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/kernel.h>
42 #include <sys/lock.h>
43 #include <sys/malloc.h>
44 #include <sys/mbuf.h>
45 #include <sys/module.h>
46 #include <sys/kernel.h>
47 #include <sys/priv.h>
48 #include <sys/proc.h>
49 #include <sys/protosw.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/sysctl.h>
53 #include <net/vnet.h>
54
55 #include <net/if.h>
56 #include <net/netisr.h>
57
58 #include <netinet/in.h>
59 #include <netinet/in_pcb.h>
60 #include <netinet/in_systm.h>
61 #include <netinet/in_var.h>
62 #include <netinet/ip.h>
63 #include <netinet/ip_var.h>
64 #ifdef INET6
65 #include <netinet/ip6.h>
66 #include <netinet6/ip6_var.h>
67 #endif
68 #ifdef SCTP
69 #include <netinet/sctp_crc32.h>
70 #endif
71
72 #include <security/mac/mac_framework.h>
73
74 /*
75 * Divert sockets
76 */
77
78 /*
79 * Allocate enough space to hold a full IP packet
80 */
81 #define DIVSNDQ (65536 + 100)
82 #define DIVRCVQ (65536 + 100)
83
84 /*
85 * Divert sockets work in conjunction with ipfw or other packet filters,
86 * see the divert(4) manpage for features.
87 * Packets are selected by the packet filter and tagged with an
88 * MTAG_IPFW_RULE tag carrying the 'divert port' number (as set by
89 * the packet filter) and information on the matching filter rule for
90 * subsequent reinjection. The divert_port is used to put the packet
91 * on the corresponding divert socket, while the rule number is passed
92 * up (at least partially) as the sin_port in the struct sockaddr.
93 *
94 * Packets written to the divert socket carry in sin_addr a
95 * destination address, and in sin_port the number of the filter rule
96 * after which to continue processing.
97 * If the destination address is INADDR_ANY, the packet is treated as
98 * as outgoing and sent to ip_output(); otherwise it is treated as
99 * incoming and sent to ip_input().
100 * Further, sin_zero carries some information on the interface,
101 * which can be used in the reinject -- see comments in the code.
102 *
103 * On reinjection, processing in ip_input() and ip_output()
104 * will be exactly the same as for the original packet, except that
105 * packet filter processing will start at the rule number after the one
106 * written in the sin_port (ipfw does not allow a rule #0, so sin_port=0
107 * will apply the entire ruleset to the packet).
108 */
109
110 /* Internal variables. */
111 static VNET_DEFINE(struct inpcbhead, divcb);
112 static VNET_DEFINE(struct inpcbinfo, divcbinfo);
113
114 #define V_divcb VNET(divcb)
115 #define V_divcbinfo VNET(divcbinfo)
116
117 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */
118 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */
119
120 static eventhandler_tag ip_divert_event_tag;
121
122 /*
123 * Initialize divert connection block queue.
124 */
125 static void
126 div_zone_change(void *tag)
127 {
128
129 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets);
130 }
131
132 static int
133 div_inpcb_init(void *mem, int size, int flags)
134 {
135 struct inpcb *inp = mem;
136
137 INP_LOCK_INIT(inp, "inp", "divinp");
138 return (0);
139 }
140
141 static void
142 div_inpcb_fini(void *mem, int size)
143 {
144 struct inpcb *inp = mem;
145
146 INP_LOCK_DESTROY(inp);
147 }
148
149 static void
150 div_init(void)
151 {
152
153 /*
154 * XXX We don't use the hash list for divert IP, but it's easier to
155 * allocate one-entry hash lists than it is to check all over the
156 * place for hashbase == NULL.
157 */
158 in_pcbinfo_init(&V_divcbinfo, "div", &V_divcb, 1, 1, "divcb",
159 div_inpcb_init, div_inpcb_fini, UMA_ZONE_NOFREE,
160 IPI_HASHFIELDS_NONE);
161 }
162
163 static void
164 div_destroy(void)
165 {
166
167 in_pcbinfo_destroy(&V_divcbinfo);
168 }
169
170 /*
171 * IPPROTO_DIVERT is not in the real IP protocol number space; this
172 * function should never be called. Just in case, drop any packets.
173 */
174 static void
175 div_input(struct mbuf *m, int off)
176 {
177
178 KMOD_IPSTAT_INC(ips_noproto);
179 m_freem(m);
180 }
181
182 /*
183 * Divert a packet by passing it up to the divert socket at port 'port'.
184 *
185 * Setup generic address and protocol structures for div_input routine,
186 * then pass them along with mbuf chain.
187 */
188 static void
189 divert_packet(struct mbuf *m, int incoming)
190 {
191 struct ip *ip;
192 struct inpcb *inp;
193 struct socket *sa;
194 u_int16_t nport;
195 struct sockaddr_in divsrc;
196 struct m_tag *mtag;
197
198 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
199 if (mtag == NULL) {
200 m_freem(m);
201 return;
202 }
203 /* Assure header */
204 if (m->m_len < sizeof(struct ip) &&
205 (m = m_pullup(m, sizeof(struct ip))) == 0)
206 return;
207 ip = mtod(m, struct ip *);
208
209 /* Delayed checksums are currently not compatible with divert. */
210 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
211 in_delayed_cksum(m);
212 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
213 }
214 #ifdef SCTP
215 if (m->m_pkthdr.csum_flags & CSUM_SCTP) {
216 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
217 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
218 }
219 #endif
220 bzero(&divsrc, sizeof(divsrc));
221 divsrc.sin_len = sizeof(divsrc);
222 divsrc.sin_family = AF_INET;
223 /* record matching rule, in host format */
224 divsrc.sin_port = ((struct ipfw_rule_ref *)(mtag+1))->rulenum;
225 /*
226 * Record receive interface address, if any.
227 * But only for incoming packets.
228 */
229 if (incoming) {
230 struct ifaddr *ifa;
231 struct ifnet *ifp;
232
233 /* Sanity check */
234 M_ASSERTPKTHDR(m);
235
236 /* Find IP address for receive interface */
237 ifp = m->m_pkthdr.rcvif;
238 if_addr_rlock(ifp);
239 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
240 if (ifa->ifa_addr->sa_family != AF_INET)
241 continue;
242 divsrc.sin_addr =
243 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr;
244 break;
245 }
246 if_addr_runlock(ifp);
247 }
248 /*
249 * Record the incoming interface name whenever we have one.
250 */
251 if (m->m_pkthdr.rcvif) {
252 /*
253 * Hide the actual interface name in there in the
254 * sin_zero array. XXX This needs to be moved to a
255 * different sockaddr type for divert, e.g.
256 * sockaddr_div with multiple fields like
257 * sockaddr_dl. Presently we have only 7 bytes
258 * but that will do for now as most interfaces
259 * are 4 or less + 2 or less bytes for unit.
260 * There is probably a faster way of doing this,
261 * possibly taking it from the sockaddr_dl on the iface.
262 * This solves the problem of a P2P link and a LAN interface
263 * having the same address, which can result in the wrong
264 * interface being assigned to the packet when fed back
265 * into the divert socket. Theoretically if the daemon saves
266 * and re-uses the sockaddr_in as suggested in the man pages,
267 * this iface name will come along for the ride.
268 * (see div_output for the other half of this.)
269 */
270 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname,
271 sizeof(divsrc.sin_zero));
272 }
273
274 /* Put packet on socket queue, if any */
275 sa = NULL;
276 nport = htons((u_int16_t)(((struct ipfw_rule_ref *)(mtag+1))->info));
277 INP_INFO_RLOCK(&V_divcbinfo);
278 LIST_FOREACH(inp, &V_divcb, inp_list) {
279 /* XXX why does only one socket match? */
280 if (inp->inp_lport == nport) {
281 INP_RLOCK(inp);
282 sa = inp->inp_socket;
283 SOCKBUF_LOCK(&sa->so_rcv);
284 if (sbappendaddr_locked(&sa->so_rcv,
285 (struct sockaddr *)&divsrc, m,
286 (struct mbuf *)0) == 0) {
287 SOCKBUF_UNLOCK(&sa->so_rcv);
288 sa = NULL; /* force mbuf reclaim below */
289 } else
290 sorwakeup_locked(sa);
291 INP_RUNLOCK(inp);
292 break;
293 }
294 }
295 INP_INFO_RUNLOCK(&V_divcbinfo);
296 if (sa == NULL) {
297 m_freem(m);
298 KMOD_IPSTAT_INC(ips_noproto);
299 KMOD_IPSTAT_DEC(ips_delivered);
300 }
301 }
302
303 /*
304 * Deliver packet back into the IP processing machinery.
305 *
306 * If no address specified, or address is 0.0.0.0, send to ip_output();
307 * otherwise, send to ip_input() and mark as having been received on
308 * the interface with that address.
309 */
310 static int
311 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin,
312 struct mbuf *control)
313 {
314 struct ip *const ip = mtod(m, struct ip *);
315 struct m_tag *mtag;
316 struct ipfw_rule_ref *dt;
317 int error = 0;
318
319 /*
320 * An mbuf may hasn't come from userland, but we pretend
321 * that it has.
322 */
323 m->m_pkthdr.rcvif = NULL;
324 m->m_nextpkt = NULL;
325 M_SETFIB(m, so->so_fibnum);
326
327 if (control)
328 m_freem(control); /* XXX */
329
330 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
331 if (mtag == NULL) {
332 /* this should be normal */
333 mtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
334 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
335 if (mtag == NULL) {
336 error = ENOBUFS;
337 goto cantsend;
338 }
339 m_tag_prepend(m, mtag);
340 }
341 dt = (struct ipfw_rule_ref *)(mtag+1);
342
343 /* Loopback avoidance and state recovery */
344 if (sin) {
345 int i;
346
347 /* set the starting point. We provide a non-zero slot,
348 * but a non_matching chain_id to skip that info and use
349 * the rulenum/rule_id.
350 */
351 dt->slot = 1; /* dummy, chain_id is invalid */
352 dt->chain_id = 0;
353 dt->rulenum = sin->sin_port+1; /* host format ? */
354 dt->rule_id = 0;
355 /*
356 * Find receive interface with the given name, stuffed
357 * (if it exists) in the sin_zero[] field.
358 * The name is user supplied data so don't trust its size
359 * or that it is zero terminated.
360 */
361 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++)
362 ;
363 if ( i > 0 && i < sizeof(sin->sin_zero))
364 m->m_pkthdr.rcvif = ifunit(sin->sin_zero);
365 }
366
367 /* Reinject packet into the system as incoming or outgoing */
368 if (!sin || sin->sin_addr.s_addr == 0) {
369 struct mbuf *options = NULL;
370 struct inpcb *inp;
371
372 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_OUT;
373 inp = sotoinpcb(so);
374 INP_RLOCK(inp);
375 switch (ip->ip_v) {
376 case IPVERSION:
377 /*
378 * Don't allow both user specified and setsockopt
379 * options, and don't allow packet length sizes that
380 * will crash.
381 */
382 if ((((ip->ip_hl << 2) != sizeof(struct ip)) &&
383 inp->inp_options != NULL) ||
384 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) {
385 error = EINVAL;
386 INP_RUNLOCK(inp);
387 goto cantsend;
388 }
389 break;
390 #ifdef INET6
391 case IPV6_VERSION >> 4:
392 {
393 struct ip6_hdr *const ip6 = mtod(m, struct ip6_hdr *);
394
395 /* Don't allow packet length sizes that will crash */
396 if (((u_short)ntohs(ip6->ip6_plen) > m->m_pkthdr.len)) {
397 error = EINVAL;
398 INP_RUNLOCK(inp);
399 goto cantsend;
400 }
401 break;
402 }
403 #endif
404 default:
405 error = EINVAL;
406 INP_RUNLOCK(inp);
407 goto cantsend;
408 }
409
410 /* Send packet to output processing */
411 KMOD_IPSTAT_INC(ips_rawout); /* XXX */
412
413 #ifdef MAC
414 mac_inpcb_create_mbuf(inp, m);
415 #endif
416 /*
417 * Get ready to inject the packet into ip_output().
418 * Just in case socket options were specified on the
419 * divert socket, we duplicate them. This is done
420 * to avoid having to hold the PCB locks over the call
421 * to ip_output(), as doing this results in a number of
422 * lock ordering complexities.
423 *
424 * Note that we set the multicast options argument for
425 * ip_output() to NULL since it should be invariant that
426 * they are not present.
427 */
428 KASSERT(inp->inp_moptions == NULL,
429 ("multicast options set on a divert socket"));
430 /*
431 * XXXCSJP: It is unclear to me whether or not it makes
432 * sense for divert sockets to have options. However,
433 * for now we will duplicate them with the INP locks
434 * held so we can use them in ip_output() without
435 * requring a reference to the pcb.
436 */
437 if (inp->inp_options != NULL) {
438 options = m_dup(inp->inp_options, M_NOWAIT);
439 if (options == NULL) {
440 INP_RUNLOCK(inp);
441 error = ENOBUFS;
442 goto cantsend;
443 }
444 }
445 INP_RUNLOCK(inp);
446
447 switch (ip->ip_v) {
448 case IPVERSION:
449 error = ip_output(m, options, NULL,
450 ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0)
451 | IP_ALLOWBROADCAST | IP_RAWOUTPUT, NULL, NULL);
452 break;
453 #ifdef INET6
454 case IPV6_VERSION >> 4:
455 error = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
456 break;
457 #endif
458 }
459 if (options != NULL)
460 m_freem(options);
461 } else {
462 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_IN;
463 if (m->m_pkthdr.rcvif == NULL) {
464 /*
465 * No luck with the name, check by IP address.
466 * Clear the port and the ifname to make sure
467 * there are no distractions for ifa_ifwithaddr.
468 */
469 struct ifaddr *ifa;
470
471 bzero(sin->sin_zero, sizeof(sin->sin_zero));
472 sin->sin_port = 0;
473 ifa = ifa_ifwithaddr((struct sockaddr *) sin);
474 if (ifa == NULL) {
475 error = EADDRNOTAVAIL;
476 goto cantsend;
477 }
478 m->m_pkthdr.rcvif = ifa->ifa_ifp;
479 ifa_free(ifa);
480 }
481 #ifdef MAC
482 mac_socket_create_mbuf(so, m);
483 #endif
484 /* Send packet to input processing via netisr */
485 switch (ip->ip_v) {
486 case IPVERSION:
487 netisr_queue_src(NETISR_IP, (uintptr_t)so, m);
488 break;
489 #ifdef INET6
490 case IPV6_VERSION >> 4:
491 netisr_queue_src(NETISR_IPV6, (uintptr_t)so, m);
492 break;
493 #endif
494 default:
495 error = EINVAL;
496 goto cantsend;
497 }
498 }
499
500 return (error);
501
502 cantsend:
503 m_freem(m);
504 return (error);
505 }
506
507 static int
508 div_attach(struct socket *so, int proto, struct thread *td)
509 {
510 struct inpcb *inp;
511 int error;
512
513 inp = sotoinpcb(so);
514 KASSERT(inp == NULL, ("div_attach: inp != NULL"));
515 if (td != NULL) {
516 error = priv_check(td, PRIV_NETINET_DIVERT);
517 if (error)
518 return (error);
519 }
520 error = soreserve(so, div_sendspace, div_recvspace);
521 if (error)
522 return error;
523 INP_INFO_WLOCK(&V_divcbinfo);
524 error = in_pcballoc(so, &V_divcbinfo);
525 if (error) {
526 INP_INFO_WUNLOCK(&V_divcbinfo);
527 return error;
528 }
529 inp = (struct inpcb *)so->so_pcb;
530 INP_INFO_WUNLOCK(&V_divcbinfo);
531 inp->inp_ip_p = proto;
532 inp->inp_vflag |= INP_IPV4;
533 inp->inp_flags |= INP_HDRINCL;
534 INP_WUNLOCK(inp);
535 return 0;
536 }
537
538 static void
539 div_detach(struct socket *so)
540 {
541 struct inpcb *inp;
542
543 inp = sotoinpcb(so);
544 KASSERT(inp != NULL, ("div_detach: inp == NULL"));
545 INP_INFO_WLOCK(&V_divcbinfo);
546 INP_WLOCK(inp);
547 in_pcbdetach(inp);
548 in_pcbfree(inp);
549 INP_INFO_WUNLOCK(&V_divcbinfo);
550 }
551
552 static int
553 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
554 {
555 struct inpcb *inp;
556 int error;
557
558 inp = sotoinpcb(so);
559 KASSERT(inp != NULL, ("div_bind: inp == NULL"));
560 /* in_pcbbind assumes that nam is a sockaddr_in
561 * and in_pcbbind requires a valid address. Since divert
562 * sockets don't we need to make sure the address is
563 * filled in properly.
564 * XXX -- divert should not be abusing in_pcbind
565 * and should probably have its own family.
566 */
567 if (nam->sa_family != AF_INET)
568 return EAFNOSUPPORT;
569 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY;
570 INP_INFO_WLOCK(&V_divcbinfo);
571 INP_WLOCK(inp);
572 INP_HASH_WLOCK(&V_divcbinfo);
573 error = in_pcbbind(inp, nam, td->td_ucred);
574 INP_HASH_WUNLOCK(&V_divcbinfo);
575 INP_WUNLOCK(inp);
576 INP_INFO_WUNLOCK(&V_divcbinfo);
577 return error;
578 }
579
580 static int
581 div_shutdown(struct socket *so)
582 {
583 struct inpcb *inp;
584
585 inp = sotoinpcb(so);
586 KASSERT(inp != NULL, ("div_shutdown: inp == NULL"));
587 INP_WLOCK(inp);
588 socantsendmore(so);
589 INP_WUNLOCK(inp);
590 return 0;
591 }
592
593 static int
594 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
595 struct mbuf *control, struct thread *td)
596 {
597
598 /* Packet must have a header (but that's about it) */
599 if (m->m_len < sizeof (struct ip) &&
600 (m = m_pullup(m, sizeof (struct ip))) == 0) {
601 KMOD_IPSTAT_INC(ips_toosmall);
602 m_freem(m);
603 return EINVAL;
604 }
605
606 /* Send packet */
607 return div_output(so, m, (struct sockaddr_in *)nam, control);
608 }
609
610 static void
611 div_ctlinput(int cmd, struct sockaddr *sa, void *vip)
612 {
613 struct in_addr faddr;
614
615 faddr = ((struct sockaddr_in *)sa)->sin_addr;
616 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
617 return;
618 if (PRC_IS_REDIRECT(cmd))
619 return;
620 }
621
622 static int
623 div_pcblist(SYSCTL_HANDLER_ARGS)
624 {
625 int error, i, n;
626 struct inpcb *inp, **inp_list;
627 inp_gen_t gencnt;
628 struct xinpgen xig;
629
630 /*
631 * The process of preparing the TCB list is too time-consuming and
632 * resource-intensive to repeat twice on every request.
633 */
634 if (req->oldptr == 0) {
635 n = V_divcbinfo.ipi_count;
636 n += imax(n / 8, 10);
637 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
638 return 0;
639 }
640
641 if (req->newptr != 0)
642 return EPERM;
643
644 /*
645 * OK, now we're committed to doing something.
646 */
647 INP_INFO_RLOCK(&V_divcbinfo);
648 gencnt = V_divcbinfo.ipi_gencnt;
649 n = V_divcbinfo.ipi_count;
650 INP_INFO_RUNLOCK(&V_divcbinfo);
651
652 error = sysctl_wire_old_buffer(req,
653 2 * sizeof(xig) + n*sizeof(struct xinpcb));
654 if (error != 0)
655 return (error);
656
657 xig.xig_len = sizeof xig;
658 xig.xig_count = n;
659 xig.xig_gen = gencnt;
660 xig.xig_sogen = so_gencnt;
661 error = SYSCTL_OUT(req, &xig, sizeof xig);
662 if (error)
663 return error;
664
665 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
666 if (inp_list == 0)
667 return ENOMEM;
668
669 INP_INFO_RLOCK(&V_divcbinfo);
670 for (inp = LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n;
671 inp = LIST_NEXT(inp, inp_list)) {
672 INP_WLOCK(inp);
673 if (inp->inp_gencnt <= gencnt &&
674 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
675 in_pcbref(inp);
676 inp_list[i++] = inp;
677 }
678 INP_WUNLOCK(inp);
679 }
680 INP_INFO_RUNLOCK(&V_divcbinfo);
681 n = i;
682
683 error = 0;
684 for (i = 0; i < n; i++) {
685 inp = inp_list[i];
686 INP_RLOCK(inp);
687 if (inp->inp_gencnt <= gencnt) {
688 struct xinpcb xi;
689 bzero(&xi, sizeof(xi));
690 xi.xi_len = sizeof xi;
691 /* XXX should avoid extra copy */
692 bcopy(inp, &xi.xi_inp, sizeof *inp);
693 if (inp->inp_socket)
694 sotoxsocket(inp->inp_socket, &xi.xi_socket);
695 INP_RUNLOCK(inp);
696 error = SYSCTL_OUT(req, &xi, sizeof xi);
697 } else
698 INP_RUNLOCK(inp);
699 }
700 INP_INFO_WLOCK(&V_divcbinfo);
701 for (i = 0; i < n; i++) {
702 inp = inp_list[i];
703 INP_RLOCK(inp);
704 if (!in_pcbrele_rlocked(inp))
705 INP_RUNLOCK(inp);
706 }
707 INP_INFO_WUNLOCK(&V_divcbinfo);
708
709 if (!error) {
710 /*
711 * Give the user an updated idea of our state.
712 * If the generation differs from what we told
713 * her before, she knows that something happened
714 * while we were processing this request, and it
715 * might be necessary to retry.
716 */
717 INP_INFO_RLOCK(&V_divcbinfo);
718 xig.xig_gen = V_divcbinfo.ipi_gencnt;
719 xig.xig_sogen = so_gencnt;
720 xig.xig_count = V_divcbinfo.ipi_count;
721 INP_INFO_RUNLOCK(&V_divcbinfo);
722 error = SYSCTL_OUT(req, &xig, sizeof xig);
723 }
724 free(inp_list, M_TEMP);
725 return error;
726 }
727
728 #ifdef SYSCTL_NODE
729 static SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0,
730 "IPDIVERT");
731 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD,
732 NULL, 0, div_pcblist, "S,xinpcb", "List of active divert sockets");
733 #endif
734
735 struct pr_usrreqs div_usrreqs = {
736 .pru_attach = div_attach,
737 .pru_bind = div_bind,
738 .pru_control = in_control,
739 .pru_detach = div_detach,
740 .pru_peeraddr = in_getpeeraddr,
741 .pru_send = div_send,
742 .pru_shutdown = div_shutdown,
743 .pru_sockaddr = in_getsockaddr,
744 .pru_sosetlabel = in_pcbsosetlabel
745 };
746
747 struct protosw div_protosw = {
748 .pr_type = SOCK_RAW,
749 .pr_protocol = IPPROTO_DIVERT,
750 .pr_flags = PR_ATOMIC|PR_ADDR,
751 .pr_input = div_input,
752 .pr_ctlinput = div_ctlinput,
753 .pr_ctloutput = ip_ctloutput,
754 .pr_init = div_init,
755 #ifdef VIMAGE
756 .pr_destroy = div_destroy,
757 #endif
758 .pr_usrreqs = &div_usrreqs
759 };
760
761 static int
762 div_modevent(module_t mod, int type, void *unused)
763 {
764 int err = 0;
765 #ifndef VIMAGE
766 int n;
767 #endif
768
769 switch (type) {
770 case MOD_LOAD:
771 /*
772 * Protocol will be initialized by pf_proto_register().
773 * We don't have to register ip_protox because we are not
774 * a true IP protocol that goes over the wire.
775 */
776 err = pf_proto_register(PF_INET, &div_protosw);
777 if (err != 0)
778 return (err);
779 ip_divert_ptr = divert_packet;
780 ip_divert_event_tag = EVENTHANDLER_REGISTER(maxsockets_change,
781 div_zone_change, NULL, EVENTHANDLER_PRI_ANY);
782 break;
783 case MOD_QUIESCE:
784 /*
785 * IPDIVERT may normally not be unloaded because of the
786 * potential race conditions. Tell kldunload we can't be
787 * unloaded unless the unload is forced.
788 */
789 err = EPERM;
790 break;
791 case MOD_UNLOAD:
792 #ifdef VIMAGE
793 err = EPERM;
794 break;
795 #else
796 /*
797 * Forced unload.
798 *
799 * Module ipdivert can only be unloaded if no sockets are
800 * connected. Maybe this can be changed later to forcefully
801 * disconnect any open sockets.
802 *
803 * XXXRW: Note that there is a slight race here, as a new
804 * socket open request could be spinning on the lock and then
805 * we destroy the lock.
806 */
807 INP_INFO_WLOCK(&V_divcbinfo);
808 n = V_divcbinfo.ipi_count;
809 if (n != 0) {
810 err = EBUSY;
811 INP_INFO_WUNLOCK(&V_divcbinfo);
812 break;
813 }
814 ip_divert_ptr = NULL;
815 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW);
816 INP_INFO_WUNLOCK(&V_divcbinfo);
817 div_destroy();
818 EVENTHANDLER_DEREGISTER(maxsockets_change, ip_divert_event_tag);
819 break;
820 #endif /* !VIMAGE */
821 default:
822 err = EOPNOTSUPP;
823 break;
824 }
825 return err;
826 }
827
828 static moduledata_t ipdivertmod = {
829 "ipdivert",
830 div_modevent,
831 0
832 };
833
834 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY);
835 MODULE_DEPEND(ipdivert, ipfw, 2, 2, 2);
836 MODULE_VERSION(ipdivert, 1);
Cache object: 1da2248da89463d08edb5ccb0ea7ddf3
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