAT_T
153 #define UF_ESPINUDP_ALL (UF_ESPINUDP_NON_IKE|UF_ESPINUDP)
154 #ifdef INET
155 static struct mbuf *udp4_espdecap(struct inpcb *, struct mbuf *, int);
156 #endif
157 #endif /* IPSEC_NAT_T */
158 #endif /* IPSEC */
159
160 static void
161 udp_zone_change(void *tag)
162 {
163
164 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
165 uma_zone_set_max(V_udpcb_zone, maxsockets);
166 }
167
168 static int
169 udp_inpcb_init(void *mem, int size, int flags)
170 {
171 struct inpcb *inp;
172
173 inp = mem;
174 INP_LOCK_INIT(inp, "inp", "udpinp");
175 return (0);
176 }
177
178 void
179 udp_init(void)
180 {
181
182 V_udp_blackhole = 0;
183
184 INP_INFO_LOCK_INIT(&V_udbinfo, "udp");
185 LIST_INIT(&V_udb);
186 #ifdef VIMAGE
187 V_udbinfo.ipi_vnet = curvnet;
188 #endif
189 V_udbinfo.ipi_listhead = &V_udb;
190 V_udbinfo.ipi_hashbase = hashinit(UDBHASHSIZE, M_PCB,
191 &V_udbinfo.ipi_hashmask);
192 V_udbinfo.ipi_porthashbase = hashinit(UDBHASHSIZE, M_PCB,
193 &V_udbinfo.ipi_porthashmask);
194 V_udbinfo.ipi_zone = uma_zcreate("udp_inpcb", sizeof(struct inpcb),
195 NULL, NULL, udp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
196 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
197
198 V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb),
199 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
200 uma_zone_set_max(V_udpcb_zone, maxsockets);
201
202 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
203 EVENTHANDLER_PRI_ANY);
204 }
205
206 /*
207 * Kernel module interface for updating udpstat. The argument is an index
208 * into udpstat treated as an array of u_long. While this encodes the
209 * general layout of udpstat into the caller, it doesn't encode its location,
210 * so that future changes to add, for example, per-CPU stats support won't
211 * cause binary compatibility problems for kernel modules.
212 */
213 void
214 kmod_udpstat_inc(int statnum)
215 {
216
217 (*((u_long *)&V_udpstat + statnum))++;
218 }
219
220 int
221 udp_newudpcb(struct inpcb *inp)
222 {
223 struct udpcb *up;
224
225 up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO);
226 if (up == NULL)
227 return (ENOBUFS);
228 inp->inp_ppcb = up;
229 return (0);
230 }
231
232 void
233 udp_discardcb(struct udpcb *up)
234 {
235
236 uma_zfree(V_udpcb_zone, up);
237 }
238
239 #ifdef VIMAGE
240 void
241 udp_destroy(void)
242 {
243
244 hashdestroy(V_udbinfo.ipi_hashbase, M_PCB,
245 V_udbinfo.ipi_hashmask);
246 hashdestroy(V_udbinfo.ipi_porthashbase, M_PCB,
247 V_udbinfo.ipi_porthashmask);
248 INP_INFO_LOCK_DESTROY(&V_udbinfo);
249 }
250 #endif
251
252 /*
253 * Subroutine of udp_input(), which appends the provided mbuf chain to the
254 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that
255 * contains the source address. If the socket ends up being an IPv6 socket,
256 * udp_append() will convert to a sockaddr_in6 before passing the address
257 * into the socket code.
258 */
259 static void
260 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
261 struct sockaddr_in *udp_in)
262 {
263 struct sockaddr *append_sa;
264 struct socket *so;
265 struct mbuf *opts = 0;
266 #ifdef INET6
267 struct sockaddr_in6 udp_in6;
268 #endif
269 #ifdef IPSEC
270 #ifdef IPSEC_NAT_T
271 #ifdef INET
272 struct udpcb *up;
273 #endif
274 #endif
275 #endif
276
277 INP_RLOCK_ASSERT(inp);
278
279 #ifdef IPSEC
280 /* Check AH/ESP integrity. */
281 if (ipsec4_in_reject(n, inp)) {
282 m_freem(n);
283 V_ipsec4stat.in_polvio++;
284 return;
285 }
286 #ifdef IPSEC_NAT_T
287 #ifdef INET
288 up = intoudpcb(inp);
289 KASSERT(up != NULL, ("%s: udpcb NULL", __func__));
290 if (up->u_flags & UF_ESPINUDP_ALL) { /* IPSec UDP encaps. */
291 n = udp4_espdecap(inp, n, off);
292 if (n == NULL) /* Consumed. */
293 return;
294 }
295 #endif /* INET */
296 #endif /* IPSEC_NAT_T */
297 #endif /* IPSEC */
298 #ifdef MAC
299 if (mac_inpcb_check_deliver(inp, n) != 0) {
300 m_freem(n);
301 return;
302 }
303 #endif
304 if (inp->inp_flags & INP_CONTROLOPTS ||
305 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
306 #ifdef INET6
307 if (inp->inp_vflag & INP_IPV6)
308 (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
309 else
310 #endif
311 ip_savecontrol(inp, &opts, ip, n);
312 }
313 #ifdef INET6
314 if (inp->inp_vflag & INP_IPV6) {
315 bzero(&udp_in6, sizeof(udp_in6));
316 udp_in6.sin6_len = sizeof(udp_in6);
317 udp_in6.sin6_family = AF_INET6;
318 in6_sin_2_v4mapsin6(udp_in, &udp_in6);
319 append_sa = (struct sockaddr *)&udp_in6;
320 } else
321 #endif
322 append_sa = (struct sockaddr *)udp_in;
323 m_adj(n, off);
324
325 so = inp->inp_socket;
326 SOCKBUF_LOCK(&so->so_rcv);
327 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
328 SOCKBUF_UNLOCK(&so->so_rcv);
329 m_freem(n);
330 if (opts)
331 m_freem(opts);
332 UDPSTAT_INC(udps_fullsock);
333 } else
334 sorwakeup_locked(so);
335 }
336
337 void
338 udp_input(struct mbuf *m, int off)
339 {
340 int iphlen = off;
341 struct ip *ip;
342 struct udphdr *uh;
343 struct ifnet *ifp;
344 struct inpcb *inp;
345 struct udpcb *up;
346 int len;
347 struct ip save_ip;
348 struct sockaddr_in udp_in;
349 #ifdef IPFIREWALL_FORWARD
350 struct m_tag *fwd_tag;
351 #endif
352
353 ifp = m->m_pkthdr.rcvif;
354 UDPSTAT_INC(udps_ipackets);
355
356 /*
357 * Strip IP options, if any; should skip this, make available to
358 * user, and use on returned packets, but we don't yet have a way to
359 * check the checksum with options still present.
360 */
361 if (iphlen > sizeof (struct ip)) {
362 ip_stripoptions(m, (struct mbuf *)0);
363 iphlen = sizeof(struct ip);
364 }
365
366 /*
367 * Get IP and UDP header together in first mbuf.
368 */
369 ip = mtod(m, struct ip *);
370 if (m->m_len < iphlen + sizeof(struct udphdr)) {
371 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) {
372 UDPSTAT_INC(udps_hdrops);
373 return;
374 }
375 ip = mtod(m, struct ip *);
376 }
377 uh = (struct udphdr *)((caddr_t)ip + iphlen);
378
379 /*
380 * Destination port of 0 is illegal, based on RFC768.
381 */
382 if (uh->uh_dport == 0)
383 goto badunlocked;
384
385 /*
386 * Construct sockaddr format source address. Stuff source address
387 * and datagram in user buffer.
388 */
389 bzero(&udp_in, sizeof(udp_in));
390 udp_in.sin_len = sizeof(udp_in);
391 udp_in.sin_family = AF_INET;
392 udp_in.sin_port = uh->uh_sport;
393 udp_in.sin_addr = ip->ip_src;
394
395 /*
396 * Make mbuf data length reflect UDP length. If not enough data to
397 * reflect UDP length, drop.
398 */
399 len = ntohs((u_short)uh->uh_ulen);
400 if (ip->ip_len != len) {
401 if (len > ip->ip_len || len < sizeof(struct udphdr)) {
402 UDPSTAT_INC(udps_badlen);
403 goto badunlocked;
404 }
405 m_adj(m, len - ip->ip_len);
406 /* ip->ip_len = len; */
407 }
408
409 /*
410 * Save a copy of the IP header in case we want restore it for
411 * sending an ICMP error message in response.
412 */
413 if (!V_udp_blackhole)
414 save_ip = *ip;
415 else
416 memset(&save_ip, 0, sizeof(save_ip));
417
418 /*
419 * Checksum extended UDP header and data.
420 */
421 if (uh->uh_sum) {
422 u_short uh_sum;
423
424 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
425 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
426 uh_sum = m->m_pkthdr.csum_data;
427 else
428 uh_sum = in_pseudo(ip->ip_src.s_addr,
429 ip->ip_dst.s_addr, htonl((u_short)len +
430 m->m_pkthdr.csum_data + IPPROTO_UDP));
431 uh_sum ^= 0xffff;
432 } else {
433 char b[9];
434
435 bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
436 bzero(((struct ipovly *)ip)->ih_x1, 9);
437 ((struct ipovly *)ip)->ih_len = uh->uh_ulen;
438 uh_sum = in_cksum(m, len + sizeof (struct ip));
439 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
440 }
441 if (uh_sum) {
442 UDPSTAT_INC(udps_badsum);
443 m_freem(m);
444 return;
445 }
446 } else
447 UDPSTAT_INC(udps_nosum);
448
449 #ifdef IPFIREWALL_FORWARD
450 /*
451 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
452 */
453 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
454 if (fwd_tag != NULL) {
455 struct sockaddr_in *next_hop;
456
457 /*
458 * Do the hack.
459 */
460 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
461 ip->ip_dst = next_hop->sin_addr;
462 uh->uh_dport = ntohs(next_hop->sin_port);
463
464 /*
465 * Remove the tag from the packet. We don't need it anymore.
466 */
467 m_tag_delete(m, fwd_tag);
468 }
469 #endif
470
471 INP_INFO_RLOCK(&V_udbinfo);
472 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
473 in_broadcast(ip->ip_dst, ifp)) {
474 struct inpcb *last;
475 struct ip_moptions *imo;
476
477 last = NULL;
478 LIST_FOREACH(inp, &V_udb, inp_list) {
479 if (inp->inp_lport != uh->uh_dport)
480 continue;
481 #ifdef INET6
482 if ((inp->inp_vflag & INP_IPV4) == 0)
483 continue;
484 #endif
485 if (inp->inp_laddr.s_addr != INADDR_ANY &&
486 inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
487 continue;
488 if (inp->inp_faddr.s_addr != INADDR_ANY &&
489 inp->inp_faddr.s_addr != ip->ip_src.s_addr)
490 continue;
491 if (inp->inp_fport != 0 &&
492 inp->inp_fport != uh->uh_sport)
493 continue;
494
495 INP_RLOCK(inp);
496
497 /*
498 * Handle socket delivery policy for any-source
499 * and source-specific multicast. [RFC3678]
500 */
501 imo = inp->inp_moptions;
502 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
503 imo != NULL) {
504 struct sockaddr_in group;
505 int blocked;
506
507 bzero(&group, sizeof(struct sockaddr_in));
508 group.sin_len = sizeof(struct sockaddr_in);
509 group.sin_family = AF_INET;
510 group.sin_addr = ip->ip_dst;
511
512 blocked = imo_multi_filter(imo, ifp,
513 (struct sockaddr *)&group,
514 (struct sockaddr *)&udp_in);
515 if (blocked != MCAST_PASS) {
516 if (blocked == MCAST_NOTGMEMBER)
517 IPSTAT_INC(ips_notmember);
518 if (blocked == MCAST_NOTSMEMBER ||
519 blocked == MCAST_MUTED)
520 UDPSTAT_INC(udps_filtermcast);
521 INP_RUNLOCK(inp);
522 continue;
523 }
524 }
525 if (last != NULL) {
526 struct mbuf *n;
527
528 n = m_copy(m, 0, M_COPYALL);
529 up = intoudpcb(last);
530 if (up->u_tun_func == NULL) {
531 if (n != NULL)
532 udp_append(last,
533 ip, n,
534 iphlen +
535 sizeof(struct udphdr),
536 &udp_in);
537 } else {
538 /*
539 * Engage the tunneling protocol we
540 * will have to leave the info_lock
541 * up, since we are hunting through
542 * multiple UDP's.
543 */
544
545 (*up->u_tun_func)(n, iphlen, last);
546 }
547 INP_RUNLOCK(last);
548 }
549 last = inp;
550 /*
551 * Don't look for additional matches if this one does
552 * not have either the SO_REUSEPORT or SO_REUSEADDR
553 * socket options set. This heuristic avoids
554 * searching through all pcbs in the common case of a
555 * non-shared port. It assumes that an application
556 * will never clear these options after setting them.
557 */
558 if ((last->inp_socket->so_options &
559 (SO_REUSEPORT|SO_REUSEADDR)) == 0)
560 break;
561 }
562
563 if (last == NULL) {
564 /*
565 * No matching pcb found; discard datagram. (No need
566 * to send an ICMP Port Unreachable for a broadcast
567 * or multicast datgram.)
568 */
569 UDPSTAT_INC(udps_noportbcast);
570 goto badheadlocked;
571 }
572 up = intoudpcb(last);
573 if (up->u_tun_func == NULL) {
574 udp_append(last, ip, m, iphlen + sizeof(struct udphdr),
575 &udp_in);
576 } else {
577 /*
578 * Engage the tunneling protocol.
579 */
580 (*up->u_tun_func)(m, iphlen, last);
581 }
582 INP_RUNLOCK(last);
583 INP_INFO_RUNLOCK(&V_udbinfo);
584 return;
585 }
586
587 /*
588 * Locate pcb for datagram.
589 */
590 inp = in_pcblookup_hash(&V_udbinfo, ip->ip_src, uh->uh_sport,
591 ip->ip_dst, uh->uh_dport, 1, ifp);
592 if (inp == NULL) {
593 if (udp_log_in_vain) {
594 char buf[4*sizeof "123"];
595
596 strcpy(buf, inet_ntoa(ip->ip_dst));
597 log(LOG_INFO,
598 "Connection attempt to UDP %s:%d from %s:%d\n",
599 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src),
600 ntohs(uh->uh_sport));
601 }
602 UDPSTAT_INC(udps_noport);
603 if (m->m_flags & (M_BCAST | M_MCAST)) {
604 UDPSTAT_INC(udps_noportbcast);
605 goto badheadlocked;
606 }
607 if (V_udp_blackhole)
608 goto badheadlocked;
609 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
610 goto badheadlocked;
611 *ip = save_ip;
612 ip->ip_len += iphlen;
613 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
614 INP_INFO_RUNLOCK(&V_udbinfo);
615 return;
616 }
617
618 /*
619 * Check the minimum TTL for socket.
620 */
621 INP_RLOCK(inp);
622 INP_INFO_RUNLOCK(&V_udbinfo);
623 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
624 INP_RUNLOCK(inp);
625 goto badunlocked;
626 }
627 up = intoudpcb(inp);
628 if (up->u_tun_func == NULL) {
629 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in);
630 } else {
631 /*
632 * Engage the tunneling protocol.
633 */
634
635 (*up->u_tun_func)(m, iphlen, inp);
636 }
637 INP_RUNLOCK(inp);
638 return;
639
640 badheadlocked:
641 if (inp)
642 INP_RUNLOCK(inp);
643 INP_INFO_RUNLOCK(&V_udbinfo);
644 badunlocked:
645 m_freem(m);
646 }
647
648 /*
649 * Notify a udp user of an asynchronous error; just wake up so that they can
650 * collect error status.
651 */
652 struct inpcb *
653 udp_notify(struct inpcb *inp, int errno)
654 {
655
656 /*
657 * While udp_ctlinput() always calls udp_notify() with a read lock
658 * when invoking it directly, in_pcbnotifyall() currently uses write
659 * locks due to sharing code with TCP. For now, accept either a read
660 * or a write lock, but a read lock is sufficient.
661 */
662 INP_LOCK_ASSERT(inp);
663
664 inp->inp_socket->so_error = errno;
665 sorwakeup(inp->inp_socket);
666 sowwakeup(inp->inp_socket);
667 return (inp);
668 }
669
670 void
671 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
672 {
673 struct ip *ip = vip;
674 struct udphdr *uh;
675 struct in_addr faddr;
676 struct inpcb *inp;
677
678 faddr = ((struct sockaddr_in *)sa)->sin_addr;
679 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
680 return;
681
682 /*
683 * Redirects don't need to be handled up here.
684 */
685 if (PRC_IS_REDIRECT(cmd))
686 return;
687
688 /*
689 * Hostdead is ugly because it goes linearly through all PCBs.
690 *
691 * XXX: We never get this from ICMP, otherwise it makes an excellent
692 * DoS attack on machines with many connections.
693 */
694 if (cmd == PRC_HOSTDEAD)
695 ip = NULL;
696 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
697 return;
698 if (ip != NULL) {
699 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
700 INP_INFO_RLOCK(&V_udbinfo);
701 inp = in_pcblookup_hash(&V_udbinfo, faddr, uh->uh_dport,
702 ip->ip_src, uh->uh_sport, 0, NULL);
703 if (inp != NULL) {
704 INP_RLOCK(inp);
705 if (inp->inp_socket != NULL) {
706 udp_notify(inp, inetctlerrmap[cmd]);
707 }
708 INP_RUNLOCK(inp);
709 }
710 INP_INFO_RUNLOCK(&V_udbinfo);
711 } else
712 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd],
713 udp_notify);
714 }
715
716 static int
717 udp_pcblist(SYSCTL_HANDLER_ARGS)
718 {
719 int error, i, n;
720 struct inpcb *inp, **inp_list;
721 inp_gen_t gencnt;
722 struct xinpgen xig;
723
724 /*
725 * The process of preparing the PCB list is too time-consuming and
726 * resource-intensive to repeat twice on every request.
727 */
728 if (req->oldptr == 0) {
729 n = V_udbinfo.ipi_count;
730 req->oldidx = 2 * (sizeof xig)
731 + (n + n/8) * sizeof(struct xinpcb);
732 return (0);
733 }
734
735 if (req->newptr != 0)
736 return (EPERM);
737
738 /*
739 * OK, now we're committed to doing something.
740 */
741 INP_INFO_RLOCK(&V_udbinfo);
742 gencnt = V_udbinfo.ipi_gencnt;
743 n = V_udbinfo.ipi_count;
744 INP_INFO_RUNLOCK(&V_udbinfo);
745
746 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
747 + n * sizeof(struct xinpcb));
748 if (error != 0)
749 return (error);
750
751 xig.xig_len = sizeof xig;
752 xig.xig_count = n;
753 xig.xig_gen = gencnt;
754 xig.xig_sogen = so_gencnt;
755 error = SYSCTL_OUT(req, &xig, sizeof xig);
756 if (error)
757 return (error);
758
759 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
760 if (inp_list == 0)
761 return (ENOMEM);
762
763 INP_INFO_RLOCK(&V_udbinfo);
764 for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
765 inp = LIST_NEXT(inp, inp_list)) {
766 INP_RLOCK(inp);
767 if (inp->inp_gencnt <= gencnt &&
768 cr_canseeinpcb(req->td->td_ucred, inp) == 0)
769 inp_list[i++] = inp;
770 INP_RUNLOCK(inp);
771 }
772 INP_INFO_RUNLOCK(&V_udbinfo);
773 n = i;
774
775 error = 0;
776 for (i = 0; i < n; i++) {
777 inp = inp_list[i];
778 INP_RLOCK(inp);
779 if (inp->inp_gencnt <= gencnt) {
780 struct xinpcb xi;
781 bzero(&xi, sizeof(xi));
782 xi.xi_len = sizeof xi;
783 /* XXX should avoid extra copy */
784 bcopy(inp, &xi.xi_inp, sizeof *inp);
785 if (inp->inp_socket)
786 sotoxsocket(inp->inp_socket, &xi.xi_socket);
787 xi.xi_inp.inp_gencnt = inp->inp_gencnt;
788 INP_RUNLOCK(inp);
789 error = SYSCTL_OUT(req, &xi, sizeof xi);
790 } else
791 INP_RUNLOCK(inp);
792 }
793 if (!error) {
794 /*
795 * Give the user an updated idea of our state. If the
796 * generation differs from what we told her before, she knows
797 * that something happened while we were processing this
798 * request, and it might be necessary to retry.
799 */
800 INP_INFO_RLOCK(&V_udbinfo);
801 xig.xig_gen = V_udbinfo.ipi_gencnt;
802 xig.xig_sogen = so_gencnt;
803 xig.xig_count = V_udbinfo.ipi_count;
804 INP_INFO_RUNLOCK(&V_udbinfo);
805 error = SYSCTL_OUT(req, &xig, sizeof xig);
806 }
807 free(inp_list, M_TEMP);
808 return (error);
809 }
810
811 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0,
812 udp_pcblist, "S,xinpcb", "List of active UDP sockets");
813
814 static int
815 udp_getcred(SYSCTL_HANDLER_ARGS)
816 {
817 struct xucred xuc;
818 struct sockaddr_in addrs[2];
819 struct inpcb *inp;
820 int error;
821
822 error = priv_check(req->td, PRIV_NETINET_GETCRED);
823 if (error)
824 return (error);
825 error = SYSCTL_IN(req, addrs, sizeof(addrs));
826 if (error)
827 return (error);
828 INP_INFO_RLOCK(&V_udbinfo);
829 inp = in_pcblookup_hash(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
830 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL);
831 if (inp != NULL) {
832 INP_RLOCK(inp);
833 INP_INFO_RUNLOCK(&V_udbinfo);
834 if (inp->inp_socket == NULL)
835 error = ENOENT;
836 if (error == 0)
837 error = cr_canseeinpcb(req->td->td_ucred, inp);
838 if (error == 0)
839 cru2x(inp->inp_cred, &xuc);
840 INP_RUNLOCK(inp);
841 } else {
842 INP_INFO_RUNLOCK(&V_udbinfo);
843 error = ENOENT;
844 }
845 if (error == 0)
846 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
847 return (error);
848 }
849
850 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
851 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
852 udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
853
854 int
855 udp_ctloutput(struct socket *so, struct sockopt *sopt)
856 {
857 int error = 0, optval;
858 struct inpcb *inp;
859 #ifdef IPSEC_NAT_T
860 struct udpcb *up;
861 #endif
862
863 inp = sotoinpcb(so);
864 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
865 INP_WLOCK(inp);
866 if (sopt->sopt_level != IPPROTO_UDP) {
867 #ifdef INET6
868 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
869 INP_WUNLOCK(inp);
870 error = ip6_ctloutput(so, sopt);
871 } else {
872 #endif
873 INP_WUNLOCK(inp);
874 error = ip_ctloutput(so, sopt);
875 #ifdef INET6
876 }
877 #endif
878 return (error);
879 }
880
881 switch (sopt->sopt_dir) {
882 case SOPT_SET:
883 switch (sopt->sopt_name) {
884 case UDP_ENCAP:
885 INP_WUNLOCK(inp);
886 error = sooptcopyin(sopt, &optval, sizeof optval,
887 sizeof optval);
888 if (error)
889 break;
890 inp = sotoinpcb(so);
891 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
892 INP_WLOCK(inp);
893 #ifdef IPSEC_NAT_T
894 up = intoudpcb(inp);
895 KASSERT(up != NULL, ("%s: up == NULL", __func__));
896 #endif
897 switch (optval) {
898 case 0:
899 /* Clear all UDP encap. */
900 #ifdef IPSEC_NAT_T
901 up->u_flags &= ~UF_ESPINUDP_ALL;
902 #endif
903 break;
904 #ifdef IPSEC_NAT_T
905 case UDP_ENCAP_ESPINUDP:
906 case UDP_ENCAP_ESPINUDP_NON_IKE:
907 up->u_flags &= ~UF_ESPINUDP_ALL;
908 if (optval == UDP_ENCAP_ESPINUDP)
909 up->u_flags |= UF_ESPINUDP;
910 else if (optval == UDP_ENCAP_ESPINUDP_NON_IKE)
911 up->u_flags |= UF_ESPINUDP_NON_IKE;
912 break;
913 #endif
914 default:
915 error = EINVAL;
916 break;
917 }
918 INP_WUNLOCK(inp);
919 break;
920 default:
921 INP_WUNLOCK(inp);
922 error = ENOPROTOOPT;
923 break;
924 }
925 break;
926 case SOPT_GET:
927 switch (sopt->sopt_name) {
928 #ifdef IPSEC_NAT_T
929 case UDP_ENCAP:
930 up = intoudpcb(inp);
931 KASSERT(up != NULL, ("%s: up == NULL", __func__));
932 optval = up->u_flags & UF_ESPINUDP_ALL;
933 INP_WUNLOCK(inp);
934 error = sooptcopyout(sopt, &optval, sizeof optval);
935 break;
936 #endif
937 default:
938 INP_WUNLOCK(inp);
939 error = ENOPROTOOPT;
940 break;
941 }
942 break;
943 }
944 return (error);
945 }
946
947 static int
948 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
949 struct mbuf *control, struct thread *td)
950 {
951 struct udpiphdr *ui;
952 int len = m->m_pkthdr.len;
953 struct in_addr faddr, laddr;
954 struct cmsghdr *cm;
955 struct sockaddr_in *sin, src;
956 int error = 0;
957 int ipflags;
958 u_short fport, lport;
959 int unlock_udbinfo;
960
961 /*
962 * udp_output() may need to temporarily bind or connect the current
963 * inpcb. As such, we don't know up front whether we will need the
964 * pcbinfo lock or not. Do any work to decide what is needed up
965 * front before acquiring any locks.
966 */
967 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
968 if (control)
969 m_freem(control);
970 m_freem(m);
971 return (EMSGSIZE);
972 }
973
974 src.sin_family = 0;
975 if (control != NULL) {
976 /*
977 * XXX: Currently, we assume all the optional information is
978 * stored in a single mbuf.
979 */
980 if (control->m_next) {
981 m_freem(control);
982 m_freem(m);
983 return (EINVAL);
984 }
985 for (; control->m_len > 0;
986 control->m_data += CMSG_ALIGN(cm->cmsg_len),
987 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
988 cm = mtod(control, struct cmsghdr *);
989 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
990 || cm->cmsg_len > control->m_len) {
991 error = EINVAL;
992 break;
993 }
994 if (cm->cmsg_level != IPPROTO_IP)
995 continue;
996
997 switch (cm->cmsg_type) {
998 case IP_SENDSRCADDR:
999 if (cm->cmsg_len !=
1000 CMSG_LEN(sizeof(struct in_addr))) {
1001 error = EINVAL;
1002 break;
1003 }
1004 bzero(&src, sizeof(src));
1005 src.sin_family = AF_INET;
1006 src.sin_len = sizeof(src);
1007 src.sin_port = inp->inp_lport;
1008 src.sin_addr =
1009 *(struct in_addr *)CMSG_DATA(cm);
1010 break;
1011
1012 default:
1013 error = ENOPROTOOPT;
1014 break;
1015 }
1016 if (error)
1017 break;
1018 }
1019 m_freem(control);
1020 }
1021 if (error) {
1022 m_freem(m);
1023 return (error);
1024 }
1025
1026 /*
1027 * Depending on whether or not the application has bound or connected
1028 * the socket, we may have to do varying levels of work. The optimal
1029 * case is for a connected UDP socket, as a global lock isn't
1030 * required at all.
1031 *
1032 * In order to decide which we need, we require stability of the
1033 * inpcb binding, which we ensure by acquiring a read lock on the
1034 * inpcb. This doesn't strictly follow the lock order, so we play
1035 * the trylock and retry game; note that we may end up with more
1036 * conservative locks than required the second time around, so later
1037 * assertions have to accept that. Further analysis of the number of
1038 * misses under contention is required.
1039 */
1040 sin = (struct sockaddr_in *)addr;
1041 INP_RLOCK(inp);
1042 if (sin != NULL &&
1043 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1044 INP_RUNLOCK(inp);
1045 INP_INFO_WLOCK(&V_udbinfo);
1046 INP_WLOCK(inp);
1047 unlock_udbinfo = 2;
1048 } else if ((sin != NULL && (
1049 (sin->sin_addr.s_addr == INADDR_ANY) ||
1050 (sin->sin_addr.s_addr == INADDR_BROADCAST) ||
1051 (inp->inp_laddr.s_addr == INADDR_ANY) ||
1052 (inp->inp_lport == 0))) ||
1053 (src.sin_family == AF_INET)) {
1054 if (!INP_INFO_TRY_RLOCK(&V_udbinfo)) {
1055 INP_RUNLOCK(inp);
1056 INP_INFO_RLOCK(&V_udbinfo);
1057 INP_RLOCK(inp);
1058 }
1059 unlock_udbinfo = 1;
1060 } else
1061 unlock_udbinfo = 0;
1062
1063 /*
1064 * If the IP_SENDSRCADDR control message was specified, override the
1065 * source address for this datagram. Its use is invalidated if the
1066 * address thus specified is incomplete or clobbers other inpcbs.
1067 */
1068 laddr = inp->inp_laddr;
1069 lport = inp->inp_lport;
1070 if (src.sin_family == AF_INET) {
1071 INP_INFO_LOCK_ASSERT(&V_udbinfo);
1072 if ((lport == 0) ||
1073 (laddr.s_addr == INADDR_ANY &&
1074 src.sin_addr.s_addr == INADDR_ANY)) {
1075 error = EINVAL;
1076 goto release;
1077 }
1078 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1079 &laddr.s_addr, &lport, td->td_ucred);
1080 if (error)
1081 goto release;
1082 }
1083
1084 /*
1085 * If a UDP socket has been connected, then a local address/port will
1086 * have been selected and bound.
1087 *
1088 * If a UDP socket has not been connected to, then an explicit
1089 * destination address must be used, in which case a local
1090 * address/port may not have been selected and bound.
1091 */
1092 if (sin != NULL) {
1093 INP_LOCK_ASSERT(inp);
1094 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1095 error = EISCONN;
1096 goto release;
1097 }
1098
1099 /*
1100 * Jail may rewrite the destination address, so let it do
1101 * that before we use it.
1102 */
1103 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1104 if (error)
1105 goto release;
1106
1107 /*
1108 * If a local address or port hasn't yet been selected, or if
1109 * the destination address needs to be rewritten due to using
1110 * a special INADDR_ constant, invoke in_pcbconnect_setup()
1111 * to do the heavy lifting. Once a port is selected, we
1112 * commit the binding back to the socket; we also commit the
1113 * binding of the address if in jail.
1114 *
1115 * If we already have a valid binding and we're not
1116 * requesting a destination address rewrite, use a fast path.
1117 */
1118 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1119 inp->inp_lport == 0 ||
1120 sin->sin_addr.s_addr == INADDR_ANY ||
1121 sin->sin_addr.s_addr == INADDR_BROADCAST) {
1122 INP_INFO_LOCK_ASSERT(&V_udbinfo);
1123 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1124 &lport, &faddr.s_addr, &fport, NULL,
1125 td->td_ucred);
1126 if (error)
1127 goto release;
1128
1129 /*
1130 * XXXRW: Why not commit the port if the address is
1131 * !INADDR_ANY?
1132 */
1133 /* Commit the local port if newly assigned. */
1134 if (inp->inp_laddr.s_addr == INADDR_ANY &&
1135 inp->inp_lport == 0) {
1136 INP_INFO_WLOCK_ASSERT(&V_udbinfo);
1137 INP_WLOCK_ASSERT(inp);
1138 /*
1139 * Remember addr if jailed, to prevent
1140 * rebinding.
1141 */
1142 if (prison_flag(td->td_ucred, PR_IP4))
1143 inp->inp_laddr = laddr;
1144 inp->inp_lport = lport;
1145 if (in_pcbinshash(inp) != 0) {
1146 inp->inp_lport = 0;
1147 error = EAGAIN;
1148 goto release;
1149 }
1150 inp->inp_flags |= INP_ANONPORT;
1151 }
1152 } else {
1153 faddr = sin->sin_addr;
1154 fport = sin->sin_port;
1155 }
1156 } else {
1157 INP_LOCK_ASSERT(inp);
1158 faddr = inp->inp_faddr;
1159 fport = inp->inp_fport;
1160 if (faddr.s_addr == INADDR_ANY) {
1161 error = ENOTCONN;
1162 goto release;
1163 }
1164 }
1165
1166 /*
1167 * Calculate data length and get a mbuf for UDP, IP, and possible
1168 * link-layer headers. Immediate slide the data pointer back forward
1169 * since we won't use that space at this layer.
1170 */
1171 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT);
1172 if (m == NULL) {
1173 error = ENOBUFS;
1174 goto release;
1175 }
1176 m->m_data += max_linkhdr;
1177 m->m_len -= max_linkhdr;
1178 m->m_pkthdr.len -= max_linkhdr;
1179
1180 /*
1181 * Fill in mbuf with extended UDP header and addresses and length put
1182 * into network format.
1183 */
1184 ui = mtod(m, struct udpiphdr *);
1185 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */
1186 ui->ui_pr = IPPROTO_UDP;
1187 ui->ui_src = laddr;
1188 ui->ui_dst = faddr;
1189 ui->ui_sport = lport;
1190 ui->ui_dport = fport;
1191 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1192
1193 /*
1194 * Set the Don't Fragment bit in the IP header.
1195 */
1196 if (inp->inp_flags & INP_DONTFRAG) {
1197 struct ip *ip;
1198
1199 ip = (struct ip *)&ui->ui_i;
1200 ip->ip_off |= IP_DF;
1201 }
1202
1203 ipflags = 0;
1204 if (inp->inp_socket->so_options & SO_DONTROUTE)
1205 ipflags |= IP_ROUTETOIF;
1206 if (inp->inp_socket->so_options & SO_BROADCAST)
1207 ipflags |= IP_ALLOWBROADCAST;
1208 if (inp->inp_flags & INP_ONESBCAST)
1209 ipflags |= IP_SENDONES;
1210
1211 #ifdef MAC
1212 mac_inpcb_create_mbuf(inp, m);
1213 #endif
1214
1215 /*
1216 * Set up checksum and output datagram.
1217 */
1218 if (udp_cksum) {
1219 if (inp->inp_flags & INP_ONESBCAST)
1220 faddr.s_addr = INADDR_BROADCAST;
1221 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1222 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP));
1223 m->m_pkthdr.csum_flags = CSUM_UDP;
1224 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1225 } else
1226 ui->ui_sum = 0;
1227 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
1228 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */
1229 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */
1230 UDPSTAT_INC(udps_opackets);
1231
1232 if (unlock_udbinfo == 2)
1233 INP_INFO_WUNLOCK(&V_udbinfo);
1234 else if (unlock_udbinfo == 1)
1235 INP_INFO_RUNLOCK(&V_udbinfo);
1236 error = ip_output(m, inp->inp_options, NULL, ipflags,
1237 inp->inp_moptions, inp);
1238 if (unlock_udbinfo == 2)
1239 INP_WUNLOCK(inp);
1240 else
1241 INP_RUNLOCK(inp);
1242 return (error);
1243
1244 release:
1245 if (unlock_udbinfo == 2) {
1246 INP_WUNLOCK(inp);
1247 INP_INFO_WUNLOCK(&V_udbinfo);
1248 } else if (unlock_udbinfo == 1) {
1249 INP_RUNLOCK(inp);
1250 INP_INFO_RUNLOCK(&V_udbinfo);
1251 } else
1252 INP_RUNLOCK(inp);
1253 m_freem(m);
1254 return (error);
1255 }
1256
1257
1258 #if defined(IPSEC) && defined(IPSEC_NAT_T)
1259 #ifdef INET
1260 /*
1261 * Potentially decap ESP in UDP frame. Check for an ESP header
1262 * and optional marker; if present, strip the UDP header and
1263 * push the result through IPSec.
1264 *
1265 * Returns mbuf to be processed (potentially re-allocated) or
1266 * NULL if consumed and/or processed.
1267 */
1268 static struct mbuf *
1269 udp4_espdecap(struct inpcb *inp, struct mbuf *m, int off)
1270 {
1271 size_t minlen, payload, skip, iphlen;
1272 caddr_t data;
1273 struct udpcb *up;
1274 struct m_tag *tag;
1275 struct udphdr *udphdr;
1276 struct ip *ip;
1277
1278 INP_RLOCK_ASSERT(inp);
1279
1280 /*
1281 * Pull up data so the longest case is contiguous:
1282 * IP/UDP hdr + non ESP marker + ESP hdr.
1283 */
1284 minlen = off + sizeof(uint64_t) + sizeof(struct esp);
1285 if (minlen > m->m_pkthdr.len)
1286 minlen = m->m_pkthdr.len;
1287 if ((m = m_pullup(m, minlen)) == NULL) {
1288 V_ipsec4stat.in_inval++;
1289 return (NULL); /* Bypass caller processing. */
1290 }
1291 data = mtod(m, caddr_t); /* Points to ip header. */
1292 payload = m->m_len - off; /* Size of payload. */
1293
1294 if (payload == 1 && data[off] == '\xff')
1295 return (m); /* NB: keepalive packet, no decap. */
1296
1297 up = intoudpcb(inp);
1298 KASSERT(up != NULL, ("%s: udpcb NULL", __func__));
1299 KASSERT((up->u_flags & UF_ESPINUDP_ALL) != 0,
1300 ("u_flags 0x%x", up->u_flags));
1301
1302 /*
1303 * Check that the payload is large enough to hold an
1304 * ESP header and compute the amount of data to remove.
1305 *
1306 * NB: the caller has already done a pullup for us.
1307 * XXX can we assume alignment and eliminate bcopys?
1308 */
1309 if (up->u_flags & UF_ESPINUDP_NON_IKE) {
1310 /*
1311 * draft-ietf-ipsec-nat-t-ike-0[01].txt and
1312 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, ignoring
1313 * possible AH mode non-IKE marker+non-ESP marker
1314 * from draft-ietf-ipsec-udp-encaps-00.txt.
1315 */
1316 uint64_t marker;
1317
1318 if (payload <= sizeof(uint64_t) + sizeof(struct esp))
1319 return (m); /* NB: no decap. */
1320 bcopy(data + off, &marker, sizeof(uint64_t));
1321 if (marker != 0) /* Non-IKE marker. */
1322 return (m); /* NB: no decap. */
1323 skip = sizeof(uint64_t) + sizeof(struct udphdr);
1324 } else {
1325 uint32_t spi;
1326
1327 if (payload <= sizeof(struct esp)) {
1328 V_ipsec4stat.in_inval++;
1329 m_freem(m);
1330 return (NULL); /* Discard. */
1331 }
1332 bcopy(data + off, &spi, sizeof(uint32_t));
1333 if (spi == 0) /* Non-ESP marker. */
1334 return (m); /* NB: no decap. */
1335 skip = sizeof(struct udphdr);
1336 }
1337
1338 /*
1339 * Setup a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember
1340 * the UDP ports. This is required if we want to select
1341 * the right SPD for multiple hosts behind same NAT.
1342 *
1343 * NB: ports are maintained in network byte order everywhere
1344 * in the NAT-T code.
1345 */
1346 tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS,
1347 2 * sizeof(uint16_t), M_NOWAIT);
1348 if (tag == NULL) {
1349 V_ipsec4stat.in_nomem++;
1350 m_freem(m);
1351 return (NULL); /* Discard. */
1352 }
1353 iphlen = off - sizeof(struct udphdr);
1354 udphdr = (struct udphdr *)(data + iphlen);
1355 ((uint16_t *)(tag + 1))[0] = udphdr->uh_sport;
1356 ((uint16_t *)(tag + 1))[1] = udphdr->uh_dport;
1357 m_tag_prepend(m, tag);
1358
1359 /*
1360 * Remove the UDP header (and possibly the non ESP marker)
1361 * IP header length is iphlen
1362 * Before:
1363 * <--- off --->
1364 * +----+------+-----+
1365 * | IP | UDP | ESP |
1366 * +----+------+-----+
1367 * <-skip->
1368 * After:
1369 * +----+-----+
1370 * | IP | ESP |
1371 * +----+-----+
1372 * <-skip->
1373 */
1374 ovbcopy(data, data + skip, iphlen);
1375 m_adj(m, skip);
1376
1377 ip = mtod(m, struct ip *);
1378 ip->ip_len -= skip;
1379 ip->ip_p = IPPROTO_ESP;
1380
1381 /*
1382 * We cannot yet update the cksums so clear any
1383 * h/w cksum flags as they are no longer valid.
1384 */
1385 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID)
1386 m->m_pkthdr.csum_flags &= ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR);
1387
1388 (void) ipsec4_common_input(m, iphlen, ip->ip_p);
1389 return (NULL); /* NB: consumed, bypass processing. */
1390 }
1391 #endif /* INET */
1392 #endif /* defined(IPSEC) && defined(IPSEC_NAT_T) */
1393
1394 static void
1395 udp_abort(struct socket *so)
1396 {
1397 struct inpcb *inp;
1398
1399 inp = sotoinpcb(so);
1400 KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1401 INP_INFO_WLOCK(&V_udbinfo);
1402 INP_WLOCK(inp);
1403 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1404 in_pcbdisconnect(inp);
1405 inp->inp_laddr.s_addr = INADDR_ANY;
1406 soisdisconnected(so);
1407 }
1408 INP_WUNLOCK(inp);
1409 INP_INFO_WUNLOCK(&V_udbinfo);
1410 }
1411
1412 static int
1413 udp_attach(struct socket *so, int proto, struct thread *td)
1414 {
1415 struct inpcb *inp;
1416 int error;
1417
1418 inp = sotoinpcb(so);
1419 KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1420 error = soreserve(so, udp_sendspace, udp_recvspace);
1421 if (error)
1422 return (error);
1423 INP_INFO_WLOCK(&V_udbinfo);
1424 error = in_pcballoc(so, &V_udbinfo);
1425 if (error) {
1426 INP_INFO_WUNLOCK(&V_udbinfo);
1427 return (error);
1428 }
1429
1430 inp = (struct inpcb *)so->so_pcb;
1431 inp->inp_vflag |= INP_IPV4;
1432 inp->inp_ip_ttl = V_ip_defttl;
1433
1434 error = udp_newudpcb(inp);
1435 if (error) {
1436 in_pcbdetach(inp);
1437 in_pcbfree(inp);
1438 INP_INFO_WUNLOCK(&V_udbinfo);
1439 return (error);
1440 }
1441
1442 INP_WUNLOCK(inp);
1443 INP_INFO_WUNLOCK(&V_udbinfo);
1444 return (0);
1445 }
1446
1447 int
1448 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f)
1449 {
1450 struct inpcb *inp;
1451 struct udpcb *up;
1452
1453 KASSERT(so->so_type == SOCK_DGRAM, ("udp_set_kernel_tunneling: !dgram"));
1454 KASSERT(so->so_pcb != NULL, ("udp_set_kernel_tunneling: NULL inp"));
1455 if (so->so_type != SOCK_DGRAM) {
1456 /* Not UDP socket... sorry! */
1457 return (ENOTSUP);
1458 }
1459 inp = (struct inpcb *)so->so_pcb;
1460 if (inp == NULL) {
1461 /* NULL INP? */
1462 return (EINVAL);
1463 }
1464 INP_WLOCK(inp);
1465 up = intoudpcb(inp);
1466 if (up->u_tun_func != NULL) {
1467 INP_WUNLOCK(inp);
1468 return (EBUSY);
1469 }
1470 up->u_tun_func = f;
1471 INP_WUNLOCK(inp);
1472 return (0);
1473 }
1474
1475 static int
1476 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1477 {
1478 struct inpcb *inp;
1479 int error;
1480
1481 inp = sotoinpcb(so);
1482 KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1483 INP_INFO_WLOCK(&V_udbinfo);
1484 INP_WLOCK(inp);
1485 error = in_pcbbind(inp, nam, td->td_ucred);
1486 INP_WUNLOCK(inp);
1487 INP_INFO_WUNLOCK(&V_udbinfo);
1488 return (error);
1489 }
1490
1491 static void
1492 udp_close(struct socket *so)
1493 {
1494 struct inpcb *inp;
1495
1496 inp = sotoinpcb(so);
1497 KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1498 INP_INFO_WLOCK(&V_udbinfo);
1499 INP_WLOCK(inp);
1500 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1501 in_pcbdisconnect(inp);
1502 inp->inp_laddr.s_addr = INADDR_ANY;
1503 soisdisconnected(so);
1504 }
1505 INP_WUNLOCK(inp);
1506 INP_INFO_WUNLOCK(&V_udbinfo);
1507 }
1508
1509 static int
1510 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1511 {
1512 struct inpcb *inp;
1513 int error;
1514 struct sockaddr_in *sin;
1515
1516 inp = sotoinpcb(so);
1517 KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1518 INP_INFO_WLOCK(&V_udbinfo);
1519 INP_WLOCK(inp);
1520 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1521 INP_WUNLOCK(inp);
1522 INP_INFO_WUNLOCK(&V_udbinfo);
1523 return (EISCONN);
1524 }
1525 sin = (struct sockaddr_in *)nam;
1526 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1527 if (error != 0) {
1528 INP_WUNLOCK(inp);
1529 INP_INFO_WUNLOCK(&V_udbinfo);
1530 return (error);
1531 }
1532 error = in_pcbconnect(inp, nam, td->td_ucred);
1533 if (error == 0)
1534 soisconnected(so);
1535 INP_WUNLOCK(inp);
1536 INP_INFO_WUNLOCK(&V_udbinfo);
1537 return (error);
1538 }
1539
1540 static void
1541 udp_detach(struct socket *so)
1542 {
1543 struct inpcb *inp;
1544 struct udpcb *up;
1545
1546 inp = sotoinpcb(so);
1547 KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1548 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1549 ("udp_detach: not disconnected"));
1550 INP_INFO_WLOCK(&V_udbinfo);
1551 INP_WLOCK(inp);
1552 up = intoudpcb(inp);
1553 KASSERT(up != NULL, ("%s: up == NULL", __func__));
1554 inp->inp_ppcb = NULL;
1555 in_pcbdetach(inp);
1556 in_pcbfree(inp);
1557 INP_INFO_WUNLOCK(&V_udbinfo);
1558 udp_discardcb(up);
1559 }
1560
1561 static int
1562 udp_disconnect(struct socket *so)
1563 {
1564 struct inpcb *inp;
1565
1566 inp = sotoinpcb(so);
1567 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1568 INP_INFO_WLOCK(&V_udbinfo);
1569 INP_WLOCK(inp);
1570 if (inp->inp_faddr.s_addr == INADDR_ANY) {
1571 INP_WUNLOCK(inp);
1572 INP_INFO_WUNLOCK(&V_udbinfo);
1573 return (ENOTCONN);
1574 }
1575
1576 in_pcbdisconnect(inp);
1577 inp->inp_laddr.s_addr = INADDR_ANY;
1578 SOCK_LOCK(so);
1579 so->so_state &= ~SS_ISCONNECTED; /* XXX */
1580 SOCK_UNLOCK(so);
1581 INP_WUNLOCK(inp);
1582 INP_INFO_WUNLOCK(&V_udbinfo);
1583 return (0);
1584 }
1585
1586 static int
1587 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1588 struct mbuf *control, struct thread *td)
1589 {
1590 struct inpcb *inp;
1591
1592 inp = sotoinpcb(so);
1593 KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1594 return (udp_output(inp, m, addr, control, td));
1595 }
1596
1597 int
1598 udp_shutdown(struct socket *so)
1599 {
1600 struct inpcb *inp;
1601
1602 inp = sotoinpcb(so);
1603 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1604 INP_WLOCK(inp);
1605 socantsendmore(so);
1606 INP_WUNLOCK(inp);
1607 return (0);
1608 }
1609
1610 struct pr_usrreqs udp_usrreqs = {
1611 .pru_abort = udp_abort,
1612 .pru_attach = udp_attach,
1613 .pru_bind = udp_bind,
1614 .pru_connect = udp_connect,
1615 .pru_control = in_control,
1616 .pru_detach = udp_detach,
1617 .pru_disconnect = udp_disconnect,
1618 .pru_peeraddr = in_getpeeraddr,
1619 .pru_send = udp_send,
1620 .pru_soreceive = soreceive_dgram,
1621 .pru_sosend = sosend_dgram,
1622 .pru_shutdown = udp_shutdown,
1623 .pru_sockaddr = in_getsockaddr,
1624 .pru_sosetlabel = in_pcbsosetlabel,
1625 .pru_close = udp_close,
1626 };
Cache object: dcd4ca58f8f4b837774723dde5a60f9f
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