1 /*-
2 * Copyright (c) 1982, 1986, 1988, 1993
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
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35 #include "opt_sctp.h"
36 #ifndef INET
37 #error "IPDIVERT requires INET"
38 #endif
39
40 #include <sys/param.h>
41 #include <sys/eventhandler.h>
42 #include <sys/kernel.h>
43 #include <sys/lock.h>
44 #include <sys/malloc.h>
45 #include <sys/mbuf.h>
46 #include <sys/module.h>
47 #include <sys/kernel.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/protosw.h>
51 #include <sys/socket.h>
52 #include <sys/socketvar.h>
53 #include <sys/sysctl.h>
54 #include <net/vnet.h>
55
56 #include <net/if.h>
57 #include <net/if_var.h>
58 #include <net/netisr.h>
59
60 #include <netinet/in.h>
61 #include <netinet/in_pcb.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/in_var.h>
64 #include <netinet/ip.h>
65 #include <netinet/ip_var.h>
66 #ifdef INET6
67 #include <netinet/ip6.h>
68 #include <netinet6/ip6_var.h>
69 #endif
70 #ifdef SCTP
71 #include <netinet/sctp_crc32.h>
72 #endif
73
74 #include <security/mac/mac_framework.h>
75
76 /*
77 * Divert sockets
78 */
79
80 /*
81 * Allocate enough space to hold a full IP packet
82 */
83 #define DIVSNDQ (65536 + 100)
84 #define DIVRCVQ (65536 + 100)
85
86 /*
87 * Divert sockets work in conjunction with ipfw or other packet filters,
88 * see the divert(4) manpage for features.
89 * Packets are selected by the packet filter and tagged with an
90 * MTAG_IPFW_RULE tag carrying the 'divert port' number (as set by
91 * the packet filter) and information on the matching filter rule for
92 * subsequent reinjection. The divert_port is used to put the packet
93 * on the corresponding divert socket, while the rule number is passed
94 * up (at least partially) as the sin_port in the struct sockaddr.
95 *
96 * Packets written to the divert socket carry in sin_addr a
97 * destination address, and in sin_port the number of the filter rule
98 * after which to continue processing.
99 * If the destination address is INADDR_ANY, the packet is treated as
100 * as outgoing and sent to ip_output(); otherwise it is treated as
101 * incoming and sent to ip_input().
102 * Further, sin_zero carries some information on the interface,
103 * which can be used in the reinject -- see comments in the code.
104 *
105 * On reinjection, processing in ip_input() and ip_output()
106 * will be exactly the same as for the original packet, except that
107 * packet filter processing will start at the rule number after the one
108 * written in the sin_port (ipfw does not allow a rule #0, so sin_port=0
109 * will apply the entire ruleset to the packet).
110 */
111
112 /* Internal variables. */
113 static VNET_DEFINE(struct inpcbhead, divcb);
114 static VNET_DEFINE(struct inpcbinfo, divcbinfo);
115
116 #define V_divcb VNET(divcb)
117 #define V_divcbinfo VNET(divcbinfo)
118
119 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */
120 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */
121
122 static eventhandler_tag ip_divert_event_tag;
123
124 /*
125 * Initialize divert connection block queue.
126 */
127 static void
128 div_zone_change(void *tag)
129 {
130
131 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets);
132 }
133
134 static int
135 div_inpcb_init(void *mem, int size, int flags)
136 {
137 struct inpcb *inp = mem;
138
139 INP_LOCK_INIT(inp, "inp", "divinp");
140 return (0);
141 }
142
143 static void
144 div_inpcb_fini(void *mem, int size)
145 {
146 struct inpcb *inp = mem;
147
148 INP_LOCK_DESTROY(inp);
149 }
150
151 static void
152 div_init(void)
153 {
154
155 /*
156 * XXX We don't use the hash list for divert IP, but it's easier to
157 * allocate one-entry hash lists than it is to check all over the
158 * place for hashbase == NULL.
159 */
160 in_pcbinfo_init(&V_divcbinfo, "div", &V_divcb, 1, 1, "divcb",
161 div_inpcb_init, div_inpcb_fini, 0, IPI_HASHFIELDS_NONE);
162 }
163
164 static void
165 div_destroy(void *unused __unused)
166 {
167
168 in_pcbinfo_destroy(&V_divcbinfo);
169 }
170 VNET_SYSUNINIT(divert, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
171 div_destroy, NULL);
172
173 /*
174 * IPPROTO_DIVERT is not in the real IP protocol number space; this
175 * function should never be called. Just in case, drop any packets.
176 */
177 static int
178 div_input(struct mbuf **mp, int *offp, int proto)
179 {
180 struct mbuf *m = *mp;
181
182 KMOD_IPSTAT_INC(ips_noproto);
183 m_freem(m);
184 return (IPPROTO_DONE);
185 }
186
187 /*
188 * Divert a packet by passing it up to the divert socket at port 'port'.
189 *
190 * Setup generic address and protocol structures for div_input routine,
191 * then pass them along with mbuf chain.
192 */
193 static void
194 divert_packet(struct mbuf *m, int incoming)
195 {
196 struct ip *ip;
197 struct inpcb *inp;
198 struct socket *sa;
199 u_int16_t nport;
200 struct sockaddr_in divsrc;
201 struct m_tag *mtag;
202
203 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
204 if (mtag == NULL) {
205 m_freem(m);
206 return;
207 }
208 /* Assure header */
209 if (m->m_len < sizeof(struct ip) &&
210 (m = m_pullup(m, sizeof(struct ip))) == NULL)
211 return;
212 ip = mtod(m, struct ip *);
213
214 /* Delayed checksums are currently not compatible with divert. */
215 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
216 in_delayed_cksum(m);
217 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
218 }
219 #ifdef SCTP
220 if (m->m_pkthdr.csum_flags & CSUM_SCTP) {
221 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
222 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
223 }
224 #endif
225 bzero(&divsrc, sizeof(divsrc));
226 divsrc.sin_len = sizeof(divsrc);
227 divsrc.sin_family = AF_INET;
228 /* record matching rule, in host format */
229 divsrc.sin_port = ((struct ipfw_rule_ref *)(mtag+1))->rulenum;
230 /*
231 * Record receive interface address, if any.
232 * But only for incoming packets.
233 */
234 if (incoming) {
235 struct ifaddr *ifa;
236 struct ifnet *ifp;
237
238 /* Sanity check */
239 M_ASSERTPKTHDR(m);
240
241 /* Find IP address for receive interface */
242 ifp = m->m_pkthdr.rcvif;
243 if_addr_rlock(ifp);
244 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
245 if (ifa->ifa_addr->sa_family != AF_INET)
246 continue;
247 divsrc.sin_addr =
248 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr;
249 break;
250 }
251 if_addr_runlock(ifp);
252 }
253 /*
254 * Record the incoming interface name whenever we have one.
255 */
256 if (m->m_pkthdr.rcvif) {
257 /*
258 * Hide the actual interface name in there in the
259 * sin_zero array. XXX This needs to be moved to a
260 * different sockaddr type for divert, e.g.
261 * sockaddr_div with multiple fields like
262 * sockaddr_dl. Presently we have only 7 bytes
263 * but that will do for now as most interfaces
264 * are 4 or less + 2 or less bytes for unit.
265 * There is probably a faster way of doing this,
266 * possibly taking it from the sockaddr_dl on the iface.
267 * This solves the problem of a P2P link and a LAN interface
268 * having the same address, which can result in the wrong
269 * interface being assigned to the packet when fed back
270 * into the divert socket. Theoretically if the daemon saves
271 * and re-uses the sockaddr_in as suggested in the man pages,
272 * this iface name will come along for the ride.
273 * (see div_output for the other half of this.)
274 */
275 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname,
276 sizeof(divsrc.sin_zero));
277 }
278
279 /* Put packet on socket queue, if any */
280 sa = NULL;
281 nport = htons((u_int16_t)(((struct ipfw_rule_ref *)(mtag+1))->info));
282 INP_INFO_RLOCK(&V_divcbinfo);
283 LIST_FOREACH(inp, &V_divcb, inp_list) {
284 /* XXX why does only one socket match? */
285 if (inp->inp_lport == nport) {
286 INP_RLOCK(inp);
287 sa = inp->inp_socket;
288 SOCKBUF_LOCK(&sa->so_rcv);
289 if (sbappendaddr_locked(&sa->so_rcv,
290 (struct sockaddr *)&divsrc, m,
291 (struct mbuf *)0) == 0) {
292 SOCKBUF_UNLOCK(&sa->so_rcv);
293 sa = NULL; /* force mbuf reclaim below */
294 } else
295 sorwakeup_locked(sa);
296 INP_RUNLOCK(inp);
297 break;
298 }
299 }
300 INP_INFO_RUNLOCK(&V_divcbinfo);
301 if (sa == NULL) {
302 m_freem(m);
303 KMOD_IPSTAT_INC(ips_noproto);
304 KMOD_IPSTAT_DEC(ips_delivered);
305 }
306 }
307
308 /*
309 * Deliver packet back into the IP processing machinery.
310 *
311 * If no address specified, or address is 0.0.0.0, send to ip_output();
312 * otherwise, send to ip_input() and mark as having been received on
313 * the interface with that address.
314 */
315 static int
316 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin,
317 struct mbuf *control)
318 {
319 struct ip *const ip = mtod(m, struct ip *);
320 struct m_tag *mtag;
321 struct ipfw_rule_ref *dt;
322 int error = 0;
323
324 /*
325 * An mbuf may hasn't come from userland, but we pretend
326 * that it has.
327 */
328 m->m_pkthdr.rcvif = NULL;
329 m->m_nextpkt = NULL;
330 M_SETFIB(m, so->so_fibnum);
331
332 if (control)
333 m_freem(control); /* XXX */
334
335 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
336 if (mtag == NULL) {
337 /* this should be normal */
338 mtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
339 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
340 if (mtag == NULL) {
341 error = ENOBUFS;
342 goto cantsend;
343 }
344 m_tag_prepend(m, mtag);
345 }
346 dt = (struct ipfw_rule_ref *)(mtag+1);
347
348 /* Loopback avoidance and state recovery */
349 if (sin) {
350 int i;
351
352 /* set the starting point. We provide a non-zero slot,
353 * but a non_matching chain_id to skip that info and use
354 * the rulenum/rule_id.
355 */
356 dt->slot = 1; /* dummy, chain_id is invalid */
357 dt->chain_id = 0;
358 dt->rulenum = sin->sin_port+1; /* host format ? */
359 dt->rule_id = 0;
360 /*
361 * Find receive interface with the given name, stuffed
362 * (if it exists) in the sin_zero[] field.
363 * The name is user supplied data so don't trust its size
364 * or that it is zero terminated.
365 */
366 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++)
367 ;
368 if ( i > 0 && i < sizeof(sin->sin_zero))
369 m->m_pkthdr.rcvif = ifunit(sin->sin_zero);
370 }
371
372 /* Reinject packet into the system as incoming or outgoing */
373 if (!sin || sin->sin_addr.s_addr == 0) {
374 struct mbuf *options = NULL;
375 struct inpcb *inp;
376
377 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_OUT;
378 inp = sotoinpcb(so);
379 INP_RLOCK(inp);
380 switch (ip->ip_v) {
381 case IPVERSION:
382 /*
383 * Don't allow both user specified and setsockopt
384 * options, and don't allow packet length sizes that
385 * will crash.
386 */
387 if ((((ip->ip_hl << 2) != sizeof(struct ip)) &&
388 inp->inp_options != NULL) ||
389 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) {
390 error = EINVAL;
391 INP_RUNLOCK(inp);
392 goto cantsend;
393 }
394 break;
395 #ifdef INET6
396 case IPV6_VERSION >> 4:
397 {
398 struct ip6_hdr *const ip6 = mtod(m, struct ip6_hdr *);
399
400 /* Don't allow packet length sizes that will crash */
401 if (((u_short)ntohs(ip6->ip6_plen) > m->m_pkthdr.len)) {
402 error = EINVAL;
403 INP_RUNLOCK(inp);
404 goto cantsend;
405 }
406 break;
407 }
408 #endif
409 default:
410 error = EINVAL;
411 INP_RUNLOCK(inp);
412 goto cantsend;
413 }
414
415 /* Send packet to output processing */
416 KMOD_IPSTAT_INC(ips_rawout); /* XXX */
417
418 #ifdef MAC
419 mac_inpcb_create_mbuf(inp, m);
420 #endif
421 /*
422 * Get ready to inject the packet into ip_output().
423 * Just in case socket options were specified on the
424 * divert socket, we duplicate them. This is done
425 * to avoid having to hold the PCB locks over the call
426 * to ip_output(), as doing this results in a number of
427 * lock ordering complexities.
428 *
429 * Note that we set the multicast options argument for
430 * ip_output() to NULL since it should be invariant that
431 * they are not present.
432 */
433 KASSERT(inp->inp_moptions == NULL,
434 ("multicast options set on a divert socket"));
435 /*
436 * XXXCSJP: It is unclear to me whether or not it makes
437 * sense for divert sockets to have options. However,
438 * for now we will duplicate them with the INP locks
439 * held so we can use them in ip_output() without
440 * requring a reference to the pcb.
441 */
442 if (inp->inp_options != NULL) {
443 options = m_dup(inp->inp_options, M_NOWAIT);
444 if (options == NULL) {
445 INP_RUNLOCK(inp);
446 error = ENOBUFS;
447 goto cantsend;
448 }
449 }
450 INP_RUNLOCK(inp);
451
452 switch (ip->ip_v) {
453 case IPVERSION:
454 error = ip_output(m, options, NULL,
455 ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0)
456 | IP_ALLOWBROADCAST | IP_RAWOUTPUT, NULL, NULL);
457 break;
458 #ifdef INET6
459 case IPV6_VERSION >> 4:
460 error = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
461 break;
462 #endif
463 }
464 if (options != NULL)
465 m_freem(options);
466 } else {
467 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_IN;
468 if (m->m_pkthdr.rcvif == NULL) {
469 /*
470 * No luck with the name, check by IP address.
471 * Clear the port and the ifname to make sure
472 * there are no distractions for ifa_ifwithaddr.
473 */
474 struct ifaddr *ifa;
475
476 bzero(sin->sin_zero, sizeof(sin->sin_zero));
477 sin->sin_port = 0;
478 ifa = ifa_ifwithaddr((struct sockaddr *) sin);
479 if (ifa == NULL) {
480 error = EADDRNOTAVAIL;
481 goto cantsend;
482 }
483 m->m_pkthdr.rcvif = ifa->ifa_ifp;
484 ifa_free(ifa);
485 }
486 #ifdef MAC
487 mac_socket_create_mbuf(so, m);
488 #endif
489 /* Send packet to input processing via netisr */
490 switch (ip->ip_v) {
491 case IPVERSION:
492 /*
493 * Restore M_BCAST flag when destination address is
494 * broadcast. It is expected by ip_tryforward().
495 */
496 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
497 m->m_flags |= M_MCAST;
498 else if (in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif))
499 m->m_flags |= M_BCAST;
500 netisr_queue_src(NETISR_IP, (uintptr_t)so, m);
501 break;
502 #ifdef INET6
503 case IPV6_VERSION >> 4:
504 netisr_queue_src(NETISR_IPV6, (uintptr_t)so, m);
505 break;
506 #endif
507 default:
508 error = EINVAL;
509 goto cantsend;
510 }
511 }
512
513 return (error);
514
515 cantsend:
516 m_freem(m);
517 return (error);
518 }
519
520 static int
521 div_attach(struct socket *so, int proto, struct thread *td)
522 {
523 struct inpcb *inp;
524 int error;
525
526 inp = sotoinpcb(so);
527 KASSERT(inp == NULL, ("div_attach: inp != NULL"));
528 if (td != NULL) {
529 error = priv_check(td, PRIV_NETINET_DIVERT);
530 if (error)
531 return (error);
532 }
533 error = soreserve(so, div_sendspace, div_recvspace);
534 if (error)
535 return error;
536 INP_INFO_WLOCK(&V_divcbinfo);
537 error = in_pcballoc(so, &V_divcbinfo);
538 if (error) {
539 INP_INFO_WUNLOCK(&V_divcbinfo);
540 return error;
541 }
542 inp = (struct inpcb *)so->so_pcb;
543 INP_INFO_WUNLOCK(&V_divcbinfo);
544 inp->inp_ip_p = proto;
545 inp->inp_vflag |= INP_IPV4;
546 inp->inp_flags |= INP_HDRINCL;
547 INP_WUNLOCK(inp);
548 return 0;
549 }
550
551 static void
552 div_detach(struct socket *so)
553 {
554 struct inpcb *inp;
555
556 inp = sotoinpcb(so);
557 KASSERT(inp != NULL, ("div_detach: inp == NULL"));
558 INP_INFO_WLOCK(&V_divcbinfo);
559 INP_WLOCK(inp);
560 in_pcbdetach(inp);
561 in_pcbfree(inp);
562 INP_INFO_WUNLOCK(&V_divcbinfo);
563 }
564
565 static int
566 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
567 {
568 struct inpcb *inp;
569 int error;
570
571 inp = sotoinpcb(so);
572 KASSERT(inp != NULL, ("div_bind: inp == NULL"));
573 /* in_pcbbind assumes that nam is a sockaddr_in
574 * and in_pcbbind requires a valid address. Since divert
575 * sockets don't we need to make sure the address is
576 * filled in properly.
577 * XXX -- divert should not be abusing in_pcbind
578 * and should probably have its own family.
579 */
580 if (nam->sa_family != AF_INET)
581 return EAFNOSUPPORT;
582 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY;
583 INP_INFO_WLOCK(&V_divcbinfo);
584 INP_WLOCK(inp);
585 INP_HASH_WLOCK(&V_divcbinfo);
586 error = in_pcbbind(inp, nam, td->td_ucred);
587 INP_HASH_WUNLOCK(&V_divcbinfo);
588 INP_WUNLOCK(inp);
589 INP_INFO_WUNLOCK(&V_divcbinfo);
590 return error;
591 }
592
593 static int
594 div_shutdown(struct socket *so)
595 {
596 struct inpcb *inp;
597
598 inp = sotoinpcb(so);
599 KASSERT(inp != NULL, ("div_shutdown: inp == NULL"));
600 INP_WLOCK(inp);
601 socantsendmore(so);
602 INP_WUNLOCK(inp);
603 return 0;
604 }
605
606 static int
607 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
608 struct mbuf *control, struct thread *td)
609 {
610
611 /* Packet must have a header (but that's about it) */
612 if (m->m_len < sizeof (struct ip) &&
613 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
614 KMOD_IPSTAT_INC(ips_toosmall);
615 m_freem(m);
616 return EINVAL;
617 }
618
619 /* Send packet */
620 return div_output(so, m, (struct sockaddr_in *)nam, control);
621 }
622
623 static void
624 div_ctlinput(int cmd, struct sockaddr *sa, void *vip)
625 {
626 struct in_addr faddr;
627
628 faddr = ((struct sockaddr_in *)sa)->sin_addr;
629 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
630 return;
631 if (PRC_IS_REDIRECT(cmd))
632 return;
633 }
634
635 static int
636 div_pcblist(SYSCTL_HANDLER_ARGS)
637 {
638 int error, i, n;
639 struct inpcb *inp, **inp_list;
640 inp_gen_t gencnt;
641 struct xinpgen xig;
642
643 /*
644 * The process of preparing the TCB list is too time-consuming and
645 * resource-intensive to repeat twice on every request.
646 */
647 if (req->oldptr == 0) {
648 n = V_divcbinfo.ipi_count;
649 n += imax(n / 8, 10);
650 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
651 return 0;
652 }
653
654 if (req->newptr != 0)
655 return EPERM;
656
657 /*
658 * OK, now we're committed to doing something.
659 */
660 INP_INFO_RLOCK(&V_divcbinfo);
661 gencnt = V_divcbinfo.ipi_gencnt;
662 n = V_divcbinfo.ipi_count;
663 INP_INFO_RUNLOCK(&V_divcbinfo);
664
665 error = sysctl_wire_old_buffer(req,
666 2 * sizeof(xig) + n*sizeof(struct xinpcb));
667 if (error != 0)
668 return (error);
669
670 bzero(&xig, sizeof(xig));
671 xig.xig_len = sizeof xig;
672 xig.xig_count = n;
673 xig.xig_gen = gencnt;
674 xig.xig_sogen = so_gencnt;
675 error = SYSCTL_OUT(req, &xig, sizeof xig);
676 if (error)
677 return error;
678
679 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
680 if (inp_list == NULL)
681 return ENOMEM;
682
683 INP_INFO_RLOCK(&V_divcbinfo);
684 for (inp = LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n;
685 inp = LIST_NEXT(inp, inp_list)) {
686 INP_WLOCK(inp);
687 if (inp->inp_gencnt <= gencnt &&
688 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
689 in_pcbref(inp);
690 inp_list[i++] = inp;
691 }
692 INP_WUNLOCK(inp);
693 }
694 INP_INFO_RUNLOCK(&V_divcbinfo);
695 n = i;
696
697 error = 0;
698 for (i = 0; i < n; i++) {
699 inp = inp_list[i];
700 INP_RLOCK(inp);
701 if (inp->inp_gencnt <= gencnt) {
702 struct xinpcb xi;
703 bzero(&xi, sizeof(xi));
704 xi.xi_len = sizeof xi;
705 /* XXX should avoid extra copy */
706 bcopy(inp, &xi.xi_inp, sizeof *inp);
707 if (inp->inp_socket)
708 sotoxsocket(inp->inp_socket, &xi.xi_socket);
709 INP_RUNLOCK(inp);
710 error = SYSCTL_OUT(req, &xi, sizeof xi);
711 } else
712 INP_RUNLOCK(inp);
713 }
714 INP_INFO_WLOCK(&V_divcbinfo);
715 for (i = 0; i < n; i++) {
716 inp = inp_list[i];
717 INP_RLOCK(inp);
718 if (!in_pcbrele_rlocked(inp))
719 INP_RUNLOCK(inp);
720 }
721 INP_INFO_WUNLOCK(&V_divcbinfo);
722
723 if (!error) {
724 /*
725 * Give the user an updated idea of our state.
726 * If the generation differs from what we told
727 * her before, she knows that something happened
728 * while we were processing this request, and it
729 * might be necessary to retry.
730 */
731 INP_INFO_RLOCK(&V_divcbinfo);
732 xig.xig_gen = V_divcbinfo.ipi_gencnt;
733 xig.xig_sogen = so_gencnt;
734 xig.xig_count = V_divcbinfo.ipi_count;
735 INP_INFO_RUNLOCK(&V_divcbinfo);
736 error = SYSCTL_OUT(req, &xig, sizeof xig);
737 }
738 free(inp_list, M_TEMP);
739 return error;
740 }
741
742 #ifdef SYSCTL_NODE
743 static SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0,
744 "IPDIVERT");
745 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD,
746 NULL, 0, div_pcblist, "S,xinpcb", "List of active divert sockets");
747 #endif
748
749 struct pr_usrreqs div_usrreqs = {
750 .pru_attach = div_attach,
751 .pru_bind = div_bind,
752 .pru_control = in_control,
753 .pru_detach = div_detach,
754 .pru_peeraddr = in_getpeeraddr,
755 .pru_send = div_send,
756 .pru_shutdown = div_shutdown,
757 .pru_sockaddr = in_getsockaddr,
758 .pru_sosetlabel = in_pcbsosetlabel
759 };
760
761 struct protosw div_protosw = {
762 .pr_type = SOCK_RAW,
763 .pr_protocol = IPPROTO_DIVERT,
764 .pr_flags = PR_ATOMIC|PR_ADDR,
765 .pr_input = div_input,
766 .pr_ctlinput = div_ctlinput,
767 .pr_ctloutput = ip_ctloutput,
768 .pr_init = div_init,
769 .pr_usrreqs = &div_usrreqs
770 };
771
772 static int
773 div_modevent(module_t mod, int type, void *unused)
774 {
775 int err = 0;
776
777 switch (type) {
778 case MOD_LOAD:
779 /*
780 * Protocol will be initialized by pf_proto_register().
781 * We don't have to register ip_protox because we are not
782 * a true IP protocol that goes over the wire.
783 */
784 err = pf_proto_register(PF_INET, &div_protosw);
785 if (err != 0)
786 return (err);
787 ip_divert_ptr = divert_packet;
788 ip_divert_event_tag = EVENTHANDLER_REGISTER(maxsockets_change,
789 div_zone_change, NULL, EVENTHANDLER_PRI_ANY);
790 break;
791 case MOD_QUIESCE:
792 /*
793 * IPDIVERT may normally not be unloaded because of the
794 * potential race conditions. Tell kldunload we can't be
795 * unloaded unless the unload is forced.
796 */
797 err = EPERM;
798 break;
799 case MOD_UNLOAD:
800 /*
801 * Forced unload.
802 *
803 * Module ipdivert can only be unloaded if no sockets are
804 * connected. Maybe this can be changed later to forcefully
805 * disconnect any open sockets.
806 *
807 * XXXRW: Note that there is a slight race here, as a new
808 * socket open request could be spinning on the lock and then
809 * we destroy the lock.
810 */
811 INP_INFO_WLOCK(&V_divcbinfo);
812 if (V_divcbinfo.ipi_count != 0) {
813 err = EBUSY;
814 INP_INFO_WUNLOCK(&V_divcbinfo);
815 break;
816 }
817 ip_divert_ptr = NULL;
818 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW);
819 INP_INFO_WUNLOCK(&V_divcbinfo);
820 #ifndef VIMAGE
821 div_destroy(NULL);
822 #endif
823 EVENTHANDLER_DEREGISTER(maxsockets_change, ip_divert_event_tag);
824 break;
825 default:
826 err = EOPNOTSUPP;
827 break;
828 }
829 return err;
830 }
831
832 static moduledata_t ipdivertmod = {
833 "ipdivert",
834 div_modevent,
835 0
836 };
837
838 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_FIREWALL, SI_ORDER_ANY);
839 MODULE_DEPEND(ipdivert, ipfw, 3, 3, 3);
840 MODULE_VERSION(ipdivert, 1);
Cache object: 46dfc6b388db6eae550c7f7cdc52d972
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