1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 #include "opt_sctp.h"
38 #ifndef INET
39 #error "IPDIVERT requires INET"
40 #endif
41
42 #include <sys/param.h>
43 #include <sys/eventhandler.h>
44 #include <sys/kernel.h>
45 #include <sys/lock.h>
46 #include <sys/malloc.h>
47 #include <sys/mbuf.h>
48 #include <sys/module.h>
49 #include <sys/kernel.h>
50 #include <sys/priv.h>
51 #include <sys/proc.h>
52 #include <sys/protosw.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55 #include <sys/sysctl.h>
56 #include <net/vnet.h>
57
58 #include <net/if.h>
59 #include <net/if_var.h>
60 #include <net/netisr.h>
61
62 #include <netinet/in.h>
63 #include <netinet/in_pcb.h>
64 #include <netinet/in_systm.h>
65 #include <netinet/in_var.h>
66 #include <netinet/ip.h>
67 #include <netinet/ip_var.h>
68 #ifdef INET6
69 #include <netinet/ip6.h>
70 #include <netinet6/ip6_var.h>
71 #endif
72 #if defined(SCTP) || defined(SCTP_SUPPORT)
73 #include <netinet/sctp_crc32.h>
74 #endif
75
76 #include <security/mac/mac_framework.h>
77 /*
78 * Divert sockets
79 */
80
81 /*
82 * Allocate enough space to hold a full IP packet
83 */
84 #define DIVSNDQ (65536 + 100)
85 #define DIVRCVQ (65536 + 100)
86
87 /*
88 * Divert sockets work in conjunction with ipfw or other packet filters,
89 * see the divert(4) manpage for features.
90 * Packets are selected by the packet filter and tagged with an
91 * MTAG_IPFW_RULE tag carrying the 'divert port' number (as set by
92 * the packet filter) and information on the matching filter rule for
93 * subsequent reinjection. The divert_port is used to put the packet
94 * on the corresponding divert socket, while the rule number is passed
95 * up (at least partially) as the sin_port in the struct sockaddr.
96 *
97 * Packets written to the divert socket carry in sin_addr a
98 * destination address, and in sin_port the number of the filter rule
99 * after which to continue processing.
100 * If the destination address is INADDR_ANY, the packet is treated as
101 * as outgoing and sent to ip_output(); otherwise it is treated as
102 * incoming and sent to ip_input().
103 * Further, sin_zero carries some information on the interface,
104 * which can be used in the reinject -- see comments in the code.
105 *
106 * On reinjection, processing in ip_input() and ip_output()
107 * will be exactly the same as for the original packet, except that
108 * packet filter processing will start at the rule number after the one
109 * written in the sin_port (ipfw does not allow a rule #0, so sin_port=0
110 * will apply the entire ruleset to the packet).
111 */
112
113 /* Internal variables. */
114 VNET_DEFINE_STATIC(struct inpcbhead, divcb);
115 VNET_DEFINE_STATIC(struct inpcbinfo, divcbinfo);
116
117 #define V_divcb VNET(divcb)
118 #define V_divcbinfo VNET(divcbinfo)
119
120 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */
121 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */
122
123 static eventhandler_tag ip_divert_event_tag;
124
125 /*
126 * Initialize divert connection block queue.
127 */
128 static void
129 div_zone_change(void *tag)
130 {
131
132 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets);
133 }
134
135 static int
136 div_inpcb_init(void *mem, int size, int flags)
137 {
138 struct inpcb *inp = mem;
139
140 INP_LOCK_INIT(inp, "inp", "divinp");
141 return (0);
142 }
143
144 static void
145 div_init(void)
146 {
147
148 /*
149 * XXX We don't use the hash list for divert IP, but it's easier to
150 * allocate one-entry hash lists than it is to check all over the
151 * place for hashbase == NULL.
152 */
153 in_pcbinfo_init(&V_divcbinfo, "div", &V_divcb, 1, 1, "divcb",
154 div_inpcb_init, IPI_HASHFIELDS_NONE);
155 }
156
157 static void
158 div_destroy(void *unused __unused)
159 {
160
161 in_pcbinfo_destroy(&V_divcbinfo);
162 }
163 VNET_SYSUNINIT(divert, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
164 div_destroy, NULL);
165
166 /*
167 * IPPROTO_DIVERT is not in the real IP protocol number space; this
168 * function should never be called. Just in case, drop any packets.
169 */
170 static int
171 div_input(struct mbuf **mp, int *offp, int proto)
172 {
173 struct mbuf *m = *mp;
174
175 KMOD_IPSTAT_INC(ips_noproto);
176 m_freem(m);
177 return (IPPROTO_DONE);
178 }
179
180 /*
181 * Divert a packet by passing it up to the divert socket at port 'port'.
182 *
183 * Setup generic address and protocol structures for div_input routine,
184 * then pass them along with mbuf chain.
185 */
186 static void
187 divert_packet(struct mbuf *m, int incoming)
188 {
189 struct ip *ip;
190 struct inpcb *inp;
191 struct socket *sa;
192 u_int16_t nport;
193 struct sockaddr_in divsrc;
194 struct m_tag *mtag;
195 struct epoch_tracker et;
196
197 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
198 if (mtag == NULL) {
199 m_freem(m);
200 return;
201 }
202 /* Assure header */
203 if (m->m_len < sizeof(struct ip) &&
204 (m = m_pullup(m, sizeof(struct ip))) == NULL)
205 return;
206 ip = mtod(m, struct ip *);
207
208 /* Delayed checksums are currently not compatible with divert. */
209 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
210 in_delayed_cksum(m);
211 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
212 }
213 #if defined(SCTP) || defined(SCTP_SUPPORT)
214 if (m->m_pkthdr.csum_flags & CSUM_SCTP) {
215 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
216 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
217 }
218 #endif
219 #ifdef INET6
220 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
221 in6_delayed_cksum(m, m->m_pkthdr.len -
222 sizeof(struct ip6_hdr), sizeof(struct ip6_hdr));
223 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
224 }
225 #if defined(SCTP) || defined(SCTP_SUPPORT)
226 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
227 sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
228 m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
229 }
230 #endif
231 #endif /* INET6 */
232 bzero(&divsrc, sizeof(divsrc));
233 divsrc.sin_len = sizeof(divsrc);
234 divsrc.sin_family = AF_INET;
235 /* record matching rule, in host format */
236 divsrc.sin_port = ((struct ipfw_rule_ref *)(mtag+1))->rulenum;
237 /*
238 * Record receive interface address, if any.
239 * But only for incoming packets.
240 */
241 if (incoming) {
242 struct ifaddr *ifa;
243 struct ifnet *ifp;
244
245 /* Sanity check */
246 M_ASSERTPKTHDR(m);
247
248 /* Find IP address for receive interface */
249 ifp = m->m_pkthdr.rcvif;
250 if_addr_rlock(ifp);
251 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
252 if (ifa->ifa_addr->sa_family != AF_INET)
253 continue;
254 divsrc.sin_addr =
255 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr;
256 break;
257 }
258 if_addr_runlock(ifp);
259 }
260 /*
261 * Record the incoming interface name whenever we have one.
262 */
263 if (m->m_pkthdr.rcvif) {
264 /*
265 * Hide the actual interface name in there in the
266 * sin_zero array. XXX This needs to be moved to a
267 * different sockaddr type for divert, e.g.
268 * sockaddr_div with multiple fields like
269 * sockaddr_dl. Presently we have only 7 bytes
270 * but that will do for now as most interfaces
271 * are 4 or less + 2 or less bytes for unit.
272 * There is probably a faster way of doing this,
273 * possibly taking it from the sockaddr_dl on the iface.
274 * This solves the problem of a P2P link and a LAN interface
275 * having the same address, which can result in the wrong
276 * interface being assigned to the packet when fed back
277 * into the divert socket. Theoretically if the daemon saves
278 * and re-uses the sockaddr_in as suggested in the man pages,
279 * this iface name will come along for the ride.
280 * (see div_output for the other half of this.)
281 */
282 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname,
283 sizeof(divsrc.sin_zero));
284 }
285
286 /* Put packet on socket queue, if any */
287 sa = NULL;
288 nport = htons((u_int16_t)(((struct ipfw_rule_ref *)(mtag+1))->info));
289 INP_INFO_RLOCK_ET(&V_divcbinfo, et);
290 CK_LIST_FOREACH(inp, &V_divcb, inp_list) {
291 /* XXX why does only one socket match? */
292 if (inp->inp_lport == nport) {
293 INP_RLOCK(inp);
294 if (__predict_false(inp->inp_flags2 & INP_FREED)) {
295 INP_RUNLOCK(inp);
296 continue;
297 }
298 sa = inp->inp_socket;
299 SOCKBUF_LOCK(&sa->so_rcv);
300 if (sbappendaddr_locked(&sa->so_rcv,
301 (struct sockaddr *)&divsrc, m,
302 (struct mbuf *)0) == 0) {
303 soroverflow_locked(sa);
304 sa = NULL; /* force mbuf reclaim below */
305 } else
306 sorwakeup_locked(sa);
307 INP_RUNLOCK(inp);
308 break;
309 }
310 }
311 INP_INFO_RUNLOCK_ET(&V_divcbinfo, et);
312 if (sa == NULL) {
313 m_freem(m);
314 KMOD_IPSTAT_INC(ips_noproto);
315 KMOD_IPSTAT_DEC(ips_delivered);
316 }
317 }
318
319 /*
320 * Deliver packet back into the IP processing machinery.
321 *
322 * If no address specified, or address is 0.0.0.0, send to ip_output();
323 * otherwise, send to ip_input() and mark as having been received on
324 * the interface with that address.
325 */
326 static int
327 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin,
328 struct mbuf *control)
329 {
330 struct ip *const ip = mtod(m, struct ip *);
331 struct m_tag *mtag;
332 struct ipfw_rule_ref *dt;
333 int error = 0;
334
335 /*
336 * An mbuf may hasn't come from userland, but we pretend
337 * that it has.
338 */
339 m->m_pkthdr.rcvif = NULL;
340 m->m_nextpkt = NULL;
341 M_SETFIB(m, so->so_fibnum);
342
343 if (control)
344 m_freem(control); /* XXX */
345
346 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
347 if (mtag == NULL) {
348 /* this should be normal */
349 mtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
350 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
351 if (mtag == NULL) {
352 error = ENOBUFS;
353 goto cantsend;
354 }
355 m_tag_prepend(m, mtag);
356 }
357 dt = (struct ipfw_rule_ref *)(mtag+1);
358
359 /* Loopback avoidance and state recovery */
360 if (sin) {
361 int i;
362
363 /* set the starting point. We provide a non-zero slot,
364 * but a non_matching chain_id to skip that info and use
365 * the rulenum/rule_id.
366 */
367 dt->slot = 1; /* dummy, chain_id is invalid */
368 dt->chain_id = 0;
369 dt->rulenum = sin->sin_port+1; /* host format ? */
370 dt->rule_id = 0;
371 /*
372 * Find receive interface with the given name, stuffed
373 * (if it exists) in the sin_zero[] field.
374 * The name is user supplied data so don't trust its size
375 * or that it is zero terminated.
376 */
377 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++)
378 ;
379 if ( i > 0 && i < sizeof(sin->sin_zero))
380 m->m_pkthdr.rcvif = ifunit(sin->sin_zero);
381 }
382
383 /* Reinject packet into the system as incoming or outgoing */
384 if (!sin || sin->sin_addr.s_addr == 0) {
385 struct mbuf *options = NULL;
386 struct inpcb *inp;
387
388 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_OUT;
389 inp = sotoinpcb(so);
390 INP_RLOCK(inp);
391 switch (ip->ip_v) {
392 case IPVERSION:
393 /*
394 * Don't allow both user specified and setsockopt
395 * options, and don't allow packet length sizes that
396 * will crash.
397 */
398 if ((((ip->ip_hl << 2) != sizeof(struct ip)) &&
399 inp->inp_options != NULL) ||
400 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) {
401 error = EINVAL;
402 INP_RUNLOCK(inp);
403 goto cantsend;
404 }
405 break;
406 #ifdef INET6
407 case IPV6_VERSION >> 4:
408 {
409 struct ip6_hdr *const ip6 = mtod(m, struct ip6_hdr *);
410
411 /* Don't allow packet length sizes that will crash */
412 if (((u_short)ntohs(ip6->ip6_plen) > m->m_pkthdr.len)) {
413 error = EINVAL;
414 INP_RUNLOCK(inp);
415 goto cantsend;
416 }
417 break;
418 }
419 #endif
420 default:
421 error = EINVAL;
422 INP_RUNLOCK(inp);
423 goto cantsend;
424 }
425
426 /* Send packet to output processing */
427 KMOD_IPSTAT_INC(ips_rawout); /* XXX */
428
429 #ifdef MAC
430 mac_inpcb_create_mbuf(inp, m);
431 #endif
432 /*
433 * Get ready to inject the packet into ip_output().
434 * Just in case socket options were specified on the
435 * divert socket, we duplicate them. This is done
436 * to avoid having to hold the PCB locks over the call
437 * to ip_output(), as doing this results in a number of
438 * lock ordering complexities.
439 *
440 * Note that we set the multicast options argument for
441 * ip_output() to NULL since it should be invariant that
442 * they are not present.
443 */
444 KASSERT(inp->inp_moptions == NULL,
445 ("multicast options set on a divert socket"));
446 /*
447 * XXXCSJP: It is unclear to me whether or not it makes
448 * sense for divert sockets to have options. However,
449 * for now we will duplicate them with the INP locks
450 * held so we can use them in ip_output() without
451 * requring a reference to the pcb.
452 */
453 if (inp->inp_options != NULL) {
454 options = m_dup(inp->inp_options, M_NOWAIT);
455 if (options == NULL) {
456 INP_RUNLOCK(inp);
457 error = ENOBUFS;
458 goto cantsend;
459 }
460 }
461 INP_RUNLOCK(inp);
462
463 switch (ip->ip_v) {
464 case IPVERSION:
465 error = ip_output(m, options, NULL,
466 ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0)
467 | IP_ALLOWBROADCAST | IP_RAWOUTPUT, NULL, NULL);
468 break;
469 #ifdef INET6
470 case IPV6_VERSION >> 4:
471 error = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
472 break;
473 #endif
474 }
475 if (options != NULL)
476 m_freem(options);
477 } else {
478 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_IN;
479 if (m->m_pkthdr.rcvif == NULL) {
480 /*
481 * No luck with the name, check by IP address.
482 * Clear the port and the ifname to make sure
483 * there are no distractions for ifa_ifwithaddr.
484 */
485 struct ifaddr *ifa;
486
487 bzero(sin->sin_zero, sizeof(sin->sin_zero));
488 sin->sin_port = 0;
489 NET_EPOCH_ENTER();
490 ifa = ifa_ifwithaddr((struct sockaddr *) sin);
491 if (ifa == NULL) {
492 error = EADDRNOTAVAIL;
493 NET_EPOCH_EXIT();
494 goto cantsend;
495 }
496 m->m_pkthdr.rcvif = ifa->ifa_ifp;
497 NET_EPOCH_EXIT();
498 }
499 #ifdef MAC
500 mac_socket_create_mbuf(so, m);
501 #endif
502 /* Send packet to input processing via netisr */
503 switch (ip->ip_v) {
504 case IPVERSION:
505 /*
506 * Restore M_BCAST flag when destination address is
507 * broadcast. It is expected by ip_tryforward().
508 */
509 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
510 m->m_flags |= M_MCAST;
511 else if (in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif))
512 m->m_flags |= M_BCAST;
513 netisr_queue_src(NETISR_IP, (uintptr_t)so, m);
514 break;
515 #ifdef INET6
516 case IPV6_VERSION >> 4:
517 netisr_queue_src(NETISR_IPV6, (uintptr_t)so, m);
518 break;
519 #endif
520 default:
521 error = EINVAL;
522 goto cantsend;
523 }
524 }
525
526 return (error);
527
528 cantsend:
529 m_freem(m);
530 return (error);
531 }
532
533 static int
534 div_attach(struct socket *so, int proto, struct thread *td)
535 {
536 struct inpcb *inp;
537 int error;
538
539 inp = sotoinpcb(so);
540 KASSERT(inp == NULL, ("div_attach: inp != NULL"));
541 if (td != NULL) {
542 error = priv_check(td, PRIV_NETINET_DIVERT);
543 if (error)
544 return (error);
545 }
546 error = soreserve(so, div_sendspace, div_recvspace);
547 if (error)
548 return error;
549 INP_INFO_WLOCK(&V_divcbinfo);
550 error = in_pcballoc(so, &V_divcbinfo);
551 if (error) {
552 INP_INFO_WUNLOCK(&V_divcbinfo);
553 return error;
554 }
555 inp = (struct inpcb *)so->so_pcb;
556 INP_INFO_WUNLOCK(&V_divcbinfo);
557 inp->inp_ip_p = proto;
558 inp->inp_vflag |= INP_IPV4;
559 inp->inp_flags |= INP_HDRINCL;
560 INP_WUNLOCK(inp);
561 return 0;
562 }
563
564 static void
565 div_detach(struct socket *so)
566 {
567 struct inpcb *inp;
568
569 inp = sotoinpcb(so);
570 KASSERT(inp != NULL, ("div_detach: inp == NULL"));
571 INP_INFO_WLOCK(&V_divcbinfo);
572 INP_WLOCK(inp);
573 in_pcbdetach(inp);
574 in_pcbfree(inp);
575 INP_INFO_WUNLOCK(&V_divcbinfo);
576 }
577
578 static int
579 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
580 {
581 struct inpcb *inp;
582 int error;
583
584 inp = sotoinpcb(so);
585 KASSERT(inp != NULL, ("div_bind: inp == NULL"));
586 /* in_pcbbind assumes that nam is a sockaddr_in
587 * and in_pcbbind requires a valid address. Since divert
588 * sockets don't we need to make sure the address is
589 * filled in properly.
590 * XXX -- divert should not be abusing in_pcbind
591 * and should probably have its own family.
592 */
593 if (nam->sa_family != AF_INET)
594 return EAFNOSUPPORT;
595 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY;
596 INP_INFO_WLOCK(&V_divcbinfo);
597 INP_WLOCK(inp);
598 INP_HASH_WLOCK(&V_divcbinfo);
599 error = in_pcbbind(inp, nam, td->td_ucred);
600 INP_HASH_WUNLOCK(&V_divcbinfo);
601 INP_WUNLOCK(inp);
602 INP_INFO_WUNLOCK(&V_divcbinfo);
603 return error;
604 }
605
606 static int
607 div_shutdown(struct socket *so)
608 {
609 struct inpcb *inp;
610
611 inp = sotoinpcb(so);
612 KASSERT(inp != NULL, ("div_shutdown: inp == NULL"));
613 INP_WLOCK(inp);
614 socantsendmore(so);
615 INP_WUNLOCK(inp);
616 return 0;
617 }
618
619 static int
620 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
621 struct mbuf *control, struct thread *td)
622 {
623
624 /* Packet must have a header (but that's about it) */
625 if (m->m_len < sizeof (struct ip) &&
626 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
627 KMOD_IPSTAT_INC(ips_toosmall);
628 m_freem(m);
629 return EINVAL;
630 }
631
632 /* Send packet */
633 return div_output(so, m, (struct sockaddr_in *)nam, control);
634 }
635
636 static void
637 div_ctlinput(int cmd, struct sockaddr *sa, void *vip)
638 {
639 struct in_addr faddr;
640
641 faddr = ((struct sockaddr_in *)sa)->sin_addr;
642 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
643 return;
644 if (PRC_IS_REDIRECT(cmd))
645 return;
646 }
647
648 static int
649 div_pcblist(SYSCTL_HANDLER_ARGS)
650 {
651 int error, i, n;
652 struct inpcb *inp, **inp_list;
653 inp_gen_t gencnt;
654 struct xinpgen xig;
655 struct epoch_tracker et;
656
657 /*
658 * The process of preparing the TCB list is too time-consuming and
659 * resource-intensive to repeat twice on every request.
660 */
661 if (req->oldptr == 0) {
662 n = V_divcbinfo.ipi_count;
663 n += imax(n / 8, 10);
664 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
665 return 0;
666 }
667
668 if (req->newptr != 0)
669 return EPERM;
670
671 /*
672 * OK, now we're committed to doing something.
673 */
674 INP_INFO_WLOCK(&V_divcbinfo);
675 gencnt = V_divcbinfo.ipi_gencnt;
676 n = V_divcbinfo.ipi_count;
677 INP_INFO_WUNLOCK(&V_divcbinfo);
678
679 error = sysctl_wire_old_buffer(req,
680 2 * sizeof(xig) + n*sizeof(struct xinpcb));
681 if (error != 0)
682 return (error);
683
684 bzero(&xig, sizeof(xig));
685 xig.xig_len = sizeof xig;
686 xig.xig_count = n;
687 xig.xig_gen = gencnt;
688 xig.xig_sogen = so_gencnt;
689 error = SYSCTL_OUT(req, &xig, sizeof xig);
690 if (error)
691 return error;
692
693 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
694 if (inp_list == NULL)
695 return ENOMEM;
696
697 INP_INFO_RLOCK_ET(&V_divcbinfo, et);
698 for (inp = CK_LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n;
699 inp = CK_LIST_NEXT(inp, inp_list)) {
700 INP_WLOCK(inp);
701 if (inp->inp_gencnt <= gencnt &&
702 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
703 in_pcbref(inp);
704 inp_list[i++] = inp;
705 }
706 INP_WUNLOCK(inp);
707 }
708 INP_INFO_RUNLOCK_ET(&V_divcbinfo, et);
709 n = i;
710
711 error = 0;
712 for (i = 0; i < n; i++) {
713 inp = inp_list[i];
714 INP_RLOCK(inp);
715 if (inp->inp_gencnt <= gencnt) {
716 struct xinpcb xi;
717
718 in_pcbtoxinpcb(inp, &xi);
719 INP_RUNLOCK(inp);
720 error = SYSCTL_OUT(req, &xi, sizeof xi);
721 } else
722 INP_RUNLOCK(inp);
723 }
724 INP_INFO_WLOCK(&V_divcbinfo);
725 for (i = 0; i < n; i++) {
726 inp = inp_list[i];
727 INP_RLOCK(inp);
728 if (!in_pcbrele_rlocked(inp))
729 INP_RUNLOCK(inp);
730 }
731 INP_INFO_WUNLOCK(&V_divcbinfo);
732
733 if (!error) {
734 struct epoch_tracker et;
735 /*
736 * Give the user an updated idea of our state.
737 * If the generation differs from what we told
738 * her before, she knows that something happened
739 * while we were processing this request, and it
740 * might be necessary to retry.
741 */
742 INP_INFO_RLOCK_ET(&V_divcbinfo, et);
743 xig.xig_gen = V_divcbinfo.ipi_gencnt;
744 xig.xig_sogen = so_gencnt;
745 xig.xig_count = V_divcbinfo.ipi_count;
746 INP_INFO_RUNLOCK_ET(&V_divcbinfo, et);
747 error = SYSCTL_OUT(req, &xig, sizeof xig);
748 }
749 free(inp_list, M_TEMP);
750 return error;
751 }
752
753 #ifdef SYSCTL_NODE
754 static SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0,
755 "IPDIVERT");
756 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD,
757 NULL, 0, div_pcblist, "S,xinpcb", "List of active divert sockets");
758 #endif
759
760 struct pr_usrreqs div_usrreqs = {
761 .pru_attach = div_attach,
762 .pru_bind = div_bind,
763 .pru_control = in_control,
764 .pru_detach = div_detach,
765 .pru_peeraddr = in_getpeeraddr,
766 .pru_send = div_send,
767 .pru_shutdown = div_shutdown,
768 .pru_sockaddr = in_getsockaddr,
769 .pru_sosetlabel = in_pcbsosetlabel
770 };
771
772 struct protosw div_protosw = {
773 .pr_type = SOCK_RAW,
774 .pr_protocol = IPPROTO_DIVERT,
775 .pr_flags = PR_ATOMIC|PR_ADDR,
776 .pr_input = div_input,
777 .pr_ctlinput = div_ctlinput,
778 .pr_ctloutput = ip_ctloutput,
779 .pr_init = div_init,
780 .pr_usrreqs = &div_usrreqs
781 };
782
783 static int
784 div_modevent(module_t mod, int type, void *unused)
785 {
786 int err = 0;
787
788 switch (type) {
789 case MOD_LOAD:
790 /*
791 * Protocol will be initialized by pf_proto_register().
792 * We don't have to register ip_protox because we are not
793 * a true IP protocol that goes over the wire.
794 */
795 err = pf_proto_register(PF_INET, &div_protosw);
796 if (err != 0)
797 return (err);
798 ip_divert_ptr = divert_packet;
799 ip_divert_event_tag = EVENTHANDLER_REGISTER(maxsockets_change,
800 div_zone_change, NULL, EVENTHANDLER_PRI_ANY);
801 break;
802 case MOD_QUIESCE:
803 /*
804 * IPDIVERT may normally not be unloaded because of the
805 * potential race conditions. Tell kldunload we can't be
806 * unloaded unless the unload is forced.
807 */
808 err = EPERM;
809 break;
810 case MOD_UNLOAD:
811 /*
812 * Forced unload.
813 *
814 * Module ipdivert can only be unloaded if no sockets are
815 * connected. Maybe this can be changed later to forcefully
816 * disconnect any open sockets.
817 *
818 * XXXRW: Note that there is a slight race here, as a new
819 * socket open request could be spinning on the lock and then
820 * we destroy the lock.
821 */
822 INP_INFO_WLOCK(&V_divcbinfo);
823 if (V_divcbinfo.ipi_count != 0) {
824 err = EBUSY;
825 INP_INFO_WUNLOCK(&V_divcbinfo);
826 break;
827 }
828 ip_divert_ptr = NULL;
829 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW);
830 INP_INFO_WUNLOCK(&V_divcbinfo);
831 #ifndef VIMAGE
832 div_destroy(NULL);
833 #endif
834 EVENTHANDLER_DEREGISTER(maxsockets_change, ip_divert_event_tag);
835 break;
836 default:
837 err = EOPNOTSUPP;
838 break;
839 }
840 return err;
841 }
842
843 static moduledata_t ipdivertmod = {
844 "ipdivert",
845 div_modevent,
846 0
847 };
848
849 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_FIREWALL, SI_ORDER_ANY);
850 MODULE_DEPEND(ipdivert, ipfw, 3, 3, 3);
851 MODULE_VERSION(ipdivert, 1);
Cache object: ba299cb09204541a8b99abf29f134bb6
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