1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
5 * The Regents of the University of California.
6 * Copyright (c) 2008 Robert N. M. Watson
7 * Copyright (c) 2010-2011 Juniper Networks, Inc.
8 * Copyright (c) 2014 Kevin Lo
9 * All rights reserved.
10 *
11 * Portions of this software were developed by Robert N. M. Watson under
12 * contract to Juniper Networks, Inc.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution.
22 * 3. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95
39 */
40
41 #include <sys/cdefs.h>
42 #include "opt_inet.h"
43 #include "opt_inet6.h"
44 #include "opt_ipsec.h"
45 #include "opt_route.h"
46 #include "opt_rss.h"
47
48 #include <sys/param.h>
49 #include <sys/domain.h>
50 #include <sys/eventhandler.h>
51 #include <sys/jail.h>
52 #include <sys/kernel.h>
53 #include <sys/lock.h>
54 #include <sys/malloc.h>
55 #include <sys/mbuf.h>
56 #include <sys/priv.h>
57 #include <sys/proc.h>
58 #include <sys/protosw.h>
59 #include <sys/sdt.h>
60 #include <sys/signalvar.h>
61 #include <sys/socket.h>
62 #include <sys/socketvar.h>
63 #include <sys/sx.h>
64 #include <sys/sysctl.h>
65 #include <sys/syslog.h>
66 #include <sys/systm.h>
67
68 #include <vm/uma.h>
69
70 #include <net/if.h>
71 #include <net/if_var.h>
72 #include <net/route.h>
73 #include <net/route/nhop.h>
74 #include <net/rss_config.h>
75
76 #include <netinet/in.h>
77 #include <netinet/in_kdtrace.h>
78 #include <netinet/in_fib.h>
79 #include <netinet/in_pcb.h>
80 #include <netinet/in_systm.h>
81 #include <netinet/in_var.h>
82 #include <netinet/ip.h>
83 #ifdef INET6
84 #include <netinet/ip6.h>
85 #endif
86 #include <netinet/ip_icmp.h>
87 #include <netinet/icmp_var.h>
88 #include <netinet/ip_var.h>
89 #include <netinet/ip_options.h>
90 #ifdef INET6
91 #include <netinet6/ip6_var.h>
92 #endif
93 #include <netinet/udp.h>
94 #include <netinet/udp_var.h>
95 #include <netinet/udplite.h>
96 #include <netinet/in_rss.h>
97
98 #include <netipsec/ipsec_support.h>
99
100 #include <machine/in_cksum.h>
101
102 #include <security/mac/mac_framework.h>
103
104 /*
105 * UDP and UDP-Lite protocols implementation.
106 * Per RFC 768, August, 1980.
107 * Per RFC 3828, July, 2004.
108 */
109
110 /*
111 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums
112 * removes the only data integrity mechanism for packets and malformed
113 * packets that would otherwise be discarded due to bad checksums, and may
114 * cause problems (especially for NFS data blocks).
115 */
116 VNET_DEFINE(int, udp_cksum) = 1;
117 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
118 &VNET_NAME(udp_cksum), 0, "compute udp checksum");
119
120 VNET_DEFINE(int, udp_log_in_vain) = 0;
121 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
122 &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets");
123
124 VNET_DEFINE(int, udp_blackhole) = 0;
125 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
126 &VNET_NAME(udp_blackhole), 0,
127 "Do not send port unreachables for refused connects");
128 VNET_DEFINE(bool, udp_blackhole_local) = false;
129 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET |
130 CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false,
131 "Enforce net.inet.udp.blackhole for locally originated packets");
132
133 u_long udp_sendspace = 9216; /* really max datagram size */
134 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
135 &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
136
137 u_long udp_recvspace = 40 * (1024 +
138 #ifdef INET6
139 sizeof(struct sockaddr_in6)
140 #else
141 sizeof(struct sockaddr_in)
142 #endif
143 ); /* 40 1K datagrams */
144
145 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
146 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
147
148 VNET_DEFINE(struct inpcbinfo, udbinfo);
149 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
150
151 #ifndef UDBHASHSIZE
152 #define UDBHASHSIZE 128
153 #endif
154
155 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat); /* from udp_var.h */
156 VNET_PCPUSTAT_SYSINIT(udpstat);
157 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
158 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
159
160 #ifdef VIMAGE
161 VNET_PCPUSTAT_SYSUNINIT(udpstat);
162 #endif /* VIMAGE */
163 #ifdef INET
164 static void udp_detach(struct socket *so);
165 #endif
166
167 INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash");
168 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb",
169 "udplite", "udplitehash");
170
171 static void
udp_vnet_init(void * arg __unused)172 udp_vnet_init(void *arg __unused)
173 {
174
175 /*
176 * For now default to 2-tuple UDP hashing - until the fragment
177 * reassembly code can also update the flowid.
178 *
179 * Once we can calculate the flowid that way and re-establish
180 * a 4-tuple, flip this to 4-tuple.
181 */
182 in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE);
183 /* Additional pcbinfo for UDP-Lite */
184 in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE,
185 UDBHASHSIZE);
186 }
187 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
188 udp_vnet_init, NULL);
189
190 /*
191 * Kernel module interface for updating udpstat. The argument is an index
192 * into udpstat treated as an array of u_long. While this encodes the
193 * general layout of udpstat into the caller, it doesn't encode its location,
194 * so that future changes to add, for example, per-CPU stats support won't
195 * cause binary compatibility problems for kernel modules.
196 */
197 void
kmod_udpstat_inc(int statnum)198 kmod_udpstat_inc(int statnum)
199 {
200
201 counter_u64_add(VNET(udpstat)[statnum], 1);
202 }
203
204 #ifdef VIMAGE
205 static void
udp_destroy(void * unused __unused)206 udp_destroy(void *unused __unused)
207 {
208
209 in_pcbinfo_destroy(&V_udbinfo);
210 in_pcbinfo_destroy(&V_ulitecbinfo);
211 }
212 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
213 #endif
214
215 #ifdef INET
216 /*
217 * Subroutine of udp_input(), which appends the provided mbuf chain to the
218 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that
219 * contains the source address. If the socket ends up being an IPv6 socket,
220 * udp_append() will convert to a sockaddr_in6 before passing the address
221 * into the socket code.
222 *
223 * In the normal case udp_append() will return 0, indicating that you
224 * must unlock the inp. However if a tunneling protocol is in place we increment
225 * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
226 * then decrement the reference count. If the inp_rele returns 1, indicating the
227 * inp is gone, we return that to the caller to tell them *not* to unlock
228 * the inp. In the case of multi-cast this will cause the distribution
229 * to stop (though most tunneling protocols known currently do *not* use
230 * multicast).
231 */
232 static int
udp_append(struct inpcb * inp,struct ip * ip,struct mbuf * n,int off,struct sockaddr_in * udp_in)233 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
234 struct sockaddr_in *udp_in)
235 {
236 struct sockaddr *append_sa;
237 struct socket *so;
238 struct mbuf *tmpopts, *opts = NULL;
239 #ifdef INET6
240 struct sockaddr_in6 udp_in6;
241 #endif
242 struct udpcb *up;
243 bool filtered;
244
245 INP_LOCK_ASSERT(inp);
246
247 /*
248 * Engage the tunneling protocol.
249 */
250 up = intoudpcb(inp);
251 if (up->u_tun_func != NULL) {
252 in_pcbref(inp);
253 INP_RUNLOCK(inp);
254 filtered = (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
255 up->u_tun_ctx);
256 INP_RLOCK(inp);
257 if (filtered)
258 return (in_pcbrele_rlocked(inp));
259 }
260
261 off += sizeof(struct udphdr);
262
263 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
264 /* Check AH/ESP integrity. */
265 if (IPSEC_ENABLED(ipv4) &&
266 IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
267 m_freem(n);
268 return (0);
269 }
270 if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
271 if (IPSEC_ENABLED(ipv4) &&
272 UDPENCAP_INPUT(n, off, AF_INET) != 0)
273 return (0); /* Consumed. */
274 }
275 #endif /* IPSEC */
276 #ifdef MAC
277 if (mac_inpcb_check_deliver(inp, n) != 0) {
278 m_freem(n);
279 return (0);
280 }
281 #endif /* MAC */
282 if (inp->inp_flags & INP_CONTROLOPTS ||
283 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
284 #ifdef INET6
285 if (inp->inp_vflag & INP_IPV6)
286 (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
287 else
288 #endif /* INET6 */
289 ip_savecontrol(inp, &opts, ip, n);
290 }
291 if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
292 tmpopts = sbcreatecontrol(&udp_in[1],
293 sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP,
294 M_NOWAIT);
295 if (tmpopts) {
296 if (opts) {
297 tmpopts->m_next = opts;
298 opts = tmpopts;
299 } else
300 opts = tmpopts;
301 }
302 }
303 #ifdef INET6
304 if (inp->inp_vflag & INP_IPV6) {
305 bzero(&udp_in6, sizeof(udp_in6));
306 udp_in6.sin6_len = sizeof(udp_in6);
307 udp_in6.sin6_family = AF_INET6;
308 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
309 append_sa = (struct sockaddr *)&udp_in6;
310 } else
311 #endif /* INET6 */
312 append_sa = (struct sockaddr *)&udp_in[0];
313 m_adj(n, off);
314
315 so = inp->inp_socket;
316 SOCKBUF_LOCK(&so->so_rcv);
317 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
318 soroverflow_locked(so);
319 m_freem(n);
320 if (opts)
321 m_freem(opts);
322 UDPSTAT_INC(udps_fullsock);
323 } else
324 sorwakeup_locked(so);
325 return (0);
326 }
327
328 static bool
udp_multi_match(const struct inpcb * inp,void * v)329 udp_multi_match(const struct inpcb *inp, void *v)
330 {
331 struct ip *ip = v;
332 struct udphdr *uh = (struct udphdr *)(ip + 1);
333
334 if (inp->inp_lport != uh->uh_dport)
335 return (false);
336 #ifdef INET6
337 if ((inp->inp_vflag & INP_IPV4) == 0)
338 return (false);
339 #endif
340 if (inp->inp_laddr.s_addr != INADDR_ANY &&
341 inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
342 return (false);
343 if (inp->inp_faddr.s_addr != INADDR_ANY &&
344 inp->inp_faddr.s_addr != ip->ip_src.s_addr)
345 return (false);
346 if (inp->inp_fport != 0 &&
347 inp->inp_fport != uh->uh_sport)
348 return (false);
349
350 return (true);
351 }
352
353 static int
udp_multi_input(struct mbuf * m,int proto,struct sockaddr_in * udp_in)354 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in)
355 {
356 struct ip *ip = mtod(m, struct ip *);
357 struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
358 INPLOOKUP_RLOCKPCB, udp_multi_match, ip);
359 #ifdef KDTRACE_HOOKS
360 struct udphdr *uh = (struct udphdr *)(ip + 1);
361 #endif
362 struct inpcb *inp;
363 struct mbuf *n;
364 int appends = 0;
365
366 MPASS(ip->ip_hl == sizeof(struct ip) >> 2);
367
368 while ((inp = inp_next(&inpi)) != NULL) {
369 /*
370 * XXXRW: Because we weren't holding either the inpcb
371 * or the hash lock when we checked for a match
372 * before, we should probably recheck now that the
373 * inpcb lock is held.
374 */
375 /*
376 * Handle socket delivery policy for any-source
377 * and source-specific multicast. [RFC3678]
378 */
379 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
380 struct ip_moptions *imo;
381 struct sockaddr_in group;
382 int blocked;
383
384 imo = inp->inp_moptions;
385 if (imo == NULL)
386 continue;
387 bzero(&group, sizeof(struct sockaddr_in));
388 group.sin_len = sizeof(struct sockaddr_in);
389 group.sin_family = AF_INET;
390 group.sin_addr = ip->ip_dst;
391
392 blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif,
393 (struct sockaddr *)&group,
394 (struct sockaddr *)&udp_in[0]);
395 if (blocked != MCAST_PASS) {
396 if (blocked == MCAST_NOTGMEMBER)
397 IPSTAT_INC(ips_notmember);
398 if (blocked == MCAST_NOTSMEMBER ||
399 blocked == MCAST_MUTED)
400 UDPSTAT_INC(udps_filtermcast);
401 continue;
402 }
403 }
404 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
405 if (proto == IPPROTO_UDPLITE)
406 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
407 else
408 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
409 if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) {
410 break;
411 } else
412 appends++;
413 }
414 /*
415 * Don't look for additional matches if this one does
416 * not have either the SO_REUSEPORT or SO_REUSEADDR
417 * socket options set. This heuristic avoids
418 * searching through all pcbs in the common case of a
419 * non-shared port. It assumes that an application
420 * will never clear these options after setting them.
421 */
422 if ((inp->inp_socket->so_options &
423 (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
424 INP_RUNLOCK(inp);
425 break;
426 }
427 }
428
429 if (appends == 0) {
430 /*
431 * No matching pcb found; discard datagram. (No need
432 * to send an ICMP Port Unreachable for a broadcast
433 * or multicast datgram.)
434 */
435 UDPSTAT_INC(udps_noport);
436 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
437 UDPSTAT_INC(udps_noportmcast);
438 else
439 UDPSTAT_INC(udps_noportbcast);
440 }
441 m_freem(m);
442
443 return (IPPROTO_DONE);
444 }
445
446 static int
udp_input(struct mbuf ** mp,int * offp,int proto)447 udp_input(struct mbuf **mp, int *offp, int proto)
448 {
449 struct ip *ip;
450 struct udphdr *uh;
451 struct ifnet *ifp;
452 struct inpcb *inp;
453 uint16_t len, ip_len;
454 struct inpcbinfo *pcbinfo;
455 struct sockaddr_in udp_in[2];
456 struct mbuf *m;
457 struct m_tag *fwd_tag;
458 int cscov_partial, iphlen;
459
460 m = *mp;
461 iphlen = *offp;
462 ifp = m->m_pkthdr.rcvif;
463 *mp = NULL;
464 UDPSTAT_INC(udps_ipackets);
465
466 /*
467 * Strip IP options, if any; should skip this, make available to
468 * user, and use on returned packets, but we don't yet have a way to
469 * check the checksum with options still present.
470 */
471 if (iphlen > sizeof (struct ip)) {
472 ip_stripoptions(m);
473 iphlen = sizeof(struct ip);
474 }
475
476 /*
477 * Get IP and UDP header together in first mbuf.
478 */
479 if (m->m_len < iphlen + sizeof(struct udphdr)) {
480 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
481 UDPSTAT_INC(udps_hdrops);
482 return (IPPROTO_DONE);
483 }
484 }
485 ip = mtod(m, struct ip *);
486 uh = (struct udphdr *)((caddr_t)ip + iphlen);
487 cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
488
489 /*
490 * Destination port of 0 is illegal, based on RFC768.
491 */
492 if (uh->uh_dport == 0)
493 goto badunlocked;
494
495 /*
496 * Construct sockaddr format source address. Stuff source address
497 * and datagram in user buffer.
498 */
499 bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
500 udp_in[0].sin_len = sizeof(struct sockaddr_in);
501 udp_in[0].sin_family = AF_INET;
502 udp_in[0].sin_port = uh->uh_sport;
503 udp_in[0].sin_addr = ip->ip_src;
504 udp_in[1].sin_len = sizeof(struct sockaddr_in);
505 udp_in[1].sin_family = AF_INET;
506 udp_in[1].sin_port = uh->uh_dport;
507 udp_in[1].sin_addr = ip->ip_dst;
508
509 /*
510 * Make mbuf data length reflect UDP length. If not enough data to
511 * reflect UDP length, drop.
512 */
513 len = ntohs((u_short)uh->uh_ulen);
514 ip_len = ntohs(ip->ip_len) - iphlen;
515 if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
516 /* Zero means checksum over the complete packet. */
517 if (len == 0)
518 len = ip_len;
519 cscov_partial = 0;
520 }
521 if (ip_len != len) {
522 if (len > ip_len || len < sizeof(struct udphdr)) {
523 UDPSTAT_INC(udps_badlen);
524 goto badunlocked;
525 }
526 if (proto == IPPROTO_UDP)
527 m_adj(m, len - ip_len);
528 }
529
530 /*
531 * Checksum extended UDP header and data.
532 */
533 if (uh->uh_sum) {
534 u_short uh_sum;
535
536 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
537 !cscov_partial) {
538 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
539 uh_sum = m->m_pkthdr.csum_data;
540 else
541 uh_sum = in_pseudo(ip->ip_src.s_addr,
542 ip->ip_dst.s_addr, htonl((u_short)len +
543 m->m_pkthdr.csum_data + proto));
544 uh_sum ^= 0xffff;
545 } else {
546 char b[offsetof(struct ipovly, ih_src)];
547 struct ipovly *ipov = (struct ipovly *)ip;
548
549 bcopy(ipov, b, sizeof(b));
550 bzero(ipov, sizeof(ipov->ih_x1));
551 ipov->ih_len = (proto == IPPROTO_UDP) ?
552 uh->uh_ulen : htons(ip_len);
553 uh_sum = in_cksum(m, len + sizeof (struct ip));
554 bcopy(b, ipov, sizeof(b));
555 }
556 if (uh_sum) {
557 UDPSTAT_INC(udps_badsum);
558 m_freem(m);
559 return (IPPROTO_DONE);
560 }
561 } else {
562 if (proto == IPPROTO_UDP) {
563 UDPSTAT_INC(udps_nosum);
564 } else {
565 /* UDPLite requires a checksum */
566 /* XXX: What is the right UDPLite MIB counter here? */
567 m_freem(m);
568 return (IPPROTO_DONE);
569 }
570 }
571
572 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
573 in_broadcast(ip->ip_dst, ifp))
574 return (udp_multi_input(m, proto, udp_in));
575
576 pcbinfo = udp_get_inpcbinfo(proto);
577
578 /*
579 * Locate pcb for datagram.
580 *
581 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
582 */
583 if ((m->m_flags & M_IP_NEXTHOP) &&
584 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
585 struct sockaddr_in *next_hop;
586
587 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
588
589 /*
590 * Transparently forwarded. Pretend to be the destination.
591 * Already got one like this?
592 */
593 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
594 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
595 if (!inp) {
596 /*
597 * It's new. Try to find the ambushing socket.
598 * Because we've rewritten the destination address,
599 * any hardware-generated hash is ignored.
600 */
601 inp = in_pcblookup(pcbinfo, ip->ip_src,
602 uh->uh_sport, next_hop->sin_addr,
603 next_hop->sin_port ? htons(next_hop->sin_port) :
604 uh->uh_dport, INPLOOKUP_WILDCARD |
605 INPLOOKUP_RLOCKPCB, ifp);
606 }
607 /* Remove the tag from the packet. We don't need it anymore. */
608 m_tag_delete(m, fwd_tag);
609 m->m_flags &= ~M_IP_NEXTHOP;
610 } else
611 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
612 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
613 INPLOOKUP_RLOCKPCB, ifp, m);
614 if (inp == NULL) {
615 if (V_udp_log_in_vain) {
616 char src[INET_ADDRSTRLEN];
617 char dst[INET_ADDRSTRLEN];
618
619 log(LOG_INFO,
620 "Connection attempt to UDP %s:%d from %s:%d\n",
621 inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
622 inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
623 }
624 if (proto == IPPROTO_UDPLITE)
625 UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
626 else
627 UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
628 UDPSTAT_INC(udps_noport);
629 if (m->m_flags & (M_BCAST | M_MCAST)) {
630 UDPSTAT_INC(udps_noportbcast);
631 goto badunlocked;
632 }
633 if (V_udp_blackhole && (V_udp_blackhole_local ||
634 !in_localip(ip->ip_src)))
635 goto badunlocked;
636 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
637 goto badunlocked;
638 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
639 return (IPPROTO_DONE);
640 }
641
642 /*
643 * Check the minimum TTL for socket.
644 */
645 INP_RLOCK_ASSERT(inp);
646 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
647 if (proto == IPPROTO_UDPLITE)
648 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
649 else
650 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
651 INP_RUNLOCK(inp);
652 m_freem(m);
653 return (IPPROTO_DONE);
654 }
655 if (cscov_partial) {
656 struct udpcb *up;
657
658 up = intoudpcb(inp);
659 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
660 INP_RUNLOCK(inp);
661 m_freem(m);
662 return (IPPROTO_DONE);
663 }
664 }
665
666 if (proto == IPPROTO_UDPLITE)
667 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
668 else
669 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
670 if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
671 INP_RUNLOCK(inp);
672 return (IPPROTO_DONE);
673
674 badunlocked:
675 m_freem(m);
676 return (IPPROTO_DONE);
677 }
678 #endif /* INET */
679
680 /*
681 * Notify a udp user of an asynchronous error; just wake up so that they can
682 * collect error status.
683 */
684 struct inpcb *
udp_notify(struct inpcb * inp,int errno)685 udp_notify(struct inpcb *inp, int errno)
686 {
687
688 INP_WLOCK_ASSERT(inp);
689 if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
690 errno == EHOSTDOWN) && inp->inp_route.ro_nh) {
691 NH_FREE(inp->inp_route.ro_nh);
692 inp->inp_route.ro_nh = (struct nhop_object *)NULL;
693 }
694
695 inp->inp_socket->so_error = errno;
696 sorwakeup(inp->inp_socket);
697 sowwakeup(inp->inp_socket);
698 return (inp);
699 }
700
701 #ifdef INET
702 static void
udp_common_ctlinput(struct icmp * icmp,struct inpcbinfo * pcbinfo)703 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo)
704 {
705 struct ip *ip = &icmp->icmp_ip;
706 struct udphdr *uh;
707 struct inpcb *inp;
708
709 if (icmp_errmap(icmp) == 0)
710 return;
711
712 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
713 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src,
714 uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
715 if (inp != NULL) {
716 INP_WLOCK_ASSERT(inp);
717 if (inp->inp_socket != NULL)
718 udp_notify(inp, icmp_errmap(icmp));
719 INP_WUNLOCK(inp);
720 } else {
721 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport,
722 ip->ip_src, uh->uh_sport,
723 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
724 if (inp != NULL) {
725 struct udpcb *up;
726 udp_tun_icmp_t *func;
727
728 up = intoudpcb(inp);
729 func = up->u_icmp_func;
730 INP_RUNLOCK(inp);
731 if (func != NULL)
732 func(icmp);
733 }
734 }
735 }
736
737 static void
udp_ctlinput(struct icmp * icmp)738 udp_ctlinput(struct icmp *icmp)
739 {
740
741 return (udp_common_ctlinput(icmp, &V_udbinfo));
742 }
743
744 static void
udplite_ctlinput(struct icmp * icmp)745 udplite_ctlinput(struct icmp *icmp)
746 {
747
748 return (udp_common_ctlinput(icmp, &V_ulitecbinfo));
749 }
750 #endif /* INET */
751
752 static int
udp_pcblist(SYSCTL_HANDLER_ARGS)753 udp_pcblist(SYSCTL_HANDLER_ARGS)
754 {
755 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_udbinfo,
756 INPLOOKUP_RLOCKPCB);
757 struct xinpgen xig;
758 struct inpcb *inp;
759 int error;
760
761 if (req->newptr != 0)
762 return (EPERM);
763
764 if (req->oldptr == 0) {
765 int n;
766
767 n = V_udbinfo.ipi_count;
768 n += imax(n / 8, 10);
769 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
770 return (0);
771 }
772
773 if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
774 return (error);
775
776 bzero(&xig, sizeof(xig));
777 xig.xig_len = sizeof xig;
778 xig.xig_count = V_udbinfo.ipi_count;
779 xig.xig_gen = V_udbinfo.ipi_gencnt;
780 xig.xig_sogen = so_gencnt;
781 error = SYSCTL_OUT(req, &xig, sizeof xig);
782 if (error)
783 return (error);
784
785 while ((inp = inp_next(&inpi)) != NULL) {
786 if (inp->inp_gencnt <= xig.xig_gen &&
787 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
788 struct xinpcb xi;
789
790 in_pcbtoxinpcb(inp, &xi);
791 error = SYSCTL_OUT(req, &xi, sizeof xi);
792 if (error) {
793 INP_RUNLOCK(inp);
794 break;
795 }
796 }
797 }
798
799 if (!error) {
800 /*
801 * Give the user an updated idea of our state. If the
802 * generation differs from what we told her before, she knows
803 * that something happened while we were processing this
804 * request, and it might be necessary to retry.
805 */
806 xig.xig_gen = V_udbinfo.ipi_gencnt;
807 xig.xig_sogen = so_gencnt;
808 xig.xig_count = V_udbinfo.ipi_count;
809 error = SYSCTL_OUT(req, &xig, sizeof xig);
810 }
811
812 return (error);
813 }
814
815 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
816 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
817 udp_pcblist, "S,xinpcb",
818 "List of active UDP sockets");
819
820 #ifdef INET
821 static int
udp_getcred(SYSCTL_HANDLER_ARGS)822 udp_getcred(SYSCTL_HANDLER_ARGS)
823 {
824 struct xucred xuc;
825 struct sockaddr_in addrs[2];
826 struct epoch_tracker et;
827 struct inpcb *inp;
828 int error;
829
830 error = priv_check(req->td, PRIV_NETINET_GETCRED);
831 if (error)
832 return (error);
833 error = SYSCTL_IN(req, addrs, sizeof(addrs));
834 if (error)
835 return (error);
836 NET_EPOCH_ENTER(et);
837 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
838 addrs[0].sin_addr, addrs[0].sin_port,
839 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
840 NET_EPOCH_EXIT(et);
841 if (inp != NULL) {
842 INP_RLOCK_ASSERT(inp);
843 if (inp->inp_socket == NULL)
844 error = ENOENT;
845 if (error == 0)
846 error = cr_canseeinpcb(req->td->td_ucred, inp);
847 if (error == 0)
848 cru2x(inp->inp_cred, &xuc);
849 INP_RUNLOCK(inp);
850 } else
851 error = ENOENT;
852 if (error == 0)
853 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
854 return (error);
855 }
856
857 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
858 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
859 0, 0, udp_getcred, "S,xucred",
860 "Get the xucred of a UDP connection");
861 #endif /* INET */
862
863 int
udp_ctloutput(struct socket * so,struct sockopt * sopt)864 udp_ctloutput(struct socket *so, struct sockopt *sopt)
865 {
866 struct inpcb *inp;
867 struct udpcb *up;
868 int isudplite, error, optval;
869
870 error = 0;
871 isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
872 inp = sotoinpcb(so);
873 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
874 INP_WLOCK(inp);
875 if (sopt->sopt_level != so->so_proto->pr_protocol) {
876 #ifdef INET6
877 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
878 INP_WUNLOCK(inp);
879 error = ip6_ctloutput(so, sopt);
880 }
881 #endif
882 #if defined(INET) && defined(INET6)
883 else
884 #endif
885 #ifdef INET
886 {
887 INP_WUNLOCK(inp);
888 error = ip_ctloutput(so, sopt);
889 }
890 #endif
891 return (error);
892 }
893
894 switch (sopt->sopt_dir) {
895 case SOPT_SET:
896 switch (sopt->sopt_name) {
897 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
898 #ifdef INET
899 case UDP_ENCAP:
900 if (!INP_CHECK_SOCKAF(so, AF_INET)) {
901 INP_WUNLOCK(inp);
902 return (EINVAL);
903 }
904 if (!IPSEC_ENABLED(ipv4)) {
905 INP_WUNLOCK(inp);
906 return (ENOPROTOOPT);
907 }
908 error = UDPENCAP_PCBCTL(inp, sopt);
909 break;
910 #endif /* INET */
911 #endif /* IPSEC */
912 case UDPLITE_SEND_CSCOV:
913 case UDPLITE_RECV_CSCOV:
914 if (!isudplite) {
915 INP_WUNLOCK(inp);
916 error = ENOPROTOOPT;
917 break;
918 }
919 INP_WUNLOCK(inp);
920 error = sooptcopyin(sopt, &optval, sizeof(optval),
921 sizeof(optval));
922 if (error != 0)
923 break;
924 inp = sotoinpcb(so);
925 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
926 INP_WLOCK(inp);
927 up = intoudpcb(inp);
928 KASSERT(up != NULL, ("%s: up == NULL", __func__));
929 if ((optval != 0 && optval < 8) || (optval > 65535)) {
930 INP_WUNLOCK(inp);
931 error = EINVAL;
932 break;
933 }
934 if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
935 up->u_txcslen = optval;
936 else
937 up->u_rxcslen = optval;
938 INP_WUNLOCK(inp);
939 break;
940 default:
941 INP_WUNLOCK(inp);
942 error = ENOPROTOOPT;
943 break;
944 }
945 break;
946 case SOPT_GET:
947 switch (sopt->sopt_name) {
948 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
949 #ifdef INET
950 case UDP_ENCAP:
951 if (!INP_CHECK_SOCKAF(so, AF_INET)) {
952 INP_WUNLOCK(inp);
953 return (EINVAL);
954 }
955 if (!IPSEC_ENABLED(ipv4)) {
956 INP_WUNLOCK(inp);
957 return (ENOPROTOOPT);
958 }
959 error = UDPENCAP_PCBCTL(inp, sopt);
960 break;
961 #endif /* INET */
962 #endif /* IPSEC */
963 case UDPLITE_SEND_CSCOV:
964 case UDPLITE_RECV_CSCOV:
965 if (!isudplite) {
966 INP_WUNLOCK(inp);
967 error = ENOPROTOOPT;
968 break;
969 }
970 up = intoudpcb(inp);
971 KASSERT(up != NULL, ("%s: up == NULL", __func__));
972 if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
973 optval = up->u_txcslen;
974 else
975 optval = up->u_rxcslen;
976 INP_WUNLOCK(inp);
977 error = sooptcopyout(sopt, &optval, sizeof(optval));
978 break;
979 default:
980 INP_WUNLOCK(inp);
981 error = ENOPROTOOPT;
982 break;
983 }
984 break;
985 }
986 return (error);
987 }
988
989 #ifdef INET
990 #ifdef INET6
991 /* The logic here is derived from ip6_setpktopt(). See comments there. */
992 static int
udp_v4mapped_pktinfo(struct cmsghdr * cm,struct sockaddr_in * src,struct inpcb * inp,int flags)993 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src,
994 struct inpcb *inp, int flags)
995 {
996 struct ifnet *ifp;
997 struct in6_pktinfo *pktinfo;
998 struct in_addr ia;
999
1000 if ((flags & PRUS_IPV6) == 0)
1001 return (0);
1002
1003 if (cm->cmsg_level != IPPROTO_IPV6)
1004 return (0);
1005
1006 if (cm->cmsg_type != IPV6_2292PKTINFO &&
1007 cm->cmsg_type != IPV6_PKTINFO)
1008 return (0);
1009
1010 if (cm->cmsg_len !=
1011 CMSG_LEN(sizeof(struct in6_pktinfo)))
1012 return (EINVAL);
1013
1014 pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm);
1015 if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) &&
1016 !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr))
1017 return (EINVAL);
1018
1019 /* Validate the interface index if specified. */
1020 if (pktinfo->ipi6_ifindex) {
1021 struct epoch_tracker et;
1022
1023 NET_EPOCH_ENTER(et);
1024 ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
1025 NET_EPOCH_EXIT(et); /* XXXGL: unsafe ifp */
1026 if (ifp == NULL)
1027 return (ENXIO);
1028 } else
1029 ifp = NULL;
1030 if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
1031 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1032 if (in_ifhasaddr(ifp, ia) == 0)
1033 return (EADDRNOTAVAIL);
1034 }
1035
1036 bzero(src, sizeof(*src));
1037 src->sin_family = AF_INET;
1038 src->sin_len = sizeof(*src);
1039 src->sin_port = inp->inp_lport;
1040 src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1041
1042 return (0);
1043 }
1044 #endif /* INET6 */
1045
1046 int
udp_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct thread * td)1047 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1048 struct mbuf *control, struct thread *td)
1049 {
1050 struct inpcb *inp;
1051 struct udpiphdr *ui;
1052 int len, error = 0;
1053 struct in_addr faddr, laddr;
1054 struct cmsghdr *cm;
1055 struct inpcbinfo *pcbinfo;
1056 struct sockaddr_in *sin, src;
1057 struct epoch_tracker et;
1058 int cscov_partial = 0;
1059 int ipflags = 0;
1060 u_short fport, lport;
1061 u_char tos, vflagsav;
1062 uint8_t pr;
1063 uint16_t cscov = 0;
1064 uint32_t flowid = 0;
1065 uint8_t flowtype = M_HASHTYPE_NONE;
1066 bool use_cached_route;
1067
1068 inp = sotoinpcb(so);
1069 KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1070
1071 if (addr != NULL) {
1072 if (addr->sa_family != AF_INET)
1073 error = EAFNOSUPPORT;
1074 else if (addr->sa_len != sizeof(struct sockaddr_in))
1075 error = EINVAL;
1076 if (__predict_false(error != 0)) {
1077 m_freem(control);
1078 m_freem(m);
1079 return (error);
1080 }
1081 }
1082
1083 len = m->m_pkthdr.len;
1084 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1085 if (control)
1086 m_freem(control);
1087 m_freem(m);
1088 return (EMSGSIZE);
1089 }
1090
1091 src.sin_family = 0;
1092 sin = (struct sockaddr_in *)addr;
1093
1094 /*
1095 * udp_send() may need to temporarily bind or connect the current
1096 * inpcb. As such, we don't know up front whether we will need the
1097 * pcbinfo lock or not. Do any work to decide what is needed up
1098 * front before acquiring any locks.
1099 *
1100 * We will need network epoch in either case, to safely lookup into
1101 * pcb hash.
1102 */
1103 use_cached_route = sin == NULL || (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0);
1104 if (use_cached_route || (flags & PRUS_IPV6) != 0)
1105 INP_WLOCK(inp);
1106 else
1107 INP_RLOCK(inp);
1108 NET_EPOCH_ENTER(et);
1109 tos = inp->inp_ip_tos;
1110 if (control != NULL) {
1111 /*
1112 * XXX: Currently, we assume all the optional information is
1113 * stored in a single mbuf.
1114 */
1115 if (control->m_next) {
1116 m_freem(control);
1117 error = EINVAL;
1118 goto release;
1119 }
1120 for (; control->m_len > 0;
1121 control->m_data += CMSG_ALIGN(cm->cmsg_len),
1122 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1123 cm = mtod(control, struct cmsghdr *);
1124 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1125 || cm->cmsg_len > control->m_len) {
1126 error = EINVAL;
1127 break;
1128 }
1129 #ifdef INET6
1130 error = udp_v4mapped_pktinfo(cm, &src, inp, flags);
1131 if (error != 0)
1132 break;
1133 #endif
1134 if (cm->cmsg_level != IPPROTO_IP)
1135 continue;
1136
1137 switch (cm->cmsg_type) {
1138 case IP_SENDSRCADDR:
1139 if (cm->cmsg_len !=
1140 CMSG_LEN(sizeof(struct in_addr))) {
1141 error = EINVAL;
1142 break;
1143 }
1144 bzero(&src, sizeof(src));
1145 src.sin_family = AF_INET;
1146 src.sin_len = sizeof(src);
1147 src.sin_port = inp->inp_lport;
1148 src.sin_addr =
1149 *(struct in_addr *)CMSG_DATA(cm);
1150 break;
1151
1152 case IP_TOS:
1153 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1154 error = EINVAL;
1155 break;
1156 }
1157 tos = *(u_char *)CMSG_DATA(cm);
1158 break;
1159
1160 case IP_FLOWID:
1161 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1162 error = EINVAL;
1163 break;
1164 }
1165 flowid = *(uint32_t *) CMSG_DATA(cm);
1166 break;
1167
1168 case IP_FLOWTYPE:
1169 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1170 error = EINVAL;
1171 break;
1172 }
1173 flowtype = *(uint32_t *) CMSG_DATA(cm);
1174 break;
1175
1176 #ifdef RSS
1177 case IP_RSSBUCKETID:
1178 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1179 error = EINVAL;
1180 break;
1181 }
1182 /* This is just a placeholder for now */
1183 break;
1184 #endif /* RSS */
1185 default:
1186 error = ENOPROTOOPT;
1187 break;
1188 }
1189 if (error)
1190 break;
1191 }
1192 m_freem(control);
1193 control = NULL;
1194 }
1195 if (error)
1196 goto release;
1197
1198 pr = inp->inp_socket->so_proto->pr_protocol;
1199 pcbinfo = udp_get_inpcbinfo(pr);
1200
1201 /*
1202 * If the IP_SENDSRCADDR control message was specified, override the
1203 * source address for this datagram. Its use is invalidated if the
1204 * address thus specified is incomplete or clobbers other inpcbs.
1205 */
1206 laddr = inp->inp_laddr;
1207 lport = inp->inp_lport;
1208 if (src.sin_family == AF_INET) {
1209 if ((lport == 0) ||
1210 (laddr.s_addr == INADDR_ANY &&
1211 src.sin_addr.s_addr == INADDR_ANY)) {
1212 error = EINVAL;
1213 goto release;
1214 }
1215 if ((flags & PRUS_IPV6) != 0) {
1216 vflagsav = inp->inp_vflag;
1217 inp->inp_vflag |= INP_IPV4;
1218 inp->inp_vflag &= ~INP_IPV6;
1219 }
1220 INP_HASH_WLOCK(pcbinfo);
1221 error = in_pcbbind_setup(inp, &src, &laddr.s_addr, &lport,
1222 td->td_ucred);
1223 INP_HASH_WUNLOCK(pcbinfo);
1224 if ((flags & PRUS_IPV6) != 0)
1225 inp->inp_vflag = vflagsav;
1226 if (error)
1227 goto release;
1228 }
1229
1230 /*
1231 * If a UDP socket has been connected, then a local address/port will
1232 * have been selected and bound.
1233 *
1234 * If a UDP socket has not been connected to, then an explicit
1235 * destination address must be used, in which case a local
1236 * address/port may not have been selected and bound.
1237 */
1238 if (sin != NULL) {
1239 INP_LOCK_ASSERT(inp);
1240 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1241 error = EISCONN;
1242 goto release;
1243 }
1244
1245 /*
1246 * Jail may rewrite the destination address, so let it do
1247 * that before we use it.
1248 */
1249 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1250 if (error)
1251 goto release;
1252
1253 /*
1254 * If a local address or port hasn't yet been selected, or if
1255 * the destination address needs to be rewritten due to using
1256 * a special INADDR_ constant, invoke in_pcbconnect_setup()
1257 * to do the heavy lifting. Once a port is selected, we
1258 * commit the binding back to the socket; we also commit the
1259 * binding of the address if in jail.
1260 *
1261 * If we already have a valid binding and we're not
1262 * requesting a destination address rewrite, use a fast path.
1263 */
1264 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1265 inp->inp_lport == 0 ||
1266 sin->sin_addr.s_addr == INADDR_ANY ||
1267 sin->sin_addr.s_addr == INADDR_BROADCAST) {
1268 if ((flags & PRUS_IPV6) != 0) {
1269 vflagsav = inp->inp_vflag;
1270 inp->inp_vflag |= INP_IPV4;
1271 inp->inp_vflag &= ~INP_IPV6;
1272 }
1273 INP_HASH_WLOCK(pcbinfo);
1274 error = in_pcbconnect_setup(inp, sin, &laddr.s_addr,
1275 &lport, &faddr.s_addr, &fport, td->td_ucred);
1276 if ((flags & PRUS_IPV6) != 0)
1277 inp->inp_vflag = vflagsav;
1278 if (error) {
1279 INP_HASH_WUNLOCK(pcbinfo);
1280 goto release;
1281 }
1282
1283 /*
1284 * XXXRW: Why not commit the port if the address is
1285 * !INADDR_ANY?
1286 */
1287 /* Commit the local port if newly assigned. */
1288 if (inp->inp_laddr.s_addr == INADDR_ANY &&
1289 inp->inp_lport == 0) {
1290 INP_WLOCK_ASSERT(inp);
1291 /*
1292 * Remember addr if jailed, to prevent
1293 * rebinding.
1294 */
1295 if (prison_flag(td->td_ucred, PR_IP4))
1296 inp->inp_laddr = laddr;
1297 inp->inp_lport = lport;
1298 error = in_pcbinshash(inp);
1299 INP_HASH_WUNLOCK(pcbinfo);
1300 if (error != 0) {
1301 inp->inp_lport = 0;
1302 error = EAGAIN;
1303 goto release;
1304 }
1305 inp->inp_flags |= INP_ANONPORT;
1306 } else
1307 INP_HASH_WUNLOCK(pcbinfo);
1308 } else {
1309 faddr = sin->sin_addr;
1310 fport = sin->sin_port;
1311 }
1312 } else {
1313 INP_LOCK_ASSERT(inp);
1314 faddr = inp->inp_faddr;
1315 fport = inp->inp_fport;
1316 if (faddr.s_addr == INADDR_ANY) {
1317 error = ENOTCONN;
1318 goto release;
1319 }
1320 }
1321
1322 /*
1323 * Calculate data length and get a mbuf for UDP, IP, and possible
1324 * link-layer headers. Immediate slide the data pointer back forward
1325 * since we won't use that space at this layer.
1326 */
1327 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1328 if (m == NULL) {
1329 error = ENOBUFS;
1330 goto release;
1331 }
1332 m->m_data += max_linkhdr;
1333 m->m_len -= max_linkhdr;
1334 m->m_pkthdr.len -= max_linkhdr;
1335
1336 /*
1337 * Fill in mbuf with extended UDP header and addresses and length put
1338 * into network format.
1339 */
1340 ui = mtod(m, struct udpiphdr *);
1341 /*
1342 * Filling only those fields of udpiphdr that participate in the
1343 * checksum calculation. The rest must be zeroed and will be filled
1344 * later.
1345 */
1346 bzero(ui->ui_x1, sizeof(ui->ui_x1));
1347 ui->ui_pr = pr;
1348 ui->ui_src = laddr;
1349 ui->ui_dst = faddr;
1350 ui->ui_sport = lport;
1351 ui->ui_dport = fport;
1352 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1353 if (pr == IPPROTO_UDPLITE) {
1354 struct udpcb *up;
1355 uint16_t plen;
1356
1357 up = intoudpcb(inp);
1358 cscov = up->u_txcslen;
1359 plen = (u_short)len + sizeof(struct udphdr);
1360 if (cscov >= plen)
1361 cscov = 0;
1362 ui->ui_len = htons(plen);
1363 ui->ui_ulen = htons(cscov);
1364 /*
1365 * For UDP-Lite, checksum coverage length of zero means
1366 * the entire UDPLite packet is covered by the checksum.
1367 */
1368 cscov_partial = (cscov == 0) ? 0 : 1;
1369 }
1370
1371 if (inp->inp_socket->so_options & SO_DONTROUTE)
1372 ipflags |= IP_ROUTETOIF;
1373 if (inp->inp_socket->so_options & SO_BROADCAST)
1374 ipflags |= IP_ALLOWBROADCAST;
1375 if (inp->inp_flags & INP_ONESBCAST)
1376 ipflags |= IP_SENDONES;
1377
1378 #ifdef MAC
1379 mac_inpcb_create_mbuf(inp, m);
1380 #endif
1381
1382 /*
1383 * Set up checksum and output datagram.
1384 */
1385 ui->ui_sum = 0;
1386 if (pr == IPPROTO_UDPLITE) {
1387 if (inp->inp_flags & INP_ONESBCAST)
1388 faddr.s_addr = INADDR_BROADCAST;
1389 if (cscov_partial) {
1390 if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1391 ui->ui_sum = 0xffff;
1392 } else {
1393 if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1394 ui->ui_sum = 0xffff;
1395 }
1396 } else if (V_udp_cksum) {
1397 if (inp->inp_flags & INP_ONESBCAST)
1398 faddr.s_addr = INADDR_BROADCAST;
1399 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1400 htons((u_short)len + sizeof(struct udphdr) + pr));
1401 m->m_pkthdr.csum_flags = CSUM_UDP;
1402 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1403 }
1404 /*
1405 * After finishing the checksum computation, fill the remaining fields
1406 * of udpiphdr.
1407 */
1408 ((struct ip *)ui)->ip_v = IPVERSION;
1409 ((struct ip *)ui)->ip_tos = tos;
1410 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1411 if (inp->inp_flags & INP_DONTFRAG)
1412 ((struct ip *)ui)->ip_off |= htons(IP_DF);
1413 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;
1414 UDPSTAT_INC(udps_opackets);
1415
1416 /*
1417 * Setup flowid / RSS information for outbound socket.
1418 *
1419 * Once the UDP code decides to set a flowid some other way,
1420 * this allows the flowid to be overridden by userland.
1421 */
1422 if (flowtype != M_HASHTYPE_NONE) {
1423 m->m_pkthdr.flowid = flowid;
1424 M_HASHTYPE_SET(m, flowtype);
1425 }
1426 #if defined(ROUTE_MPATH) || defined(RSS)
1427 else if (CALC_FLOWID_OUTBOUND_SENDTO) {
1428 uint32_t hash_val, hash_type;
1429
1430 hash_val = fib4_calc_packet_hash(laddr, faddr,
1431 lport, fport, pr, &hash_type);
1432 m->m_pkthdr.flowid = hash_val;
1433 M_HASHTYPE_SET(m, hash_type);
1434 }
1435
1436 /*
1437 * Don't override with the inp cached flowid value.
1438 *
1439 * Depending upon the kind of send being done, the inp
1440 * flowid/flowtype values may actually not be appropriate
1441 * for this particular socket send.
1442 *
1443 * We should either leave the flowid at zero (which is what is
1444 * currently done) or set it to some software generated
1445 * hash value based on the packet contents.
1446 */
1447 ipflags |= IP_NODEFAULTFLOWID;
1448 #endif /* RSS */
1449
1450 if (pr == IPPROTO_UDPLITE)
1451 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1452 else
1453 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1454 error = ip_output(m, inp->inp_options,
1455 use_cached_route ? &inp->inp_route : NULL, ipflags,
1456 inp->inp_moptions, inp);
1457 INP_UNLOCK(inp);
1458 NET_EPOCH_EXIT(et);
1459 return (error);
1460
1461 release:
1462 INP_UNLOCK(inp);
1463 NET_EPOCH_EXIT(et);
1464 m_freem(m);
1465 return (error);
1466 }
1467
1468 void
udp_abort(struct socket * so)1469 udp_abort(struct socket *so)
1470 {
1471 struct inpcb *inp;
1472 struct inpcbinfo *pcbinfo;
1473
1474 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1475 inp = sotoinpcb(so);
1476 KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1477 INP_WLOCK(inp);
1478 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1479 INP_HASH_WLOCK(pcbinfo);
1480 in_pcbdisconnect(inp);
1481 INP_HASH_WUNLOCK(pcbinfo);
1482 soisdisconnected(so);
1483 }
1484 INP_WUNLOCK(inp);
1485 }
1486
1487 static int
udp_attach(struct socket * so,int proto,struct thread * td)1488 udp_attach(struct socket *so, int proto, struct thread *td)
1489 {
1490 static uint32_t udp_flowid;
1491 struct inpcbinfo *pcbinfo;
1492 struct inpcb *inp;
1493 struct udpcb *up;
1494 int error;
1495
1496 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1497 inp = sotoinpcb(so);
1498 KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1499 error = soreserve(so, udp_sendspace, udp_recvspace);
1500 if (error)
1501 return (error);
1502 error = in_pcballoc(so, pcbinfo);
1503 if (error)
1504 return (error);
1505
1506 inp = sotoinpcb(so);
1507 inp->inp_ip_ttl = V_ip_defttl;
1508 inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1509 inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1510 up = intoudpcb(inp);
1511 bzero(&up->u_start_zero, u_zero_size);
1512 INP_WUNLOCK(inp);
1513
1514 return (0);
1515 }
1516 #endif /* INET */
1517
1518 int
udp_set_kernel_tunneling(struct socket * so,udp_tun_func_t f,udp_tun_icmp_t i,void * ctx)1519 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1520 {
1521 struct inpcb *inp;
1522 struct udpcb *up;
1523
1524 KASSERT(so->so_type == SOCK_DGRAM,
1525 ("udp_set_kernel_tunneling: !dgram"));
1526 inp = sotoinpcb(so);
1527 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1528 INP_WLOCK(inp);
1529 up = intoudpcb(inp);
1530 if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) ||
1531 (up->u_icmp_func != NULL))) {
1532 INP_WUNLOCK(inp);
1533 return (EBUSY);
1534 }
1535 up->u_tun_func = f;
1536 up->u_icmp_func = i;
1537 up->u_tun_ctx = ctx;
1538 INP_WUNLOCK(inp);
1539 return (0);
1540 }
1541
1542 #ifdef INET
1543 static int
udp_bind(struct socket * so,struct sockaddr * nam,struct thread * td)1544 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1545 {
1546 struct inpcb *inp;
1547 struct inpcbinfo *pcbinfo;
1548 struct sockaddr_in *sinp;
1549 int error;
1550
1551 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1552 inp = sotoinpcb(so);
1553 KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1554
1555 sinp = (struct sockaddr_in *)nam;
1556 if (nam->sa_family != AF_INET) {
1557 /*
1558 * Preserve compatibility with old programs.
1559 */
1560 if (nam->sa_family != AF_UNSPEC ||
1561 nam->sa_len < offsetof(struct sockaddr_in, sin_zero) ||
1562 sinp->sin_addr.s_addr != INADDR_ANY)
1563 return (EAFNOSUPPORT);
1564 nam->sa_family = AF_INET;
1565 }
1566 if (nam->sa_len != sizeof(struct sockaddr_in))
1567 return (EINVAL);
1568
1569 INP_WLOCK(inp);
1570 INP_HASH_WLOCK(pcbinfo);
1571 error = in_pcbbind(inp, sinp, td->td_ucred);
1572 INP_HASH_WUNLOCK(pcbinfo);
1573 INP_WUNLOCK(inp);
1574 return (error);
1575 }
1576
1577 static void
udp_close(struct socket * so)1578 udp_close(struct socket *so)
1579 {
1580 struct inpcb *inp;
1581 struct inpcbinfo *pcbinfo;
1582
1583 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1584 inp = sotoinpcb(so);
1585 KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1586 INP_WLOCK(inp);
1587 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1588 INP_HASH_WLOCK(pcbinfo);
1589 in_pcbdisconnect(inp);
1590 INP_HASH_WUNLOCK(pcbinfo);
1591 soisdisconnected(so);
1592 }
1593 INP_WUNLOCK(inp);
1594 }
1595
1596 static int
udp_connect(struct socket * so,struct sockaddr * nam,struct thread * td)1597 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1598 {
1599 struct epoch_tracker et;
1600 struct inpcb *inp;
1601 struct inpcbinfo *pcbinfo;
1602 struct sockaddr_in *sin;
1603 int error;
1604
1605 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1606 inp = sotoinpcb(so);
1607 KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1608
1609 sin = (struct sockaddr_in *)nam;
1610 if (sin->sin_family != AF_INET)
1611 return (EAFNOSUPPORT);
1612 if (sin->sin_len != sizeof(*sin))
1613 return (EINVAL);
1614
1615 INP_WLOCK(inp);
1616 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1617 INP_WUNLOCK(inp);
1618 return (EISCONN);
1619 }
1620 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1621 if (error != 0) {
1622 INP_WUNLOCK(inp);
1623 return (error);
1624 }
1625 NET_EPOCH_ENTER(et);
1626 INP_HASH_WLOCK(pcbinfo);
1627 error = in_pcbconnect(inp, sin, td->td_ucred, true);
1628 INP_HASH_WUNLOCK(pcbinfo);
1629 NET_EPOCH_EXIT(et);
1630 if (error == 0)
1631 soisconnected(so);
1632 INP_WUNLOCK(inp);
1633 return (error);
1634 }
1635
1636 static void
udp_detach(struct socket * so)1637 udp_detach(struct socket *so)
1638 {
1639 struct inpcb *inp;
1640
1641 inp = sotoinpcb(so);
1642 KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1643 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1644 ("udp_detach: not disconnected"));
1645 INP_WLOCK(inp);
1646 in_pcbfree(inp);
1647 }
1648
1649 int
udp_disconnect(struct socket * so)1650 udp_disconnect(struct socket *so)
1651 {
1652 struct inpcb *inp;
1653 struct inpcbinfo *pcbinfo;
1654
1655 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1656 inp = sotoinpcb(so);
1657 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1658 INP_WLOCK(inp);
1659 if (inp->inp_faddr.s_addr == INADDR_ANY) {
1660 INP_WUNLOCK(inp);
1661 return (ENOTCONN);
1662 }
1663 INP_HASH_WLOCK(pcbinfo);
1664 in_pcbdisconnect(inp);
1665 INP_HASH_WUNLOCK(pcbinfo);
1666 SOCK_LOCK(so);
1667 so->so_state &= ~SS_ISCONNECTED; /* XXX */
1668 SOCK_UNLOCK(so);
1669 INP_WUNLOCK(inp);
1670 return (0);
1671 }
1672 #endif /* INET */
1673
1674 int
udp_shutdown(struct socket * so)1675 udp_shutdown(struct socket *so)
1676 {
1677 struct inpcb *inp;
1678
1679 inp = sotoinpcb(so);
1680 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1681 INP_WLOCK(inp);
1682 socantsendmore(so);
1683 INP_WUNLOCK(inp);
1684 return (0);
1685 }
1686
1687 #ifdef INET
1688 #define UDP_PROTOSW \
1689 .pr_type = SOCK_DGRAM, \
1690 .pr_flags = PR_ATOMIC | PR_ADDR | PR_CAPATTACH, \
1691 .pr_ctloutput = udp_ctloutput, \
1692 .pr_abort = udp_abort, \
1693 .pr_attach = udp_attach, \
1694 .pr_bind = udp_bind, \
1695 .pr_connect = udp_connect, \
1696 .pr_control = in_control, \
1697 .pr_detach = udp_detach, \
1698 .pr_disconnect = udp_disconnect, \
1699 .pr_peeraddr = in_getpeeraddr, \
1700 .pr_send = udp_send, \
1701 .pr_soreceive = soreceive_dgram, \
1702 .pr_sosend = sosend_dgram, \
1703 .pr_shutdown = udp_shutdown, \
1704 .pr_sockaddr = in_getsockaddr, \
1705 .pr_sosetlabel = in_pcbsosetlabel, \
1706 .pr_close = udp_close
1707
1708 struct protosw udp_protosw = {
1709 .pr_protocol = IPPROTO_UDP,
1710 UDP_PROTOSW
1711 };
1712
1713 struct protosw udplite_protosw = {
1714 .pr_protocol = IPPROTO_UDPLITE,
1715 UDP_PROTOSW
1716 };
1717
1718 static void
udp_init(void * arg __unused)1719 udp_init(void *arg __unused)
1720 {
1721
1722 IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput);
1723 IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput);
1724 }
1725 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL);
1726 #endif /* INET */
1727