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
39 #include <sys/cdefs.h>
40 #include "opt_inet.h"
41 #include "opt_inet6.h"
42 #include "opt_ipsec.h"
43 #include "opt_route.h"
44 #include "opt_rss.h"
45
46 #include <sys/param.h>
47 #include <sys/domain.h>
48 #include <sys/eventhandler.h>
49 #include <sys/jail.h>
50 #include <sys/kernel.h>
51 #include <sys/lock.h>
52 #include <sys/malloc.h>
53 #include <sys/mbuf.h>
54 #include <sys/priv.h>
55 #include <sys/proc.h>
56 #include <sys/protosw.h>
57 #include <sys/sdt.h>
58 #include <sys/signalvar.h>
59 #include <sys/socket.h>
60 #include <sys/socketvar.h>
61 #include <sys/sx.h>
62 #include <sys/sysctl.h>
63 #include <sys/syslog.h>
64 #include <sys/systm.h>
65
66 #include <vm/uma.h>
67
68 #include <net/if.h>
69 #include <net/if_var.h>
70 #include <net/route.h>
71 #include <net/route/nhop.h>
72 #include <net/rss_config.h>
73
74 #include <netinet/in.h>
75 #include <netinet/in_kdtrace.h>
76 #include <netinet/in_fib.h>
77 #include <netinet/in_pcb.h>
78 #include <netinet/in_systm.h>
79 #include <netinet/in_var.h>
80 #include <netinet/ip.h>
81 #ifdef INET6
82 #include <netinet/ip6.h>
83 #endif
84 #include <netinet/ip_icmp.h>
85 #include <netinet/icmp_var.h>
86 #include <netinet/ip_var.h>
87 #include <netinet/ip_options.h>
88 #ifdef INET6
89 #include <netinet6/ip6_var.h>
90 #endif
91 #include <netinet/udp.h>
92 #include <netinet/udp_var.h>
93 #include <netinet/udplite.h>
94 #include <netinet/in_rss.h>
95
96 #include <netipsec/ipsec_support.h>
97
98 #include <machine/in_cksum.h>
99
100 #include <security/mac/mac_framework.h>
101
102 /*
103 * UDP and UDP-Lite protocols implementation.
104 * Per RFC 768, August, 1980.
105 * Per RFC 3828, July, 2004.
106 */
107
108 /*
109 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums
110 * removes the only data integrity mechanism for packets and malformed
111 * packets that would otherwise be discarded due to bad checksums, and may
112 * cause problems (especially for NFS data blocks).
113 */
114 VNET_DEFINE(int, udp_cksum) = 1;
115 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
116 &VNET_NAME(udp_cksum), 0, "compute udp checksum");
117
118 VNET_DEFINE(int, udp_log_in_vain) = 0;
119 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
120 &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets");
121
122 VNET_DEFINE(int, udp_blackhole) = 0;
123 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
124 &VNET_NAME(udp_blackhole), 0,
125 "Do not send port unreachables for refused connects");
126 VNET_DEFINE(bool, udp_blackhole_local) = false;
127 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET |
128 CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false,
129 "Enforce net.inet.udp.blackhole for locally originated packets");
130
131 u_long udp_sendspace = 9216; /* really max datagram size */
132 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
133 &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
134
135 u_long udp_recvspace = 40 * (1024 +
136 #ifdef INET6
137 sizeof(struct sockaddr_in6)
138 #else
139 sizeof(struct sockaddr_in)
140 #endif
141 ); /* 40 1K datagrams */
142
143 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
144 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
145
146 VNET_DEFINE(struct inpcbinfo, udbinfo);
147 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
148
149 #ifndef UDBHASHSIZE
150 #define UDBHASHSIZE 128
151 #endif
152
153 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat); /* from udp_var.h */
154 VNET_PCPUSTAT_SYSINIT(udpstat);
155 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
156 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
157
158 #ifdef VIMAGE
159 VNET_PCPUSTAT_SYSUNINIT(udpstat);
160 #endif /* VIMAGE */
161 #ifdef INET
162 static void udp_detach(struct socket *so);
163 #endif
164
165 INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash");
166 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb",
167 "udplite", "udplitehash");
168
169 static void
udp_vnet_init(void * arg __unused)170 udp_vnet_init(void *arg __unused)
171 {
172
173 /*
174 * For now default to 2-tuple UDP hashing - until the fragment
175 * reassembly code can also update the flowid.
176 *
177 * Once we can calculate the flowid that way and re-establish
178 * a 4-tuple, flip this to 4-tuple.
179 */
180 in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE);
181 /* Additional pcbinfo for UDP-Lite */
182 in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE,
183 UDBHASHSIZE);
184 }
185 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
186 udp_vnet_init, NULL);
187
188 /*
189 * Kernel module interface for updating udpstat. The argument is an index
190 * into udpstat treated as an array of u_long. While this encodes the
191 * general layout of udpstat into the caller, it doesn't encode its location,
192 * so that future changes to add, for example, per-CPU stats support won't
193 * cause binary compatibility problems for kernel modules.
194 */
195 void
kmod_udpstat_inc(int statnum)196 kmod_udpstat_inc(int statnum)
197 {
198
199 counter_u64_add(VNET(udpstat)[statnum], 1);
200 }
201
202 #ifdef VIMAGE
203 static void
udp_destroy(void * unused __unused)204 udp_destroy(void *unused __unused)
205 {
206
207 in_pcbinfo_destroy(&V_udbinfo);
208 in_pcbinfo_destroy(&V_ulitecbinfo);
209 }
210 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
211 #endif
212
213 #ifdef INET
214 /*
215 * Subroutine of udp_input(), which appends the provided mbuf chain to the
216 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that
217 * contains the source address. If the socket ends up being an IPv6 socket,
218 * udp_append() will convert to a sockaddr_in6 before passing the address
219 * into the socket code.
220 *
221 * In the normal case udp_append() will return 0, indicating that you
222 * must unlock the inp. However if a tunneling protocol is in place we increment
223 * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
224 * then decrement the reference count. If the inp_rele returns 1, indicating the
225 * inp is gone, we return that to the caller to tell them *not* to unlock
226 * the inp. In the case of multi-cast this will cause the distribution
227 * to stop (though most tunneling protocols known currently do *not* use
228 * multicast).
229 */
230 static int
udp_append(struct inpcb * inp,struct ip * ip,struct mbuf * n,int off,struct sockaddr_in * udp_in)231 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
232 struct sockaddr_in *udp_in)
233 {
234 struct sockaddr *append_sa;
235 struct socket *so;
236 struct mbuf *tmpopts, *opts = NULL;
237 #ifdef INET6
238 struct sockaddr_in6 udp_in6;
239 #endif
240 struct udpcb *up;
241 bool filtered;
242
243 INP_LOCK_ASSERT(inp);
244
245 /*
246 * Engage the tunneling protocol.
247 */
248 up = intoudpcb(inp);
249 if (up->u_tun_func != NULL) {
250 in_pcbref(inp);
251 INP_RUNLOCK(inp);
252 filtered = (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
253 up->u_tun_ctx);
254 INP_RLOCK(inp);
255 if (filtered)
256 return (in_pcbrele_rlocked(inp));
257 }
258
259 off += sizeof(struct udphdr);
260
261 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
262 /* Check AH/ESP integrity. */
263 if (IPSEC_ENABLED(ipv4) &&
264 IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
265 m_freem(n);
266 return (0);
267 }
268 if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
269 if (IPSEC_ENABLED(ipv4) &&
270 UDPENCAP_INPUT(ipv4, n, off, AF_INET) != 0)
271 return (0); /* Consumed. */
272 }
273 #endif /* IPSEC */
274 #ifdef MAC
275 if (mac_inpcb_check_deliver(inp, n) != 0) {
276 m_freem(n);
277 return (0);
278 }
279 #endif /* MAC */
280 if (inp->inp_flags & INP_CONTROLOPTS ||
281 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
282 #ifdef INET6
283 if (inp->inp_vflag & INP_IPV6)
284 (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
285 else
286 #endif /* INET6 */
287 ip_savecontrol(inp, &opts, ip, n);
288 }
289 if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
290 tmpopts = sbcreatecontrol(&udp_in[1],
291 sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP,
292 M_NOWAIT);
293 if (tmpopts) {
294 if (opts) {
295 tmpopts->m_next = opts;
296 opts = tmpopts;
297 } else
298 opts = tmpopts;
299 }
300 }
301 #ifdef INET6
302 if (inp->inp_vflag & INP_IPV6) {
303 bzero(&udp_in6, sizeof(udp_in6));
304 udp_in6.sin6_len = sizeof(udp_in6);
305 udp_in6.sin6_family = AF_INET6;
306 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
307 append_sa = (struct sockaddr *)&udp_in6;
308 } else
309 #endif /* INET6 */
310 append_sa = (struct sockaddr *)&udp_in[0];
311 m_adj(n, off);
312
313 so = inp->inp_socket;
314 SOCKBUF_LOCK(&so->so_rcv);
315 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
316 soroverflow_locked(so);
317 m_freem(n);
318 if (opts)
319 m_freem(opts);
320 UDPSTAT_INC(udps_fullsock);
321 } else
322 sorwakeup_locked(so);
323 return (0);
324 }
325
326 static bool
udp_multi_match(const struct inpcb * inp,void * v)327 udp_multi_match(const struct inpcb *inp, void *v)
328 {
329 struct ip *ip = v;
330 struct udphdr *uh = (struct udphdr *)(ip + 1);
331
332 if (inp->inp_lport != uh->uh_dport)
333 return (false);
334 #ifdef INET6
335 if ((inp->inp_vflag & INP_IPV4) == 0)
336 return (false);
337 #endif
338 if (inp->inp_laddr.s_addr != INADDR_ANY &&
339 inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
340 return (false);
341 if (inp->inp_faddr.s_addr != INADDR_ANY &&
342 inp->inp_faddr.s_addr != ip->ip_src.s_addr)
343 return (false);
344 if (inp->inp_fport != 0 &&
345 inp->inp_fport != uh->uh_sport)
346 return (false);
347
348 return (true);
349 }
350
351 static int
udp_multi_input(struct mbuf * m,int proto,struct sockaddr_in * udp_in)352 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in)
353 {
354 struct ip *ip = mtod(m, struct ip *);
355 struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
356 INPLOOKUP_RLOCKPCB, udp_multi_match, ip);
357 #ifdef KDTRACE_HOOKS
358 struct udphdr *uh = (struct udphdr *)(ip + 1);
359 #endif
360 struct inpcb *inp;
361 struct mbuf *n;
362 int appends = 0;
363
364 MPASS(ip->ip_hl == sizeof(struct ip) >> 2);
365
366 while ((inp = inp_next(&inpi)) != NULL) {
367 /*
368 * XXXRW: Because we weren't holding either the inpcb
369 * or the hash lock when we checked for a match
370 * before, we should probably recheck now that the
371 * inpcb lock is held.
372 */
373 /*
374 * Handle socket delivery policy for any-source
375 * and source-specific multicast. [RFC3678]
376 */
377 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
378 struct ip_moptions *imo;
379 struct sockaddr_in group;
380 int blocked;
381
382 imo = inp->inp_moptions;
383 if (imo == NULL)
384 continue;
385 bzero(&group, sizeof(struct sockaddr_in));
386 group.sin_len = sizeof(struct sockaddr_in);
387 group.sin_family = AF_INET;
388 group.sin_addr = ip->ip_dst;
389
390 blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif,
391 (struct sockaddr *)&group,
392 (struct sockaddr *)&udp_in[0]);
393 if (blocked != MCAST_PASS) {
394 if (blocked == MCAST_NOTGMEMBER)
395 IPSTAT_INC(ips_notmember);
396 if (blocked == MCAST_NOTSMEMBER ||
397 blocked == MCAST_MUTED)
398 UDPSTAT_INC(udps_filtermcast);
399 continue;
400 }
401 }
402 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
403 if (proto == IPPROTO_UDPLITE)
404 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
405 else
406 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
407 if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) {
408 break;
409 } else
410 appends++;
411 }
412 /*
413 * Don't look for additional matches if this one does
414 * not have either the SO_REUSEPORT or SO_REUSEADDR
415 * socket options set. This heuristic avoids
416 * searching through all pcbs in the common case of a
417 * non-shared port. It assumes that an application
418 * will never clear these options after setting them.
419 */
420 if ((inp->inp_socket->so_options &
421 (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
422 INP_RUNLOCK(inp);
423 break;
424 }
425 }
426
427 if (appends == 0) {
428 /*
429 * No matching pcb found; discard datagram. (No need
430 * to send an ICMP Port Unreachable for a broadcast
431 * or multicast datgram.)
432 */
433 UDPSTAT_INC(udps_noport);
434 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
435 UDPSTAT_INC(udps_noportmcast);
436 else
437 UDPSTAT_INC(udps_noportbcast);
438 }
439 m_freem(m);
440
441 return (IPPROTO_DONE);
442 }
443
444 static int
udp_input(struct mbuf ** mp,int * offp,int proto)445 udp_input(struct mbuf **mp, int *offp, int proto)
446 {
447 struct ip *ip;
448 struct udphdr *uh;
449 struct ifnet *ifp;
450 struct inpcb *inp;
451 uint16_t len, ip_len;
452 struct inpcbinfo *pcbinfo;
453 struct sockaddr_in udp_in[2];
454 struct mbuf *m;
455 struct m_tag *fwd_tag;
456 int cscov_partial, iphlen;
457
458 m = *mp;
459 iphlen = *offp;
460 ifp = m->m_pkthdr.rcvif;
461 *mp = NULL;
462 UDPSTAT_INC(udps_ipackets);
463
464 /*
465 * Strip IP options, if any; should skip this, make available to
466 * user, and use on returned packets, but we don't yet have a way to
467 * check the checksum with options still present.
468 */
469 if (iphlen > sizeof (struct ip)) {
470 ip_stripoptions(m);
471 iphlen = sizeof(struct ip);
472 }
473
474 /*
475 * Get IP and UDP header together in first mbuf.
476 */
477 if (m->m_len < iphlen + sizeof(struct udphdr)) {
478 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
479 UDPSTAT_INC(udps_hdrops);
480 return (IPPROTO_DONE);
481 }
482 }
483 ip = mtod(m, struct ip *);
484 uh = (struct udphdr *)((caddr_t)ip + iphlen);
485 cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
486
487 /*
488 * Destination port of 0 is illegal, based on RFC768.
489 */
490 if (uh->uh_dport == 0)
491 goto badunlocked;
492
493 /*
494 * Construct sockaddr format source address. Stuff source address
495 * and datagram in user buffer.
496 */
497 bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
498 udp_in[0].sin_len = sizeof(struct sockaddr_in);
499 udp_in[0].sin_family = AF_INET;
500 udp_in[0].sin_port = uh->uh_sport;
501 udp_in[0].sin_addr = ip->ip_src;
502 udp_in[1].sin_len = sizeof(struct sockaddr_in);
503 udp_in[1].sin_family = AF_INET;
504 udp_in[1].sin_port = uh->uh_dport;
505 udp_in[1].sin_addr = ip->ip_dst;
506
507 /*
508 * Make mbuf data length reflect UDP length. If not enough data to
509 * reflect UDP length, drop.
510 */
511 len = ntohs((u_short)uh->uh_ulen);
512 ip_len = ntohs(ip->ip_len) - iphlen;
513 if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
514 /* Zero means checksum over the complete packet. */
515 if (len == 0)
516 len = ip_len;
517 cscov_partial = 0;
518 }
519 if (ip_len != len) {
520 if (len > ip_len || len < sizeof(struct udphdr)) {
521 UDPSTAT_INC(udps_badlen);
522 goto badunlocked;
523 }
524 if (proto == IPPROTO_UDP)
525 m_adj(m, len - ip_len);
526 }
527
528 /*
529 * Checksum extended UDP header and data.
530 */
531 if (uh->uh_sum) {
532 u_short uh_sum;
533
534 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
535 !cscov_partial) {
536 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
537 uh_sum = m->m_pkthdr.csum_data;
538 else
539 uh_sum = in_pseudo(ip->ip_src.s_addr,
540 ip->ip_dst.s_addr, htonl((u_short)len +
541 m->m_pkthdr.csum_data + proto));
542 uh_sum ^= 0xffff;
543 } else {
544 char b[offsetof(struct ipovly, ih_src)];
545 struct ipovly *ipov = (struct ipovly *)ip;
546
547 bcopy(ipov, b, sizeof(b));
548 bzero(ipov, sizeof(ipov->ih_x1));
549 ipov->ih_len = (proto == IPPROTO_UDP) ?
550 uh->uh_ulen : htons(ip_len);
551 uh_sum = in_cksum(m, len + sizeof (struct ip));
552 bcopy(b, ipov, sizeof(b));
553 }
554 if (uh_sum) {
555 UDPSTAT_INC(udps_badsum);
556 m_freem(m);
557 return (IPPROTO_DONE);
558 }
559 } else {
560 if (proto == IPPROTO_UDP) {
561 UDPSTAT_INC(udps_nosum);
562 } else {
563 /* UDPLite requires a checksum */
564 /* XXX: What is the right UDPLite MIB counter here? */
565 m_freem(m);
566 return (IPPROTO_DONE);
567 }
568 }
569
570 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
571 in_broadcast(ip->ip_dst, ifp))
572 return (udp_multi_input(m, proto, udp_in));
573
574 pcbinfo = udp_get_inpcbinfo(proto);
575
576 /*
577 * Locate pcb for datagram.
578 *
579 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
580 */
581 if ((m->m_flags & M_IP_NEXTHOP) &&
582 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
583 struct sockaddr_in *next_hop;
584
585 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
586
587 /*
588 * Transparently forwarded. Pretend to be the destination.
589 * Already got one like this?
590 */
591 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
592 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
593 if (!inp) {
594 /*
595 * It's new. Try to find the ambushing socket.
596 * Because we've rewritten the destination address,
597 * any hardware-generated hash is ignored.
598 */
599 inp = in_pcblookup(pcbinfo, ip->ip_src,
600 uh->uh_sport, next_hop->sin_addr,
601 next_hop->sin_port ? htons(next_hop->sin_port) :
602 uh->uh_dport, INPLOOKUP_WILDCARD |
603 INPLOOKUP_RLOCKPCB, ifp);
604 }
605 /* Remove the tag from the packet. We don't need it anymore. */
606 m_tag_delete(m, fwd_tag);
607 m->m_flags &= ~M_IP_NEXTHOP;
608 } else
609 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
610 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
611 INPLOOKUP_RLOCKPCB, ifp, m);
612 if (inp == NULL) {
613 if (V_udp_log_in_vain) {
614 char src[INET_ADDRSTRLEN];
615 char dst[INET_ADDRSTRLEN];
616
617 log(LOG_INFO,
618 "Connection attempt to UDP %s:%d from %s:%d\n",
619 inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
620 inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
621 }
622 if (proto == IPPROTO_UDPLITE)
623 UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
624 else
625 UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
626 UDPSTAT_INC(udps_noport);
627 if (m->m_flags & (M_BCAST | M_MCAST)) {
628 UDPSTAT_INC(udps_noportbcast);
629 goto badunlocked;
630 }
631 if (V_udp_blackhole && (V_udp_blackhole_local ||
632 !in_localip(ip->ip_src)))
633 goto badunlocked;
634 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
635 goto badunlocked;
636 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
637 return (IPPROTO_DONE);
638 }
639
640 /*
641 * Check the minimum TTL for socket.
642 */
643 INP_RLOCK_ASSERT(inp);
644 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
645 if (proto == IPPROTO_UDPLITE)
646 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
647 else
648 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
649 INP_RUNLOCK(inp);
650 m_freem(m);
651 return (IPPROTO_DONE);
652 }
653 if (cscov_partial) {
654 struct udpcb *up;
655
656 up = intoudpcb(inp);
657 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
658 INP_RUNLOCK(inp);
659 m_freem(m);
660 return (IPPROTO_DONE);
661 }
662 }
663
664 if (proto == IPPROTO_UDPLITE)
665 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
666 else
667 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
668 if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
669 INP_RUNLOCK(inp);
670 return (IPPROTO_DONE);
671
672 badunlocked:
673 m_freem(m);
674 return (IPPROTO_DONE);
675 }
676 #endif /* INET */
677
678 /*
679 * Notify a udp user of an asynchronous error; just wake up so that they can
680 * collect error status.
681 */
682 struct inpcb *
udp_notify(struct inpcb * inp,int errno)683 udp_notify(struct inpcb *inp, int errno)
684 {
685
686 INP_WLOCK_ASSERT(inp);
687 if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
688 errno == EHOSTDOWN) && inp->inp_route.ro_nh) {
689 NH_FREE(inp->inp_route.ro_nh);
690 inp->inp_route.ro_nh = (struct nhop_object *)NULL;
691 }
692
693 inp->inp_socket->so_error = errno;
694 sorwakeup(inp->inp_socket);
695 sowwakeup(inp->inp_socket);
696 return (inp);
697 }
698
699 #ifdef INET
700 static void
udp_common_ctlinput(struct icmp * icmp,struct inpcbinfo * pcbinfo)701 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo)
702 {
703 struct ip *ip = &icmp->icmp_ip;
704 struct udphdr *uh;
705 struct inpcb *inp;
706
707 if (icmp_errmap(icmp) == 0)
708 return;
709
710 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
711 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src,
712 uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
713 if (inp != NULL) {
714 INP_WLOCK_ASSERT(inp);
715 if (inp->inp_socket != NULL)
716 udp_notify(inp, icmp_errmap(icmp));
717 INP_WUNLOCK(inp);
718 } else {
719 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport,
720 ip->ip_src, uh->uh_sport,
721 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
722 if (inp != NULL) {
723 struct udpcb *up;
724 udp_tun_icmp_t *func;
725
726 up = intoudpcb(inp);
727 func = up->u_icmp_func;
728 INP_RUNLOCK(inp);
729 if (func != NULL)
730 func(icmp);
731 }
732 }
733 }
734
735 static void
udp_ctlinput(struct icmp * icmp)736 udp_ctlinput(struct icmp *icmp)
737 {
738
739 return (udp_common_ctlinput(icmp, &V_udbinfo));
740 }
741
742 static void
udplite_ctlinput(struct icmp * icmp)743 udplite_ctlinput(struct icmp *icmp)
744 {
745
746 return (udp_common_ctlinput(icmp, &V_ulitecbinfo));
747 }
748 #endif /* INET */
749
750 static int
udp_pcblist(SYSCTL_HANDLER_ARGS)751 udp_pcblist(SYSCTL_HANDLER_ARGS)
752 {
753 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_udbinfo,
754 INPLOOKUP_RLOCKPCB);
755 struct xinpgen xig;
756 struct inpcb *inp;
757 int error;
758
759 if (req->newptr != 0)
760 return (EPERM);
761
762 if (req->oldptr == 0) {
763 int n;
764
765 n = V_udbinfo.ipi_count;
766 n += imax(n / 8, 10);
767 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
768 return (0);
769 }
770
771 if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
772 return (error);
773
774 bzero(&xig, sizeof(xig));
775 xig.xig_len = sizeof xig;
776 xig.xig_count = V_udbinfo.ipi_count;
777 xig.xig_gen = V_udbinfo.ipi_gencnt;
778 xig.xig_sogen = so_gencnt;
779 error = SYSCTL_OUT(req, &xig, sizeof xig);
780 if (error)
781 return (error);
782
783 while ((inp = inp_next(&inpi)) != NULL) {
784 if (inp->inp_gencnt <= xig.xig_gen &&
785 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
786 struct xinpcb xi;
787
788 in_pcbtoxinpcb(inp, &xi);
789 error = SYSCTL_OUT(req, &xi, sizeof xi);
790 if (error) {
791 INP_RUNLOCK(inp);
792 break;
793 }
794 }
795 }
796
797 if (!error) {
798 /*
799 * Give the user an updated idea of our state. If the
800 * generation differs from what we told her before, she knows
801 * that something happened while we were processing this
802 * request, and it might be necessary to retry.
803 */
804 xig.xig_gen = V_udbinfo.ipi_gencnt;
805 xig.xig_sogen = so_gencnt;
806 xig.xig_count = V_udbinfo.ipi_count;
807 error = SYSCTL_OUT(req, &xig, sizeof xig);
808 }
809
810 return (error);
811 }
812
813 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
814 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
815 udp_pcblist, "S,xinpcb",
816 "List of active UDP sockets");
817
818 #ifdef INET
819 static int
udp_getcred(SYSCTL_HANDLER_ARGS)820 udp_getcred(SYSCTL_HANDLER_ARGS)
821 {
822 struct xucred xuc;
823 struct sockaddr_in addrs[2];
824 struct epoch_tracker et;
825 struct inpcb *inp;
826 int error;
827
828 error = priv_check(req->td, PRIV_NETINET_GETCRED);
829 if (error)
830 return (error);
831 error = SYSCTL_IN(req, addrs, sizeof(addrs));
832 if (error)
833 return (error);
834 NET_EPOCH_ENTER(et);
835 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
836 addrs[0].sin_addr, addrs[0].sin_port,
837 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
838 NET_EPOCH_EXIT(et);
839 if (inp != NULL) {
840 INP_RLOCK_ASSERT(inp);
841 if (inp->inp_socket == NULL)
842 error = ENOENT;
843 if (error == 0)
844 error = cr_canseeinpcb(req->td->td_ucred, inp);
845 if (error == 0)
846 cru2x(inp->inp_cred, &xuc);
847 INP_RUNLOCK(inp);
848 } else
849 error = ENOENT;
850 if (error == 0)
851 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
852 return (error);
853 }
854
855 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
856 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
857 0, 0, udp_getcred, "S,xucred",
858 "Get the xucred of a UDP connection");
859 #endif /* INET */
860
861 int
udp_ctloutput(struct socket * so,struct sockopt * sopt)862 udp_ctloutput(struct socket *so, struct sockopt *sopt)
863 {
864 struct inpcb *inp;
865 struct udpcb *up;
866 int isudplite, error, optval;
867
868 error = 0;
869 isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
870 inp = sotoinpcb(so);
871 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
872 INP_WLOCK(inp);
873 if (sopt->sopt_level != so->so_proto->pr_protocol) {
874 #ifdef INET6
875 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
876 INP_WUNLOCK(inp);
877 error = ip6_ctloutput(so, sopt);
878 }
879 #endif
880 #if defined(INET) && defined(INET6)
881 else
882 #endif
883 #ifdef INET
884 {
885 INP_WUNLOCK(inp);
886 error = ip_ctloutput(so, sopt);
887 }
888 #endif
889 return (error);
890 }
891
892 switch (sopt->sopt_dir) {
893 case SOPT_SET:
894 switch (sopt->sopt_name) {
895 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
896 #if defined(INET) || defined(INET6)
897 case UDP_ENCAP:
898 #ifdef INET
899 if (INP_SOCKAF(so) == AF_INET) {
900 if (!IPSEC_ENABLED(ipv4)) {
901 INP_WUNLOCK(inp);
902 return (ENOPROTOOPT);
903 }
904 error = UDPENCAP_PCBCTL(ipv4, inp, sopt);
905 break;
906 }
907 #endif /* INET */
908 #ifdef INET6
909 if (INP_SOCKAF(so) == AF_INET6) {
910 if (!IPSEC_ENABLED(ipv6)) {
911 INP_WUNLOCK(inp);
912 return (ENOPROTOOPT);
913 }
914 error = UDPENCAP_PCBCTL(ipv6, inp, sopt);
915 break;
916 }
917 #endif /* INET6 */
918 INP_WUNLOCK(inp);
919 return (EINVAL);
920 #endif /* INET || INET6 */
921
922 #endif /* IPSEC */
923 case UDPLITE_SEND_CSCOV:
924 case UDPLITE_RECV_CSCOV:
925 if (!isudplite) {
926 INP_WUNLOCK(inp);
927 error = ENOPROTOOPT;
928 break;
929 }
930 INP_WUNLOCK(inp);
931 error = sooptcopyin(sopt, &optval, sizeof(optval),
932 sizeof(optval));
933 if (error != 0)
934 break;
935 inp = sotoinpcb(so);
936 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
937 INP_WLOCK(inp);
938 up = intoudpcb(inp);
939 KASSERT(up != NULL, ("%s: up == NULL", __func__));
940 if ((optval != 0 && optval < 8) || (optval > 65535)) {
941 INP_WUNLOCK(inp);
942 error = EINVAL;
943 break;
944 }
945 if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
946 up->u_txcslen = optval;
947 else
948 up->u_rxcslen = optval;
949 INP_WUNLOCK(inp);
950 break;
951 default:
952 INP_WUNLOCK(inp);
953 error = ENOPROTOOPT;
954 break;
955 }
956 break;
957 case SOPT_GET:
958 switch (sopt->sopt_name) {
959 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
960 #if defined(INET) || defined(INET6)
961 case UDP_ENCAP:
962 #ifdef INET
963 if (INP_SOCKAF(so) == AF_INET) {
964 if (!IPSEC_ENABLED(ipv4)) {
965 INP_WUNLOCK(inp);
966 return (ENOPROTOOPT);
967 }
968 error = UDPENCAP_PCBCTL(ipv4, inp, sopt);
969 break;
970 }
971 #endif /* INET */
972 #ifdef INET6
973 if (INP_SOCKAF(so) == AF_INET6) {
974 if (!IPSEC_ENABLED(ipv6)) {
975 INP_WUNLOCK(inp);
976 return (ENOPROTOOPT);
977 }
978 error = UDPENCAP_PCBCTL(ipv6, inp, sopt);
979 break;
980 }
981 #endif /* INET6 */
982 INP_WUNLOCK(inp);
983 return (EINVAL);
984 #endif /* INET || INET6 */
985
986 #endif /* IPSEC */
987 case UDPLITE_SEND_CSCOV:
988 case UDPLITE_RECV_CSCOV:
989 if (!isudplite) {
990 INP_WUNLOCK(inp);
991 error = ENOPROTOOPT;
992 break;
993 }
994 up = intoudpcb(inp);
995 KASSERT(up != NULL, ("%s: up == NULL", __func__));
996 if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
997 optval = up->u_txcslen;
998 else
999 optval = up->u_rxcslen;
1000 INP_WUNLOCK(inp);
1001 error = sooptcopyout(sopt, &optval, sizeof(optval));
1002 break;
1003 default:
1004 INP_WUNLOCK(inp);
1005 error = ENOPROTOOPT;
1006 break;
1007 }
1008 break;
1009 }
1010 return (error);
1011 }
1012
1013 #ifdef INET
1014 #ifdef INET6
1015 /* The logic here is derived from ip6_setpktopt(). See comments there. */
1016 static int
udp_v4mapped_pktinfo(struct cmsghdr * cm,struct sockaddr_in * src,struct inpcb * inp,int flags)1017 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src,
1018 struct inpcb *inp, int flags)
1019 {
1020 struct ifnet *ifp;
1021 struct in6_pktinfo *pktinfo;
1022 struct in_addr ia;
1023
1024 if ((flags & PRUS_IPV6) == 0)
1025 return (0);
1026
1027 if (cm->cmsg_level != IPPROTO_IPV6)
1028 return (0);
1029
1030 if (cm->cmsg_type != IPV6_2292PKTINFO &&
1031 cm->cmsg_type != IPV6_PKTINFO)
1032 return (0);
1033
1034 if (cm->cmsg_len !=
1035 CMSG_LEN(sizeof(struct in6_pktinfo)))
1036 return (EINVAL);
1037
1038 pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm);
1039 if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) &&
1040 !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr))
1041 return (EINVAL);
1042
1043 /* Validate the interface index if specified. */
1044 if (pktinfo->ipi6_ifindex) {
1045 struct epoch_tracker et;
1046
1047 NET_EPOCH_ENTER(et);
1048 ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
1049 NET_EPOCH_EXIT(et); /* XXXGL: unsafe ifp */
1050 if (ifp == NULL)
1051 return (ENXIO);
1052 } else
1053 ifp = NULL;
1054 if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
1055 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1056 if (in_ifhasaddr(ifp, ia) == 0)
1057 return (EADDRNOTAVAIL);
1058 }
1059
1060 bzero(src, sizeof(*src));
1061 src->sin_family = AF_INET;
1062 src->sin_len = sizeof(*src);
1063 src->sin_port = inp->inp_lport;
1064 src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1065
1066 return (0);
1067 }
1068 #endif /* INET6 */
1069
1070 int
udp_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct thread * td)1071 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1072 struct mbuf *control, struct thread *td)
1073 {
1074 struct inpcb *inp;
1075 struct udpiphdr *ui;
1076 int len, error = 0;
1077 struct in_addr faddr, laddr;
1078 struct cmsghdr *cm;
1079 struct inpcbinfo *pcbinfo;
1080 struct sockaddr_in *sin, src;
1081 struct epoch_tracker et;
1082 int cscov_partial = 0;
1083 int ipflags = 0;
1084 u_short fport, lport;
1085 u_char tos, vflagsav;
1086 uint8_t pr;
1087 uint16_t cscov = 0;
1088 uint32_t flowid = 0;
1089 uint8_t flowtype = M_HASHTYPE_NONE;
1090 bool use_cached_route;
1091
1092 inp = sotoinpcb(so);
1093 KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1094
1095 if (addr != NULL) {
1096 if (addr->sa_family != AF_INET)
1097 error = EAFNOSUPPORT;
1098 else if (addr->sa_len != sizeof(struct sockaddr_in))
1099 error = EINVAL;
1100 if (__predict_false(error != 0)) {
1101 m_freem(control);
1102 m_freem(m);
1103 return (error);
1104 }
1105 }
1106
1107 len = m->m_pkthdr.len;
1108 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1109 if (control)
1110 m_freem(control);
1111 m_freem(m);
1112 return (EMSGSIZE);
1113 }
1114
1115 src.sin_family = 0;
1116 sin = (struct sockaddr_in *)addr;
1117
1118 /*
1119 * udp_send() may need to temporarily bind or connect the current
1120 * inpcb. As such, we don't know up front whether we will need the
1121 * pcbinfo lock or not. Do any work to decide what is needed up
1122 * front before acquiring any locks.
1123 *
1124 * We will need network epoch in either case, to safely lookup into
1125 * pcb hash.
1126 */
1127 use_cached_route = sin == NULL || (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0);
1128 if (use_cached_route || (flags & PRUS_IPV6) != 0)
1129 INP_WLOCK(inp);
1130 else
1131 INP_RLOCK(inp);
1132 NET_EPOCH_ENTER(et);
1133 tos = inp->inp_ip_tos;
1134 if (control != NULL) {
1135 /*
1136 * XXX: Currently, we assume all the optional information is
1137 * stored in a single mbuf.
1138 */
1139 if (control->m_next) {
1140 m_freem(control);
1141 error = EINVAL;
1142 goto release;
1143 }
1144 for (; control->m_len > 0;
1145 control->m_data += CMSG_ALIGN(cm->cmsg_len),
1146 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1147 cm = mtod(control, struct cmsghdr *);
1148 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1149 || cm->cmsg_len > control->m_len) {
1150 error = EINVAL;
1151 break;
1152 }
1153 #ifdef INET6
1154 error = udp_v4mapped_pktinfo(cm, &src, inp, flags);
1155 if (error != 0)
1156 break;
1157 #endif
1158 if (cm->cmsg_level != IPPROTO_IP)
1159 continue;
1160
1161 switch (cm->cmsg_type) {
1162 case IP_SENDSRCADDR:
1163 if (cm->cmsg_len !=
1164 CMSG_LEN(sizeof(struct in_addr))) {
1165 error = EINVAL;
1166 break;
1167 }
1168 bzero(&src, sizeof(src));
1169 src.sin_family = AF_INET;
1170 src.sin_len = sizeof(src);
1171 src.sin_port = inp->inp_lport;
1172 src.sin_addr =
1173 *(struct in_addr *)CMSG_DATA(cm);
1174 break;
1175
1176 case IP_TOS:
1177 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1178 error = EINVAL;
1179 break;
1180 }
1181 tos = *(u_char *)CMSG_DATA(cm);
1182 break;
1183
1184 case IP_FLOWID:
1185 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1186 error = EINVAL;
1187 break;
1188 }
1189 flowid = *(uint32_t *) CMSG_DATA(cm);
1190 break;
1191
1192 case IP_FLOWTYPE:
1193 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1194 error = EINVAL;
1195 break;
1196 }
1197 flowtype = *(uint32_t *) CMSG_DATA(cm);
1198 break;
1199
1200 #ifdef RSS
1201 case IP_RSSBUCKETID:
1202 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1203 error = EINVAL;
1204 break;
1205 }
1206 /* This is just a placeholder for now */
1207 break;
1208 #endif /* RSS */
1209 default:
1210 error = ENOPROTOOPT;
1211 break;
1212 }
1213 if (error)
1214 break;
1215 }
1216 m_freem(control);
1217 control = NULL;
1218 }
1219 if (error)
1220 goto release;
1221
1222 pr = inp->inp_socket->so_proto->pr_protocol;
1223 pcbinfo = udp_get_inpcbinfo(pr);
1224
1225 /*
1226 * If the IP_SENDSRCADDR control message was specified, override the
1227 * source address for this datagram. Its use is invalidated if the
1228 * address thus specified is incomplete or clobbers other inpcbs.
1229 */
1230 laddr = inp->inp_laddr;
1231 lport = inp->inp_lport;
1232 if (src.sin_family == AF_INET) {
1233 if ((lport == 0) ||
1234 (laddr.s_addr == INADDR_ANY &&
1235 src.sin_addr.s_addr == INADDR_ANY)) {
1236 error = EINVAL;
1237 goto release;
1238 }
1239 if ((flags & PRUS_IPV6) != 0) {
1240 vflagsav = inp->inp_vflag;
1241 inp->inp_vflag |= INP_IPV4;
1242 inp->inp_vflag &= ~INP_IPV6;
1243 }
1244 INP_HASH_WLOCK(pcbinfo);
1245 error = in_pcbbind_setup(inp, &src, &laddr.s_addr, &lport,
1246 td->td_ucred);
1247 INP_HASH_WUNLOCK(pcbinfo);
1248 if ((flags & PRUS_IPV6) != 0)
1249 inp->inp_vflag = vflagsav;
1250 if (error)
1251 goto release;
1252 }
1253
1254 /*
1255 * If a UDP socket has been connected, then a local address/port will
1256 * have been selected and bound.
1257 *
1258 * If a UDP socket has not been connected to, then an explicit
1259 * destination address must be used, in which case a local
1260 * address/port may not have been selected and bound.
1261 */
1262 if (sin != NULL) {
1263 INP_LOCK_ASSERT(inp);
1264 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1265 error = EISCONN;
1266 goto release;
1267 }
1268
1269 /*
1270 * Jail may rewrite the destination address, so let it do
1271 * that before we use it.
1272 */
1273 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1274 if (error)
1275 goto release;
1276
1277 /*
1278 * If a local address or port hasn't yet been selected, or if
1279 * the destination address needs to be rewritten due to using
1280 * a special INADDR_ constant, invoke in_pcbconnect_setup()
1281 * to do the heavy lifting. Once a port is selected, we
1282 * commit the binding back to the socket; we also commit the
1283 * binding of the address if in jail.
1284 *
1285 * If we already have a valid binding and we're not
1286 * requesting a destination address rewrite, use a fast path.
1287 */
1288 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1289 inp->inp_lport == 0 ||
1290 sin->sin_addr.s_addr == INADDR_ANY ||
1291 sin->sin_addr.s_addr == INADDR_BROADCAST) {
1292 if ((flags & PRUS_IPV6) != 0) {
1293 vflagsav = inp->inp_vflag;
1294 inp->inp_vflag |= INP_IPV4;
1295 inp->inp_vflag &= ~INP_IPV6;
1296 }
1297 INP_HASH_WLOCK(pcbinfo);
1298 error = in_pcbconnect_setup(inp, sin, &laddr.s_addr,
1299 &lport, &faddr.s_addr, &fport, td->td_ucred);
1300 if ((flags & PRUS_IPV6) != 0)
1301 inp->inp_vflag = vflagsav;
1302 if (error) {
1303 INP_HASH_WUNLOCK(pcbinfo);
1304 goto release;
1305 }
1306
1307 /*
1308 * XXXRW: Why not commit the port if the address is
1309 * !INADDR_ANY?
1310 */
1311 /* Commit the local port if newly assigned. */
1312 if (inp->inp_laddr.s_addr == INADDR_ANY &&
1313 inp->inp_lport == 0) {
1314 INP_WLOCK_ASSERT(inp);
1315 /*
1316 * Remember addr if jailed, to prevent
1317 * rebinding.
1318 */
1319 if (prison_flag(td->td_ucred, PR_IP4))
1320 inp->inp_laddr = laddr;
1321 inp->inp_lport = lport;
1322 error = in_pcbinshash(inp);
1323 INP_HASH_WUNLOCK(pcbinfo);
1324 if (error != 0) {
1325 inp->inp_lport = 0;
1326 error = EAGAIN;
1327 goto release;
1328 }
1329 inp->inp_flags |= INP_ANONPORT;
1330 } else
1331 INP_HASH_WUNLOCK(pcbinfo);
1332 } else {
1333 faddr = sin->sin_addr;
1334 fport = sin->sin_port;
1335 }
1336 } else {
1337 INP_LOCK_ASSERT(inp);
1338 faddr = inp->inp_faddr;
1339 fport = inp->inp_fport;
1340 if (faddr.s_addr == INADDR_ANY) {
1341 error = ENOTCONN;
1342 goto release;
1343 }
1344 }
1345
1346 /*
1347 * Calculate data length and get a mbuf for UDP, IP, and possible
1348 * link-layer headers. Immediate slide the data pointer back forward
1349 * since we won't use that space at this layer.
1350 */
1351 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1352 if (m == NULL) {
1353 error = ENOBUFS;
1354 goto release;
1355 }
1356 m->m_data += max_linkhdr;
1357 m->m_len -= max_linkhdr;
1358 m->m_pkthdr.len -= max_linkhdr;
1359
1360 /*
1361 * Fill in mbuf with extended UDP header and addresses and length put
1362 * into network format.
1363 */
1364 ui = mtod(m, struct udpiphdr *);
1365 /*
1366 * Filling only those fields of udpiphdr that participate in the
1367 * checksum calculation. The rest must be zeroed and will be filled
1368 * later.
1369 */
1370 bzero(ui->ui_x1, sizeof(ui->ui_x1));
1371 ui->ui_pr = pr;
1372 ui->ui_src = laddr;
1373 ui->ui_dst = faddr;
1374 ui->ui_sport = lport;
1375 ui->ui_dport = fport;
1376 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1377 if (pr == IPPROTO_UDPLITE) {
1378 struct udpcb *up;
1379 uint16_t plen;
1380
1381 up = intoudpcb(inp);
1382 cscov = up->u_txcslen;
1383 plen = (u_short)len + sizeof(struct udphdr);
1384 if (cscov >= plen)
1385 cscov = 0;
1386 ui->ui_len = htons(plen);
1387 ui->ui_ulen = htons(cscov);
1388 /*
1389 * For UDP-Lite, checksum coverage length of zero means
1390 * the entire UDPLite packet is covered by the checksum.
1391 */
1392 cscov_partial = (cscov == 0) ? 0 : 1;
1393 }
1394
1395 if (inp->inp_socket->so_options & SO_DONTROUTE)
1396 ipflags |= IP_ROUTETOIF;
1397 if (inp->inp_socket->so_options & SO_BROADCAST)
1398 ipflags |= IP_ALLOWBROADCAST;
1399 if (inp->inp_flags & INP_ONESBCAST)
1400 ipflags |= IP_SENDONES;
1401
1402 #ifdef MAC
1403 mac_inpcb_create_mbuf(inp, m);
1404 #endif
1405
1406 /*
1407 * Set up checksum and output datagram.
1408 */
1409 ui->ui_sum = 0;
1410 if (pr == IPPROTO_UDPLITE) {
1411 if (inp->inp_flags & INP_ONESBCAST)
1412 faddr.s_addr = INADDR_BROADCAST;
1413 if (cscov_partial) {
1414 if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1415 ui->ui_sum = 0xffff;
1416 } else {
1417 if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1418 ui->ui_sum = 0xffff;
1419 }
1420 } else if (V_udp_cksum) {
1421 if (inp->inp_flags & INP_ONESBCAST)
1422 faddr.s_addr = INADDR_BROADCAST;
1423 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1424 htons((u_short)len + sizeof(struct udphdr) + pr));
1425 m->m_pkthdr.csum_flags = CSUM_UDP;
1426 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1427 }
1428 /*
1429 * After finishing the checksum computation, fill the remaining fields
1430 * of udpiphdr.
1431 */
1432 ((struct ip *)ui)->ip_v = IPVERSION;
1433 ((struct ip *)ui)->ip_tos = tos;
1434 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1435 if (inp->inp_flags & INP_DONTFRAG)
1436 ((struct ip *)ui)->ip_off |= htons(IP_DF);
1437 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;
1438 UDPSTAT_INC(udps_opackets);
1439
1440 /*
1441 * Setup flowid / RSS information for outbound socket.
1442 *
1443 * Once the UDP code decides to set a flowid some other way,
1444 * this allows the flowid to be overridden by userland.
1445 */
1446 if (flowtype != M_HASHTYPE_NONE) {
1447 m->m_pkthdr.flowid = flowid;
1448 M_HASHTYPE_SET(m, flowtype);
1449 }
1450 #if defined(ROUTE_MPATH) || defined(RSS)
1451 else if (CALC_FLOWID_OUTBOUND_SENDTO) {
1452 uint32_t hash_val, hash_type;
1453
1454 hash_val = fib4_calc_packet_hash(laddr, faddr,
1455 lport, fport, pr, &hash_type);
1456 m->m_pkthdr.flowid = hash_val;
1457 M_HASHTYPE_SET(m, hash_type);
1458 }
1459
1460 /*
1461 * Don't override with the inp cached flowid value.
1462 *
1463 * Depending upon the kind of send being done, the inp
1464 * flowid/flowtype values may actually not be appropriate
1465 * for this particular socket send.
1466 *
1467 * We should either leave the flowid at zero (which is what is
1468 * currently done) or set it to some software generated
1469 * hash value based on the packet contents.
1470 */
1471 ipflags |= IP_NODEFAULTFLOWID;
1472 #endif /* RSS */
1473
1474 if (pr == IPPROTO_UDPLITE)
1475 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1476 else
1477 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1478 error = ip_output(m, inp->inp_options,
1479 use_cached_route ? &inp->inp_route : NULL, ipflags,
1480 inp->inp_moptions, inp);
1481 INP_UNLOCK(inp);
1482 NET_EPOCH_EXIT(et);
1483 return (error);
1484
1485 release:
1486 INP_UNLOCK(inp);
1487 NET_EPOCH_EXIT(et);
1488 m_freem(m);
1489 return (error);
1490 }
1491
1492 void
udp_abort(struct socket * so)1493 udp_abort(struct socket *so)
1494 {
1495 struct inpcb *inp;
1496 struct inpcbinfo *pcbinfo;
1497
1498 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1499 inp = sotoinpcb(so);
1500 KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1501 INP_WLOCK(inp);
1502 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1503 INP_HASH_WLOCK(pcbinfo);
1504 in_pcbdisconnect(inp);
1505 INP_HASH_WUNLOCK(pcbinfo);
1506 soisdisconnected(so);
1507 }
1508 INP_WUNLOCK(inp);
1509 }
1510
1511 static int
udp_attach(struct socket * so,int proto,struct thread * td)1512 udp_attach(struct socket *so, int proto, struct thread *td)
1513 {
1514 static uint32_t udp_flowid;
1515 struct inpcbinfo *pcbinfo;
1516 struct inpcb *inp;
1517 struct udpcb *up;
1518 int error;
1519
1520 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1521 inp = sotoinpcb(so);
1522 KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1523 error = soreserve(so, udp_sendspace, udp_recvspace);
1524 if (error)
1525 return (error);
1526 error = in_pcballoc(so, pcbinfo);
1527 if (error)
1528 return (error);
1529
1530 inp = sotoinpcb(so);
1531 inp->inp_ip_ttl = V_ip_defttl;
1532 inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1533 inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1534 up = intoudpcb(inp);
1535 bzero(&up->u_start_zero, u_zero_size);
1536 INP_WUNLOCK(inp);
1537
1538 return (0);
1539 }
1540 #endif /* INET */
1541
1542 int
udp_set_kernel_tunneling(struct socket * so,udp_tun_func_t f,udp_tun_icmp_t i,void * ctx)1543 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1544 {
1545 struct inpcb *inp;
1546 struct udpcb *up;
1547
1548 KASSERT(so->so_type == SOCK_DGRAM,
1549 ("udp_set_kernel_tunneling: !dgram"));
1550 inp = sotoinpcb(so);
1551 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1552 INP_WLOCK(inp);
1553 up = intoudpcb(inp);
1554 if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) ||
1555 (up->u_icmp_func != NULL))) {
1556 INP_WUNLOCK(inp);
1557 return (EBUSY);
1558 }
1559 up->u_tun_func = f;
1560 up->u_icmp_func = i;
1561 up->u_tun_ctx = ctx;
1562 INP_WUNLOCK(inp);
1563 return (0);
1564 }
1565
1566 #ifdef INET
1567 static int
udp_bind(struct socket * so,struct sockaddr * nam,struct thread * td)1568 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1569 {
1570 struct inpcb *inp;
1571 struct inpcbinfo *pcbinfo;
1572 struct sockaddr_in *sinp;
1573 int error;
1574
1575 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1576 inp = sotoinpcb(so);
1577 KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1578
1579 sinp = (struct sockaddr_in *)nam;
1580 if (nam->sa_family != AF_INET) {
1581 /*
1582 * Preserve compatibility with old programs.
1583 */
1584 if (nam->sa_family != AF_UNSPEC ||
1585 nam->sa_len < offsetof(struct sockaddr_in, sin_zero) ||
1586 sinp->sin_addr.s_addr != INADDR_ANY)
1587 return (EAFNOSUPPORT);
1588 nam->sa_family = AF_INET;
1589 }
1590 if (nam->sa_len != sizeof(struct sockaddr_in))
1591 return (EINVAL);
1592
1593 INP_WLOCK(inp);
1594 INP_HASH_WLOCK(pcbinfo);
1595 error = in_pcbbind(inp, sinp, td->td_ucred);
1596 INP_HASH_WUNLOCK(pcbinfo);
1597 INP_WUNLOCK(inp);
1598 return (error);
1599 }
1600
1601 static void
udp_close(struct socket * so)1602 udp_close(struct socket *so)
1603 {
1604 struct inpcb *inp;
1605 struct inpcbinfo *pcbinfo;
1606
1607 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1608 inp = sotoinpcb(so);
1609 KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1610 INP_WLOCK(inp);
1611 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1612 INP_HASH_WLOCK(pcbinfo);
1613 in_pcbdisconnect(inp);
1614 INP_HASH_WUNLOCK(pcbinfo);
1615 soisdisconnected(so);
1616 }
1617 INP_WUNLOCK(inp);
1618 }
1619
1620 static int
udp_connect(struct socket * so,struct sockaddr * nam,struct thread * td)1621 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1622 {
1623 struct epoch_tracker et;
1624 struct inpcb *inp;
1625 struct inpcbinfo *pcbinfo;
1626 struct sockaddr_in *sin;
1627 int error;
1628
1629 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1630 inp = sotoinpcb(so);
1631 KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1632
1633 sin = (struct sockaddr_in *)nam;
1634 if (sin->sin_family != AF_INET)
1635 return (EAFNOSUPPORT);
1636 if (sin->sin_len != sizeof(*sin))
1637 return (EINVAL);
1638
1639 INP_WLOCK(inp);
1640 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1641 INP_WUNLOCK(inp);
1642 return (EISCONN);
1643 }
1644 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1645 if (error != 0) {
1646 INP_WUNLOCK(inp);
1647 return (error);
1648 }
1649 NET_EPOCH_ENTER(et);
1650 INP_HASH_WLOCK(pcbinfo);
1651 error = in_pcbconnect(inp, sin, td->td_ucred, true);
1652 INP_HASH_WUNLOCK(pcbinfo);
1653 NET_EPOCH_EXIT(et);
1654 if (error == 0)
1655 soisconnected(so);
1656 INP_WUNLOCK(inp);
1657 return (error);
1658 }
1659
1660 static void
udp_detach(struct socket * so)1661 udp_detach(struct socket *so)
1662 {
1663 struct inpcb *inp;
1664
1665 inp = sotoinpcb(so);
1666 KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1667 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1668 ("udp_detach: not disconnected"));
1669 INP_WLOCK(inp);
1670 in_pcbfree(inp);
1671 }
1672
1673 int
udp_disconnect(struct socket * so)1674 udp_disconnect(struct socket *so)
1675 {
1676 struct inpcb *inp;
1677 struct inpcbinfo *pcbinfo;
1678
1679 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1680 inp = sotoinpcb(so);
1681 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1682 INP_WLOCK(inp);
1683 if (inp->inp_faddr.s_addr == INADDR_ANY) {
1684 INP_WUNLOCK(inp);
1685 return (ENOTCONN);
1686 }
1687 INP_HASH_WLOCK(pcbinfo);
1688 in_pcbdisconnect(inp);
1689 INP_HASH_WUNLOCK(pcbinfo);
1690 SOCK_LOCK(so);
1691 so->so_state &= ~SS_ISCONNECTED; /* XXX */
1692 SOCK_UNLOCK(so);
1693 INP_WUNLOCK(inp);
1694 return (0);
1695 }
1696 #endif /* INET */
1697
1698 int
udp_shutdown(struct socket * so,enum shutdown_how how)1699 udp_shutdown(struct socket *so, enum shutdown_how how)
1700 {
1701 int error;
1702
1703 SOCK_LOCK(so);
1704 if (!(so->so_state & SS_ISCONNECTED))
1705 /*
1706 * POSIX mandates us to just return ENOTCONN when shutdown(2) is
1707 * invoked on a datagram sockets, however historically we would
1708 * actually tear socket down. This is known to be leveraged by
1709 * some applications to unblock process waiting in recv(2) by
1710 * other process that it shares that socket with. Try to meet
1711 * both backward-compatibility and POSIX requirements by forcing
1712 * ENOTCONN but still flushing buffers and performing wakeup(9).
1713 *
1714 * XXXGL: it remains unknown what applications expect this
1715 * behavior and is this isolated to unix/dgram or inet/dgram or
1716 * both. See: D10351, D3039.
1717 */
1718 error = ENOTCONN;
1719 else
1720 error = 0;
1721 SOCK_UNLOCK(so);
1722
1723 switch (how) {
1724 case SHUT_RD:
1725 sorflush(so);
1726 break;
1727 case SHUT_RDWR:
1728 sorflush(so);
1729 /* FALLTHROUGH */
1730 case SHUT_WR:
1731 socantsendmore(so);
1732 }
1733
1734 return (error);
1735 }
1736
1737 #ifdef INET
1738 #define UDP_PROTOSW \
1739 .pr_type = SOCK_DGRAM, \
1740 .pr_flags = PR_ATOMIC | PR_ADDR | PR_CAPATTACH, \
1741 .pr_ctloutput = udp_ctloutput, \
1742 .pr_abort = udp_abort, \
1743 .pr_attach = udp_attach, \
1744 .pr_bind = udp_bind, \
1745 .pr_connect = udp_connect, \
1746 .pr_control = in_control, \
1747 .pr_detach = udp_detach, \
1748 .pr_disconnect = udp_disconnect, \
1749 .pr_peeraddr = in_getpeeraddr, \
1750 .pr_send = udp_send, \
1751 .pr_soreceive = soreceive_dgram, \
1752 .pr_sosend = sosend_dgram, \
1753 .pr_shutdown = udp_shutdown, \
1754 .pr_sockaddr = in_getsockaddr, \
1755 .pr_sosetlabel = in_pcbsosetlabel, \
1756 .pr_close = udp_close
1757
1758 struct protosw udp_protosw = {
1759 .pr_protocol = IPPROTO_UDP,
1760 UDP_PROTOSW
1761 };
1762
1763 struct protosw udplite_protosw = {
1764 .pr_protocol = IPPROTO_UDPLITE,
1765 UDP_PROTOSW
1766 };
1767
1768 static void
udp_init(void * arg __unused)1769 udp_init(void *arg __unused)
1770 {
1771
1772 IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput);
1773 IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput);
1774 }
1775 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL);
1776 #endif /* INET */
1777