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: releng/12.0/sys/netinet/ip_divert.c 340980 2018-11-26 16:36:38Z markj $");
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 #ifdef SCTP
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 #ifdef SCTP
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 bzero(&divsrc, sizeof(divsrc));
220 divsrc.sin_len = sizeof(divsrc);
221 divsrc.sin_family = AF_INET;
222 /* record matching rule, in host format */
223 divsrc.sin_port = ((struct ipfw_rule_ref *)(mtag+1))->rulenum;
224 /*
225 * Record receive interface address, if any.
226 * But only for incoming packets.
227 */
228 if (incoming) {
229 struct ifaddr *ifa;
230 struct ifnet *ifp;
231
232 /* Sanity check */
233 M_ASSERTPKTHDR(m);
234
235 /* Find IP address for receive interface */
236 ifp = m->m_pkthdr.rcvif;
237 if_addr_rlock(ifp);
238 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
239 if (ifa->ifa_addr->sa_family != AF_INET)
240 continue;
241 divsrc.sin_addr =
242 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr;
243 break;
244 }
245 if_addr_runlock(ifp);
246 }
247 /*
248 * Record the incoming interface name whenever we have one.
249 */
250 if (m->m_pkthdr.rcvif) {
251 /*
252 * Hide the actual interface name in there in the
253 * sin_zero array. XXX This needs to be moved to a
254 * different sockaddr type for divert, e.g.
255 * sockaddr_div with multiple fields like
256 * sockaddr_dl. Presently we have only 7 bytes
257 * but that will do for now as most interfaces
258 * are 4 or less + 2 or less bytes for unit.
259 * There is probably a faster way of doing this,
260 * possibly taking it from the sockaddr_dl on the iface.
261 * This solves the problem of a P2P link and a LAN interface
262 * having the same address, which can result in the wrong
263 * interface being assigned to the packet when fed back
264 * into the divert socket. Theoretically if the daemon saves
265 * and re-uses the sockaddr_in as suggested in the man pages,
266 * this iface name will come along for the ride.
267 * (see div_output for the other half of this.)
268 */
269 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname,
270 sizeof(divsrc.sin_zero));
271 }
272
273 /* Put packet on socket queue, if any */
274 sa = NULL;
275 nport = htons((u_int16_t)(((struct ipfw_rule_ref *)(mtag+1))->info));
276 INP_INFO_RLOCK_ET(&V_divcbinfo, et);
277 CK_LIST_FOREACH(inp, &V_divcb, inp_list) {
278 /* XXX why does only one socket match? */
279 if (inp->inp_lport == nport) {
280 INP_RLOCK(inp);
281 sa = inp->inp_socket;
282 SOCKBUF_LOCK(&sa->so_rcv);
283 if (sbappendaddr_locked(&sa->so_rcv,
284 (struct sockaddr *)&divsrc, m,
285 (struct mbuf *)0) == 0) {
286 SOCKBUF_UNLOCK(&sa->so_rcv);
287 sa = NULL; /* force mbuf reclaim below */
288 } else
289 sorwakeup_locked(sa);
290 INP_RUNLOCK(inp);
291 break;
292 }
293 }
294 INP_INFO_RUNLOCK_ET(&V_divcbinfo, et);
295 if (sa == NULL) {
296 m_freem(m);
297 KMOD_IPSTAT_INC(ips_noproto);
298 KMOD_IPSTAT_DEC(ips_delivered);
299 }
300 }
301
302 /*
303 * Deliver packet back into the IP processing machinery.
304 *
305 * If no address specified, or address is 0.0.0.0, send to ip_output();
306 * otherwise, send to ip_input() and mark as having been received on
307 * the interface with that address.
308 */
309 static int
310 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin,
311 struct mbuf *control)
312 {
313 struct ip *const ip = mtod(m, struct ip *);
314 struct m_tag *mtag;
315 struct ipfw_rule_ref *dt;
316 int error = 0;
317
318 /*
319 * An mbuf may hasn't come from userland, but we pretend
320 * that it has.
321 */
322 m->m_pkthdr.rcvif = NULL;
323 m->m_nextpkt = NULL;
324 M_SETFIB(m, so->so_fibnum);
325
326 if (control)
327 m_freem(control); /* XXX */
328
329 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
330 if (mtag == NULL) {
331 /* this should be normal */
332 mtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
333 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
334 if (mtag == NULL) {
335 error = ENOBUFS;
336 goto cantsend;
337 }
338 m_tag_prepend(m, mtag);
339 }
340 dt = (struct ipfw_rule_ref *)(mtag+1);
341
342 /* Loopback avoidance and state recovery */
343 if (sin) {
344 int i;
345
346 /* set the starting point. We provide a non-zero slot,
347 * but a non_matching chain_id to skip that info and use
348 * the rulenum/rule_id.
349 */
350 dt->slot = 1; /* dummy, chain_id is invalid */
351 dt->chain_id = 0;
352 dt->rulenum = sin->sin_port+1; /* host format ? */
353 dt->rule_id = 0;
354 /*
355 * Find receive interface with the given name, stuffed
356 * (if it exists) in the sin_zero[] field.
357 * The name is user supplied data so don't trust its size
358 * or that it is zero terminated.
359 */
360 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++)
361 ;
362 if ( i > 0 && i < sizeof(sin->sin_zero))
363 m->m_pkthdr.rcvif = ifunit(sin->sin_zero);
364 }
365
366 /* Reinject packet into the system as incoming or outgoing */
367 if (!sin || sin->sin_addr.s_addr == 0) {
368 struct mbuf *options = NULL;
369 struct inpcb *inp;
370
371 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_OUT;
372 inp = sotoinpcb(so);
373 INP_RLOCK(inp);
374 switch (ip->ip_v) {
375 case IPVERSION:
376 /*
377 * Don't allow both user specified and setsockopt
378 * options, and don't allow packet length sizes that
379 * will crash.
380 */
381 if ((((ip->ip_hl << 2) != sizeof(struct ip)) &&
382 inp->inp_options != NULL) ||
383 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) {
384 error = EINVAL;
385 INP_RUNLOCK(inp);
386 goto cantsend;
387 }
388 break;
389 #ifdef INET6
390 case IPV6_VERSION >> 4:
391 {
392 struct ip6_hdr *const ip6 = mtod(m, struct ip6_hdr *);
393
394 /* Don't allow packet length sizes that will crash */
395 if (((u_short)ntohs(ip6->ip6_plen) > m->m_pkthdr.len)) {
396 error = EINVAL;
397 INP_RUNLOCK(inp);
398 goto cantsend;
399 }
400 break;
401 }
402 #endif
403 default:
404 error = EINVAL;
405 INP_RUNLOCK(inp);
406 goto cantsend;
407 }
408
409 /* Send packet to output processing */
410 KMOD_IPSTAT_INC(ips_rawout); /* XXX */
411
412 #ifdef MAC
413 mac_inpcb_create_mbuf(inp, m);
414 #endif
415 /*
416 * Get ready to inject the packet into ip_output().
417 * Just in case socket options were specified on the
418 * divert socket, we duplicate them. This is done
419 * to avoid having to hold the PCB locks over the call
420 * to ip_output(), as doing this results in a number of
421 * lock ordering complexities.
422 *
423 * Note that we set the multicast options argument for
424 * ip_output() to NULL since it should be invariant that
425 * they are not present.
426 */
427 KASSERT(inp->inp_moptions == NULL,
428 ("multicast options set on a divert socket"));
429 /*
430 * XXXCSJP: It is unclear to me whether or not it makes
431 * sense for divert sockets to have options. However,
432 * for now we will duplicate them with the INP locks
433 * held so we can use them in ip_output() without
434 * requring a reference to the pcb.
435 */
436 if (inp->inp_options != NULL) {
437 options = m_dup(inp->inp_options, M_NOWAIT);
438 if (options == NULL) {
439 INP_RUNLOCK(inp);
440 error = ENOBUFS;
441 goto cantsend;
442 }
443 }
444 INP_RUNLOCK(inp);
445
446 switch (ip->ip_v) {
447 case IPVERSION:
448 error = ip_output(m, options, NULL,
449 ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0)
450 | IP_ALLOWBROADCAST | IP_RAWOUTPUT, NULL, NULL);
451 break;
452 #ifdef INET6
453 case IPV6_VERSION >> 4:
454 error = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
455 break;
456 #endif
457 }
458 if (options != NULL)
459 m_freem(options);
460 } else {
461 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_IN;
462 if (m->m_pkthdr.rcvif == NULL) {
463 /*
464 * No luck with the name, check by IP address.
465 * Clear the port and the ifname to make sure
466 * there are no distractions for ifa_ifwithaddr.
467 */
468 struct ifaddr *ifa;
469
470 bzero(sin->sin_zero, sizeof(sin->sin_zero));
471 sin->sin_port = 0;
472 NET_EPOCH_ENTER();
473 ifa = ifa_ifwithaddr((struct sockaddr *) sin);
474 if (ifa == NULL) {
475 error = EADDRNOTAVAIL;
476 NET_EPOCH_EXIT();
477 goto cantsend;
478 }
479 m->m_pkthdr.rcvif = ifa->ifa_ifp;
480 NET_EPOCH_EXIT();
481 }
482 #ifdef MAC
483 mac_socket_create_mbuf(so, m);
484 #endif
485 /* Send packet to input processing via netisr */
486 switch (ip->ip_v) {
487 case IPVERSION:
488 /*
489 * Restore M_BCAST flag when destination address is
490 * broadcast. It is expected by ip_tryforward().
491 */
492 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
493 m->m_flags |= M_MCAST;
494 else if (in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif))
495 m->m_flags |= M_BCAST;
496 netisr_queue_src(NETISR_IP, (uintptr_t)so, m);
497 break;
498 #ifdef INET6
499 case IPV6_VERSION >> 4:
500 netisr_queue_src(NETISR_IPV6, (uintptr_t)so, m);
501 break;
502 #endif
503 default:
504 error = EINVAL;
505 goto cantsend;
506 }
507 }
508
509 return (error);
510
511 cantsend:
512 m_freem(m);
513 return (error);
514 }
515
516 static int
517 div_attach(struct socket *so, int proto, struct thread *td)
518 {
519 struct inpcb *inp;
520 int error;
521
522 inp = sotoinpcb(so);
523 KASSERT(inp == NULL, ("div_attach: inp != NULL"));
524 if (td != NULL) {
525 error = priv_check(td, PRIV_NETINET_DIVERT);
526 if (error)
527 return (error);
528 }
529 error = soreserve(so, div_sendspace, div_recvspace);
530 if (error)
531 return error;
532 INP_INFO_WLOCK(&V_divcbinfo);
533 error = in_pcballoc(so, &V_divcbinfo);
534 if (error) {
535 INP_INFO_WUNLOCK(&V_divcbinfo);
536 return error;
537 }
538 inp = (struct inpcb *)so->so_pcb;
539 INP_INFO_WUNLOCK(&V_divcbinfo);
540 inp->inp_ip_p = proto;
541 inp->inp_vflag |= INP_IPV4;
542 inp->inp_flags |= INP_HDRINCL;
543 INP_WUNLOCK(inp);
544 return 0;
545 }
546
547 static void
548 div_detach(struct socket *so)
549 {
550 struct inpcb *inp;
551
552 inp = sotoinpcb(so);
553 KASSERT(inp != NULL, ("div_detach: inp == NULL"));
554 INP_INFO_WLOCK(&V_divcbinfo);
555 INP_WLOCK(inp);
556 in_pcbdetach(inp);
557 in_pcbfree(inp);
558 INP_INFO_WUNLOCK(&V_divcbinfo);
559 }
560
561 static int
562 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
563 {
564 struct inpcb *inp;
565 int error;
566
567 inp = sotoinpcb(so);
568 KASSERT(inp != NULL, ("div_bind: inp == NULL"));
569 /* in_pcbbind assumes that nam is a sockaddr_in
570 * and in_pcbbind requires a valid address. Since divert
571 * sockets don't we need to make sure the address is
572 * filled in properly.
573 * XXX -- divert should not be abusing in_pcbind
574 * and should probably have its own family.
575 */
576 if (nam->sa_family != AF_INET)
577 return EAFNOSUPPORT;
578 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY;
579 INP_INFO_WLOCK(&V_divcbinfo);
580 INP_WLOCK(inp);
581 INP_HASH_WLOCK(&V_divcbinfo);
582 error = in_pcbbind(inp, nam, td->td_ucred);
583 INP_HASH_WUNLOCK(&V_divcbinfo);
584 INP_WUNLOCK(inp);
585 INP_INFO_WUNLOCK(&V_divcbinfo);
586 return error;
587 }
588
589 static int
590 div_shutdown(struct socket *so)
591 {
592 struct inpcb *inp;
593
594 inp = sotoinpcb(so);
595 KASSERT(inp != NULL, ("div_shutdown: inp == NULL"));
596 INP_WLOCK(inp);
597 socantsendmore(so);
598 INP_WUNLOCK(inp);
599 return 0;
600 }
601
602 static int
603 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
604 struct mbuf *control, struct thread *td)
605 {
606
607 /* Packet must have a header (but that's about it) */
608 if (m->m_len < sizeof (struct ip) &&
609 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
610 KMOD_IPSTAT_INC(ips_toosmall);
611 m_freem(m);
612 return EINVAL;
613 }
614
615 /* Send packet */
616 return div_output(so, m, (struct sockaddr_in *)nam, control);
617 }
618
619 static void
620 div_ctlinput(int cmd, struct sockaddr *sa, void *vip)
621 {
622 struct in_addr faddr;
623
624 faddr = ((struct sockaddr_in *)sa)->sin_addr;
625 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
626 return;
627 if (PRC_IS_REDIRECT(cmd))
628 return;
629 }
630
631 static int
632 div_pcblist(SYSCTL_HANDLER_ARGS)
633 {
634 int error, i, n;
635 struct inpcb *inp, **inp_list;
636 inp_gen_t gencnt;
637 struct xinpgen xig;
638 struct epoch_tracker et;
639
640 /*
641 * The process of preparing the TCB list is too time-consuming and
642 * resource-intensive to repeat twice on every request.
643 */
644 if (req->oldptr == 0) {
645 n = V_divcbinfo.ipi_count;
646 n += imax(n / 8, 10);
647 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
648 return 0;
649 }
650
651 if (req->newptr != 0)
652 return EPERM;
653
654 /*
655 * OK, now we're committed to doing something.
656 */
657 INP_INFO_WLOCK(&V_divcbinfo);
658 gencnt = V_divcbinfo.ipi_gencnt;
659 n = V_divcbinfo.ipi_count;
660 INP_INFO_WUNLOCK(&V_divcbinfo);
661
662 error = sysctl_wire_old_buffer(req,
663 2 * sizeof(xig) + n*sizeof(struct xinpcb));
664 if (error != 0)
665 return (error);
666
667 bzero(&xig, sizeof(xig));
668 xig.xig_len = sizeof xig;
669 xig.xig_count = n;
670 xig.xig_gen = gencnt;
671 xig.xig_sogen = so_gencnt;
672 error = SYSCTL_OUT(req, &xig, sizeof xig);
673 if (error)
674 return error;
675
676 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
677 if (inp_list == NULL)
678 return ENOMEM;
679
680 INP_INFO_RLOCK_ET(&V_divcbinfo, et);
681 for (inp = CK_LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n;
682 inp = CK_LIST_NEXT(inp, inp_list)) {
683 INP_WLOCK(inp);
684 if (inp->inp_gencnt <= gencnt &&
685 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
686 in_pcbref(inp);
687 inp_list[i++] = inp;
688 }
689 INP_WUNLOCK(inp);
690 }
691 INP_INFO_RUNLOCK_ET(&V_divcbinfo, et);
692 n = i;
693
694 error = 0;
695 for (i = 0; i < n; i++) {
696 inp = inp_list[i];
697 INP_RLOCK(inp);
698 if (inp->inp_gencnt <= gencnt) {
699 struct xinpcb xi;
700
701 in_pcbtoxinpcb(inp, &xi);
702 INP_RUNLOCK(inp);
703 error = SYSCTL_OUT(req, &xi, sizeof xi);
704 } else
705 INP_RUNLOCK(inp);
706 }
707 INP_INFO_WLOCK(&V_divcbinfo);
708 for (i = 0; i < n; i++) {
709 inp = inp_list[i];
710 INP_RLOCK(inp);
711 if (!in_pcbrele_rlocked(inp))
712 INP_RUNLOCK(inp);
713 }
714 INP_INFO_WUNLOCK(&V_divcbinfo);
715
716 if (!error) {
717 struct epoch_tracker et;
718 /*
719 * Give the user an updated idea of our state.
720 * If the generation differs from what we told
721 * her before, she knows that something happened
722 * while we were processing this request, and it
723 * might be necessary to retry.
724 */
725 INP_INFO_RLOCK_ET(&V_divcbinfo, et);
726 xig.xig_gen = V_divcbinfo.ipi_gencnt;
727 xig.xig_sogen = so_gencnt;
728 xig.xig_count = V_divcbinfo.ipi_count;
729 INP_INFO_RUNLOCK_ET(&V_divcbinfo, et);
730 error = SYSCTL_OUT(req, &xig, sizeof xig);
731 }
732 free(inp_list, M_TEMP);
733 return error;
734 }
735
736 #ifdef SYSCTL_NODE
737 static SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0,
738 "IPDIVERT");
739 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD,
740 NULL, 0, div_pcblist, "S,xinpcb", "List of active divert sockets");
741 #endif
742
743 struct pr_usrreqs div_usrreqs = {
744 .pru_attach = div_attach,
745 .pru_bind = div_bind,
746 .pru_control = in_control,
747 .pru_detach = div_detach,
748 .pru_peeraddr = in_getpeeraddr,
749 .pru_send = div_send,
750 .pru_shutdown = div_shutdown,
751 .pru_sockaddr = in_getsockaddr,
752 .pru_sosetlabel = in_pcbsosetlabel
753 };
754
755 struct protosw div_protosw = {
756 .pr_type = SOCK_RAW,
757 .pr_protocol = IPPROTO_DIVERT,
758 .pr_flags = PR_ATOMIC|PR_ADDR,
759 .pr_input = div_input,
760 .pr_ctlinput = div_ctlinput,
761 .pr_ctloutput = ip_ctloutput,
762 .pr_init = div_init,
763 .pr_usrreqs = &div_usrreqs
764 };
765
766 static int
767 div_modevent(module_t mod, int type, void *unused)
768 {
769 int err = 0;
770
771 switch (type) {
772 case MOD_LOAD:
773 /*
774 * Protocol will be initialized by pf_proto_register().
775 * We don't have to register ip_protox because we are not
776 * a true IP protocol that goes over the wire.
777 */
778 err = pf_proto_register(PF_INET, &div_protosw);
779 if (err != 0)
780 return (err);
781 ip_divert_ptr = divert_packet;
782 ip_divert_event_tag = EVENTHANDLER_REGISTER(maxsockets_change,
783 div_zone_change, NULL, EVENTHANDLER_PRI_ANY);
784 break;
785 case MOD_QUIESCE:
786 /*
787 * IPDIVERT may normally not be unloaded because of the
788 * potential race conditions. Tell kldunload we can't be
789 * unloaded unless the unload is forced.
790 */
791 err = EPERM;
792 break;
793 case MOD_UNLOAD:
794 /*
795 * Forced unload.
796 *
797 * Module ipdivert can only be unloaded if no sockets are
798 * connected. Maybe this can be changed later to forcefully
799 * disconnect any open sockets.
800 *
801 * XXXRW: Note that there is a slight race here, as a new
802 * socket open request could be spinning on the lock and then
803 * we destroy the lock.
804 */
805 INP_INFO_WLOCK(&V_divcbinfo);
806 if (V_divcbinfo.ipi_count != 0) {
807 err = EBUSY;
808 INP_INFO_WUNLOCK(&V_divcbinfo);
809 break;
810 }
811 ip_divert_ptr = NULL;
812 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW);
813 INP_INFO_WUNLOCK(&V_divcbinfo);
814 #ifndef VIMAGE
815 div_destroy(NULL);
816 #endif
817 EVENTHANDLER_DEREGISTER(maxsockets_change, ip_divert_event_tag);
818 break;
819 default:
820 err = EOPNOTSUPP;
821 break;
822 }
823 return err;
824 }
825
826 static moduledata_t ipdivertmod = {
827 "ipdivert",
828 div_modevent,
829 0
830 };
831
832 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_FIREWALL, SI_ORDER_ANY);
833 MODULE_DEPEND(ipdivert, ipfw, 3, 3, 3);
834 MODULE_VERSION(ipdivert, 1);
Cache object: 008af032f7ebfd2145b4b0ed449a1725
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