1 /*-
2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95
30 * $FreeBSD$
31 */
32
33 #include "opt_ipfw.h"
34 #include "opt_ipsec.h"
35 #include "opt_inet6.h"
36 #include "opt_mac.h"
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/domain.h>
41 #include <sys/eventhandler.h>
42 #include <sys/jail.h>
43 #include <sys/kernel.h>
44 #include <sys/lock.h>
45 #include <sys/mac.h>
46 #include <sys/malloc.h>
47 #include <sys/mbuf.h>
48 #include <sys/proc.h>
49 #include <sys/protosw.h>
50 #include <sys/signalvar.h>
51 #include <sys/socket.h>
52 #include <sys/socketvar.h>
53 #include <sys/sx.h>
54 #include <sys/sysctl.h>
55 #include <sys/syslog.h>
56
57 #include <vm/uma.h>
58
59 #include <net/if.h>
60 #include <net/route.h>
61
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/in_pcb.h>
65 #include <netinet/in_var.h>
66 #include <netinet/ip.h>
67 #ifdef INET6
68 #include <netinet/ip6.h>
69 #endif
70 #include <netinet/ip_icmp.h>
71 #include <netinet/icmp_var.h>
72 #include <netinet/ip_var.h>
73 #ifdef INET6
74 #include <netinet6/ip6_var.h>
75 #endif
76 #include <netinet/udp.h>
77 #include <netinet/udp_var.h>
78
79 #ifdef FAST_IPSEC
80 #include <netipsec/ipsec.h>
81 #endif /*FAST_IPSEC*/
82
83 #ifdef IPSEC
84 #include <netinet6/ipsec.h>
85 #endif /*IPSEC*/
86
87 #include <machine/in_cksum.h>
88
89 /*
90 * UDP protocol implementation.
91 * Per RFC 768, August, 1980.
92 */
93 #ifndef COMPAT_42
94 static int udpcksum = 1;
95 #else
96 static int udpcksum = 0; /* XXX */
97 #endif
98 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW,
99 &udpcksum, 0, "");
100
101 int log_in_vain = 0;
102 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
103 &log_in_vain, 0, "Log all incoming UDP packets");
104
105 static int blackhole = 0;
106 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW,
107 &blackhole, 0, "Do not send port unreachables for refused connects");
108
109 static int strict_mcast_mship = 0;
110 SYSCTL_INT(_net_inet_udp, OID_AUTO, strict_mcast_mship, CTLFLAG_RW,
111 &strict_mcast_mship, 0, "Only send multicast to member sockets");
112
113 struct inpcbhead udb; /* from udp_var.h */
114 #define udb6 udb /* for KAME src sync over BSD*'s */
115 struct inpcbinfo udbinfo;
116
117 #ifndef UDBHASHSIZE
118 #define UDBHASHSIZE 16
119 #endif
120
121 struct udpstat udpstat; /* from udp_var.h */
122 SYSCTL_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW,
123 &udpstat, udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
124
125 static void udp_append(struct inpcb *last, struct ip *ip, struct mbuf *n,
126 int off, struct sockaddr_in *udp_in);
127
128 static int udp_detach(struct socket *so);
129 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
130 struct mbuf *, struct thread *);
131
132 static void
133 udp_zone_change(void *tag)
134 {
135
136 uma_zone_set_max(udbinfo.ipi_zone, maxsockets);
137 }
138
139 static int
140 udp_inpcb_init(void *mem, int size, int flags)
141 {
142 struct inpcb *inp = mem;
143
144 INP_LOCK_INIT(inp, "inp", "udpinp");
145 return (0);
146 }
147
148 void
149 udp_init()
150 {
151 INP_INFO_LOCK_INIT(&udbinfo, "udp");
152 LIST_INIT(&udb);
153 udbinfo.listhead = &udb;
154 udbinfo.hashbase = hashinit(UDBHASHSIZE, M_PCB, &udbinfo.hashmask);
155 udbinfo.porthashbase = hashinit(UDBHASHSIZE, M_PCB,
156 &udbinfo.porthashmask);
157 udbinfo.ipi_zone = uma_zcreate("udpcb", sizeof(struct inpcb), NULL,
158 NULL, udp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
159 uma_zone_set_max(udbinfo.ipi_zone, maxsockets);
160 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
161 EVENTHANDLER_PRI_ANY);
162 }
163
164 void
165 udp_input(m, off)
166 register struct mbuf *m;
167 int off;
168 {
169 int iphlen = off;
170 register struct ip *ip;
171 register struct udphdr *uh;
172 register struct inpcb *inp;
173 int len;
174 struct ip save_ip;
175 struct sockaddr_in udp_in;
176 #ifdef IPFIREWALL_FORWARD
177 struct m_tag *fwd_tag;
178 #endif
179
180 udpstat.udps_ipackets++;
181
182 /*
183 * Strip IP options, if any; should skip this,
184 * make available to user, and use on returned packets,
185 * but we don't yet have a way to check the checksum
186 * with options still present.
187 */
188 if (iphlen > sizeof (struct ip)) {
189 ip_stripoptions(m, (struct mbuf *)0);
190 iphlen = sizeof(struct ip);
191 }
192
193 /*
194 * Get IP and UDP header together in first mbuf.
195 */
196 ip = mtod(m, struct ip *);
197 if (m->m_len < iphlen + sizeof(struct udphdr)) {
198 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) {
199 udpstat.udps_hdrops++;
200 return;
201 }
202 ip = mtod(m, struct ip *);
203 }
204 uh = (struct udphdr *)((caddr_t)ip + iphlen);
205
206 /* destination port of 0 is illegal, based on RFC768. */
207 if (uh->uh_dport == 0)
208 goto badunlocked;
209
210 /*
211 * Construct sockaddr format source address.
212 * Stuff source address and datagram in user buffer.
213 */
214 bzero(&udp_in, sizeof(udp_in));
215 udp_in.sin_len = sizeof(udp_in);
216 udp_in.sin_family = AF_INET;
217 udp_in.sin_port = uh->uh_sport;
218 udp_in.sin_addr = ip->ip_src;
219
220 /*
221 * Make mbuf data length reflect UDP length.
222 * If not enough data to reflect UDP length, drop.
223 */
224 len = ntohs((u_short)uh->uh_ulen);
225 if (ip->ip_len != len) {
226 if (len > ip->ip_len || len < sizeof(struct udphdr)) {
227 udpstat.udps_badlen++;
228 goto badunlocked;
229 }
230 m_adj(m, len - ip->ip_len);
231 /* ip->ip_len = len; */
232 }
233 /*
234 * Save a copy of the IP header in case we want restore it
235 * for sending an ICMP error message in response.
236 */
237 if (!blackhole)
238 save_ip = *ip;
239
240 /*
241 * Checksum extended UDP header and data.
242 */
243 if (uh->uh_sum) {
244 u_short uh_sum;
245 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
246 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
247 uh_sum = m->m_pkthdr.csum_data;
248 else
249 uh_sum = in_pseudo(ip->ip_src.s_addr,
250 ip->ip_dst.s_addr, htonl((u_short)len +
251 m->m_pkthdr.csum_data + IPPROTO_UDP));
252 uh_sum ^= 0xffff;
253 } else {
254 char b[9];
255 bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
256 bzero(((struct ipovly *)ip)->ih_x1, 9);
257 ((struct ipovly *)ip)->ih_len = uh->uh_ulen;
258 uh_sum = in_cksum(m, len + sizeof (struct ip));
259 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
260 }
261 if (uh_sum) {
262 udpstat.udps_badsum++;
263 m_freem(m);
264 return;
265 }
266 } else
267 udpstat.udps_nosum++;
268
269 #ifdef IPFIREWALL_FORWARD
270 /* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. */
271 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
272
273 if (fwd_tag != NULL) {
274 struct sockaddr_in *next_hop;
275
276 /* Do the hack. */
277 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
278 ip->ip_dst = next_hop->sin_addr;
279 uh->uh_dport = ntohs(next_hop->sin_port);
280 /* Remove the tag from the packet. We don't need it anymore. */
281 m_tag_delete(m, fwd_tag);
282 }
283 #endif
284
285 INP_INFO_RLOCK(&udbinfo);
286
287 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
288 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) {
289 struct inpcb *last;
290 /*
291 * Deliver a multicast or broadcast datagram to *all* sockets
292 * for which the local and remote addresses and ports match
293 * those of the incoming datagram. This allows more than
294 * one process to receive multi/broadcasts on the same port.
295 * (This really ought to be done for unicast datagrams as
296 * well, but that would cause problems with existing
297 * applications that open both address-specific sockets and
298 * a wildcard socket listening to the same port -- they would
299 * end up receiving duplicates of every unicast datagram.
300 * Those applications open the multiple sockets to overcome an
301 * inadequacy of the UDP socket interface, but for backwards
302 * compatibility we avoid the problem here rather than
303 * fixing the interface. Maybe 4.5BSD will remedy this?)
304 */
305
306 /*
307 * Locate pcb(s) for datagram.
308 * (Algorithm copied from raw_intr().)
309 */
310 last = NULL;
311 LIST_FOREACH(inp, &udb, inp_list) {
312 if (inp->inp_lport != uh->uh_dport)
313 continue;
314 #ifdef INET6
315 if ((inp->inp_vflag & INP_IPV4) == 0)
316 continue;
317 #endif
318 if (inp->inp_laddr.s_addr != INADDR_ANY) {
319 if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
320 continue;
321 }
322 if (inp->inp_faddr.s_addr != INADDR_ANY) {
323 if (inp->inp_faddr.s_addr !=
324 ip->ip_src.s_addr ||
325 inp->inp_fport != uh->uh_sport)
326 continue;
327 }
328 INP_LOCK(inp);
329
330 /*
331 * Check multicast packets to make sure they are only
332 * sent to sockets with multicast memberships for the
333 * packet's destination address and arrival interface
334 */
335 #define MSHIP(_inp, n) ((_inp)->inp_moptions->imo_membership[(n)])
336 #define NMSHIPS(_inp) ((_inp)->inp_moptions->imo_num_memberships)
337 if (strict_mcast_mship && inp->inp_moptions != NULL) {
338 int mship, foundmship = 0;
339
340 for (mship = 0; mship < NMSHIPS(inp); mship++) {
341 if (MSHIP(inp, mship)->inm_addr.s_addr
342 == ip->ip_dst.s_addr &&
343 MSHIP(inp, mship)->inm_ifp
344 == m->m_pkthdr.rcvif) {
345 foundmship = 1;
346 break;
347 }
348 }
349 if (foundmship == 0) {
350 INP_UNLOCK(inp);
351 continue;
352 }
353 }
354 #undef NMSHIPS
355 #undef MSHIP
356 if (last != NULL) {
357 struct mbuf *n;
358
359 n = m_copy(m, 0, M_COPYALL);
360 if (n != NULL)
361 udp_append(last, ip, n,
362 iphlen +
363 sizeof(struct udphdr),
364 &udp_in);
365 INP_UNLOCK(last);
366 }
367 last = inp;
368 /*
369 * Don't look for additional matches if this one does
370 * not have either the SO_REUSEPORT or SO_REUSEADDR
371 * socket options set. This heuristic avoids searching
372 * through all pcbs in the common case of a non-shared
373 * port. It * assumes that an application will never
374 * clear these options after setting them.
375 */
376 if ((last->inp_socket->so_options&(SO_REUSEPORT|SO_REUSEADDR)) == 0)
377 break;
378 }
379
380 if (last == NULL) {
381 /*
382 * No matching pcb found; discard datagram.
383 * (No need to send an ICMP Port Unreachable
384 * for a broadcast or multicast datgram.)
385 */
386 udpstat.udps_noportbcast++;
387 goto badheadlocked;
388 }
389 udp_append(last, ip, m, iphlen + sizeof(struct udphdr),
390 &udp_in);
391 INP_UNLOCK(last);
392 INP_INFO_RUNLOCK(&udbinfo);
393 return;
394 }
395 /*
396 * Locate pcb for datagram.
397 */
398 inp = in_pcblookup_hash(&udbinfo, ip->ip_src, uh->uh_sport,
399 ip->ip_dst, uh->uh_dport, 1, m->m_pkthdr.rcvif);
400 if (inp == NULL) {
401 if (log_in_vain) {
402 char buf[4*sizeof "123"];
403
404 strcpy(buf, inet_ntoa(ip->ip_dst));
405 log(LOG_INFO,
406 "Connection attempt to UDP %s:%d from %s:%d\n",
407 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src),
408 ntohs(uh->uh_sport));
409 }
410 udpstat.udps_noport++;
411 if (m->m_flags & (M_BCAST | M_MCAST)) {
412 udpstat.udps_noportbcast++;
413 goto badheadlocked;
414 }
415 if (blackhole)
416 goto badheadlocked;
417 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
418 goto badheadlocked;
419 *ip = save_ip;
420 ip->ip_len += iphlen;
421 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
422 INP_INFO_RUNLOCK(&udbinfo);
423 return;
424 }
425 INP_LOCK(inp);
426 /* Check the minimum TTL for socket. */
427 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl)
428 goto badheadlocked;
429 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in);
430 INP_UNLOCK(inp);
431 INP_INFO_RUNLOCK(&udbinfo);
432 return;
433
434 badheadlocked:
435 if (inp)
436 INP_UNLOCK(inp);
437 INP_INFO_RUNLOCK(&udbinfo);
438 badunlocked:
439 m_freem(m);
440 return;
441 }
442
443 /*
444 * Subroutine of udp_input(), which appends the provided mbuf chain to the
445 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that
446 * contains the source address. If the socket ends up being an IPv6 socket,
447 * udp_append() will convert to a sockaddr_in6 before passing the address
448 * into the socket code.
449 */
450 static void
451 udp_append(last, ip, n, off, udp_in)
452 struct inpcb *last;
453 struct ip *ip;
454 struct mbuf *n;
455 int off;
456 struct sockaddr_in *udp_in;
457 {
458 struct sockaddr *append_sa;
459 struct socket *so;
460 struct mbuf *opts = 0;
461 #ifdef INET6
462 struct sockaddr_in6 udp_in6;
463 #endif
464
465 INP_LOCK_ASSERT(last);
466
467 #if defined(IPSEC) || defined(FAST_IPSEC)
468 /* check AH/ESP integrity. */
469 if (ipsec4_in_reject(n, last)) {
470 #ifdef IPSEC
471 ipsecstat.in_polvio++;
472 #endif /*IPSEC*/
473 m_freem(n);
474 return;
475 }
476 #endif /*IPSEC || FAST_IPSEC*/
477 #ifdef MAC
478 if (mac_check_inpcb_deliver(last, n) != 0) {
479 m_freem(n);
480 return;
481 }
482 #endif
483 if (last->inp_flags & INP_CONTROLOPTS ||
484 last->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
485 #ifdef INET6
486 if (last->inp_vflag & INP_IPV6) {
487 int savedflags;
488
489 savedflags = last->inp_flags;
490 last->inp_flags &= ~INP_UNMAPPABLEOPTS;
491 ip6_savecontrol(last, n, &opts);
492 last->inp_flags = savedflags;
493 } else
494 #endif
495 ip_savecontrol(last, &opts, ip, n);
496 }
497 #ifdef INET6
498 if (last->inp_vflag & INP_IPV6) {
499 bzero(&udp_in6, sizeof(udp_in6));
500 udp_in6.sin6_len = sizeof(udp_in6);
501 udp_in6.sin6_family = AF_INET6;
502 in6_sin_2_v4mapsin6(udp_in, &udp_in6);
503 append_sa = (struct sockaddr *)&udp_in6;
504 } else
505 #endif
506 append_sa = (struct sockaddr *)udp_in;
507 m_adj(n, off);
508
509 so = last->inp_socket;
510 SOCKBUF_LOCK(&so->so_rcv);
511 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
512 m_freem(n);
513 if (opts)
514 m_freem(opts);
515 udpstat.udps_fullsock++;
516 SOCKBUF_UNLOCK(&so->so_rcv);
517 } else
518 sorwakeup_locked(so);
519 }
520
521 /*
522 * Notify a udp user of an asynchronous error;
523 * just wake up so that he can collect error status.
524 */
525 struct inpcb *
526 udp_notify(inp, errno)
527 register struct inpcb *inp;
528 int errno;
529 {
530 inp->inp_socket->so_error = errno;
531 sorwakeup(inp->inp_socket);
532 sowwakeup(inp->inp_socket);
533 return inp;
534 }
535
536 void
537 udp_ctlinput(cmd, sa, vip)
538 int cmd;
539 struct sockaddr *sa;
540 void *vip;
541 {
542 struct ip *ip = vip;
543 struct udphdr *uh;
544 struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
545 struct in_addr faddr;
546 struct inpcb *inp;
547
548 faddr = ((struct sockaddr_in *)sa)->sin_addr;
549 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
550 return;
551
552 /*
553 * Redirects don't need to be handled up here.
554 */
555 if (PRC_IS_REDIRECT(cmd))
556 return;
557 /*
558 * Hostdead is ugly because it goes linearly through all PCBs.
559 * XXX: We never get this from ICMP, otherwise it makes an
560 * excellent DoS attack on machines with many connections.
561 */
562 if (cmd == PRC_HOSTDEAD)
563 ip = 0;
564 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
565 return;
566 if (ip) {
567 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
568 INP_INFO_RLOCK(&udbinfo);
569 inp = in_pcblookup_hash(&udbinfo, faddr, uh->uh_dport,
570 ip->ip_src, uh->uh_sport, 0, NULL);
571 if (inp != NULL) {
572 INP_LOCK(inp);
573 if (inp->inp_socket != NULL) {
574 (*notify)(inp, inetctlerrmap[cmd]);
575 }
576 INP_UNLOCK(inp);
577 }
578 INP_INFO_RUNLOCK(&udbinfo);
579 } else
580 in_pcbnotifyall(&udbinfo, faddr, inetctlerrmap[cmd], notify);
581 }
582
583 static int
584 udp_pcblist(SYSCTL_HANDLER_ARGS)
585 {
586 int error, i, n;
587 struct inpcb *inp, **inp_list;
588 inp_gen_t gencnt;
589 struct xinpgen xig;
590
591 /*
592 * The process of preparing the TCB list is too time-consuming and
593 * resource-intensive to repeat twice on every request.
594 */
595 if (req->oldptr == 0) {
596 n = udbinfo.ipi_count;
597 req->oldidx = 2 * (sizeof xig)
598 + (n + n/8) * sizeof(struct xinpcb);
599 return 0;
600 }
601
602 if (req->newptr != 0)
603 return EPERM;
604
605 /*
606 * OK, now we're committed to doing something.
607 */
608 INP_INFO_RLOCK(&udbinfo);
609 gencnt = udbinfo.ipi_gencnt;
610 n = udbinfo.ipi_count;
611 INP_INFO_RUNLOCK(&udbinfo);
612
613 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
614 + n * sizeof(struct xinpcb));
615 if (error != 0)
616 return (error);
617
618 xig.xig_len = sizeof xig;
619 xig.xig_count = n;
620 xig.xig_gen = gencnt;
621 xig.xig_sogen = so_gencnt;
622 error = SYSCTL_OUT(req, &xig, sizeof xig);
623 if (error)
624 return error;
625
626 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
627 if (inp_list == 0)
628 return ENOMEM;
629
630 INP_INFO_RLOCK(&udbinfo);
631 for (inp = LIST_FIRST(udbinfo.listhead), i = 0; inp && i < n;
632 inp = LIST_NEXT(inp, inp_list)) {
633 INP_LOCK(inp);
634 if (inp->inp_gencnt <= gencnt &&
635 cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0)
636 inp_list[i++] = inp;
637 INP_UNLOCK(inp);
638 }
639 INP_INFO_RUNLOCK(&udbinfo);
640 n = i;
641
642 error = 0;
643 for (i = 0; i < n; i++) {
644 inp = inp_list[i];
645 INP_LOCK(inp);
646 if (inp->inp_gencnt <= gencnt) {
647 struct xinpcb xi;
648 bzero(&xi, sizeof(xi));
649 xi.xi_len = sizeof xi;
650 /* XXX should avoid extra copy */
651 bcopy(inp, &xi.xi_inp, sizeof *inp);
652 if (inp->inp_socket)
653 sotoxsocket(inp->inp_socket, &xi.xi_socket);
654 xi.xi_inp.inp_gencnt = inp->inp_gencnt;
655 INP_UNLOCK(inp);
656 error = SYSCTL_OUT(req, &xi, sizeof xi);
657 } else
658 INP_UNLOCK(inp);
659 }
660 if (!error) {
661 /*
662 * Give the user an updated idea of our state.
663 * If the generation differs from what we told
664 * her before, she knows that something happened
665 * while we were processing this request, and it
666 * might be necessary to retry.
667 */
668 INP_INFO_RLOCK(&udbinfo);
669 xig.xig_gen = udbinfo.ipi_gencnt;
670 xig.xig_sogen = so_gencnt;
671 xig.xig_count = udbinfo.ipi_count;
672 INP_INFO_RUNLOCK(&udbinfo);
673 error = SYSCTL_OUT(req, &xig, sizeof xig);
674 }
675 free(inp_list, M_TEMP);
676 return error;
677 }
678
679 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0,
680 udp_pcblist, "S,xinpcb", "List of active UDP sockets");
681
682 static int
683 udp_getcred(SYSCTL_HANDLER_ARGS)
684 {
685 struct xucred xuc;
686 struct sockaddr_in addrs[2];
687 struct inpcb *inp;
688 int error;
689
690 error = suser_cred(req->td->td_ucred, SUSER_ALLOWJAIL);
691 if (error)
692 return (error);
693 error = SYSCTL_IN(req, addrs, sizeof(addrs));
694 if (error)
695 return (error);
696 INP_INFO_RLOCK(&udbinfo);
697 inp = in_pcblookup_hash(&udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
698 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL);
699 if (inp == NULL || inp->inp_socket == NULL) {
700 error = ENOENT;
701 goto out;
702 }
703 error = cr_canseesocket(req->td->td_ucred, inp->inp_socket);
704 if (error)
705 goto out;
706 cru2x(inp->inp_socket->so_cred, &xuc);
707 out:
708 INP_INFO_RUNLOCK(&udbinfo);
709 if (error == 0)
710 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
711 return (error);
712 }
713
714 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
715 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
716 udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
717
718 static int
719 udp_output(inp, m, addr, control, td)
720 register struct inpcb *inp;
721 struct mbuf *m;
722 struct sockaddr *addr;
723 struct mbuf *control;
724 struct thread *td;
725 {
726 register struct udpiphdr *ui;
727 register int len = m->m_pkthdr.len;
728 struct in_addr faddr, laddr;
729 struct cmsghdr *cm;
730 struct sockaddr_in *sin, src;
731 int error = 0;
732 int ipflags;
733 u_short fport, lport;
734 int unlock_udbinfo;
735
736 /*
737 * udp_output() may need to temporarily bind or connect the current
738 * inpcb. As such, we don't know up front what inpcb locks we will
739 * need. Do any work to decide what is needed up front before
740 * acquiring locks.
741 */
742 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
743 if (control)
744 m_freem(control);
745 m_freem(m);
746 return EMSGSIZE;
747 }
748
749 src.sin_family = 0;
750 if (control != NULL) {
751 /*
752 * XXX: Currently, we assume all the optional information
753 * is stored in a single mbuf.
754 */
755 if (control->m_next) {
756 m_freem(control);
757 m_freem(m);
758 return EINVAL;
759 }
760 for (; control->m_len > 0;
761 control->m_data += CMSG_ALIGN(cm->cmsg_len),
762 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
763 cm = mtod(control, struct cmsghdr *);
764 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 ||
765 cm->cmsg_len > control->m_len) {
766 error = EINVAL;
767 break;
768 }
769 if (cm->cmsg_level != IPPROTO_IP)
770 continue;
771
772 switch (cm->cmsg_type) {
773 case IP_SENDSRCADDR:
774 if (cm->cmsg_len !=
775 CMSG_LEN(sizeof(struct in_addr))) {
776 error = EINVAL;
777 break;
778 }
779 bzero(&src, sizeof(src));
780 src.sin_family = AF_INET;
781 src.sin_len = sizeof(src);
782 src.sin_port = inp->inp_lport;
783 src.sin_addr = *(struct in_addr *)CMSG_DATA(cm);
784 break;
785 default:
786 error = ENOPROTOOPT;
787 break;
788 }
789 if (error)
790 break;
791 }
792 m_freem(control);
793 }
794 if (error) {
795 m_freem(m);
796 return error;
797 }
798
799 if (src.sin_family == AF_INET ||
800 addr != NULL) {
801 INP_INFO_WLOCK(&udbinfo);
802 unlock_udbinfo = 1;
803 } else
804 unlock_udbinfo = 0;
805 INP_LOCK(inp);
806
807 #ifdef MAC
808 mac_create_mbuf_from_inpcb(inp, m);
809 #endif
810
811 /*
812 * If the IP_SENDSRCADDR control message was specified, override the
813 * source address for this datagram. Its use is invalidated if the
814 * address thus specified is incomplete or clobbers other inpcbs.
815 */
816 laddr = inp->inp_laddr;
817 lport = inp->inp_lport;
818 if (src.sin_family == AF_INET) {
819 if ((lport == 0) ||
820 (laddr.s_addr == INADDR_ANY &&
821 src.sin_addr.s_addr == INADDR_ANY)) {
822 error = EINVAL;
823 goto release;
824 }
825 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
826 &laddr.s_addr, &lport, td->td_ucred);
827 if (error)
828 goto release;
829 }
830
831 if (addr) {
832 sin = (struct sockaddr_in *)addr;
833 if (jailed(td->td_ucred))
834 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr);
835 if (inp->inp_faddr.s_addr != INADDR_ANY) {
836 error = EISCONN;
837 goto release;
838 }
839 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, &lport,
840 &faddr.s_addr, &fport, NULL, td->td_ucred);
841 if (error)
842 goto release;
843
844 /* Commit the local port if newly assigned. */
845 if (inp->inp_laddr.s_addr == INADDR_ANY &&
846 inp->inp_lport == 0) {
847 /*
848 * Remember addr if jailed, to prevent rebinding.
849 */
850 if (jailed(td->td_ucred))
851 inp->inp_laddr = laddr;
852 inp->inp_lport = lport;
853 if (in_pcbinshash(inp) != 0) {
854 inp->inp_lport = 0;
855 error = EAGAIN;
856 goto release;
857 }
858 inp->inp_flags |= INP_ANONPORT;
859 }
860 } else {
861 faddr = inp->inp_faddr;
862 fport = inp->inp_fport;
863 if (faddr.s_addr == INADDR_ANY) {
864 error = ENOTCONN;
865 goto release;
866 }
867 }
868
869 /*
870 * Calculate data length and get a mbuf for UDP, IP, and possible
871 * link-layer headers. Immediate slide the data pointer back forward
872 * since we won't use that space at this layer.
873 */
874 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT);
875 if (m == NULL) {
876 error = ENOBUFS;
877 goto release;
878 }
879 m->m_data += max_linkhdr;
880 m->m_len -= max_linkhdr;
881 m->m_pkthdr.len -= max_linkhdr;
882
883 /*
884 * Fill in mbuf with extended UDP header
885 * and addresses and length put into network format.
886 */
887 ui = mtod(m, struct udpiphdr *);
888 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */
889 ui->ui_pr = IPPROTO_UDP;
890 ui->ui_src = laddr;
891 ui->ui_dst = faddr;
892 ui->ui_sport = lport;
893 ui->ui_dport = fport;
894 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
895
896 /*
897 * Set the Don't Fragment bit in the IP header.
898 */
899 if (inp->inp_flags & INP_DONTFRAG) {
900 struct ip *ip;
901 ip = (struct ip *)&ui->ui_i;
902 ip->ip_off |= IP_DF;
903 }
904
905 ipflags = 0;
906 if (inp->inp_socket->so_options & SO_DONTROUTE)
907 ipflags |= IP_ROUTETOIF;
908 if (inp->inp_socket->so_options & SO_BROADCAST)
909 ipflags |= IP_ALLOWBROADCAST;
910 if (inp->inp_flags & INP_ONESBCAST)
911 ipflags |= IP_SENDONES;
912
913 /*
914 * Set up checksum and output datagram.
915 */
916 if (udpcksum) {
917 if (inp->inp_flags & INP_ONESBCAST)
918 faddr.s_addr = INADDR_BROADCAST;
919 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
920 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP));
921 m->m_pkthdr.csum_flags = CSUM_UDP;
922 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
923 } else {
924 ui->ui_sum = 0;
925 }
926 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
927 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */
928 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */
929 udpstat.udps_opackets++;
930
931 if (unlock_udbinfo)
932 INP_INFO_WUNLOCK(&udbinfo);
933 error = ip_output(m, inp->inp_options, NULL, ipflags,
934 inp->inp_moptions, inp);
935 INP_UNLOCK(inp);
936 return (error);
937
938 release:
939 INP_UNLOCK(inp);
940 if (unlock_udbinfo)
941 INP_INFO_WUNLOCK(&udbinfo);
942 m_freem(m);
943 return (error);
944 }
945
946 u_long udp_sendspace = 9216; /* really max datagram size */
947 /* 40 1K datagrams */
948 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
949 &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
950
951 u_long udp_recvspace = 40 * (1024 +
952 #ifdef INET6
953 sizeof(struct sockaddr_in6)
954 #else
955 sizeof(struct sockaddr_in)
956 #endif
957 );
958 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
959 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
960
961 static int
962 udp_abort(struct socket *so)
963 {
964 struct inpcb *inp;
965
966 INP_INFO_WLOCK(&udbinfo);
967 inp = sotoinpcb(so);
968 if (inp == 0) {
969 INP_INFO_WUNLOCK(&udbinfo);
970 return EINVAL; /* ??? possible? panic instead? */
971 }
972 INP_LOCK(inp);
973 soisdisconnected(so);
974 in_pcbdetach(inp);
975 INP_INFO_WUNLOCK(&udbinfo);
976 return 0;
977 }
978
979 static int
980 udp_attach(struct socket *so, int proto, struct thread *td)
981 {
982 struct inpcb *inp;
983 int error;
984
985 INP_INFO_WLOCK(&udbinfo);
986 inp = sotoinpcb(so);
987 if (inp != 0) {
988 INP_INFO_WUNLOCK(&udbinfo);
989 return EINVAL;
990 }
991 error = soreserve(so, udp_sendspace, udp_recvspace);
992 if (error) {
993 INP_INFO_WUNLOCK(&udbinfo);
994 return error;
995 }
996 error = in_pcballoc(so, &udbinfo);
997 if (error) {
998 INP_INFO_WUNLOCK(&udbinfo);
999 return error;
1000 }
1001
1002 inp = (struct inpcb *)so->so_pcb;
1003 INP_INFO_WUNLOCK(&udbinfo);
1004 inp->inp_vflag |= INP_IPV4;
1005 inp->inp_ip_ttl = ip_defttl;
1006 INP_UNLOCK(inp);
1007 return 0;
1008 }
1009
1010 static int
1011 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1012 {
1013 struct inpcb *inp;
1014 int error;
1015
1016 INP_INFO_WLOCK(&udbinfo);
1017 inp = sotoinpcb(so);
1018 if (inp == 0) {
1019 INP_INFO_WUNLOCK(&udbinfo);
1020 return EINVAL;
1021 }
1022 INP_LOCK(inp);
1023 error = in_pcbbind(inp, nam, td->td_ucred);
1024 INP_UNLOCK(inp);
1025 INP_INFO_WUNLOCK(&udbinfo);
1026 return error;
1027 }
1028
1029 static int
1030 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1031 {
1032 struct inpcb *inp;
1033 int error;
1034 struct sockaddr_in *sin;
1035
1036 INP_INFO_WLOCK(&udbinfo);
1037 inp = sotoinpcb(so);
1038 if (inp == 0) {
1039 INP_INFO_WUNLOCK(&udbinfo);
1040 return EINVAL;
1041 }
1042 INP_LOCK(inp);
1043 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1044 INP_UNLOCK(inp);
1045 INP_INFO_WUNLOCK(&udbinfo);
1046 return EISCONN;
1047 }
1048 sin = (struct sockaddr_in *)nam;
1049 if (jailed(td->td_ucred))
1050 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr);
1051 error = in_pcbconnect(inp, nam, td->td_ucred);
1052 if (error == 0)
1053 soisconnected(so);
1054 INP_UNLOCK(inp);
1055 INP_INFO_WUNLOCK(&udbinfo);
1056 return error;
1057 }
1058
1059 static int
1060 udp_detach(struct socket *so)
1061 {
1062 struct inpcb *inp;
1063
1064 INP_INFO_WLOCK(&udbinfo);
1065 inp = sotoinpcb(so);
1066 if (inp == 0) {
1067 INP_INFO_WUNLOCK(&udbinfo);
1068 return EINVAL;
1069 }
1070 INP_LOCK(inp);
1071 in_pcbdetach(inp);
1072 INP_INFO_WUNLOCK(&udbinfo);
1073 return 0;
1074 }
1075
1076 static int
1077 udp_disconnect(struct socket *so)
1078 {
1079 struct inpcb *inp;
1080
1081 INP_INFO_WLOCK(&udbinfo);
1082 inp = sotoinpcb(so);
1083 if (inp == 0) {
1084 INP_INFO_WUNLOCK(&udbinfo);
1085 return EINVAL;
1086 }
1087 INP_LOCK(inp);
1088 if (inp->inp_faddr.s_addr == INADDR_ANY) {
1089 INP_INFO_WUNLOCK(&udbinfo);
1090 INP_UNLOCK(inp);
1091 return ENOTCONN;
1092 }
1093
1094 in_pcbdisconnect(inp);
1095 inp->inp_laddr.s_addr = INADDR_ANY;
1096 INP_UNLOCK(inp);
1097 INP_INFO_WUNLOCK(&udbinfo);
1098 so->so_state &= ~SS_ISCONNECTED; /* XXX */
1099 return 0;
1100 }
1101
1102 static int
1103 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1104 struct mbuf *control, struct thread *td)
1105 {
1106 struct inpcb *inp;
1107
1108 inp = sotoinpcb(so);
1109 return udp_output(inp, m, addr, control, td);
1110 }
1111
1112 int
1113 udp_shutdown(struct socket *so)
1114 {
1115 struct inpcb *inp;
1116
1117 INP_INFO_RLOCK(&udbinfo);
1118 inp = sotoinpcb(so);
1119 if (inp == 0) {
1120 INP_INFO_RUNLOCK(&udbinfo);
1121 return EINVAL;
1122 }
1123 INP_LOCK(inp);
1124 INP_INFO_RUNLOCK(&udbinfo);
1125 socantsendmore(so);
1126 INP_UNLOCK(inp);
1127 return 0;
1128 }
1129
1130 /*
1131 * This is the wrapper function for in_setsockaddr. We just pass down
1132 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking
1133 * here because in_setsockaddr will call malloc and might block.
1134 */
1135 static int
1136 udp_sockaddr(struct socket *so, struct sockaddr **nam)
1137 {
1138 return (in_setsockaddr(so, nam, &udbinfo));
1139 }
1140
1141 /*
1142 * This is the wrapper function for in_setpeeraddr. We just pass down
1143 * the pcbinfo for in_setpeeraddr to lock.
1144 */
1145 static int
1146 udp_peeraddr(struct socket *so, struct sockaddr **nam)
1147 {
1148 return (in_setpeeraddr(so, nam, &udbinfo));
1149 }
1150
1151 struct pr_usrreqs udp_usrreqs = {
1152 .pru_abort = udp_abort,
1153 .pru_attach = udp_attach,
1154 .pru_bind = udp_bind,
1155 .pru_connect = udp_connect,
1156 .pru_control = in_control,
1157 .pru_detach = udp_detach,
1158 .pru_disconnect = udp_disconnect,
1159 .pru_peeraddr = udp_peeraddr,
1160 .pru_send = udp_send,
1161 .pru_shutdown = udp_shutdown,
1162 .pru_sockaddr = udp_sockaddr,
1163 .pru_sosetlabel = in_pcbsosetlabel
1164 };
Cache object: 8740a26c0f9134a64b3193ac492c9929
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