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: releng/8.0/sys/netinet/ip_divert.c 196621 2009-08-28 19:10:58Z zec $");
32
33 #if !defined(KLD_MODULE)
34 #include "opt_inet.h"
35 #include "opt_ipfw.h"
36 #include "opt_sctp.h"
37 #ifndef INET
38 #error "IPDIVERT requires INET."
39 #endif
40 #ifndef IPFIREWALL
41 #error "IPDIVERT requires IPFIREWALL"
42 #endif
43 #endif
44
45 #include <sys/param.h>
46 #include <sys/kernel.h>
47 #include <sys/lock.h>
48 #include <sys/malloc.h>
49 #include <sys/mbuf.h>
50 #include <sys/module.h>
51 #include <sys/kernel.h>
52 #include <sys/priv.h>
53 #include <sys/proc.h>
54 #include <sys/protosw.h>
55 #include <sys/rwlock.h>
56 #include <sys/signalvar.h>
57 #include <sys/socket.h>
58 #include <sys/socketvar.h>
59 #include <sys/sx.h>
60 #include <sys/sysctl.h>
61 #include <sys/systm.h>
62
63 #include <vm/uma.h>
64
65 #include <net/if.h>
66 #include <net/netisr.h>
67 #include <net/route.h>
68 #include <net/vnet.h>
69
70 #include <netinet/in.h>
71 #include <netinet/in_pcb.h>
72 #include <netinet/in_systm.h>
73 #include <netinet/in_var.h>
74 #include <netinet/ip.h>
75 #include <netinet/ip_divert.h>
76 #include <netinet/ip_var.h>
77 #include <netinet/ip_fw.h>
78 #ifdef SCTP
79 #include <netinet/sctp_crc32.h>
80 #endif
81
82 #include <security/mac/mac_framework.h>
83
84 /*
85 * Divert sockets
86 */
87
88 /*
89 * Allocate enough space to hold a full IP packet
90 */
91 #define DIVSNDQ (65536 + 100)
92 #define DIVRCVQ (65536 + 100)
93
94 /*
95 * Divert sockets work in conjunction with ipfw, see the divert(4)
96 * manpage for features.
97 * Internally, packets selected by ipfw in ip_input() or ip_output(),
98 * and never diverted before, are passed to the input queue of the
99 * divert socket with a given 'divert_port' number (as specified in
100 * the matching ipfw rule), and they are tagged with a 16 bit cookie
101 * (representing the rule number of the matching ipfw rule), which
102 * is passed to process reading from the socket.
103 *
104 * Packets written to the divert socket are again tagged with a cookie
105 * (usually the same as above) and a destination address.
106 * If the destination address is INADDR_ANY then the packet is
107 * treated as outgoing and sent to ip_output(), otherwise it is
108 * treated as incoming and sent to ip_input().
109 * In both cases, the packet is tagged with the cookie.
110 *
111 * On reinjection, processing in ip_input() and ip_output()
112 * will be exactly the same as for the original packet, except that
113 * ipfw processing will start at the rule number after the one
114 * written in the cookie (so, tagging a packet with a cookie of 0
115 * will cause it to be effectively considered as a standard packet).
116 */
117
118 /* Internal variables. */
119 static VNET_DEFINE(struct inpcbhead, divcb);
120 static VNET_DEFINE(struct inpcbinfo, divcbinfo);
121
122 #define V_divcb VNET(divcb)
123 #define V_divcbinfo VNET(divcbinfo)
124
125 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */
126 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */
127
128 static eventhandler_tag ip_divert_event_tag;
129
130 /*
131 * Initialize divert connection block queue.
132 */
133 static void
134 div_zone_change(void *tag)
135 {
136
137 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets);
138 }
139
140 static int
141 div_inpcb_init(void *mem, int size, int flags)
142 {
143 struct inpcb *inp = mem;
144
145 INP_LOCK_INIT(inp, "inp", "divinp");
146 return (0);
147 }
148
149 static void
150 div_inpcb_fini(void *mem, int size)
151 {
152 struct inpcb *inp = mem;
153
154 INP_LOCK_DESTROY(inp);
155 }
156
157 static void
158 div_init(void)
159 {
160
161 INP_INFO_LOCK_INIT(&V_divcbinfo, "div");
162 LIST_INIT(&V_divcb);
163 V_divcbinfo.ipi_listhead = &V_divcb;
164 #ifdef VIMAGE
165 V_divcbinfo.ipi_vnet = curvnet;
166 #endif
167 /*
168 * XXX We don't use the hash list for divert IP, but it's easier
169 * to allocate a one entry hash list than it is to check all
170 * over the place for hashbase == NULL.
171 */
172 V_divcbinfo.ipi_hashbase = hashinit(1, M_PCB, &V_divcbinfo.ipi_hashmask);
173 V_divcbinfo.ipi_porthashbase = hashinit(1, M_PCB,
174 &V_divcbinfo.ipi_porthashmask);
175 V_divcbinfo.ipi_zone = uma_zcreate("divcb", sizeof(struct inpcb),
176 NULL, NULL, div_inpcb_init, div_inpcb_fini, UMA_ALIGN_PTR,
177 UMA_ZONE_NOFREE);
178 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets);
179 }
180
181 static void
182 div_destroy(void)
183 {
184
185 INP_INFO_LOCK_DESTROY(&V_divcbinfo);
186 uma_zdestroy(V_divcbinfo.ipi_zone);
187 hashdestroy(V_divcbinfo.ipi_hashbase, M_PCB, V_divcbinfo.ipi_hashmask);
188 hashdestroy(V_divcbinfo.ipi_porthashbase, M_PCB,
189 V_divcbinfo.ipi_porthashmask);
190 }
191
192 /*
193 * IPPROTO_DIVERT is not in the real IP protocol number space; this
194 * function should never be called. Just in case, drop any packets.
195 */
196 void
197 div_input(struct mbuf *m, int off)
198 {
199
200 KMOD_IPSTAT_INC(ips_noproto);
201 m_freem(m);
202 }
203
204 /*
205 * Divert a packet by passing it up to the divert socket at port 'port'.
206 *
207 * Setup generic address and protocol structures for div_input routine,
208 * then pass them along with mbuf chain.
209 */
210 static void
211 divert_packet(struct mbuf *m, int incoming)
212 {
213 struct ip *ip;
214 struct inpcb *inp;
215 struct socket *sa;
216 u_int16_t nport;
217 struct sockaddr_in divsrc;
218 struct m_tag *mtag;
219
220 mtag = m_tag_find(m, PACKET_TAG_DIVERT, NULL);
221 if (mtag == NULL) {
222 printf("%s: no divert tag\n", __func__);
223 m_freem(m);
224 return;
225 }
226 /* Assure header */
227 if (m->m_len < sizeof(struct ip) &&
228 (m = m_pullup(m, sizeof(struct ip))) == 0)
229 return;
230 ip = mtod(m, struct ip *);
231
232 /* Delayed checksums are currently not compatible with divert. */
233 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
234 ip->ip_len = ntohs(ip->ip_len);
235 in_delayed_cksum(m);
236 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
237 ip->ip_len = htons(ip->ip_len);
238 }
239 #ifdef SCTP
240 if (m->m_pkthdr.csum_flags & CSUM_SCTP) {
241 ip->ip_len = ntohs(ip->ip_len);
242 sctp_delayed_cksum(m);
243 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
244 ip->ip_len = htons(ip->ip_len);
245 }
246 #endif
247 /*
248 * Record receive interface address, if any.
249 * But only for incoming packets.
250 */
251 bzero(&divsrc, sizeof(divsrc));
252 divsrc.sin_len = sizeof(divsrc);
253 divsrc.sin_family = AF_INET;
254 divsrc.sin_port = divert_cookie(mtag); /* record matching rule */
255 if (incoming) {
256 struct ifaddr *ifa;
257 struct ifnet *ifp;
258
259 /* Sanity check */
260 M_ASSERTPKTHDR(m);
261
262 /* Find IP address for receive interface */
263 ifp = m->m_pkthdr.rcvif;
264 if_addr_rlock(ifp);
265 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
266 if (ifa->ifa_addr->sa_family != AF_INET)
267 continue;
268 divsrc.sin_addr =
269 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr;
270 break;
271 }
272 if_addr_runlock(ifp);
273 }
274 /*
275 * Record the incoming interface name whenever we have one.
276 */
277 if (m->m_pkthdr.rcvif) {
278 /*
279 * Hide the actual interface name in there in the
280 * sin_zero array. XXX This needs to be moved to a
281 * different sockaddr type for divert, e.g.
282 * sockaddr_div with multiple fields like
283 * sockaddr_dl. Presently we have only 7 bytes
284 * but that will do for now as most interfaces
285 * are 4 or less + 2 or less bytes for unit.
286 * There is probably a faster way of doing this,
287 * possibly taking it from the sockaddr_dl on the iface.
288 * This solves the problem of a P2P link and a LAN interface
289 * having the same address, which can result in the wrong
290 * interface being assigned to the packet when fed back
291 * into the divert socket. Theoretically if the daemon saves
292 * and re-uses the sockaddr_in as suggested in the man pages,
293 * this iface name will come along for the ride.
294 * (see div_output for the other half of this.)
295 */
296 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname,
297 sizeof(divsrc.sin_zero));
298 }
299
300 /* Put packet on socket queue, if any */
301 sa = NULL;
302 nport = htons((u_int16_t)divert_info(mtag));
303 INP_INFO_RLOCK(&V_divcbinfo);
304 LIST_FOREACH(inp, &V_divcb, inp_list) {
305 /* XXX why does only one socket match? */
306 if (inp->inp_lport == nport) {
307 INP_RLOCK(inp);
308 sa = inp->inp_socket;
309 SOCKBUF_LOCK(&sa->so_rcv);
310 if (sbappendaddr_locked(&sa->so_rcv,
311 (struct sockaddr *)&divsrc, m,
312 (struct mbuf *)0) == 0) {
313 SOCKBUF_UNLOCK(&sa->so_rcv);
314 sa = NULL; /* force mbuf reclaim below */
315 } else
316 sorwakeup_locked(sa);
317 INP_RUNLOCK(inp);
318 break;
319 }
320 }
321 INP_INFO_RUNLOCK(&V_divcbinfo);
322 if (sa == NULL) {
323 m_freem(m);
324 KMOD_IPSTAT_INC(ips_noproto);
325 KMOD_IPSTAT_DEC(ips_delivered);
326 }
327 }
328
329 /*
330 * Deliver packet back into the IP processing machinery.
331 *
332 * If no address specified, or address is 0.0.0.0, send to ip_output();
333 * otherwise, send to ip_input() and mark as having been received on
334 * the interface with that address.
335 */
336 static int
337 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin,
338 struct mbuf *control)
339 {
340 struct m_tag *mtag;
341 struct divert_tag *dt;
342 int error = 0;
343 struct mbuf *options;
344
345 /*
346 * An mbuf may hasn't come from userland, but we pretend
347 * that it has.
348 */
349 m->m_pkthdr.rcvif = NULL;
350 m->m_nextpkt = NULL;
351 M_SETFIB(m, so->so_fibnum);
352
353 if (control)
354 m_freem(control); /* XXX */
355
356 if ((mtag = m_tag_find(m, PACKET_TAG_DIVERT, NULL)) == NULL) {
357 mtag = m_tag_get(PACKET_TAG_DIVERT, sizeof(struct divert_tag),
358 M_NOWAIT | M_ZERO);
359 if (mtag == NULL) {
360 error = ENOBUFS;
361 goto cantsend;
362 }
363 dt = (struct divert_tag *)(mtag+1);
364 m_tag_prepend(m, mtag);
365 } else
366 dt = (struct divert_tag *)(mtag+1);
367
368 /* Loopback avoidance and state recovery */
369 if (sin) {
370 int i;
371
372 dt->cookie = sin->sin_port;
373 /*
374 * Find receive interface with the given name, stuffed
375 * (if it exists) in the sin_zero[] field.
376 * The name is user supplied data so don't trust its size
377 * or that it is zero terminated.
378 */
379 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++)
380 ;
381 if ( i > 0 && i < sizeof(sin->sin_zero))
382 m->m_pkthdr.rcvif = ifunit(sin->sin_zero);
383 }
384
385 /* Reinject packet into the system as incoming or outgoing */
386 if (!sin || sin->sin_addr.s_addr == 0) {
387 struct ip *const ip = mtod(m, struct ip *);
388 struct inpcb *inp;
389
390 dt->info |= IP_FW_DIVERT_OUTPUT_FLAG;
391 INP_INFO_WLOCK(&V_divcbinfo);
392 inp = sotoinpcb(so);
393 INP_RLOCK(inp);
394 /*
395 * Don't allow both user specified and setsockopt options,
396 * and don't allow packet length sizes that will crash
397 */
398 if (((ip->ip_hl != (sizeof (*ip) >> 2)) && inp->inp_options) ||
399 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) {
400 error = EINVAL;
401 INP_RUNLOCK(inp);
402 INP_INFO_WUNLOCK(&V_divcbinfo);
403 m_freem(m);
404 } else {
405 /* Convert fields to host order for ip_output() */
406 ip->ip_len = ntohs(ip->ip_len);
407 ip->ip_off = ntohs(ip->ip_off);
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 options = NULL;
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_DONTWAIT);
439 if (options == NULL)
440 error = ENOBUFS;
441 }
442 INP_RUNLOCK(inp);
443 INP_INFO_WUNLOCK(&V_divcbinfo);
444 if (error == ENOBUFS) {
445 m_freem(m);
446 return (error);
447 }
448 error = ip_output(m, options, NULL,
449 ((so->so_options & SO_DONTROUTE) ?
450 IP_ROUTETOIF : 0) | IP_ALLOWBROADCAST |
451 IP_RAWOUTPUT, NULL, NULL);
452 if (options != NULL)
453 m_freem(options);
454 }
455 } else {
456 dt->info |= IP_FW_DIVERT_LOOPBACK_FLAG;
457 if (m->m_pkthdr.rcvif == NULL) {
458 /*
459 * No luck with the name, check by IP address.
460 * Clear the port and the ifname to make sure
461 * there are no distractions for ifa_ifwithaddr.
462 */
463 struct ifaddr *ifa;
464
465 bzero(sin->sin_zero, sizeof(sin->sin_zero));
466 sin->sin_port = 0;
467 ifa = ifa_ifwithaddr((struct sockaddr *) sin);
468 if (ifa == NULL) {
469 error = EADDRNOTAVAIL;
470 goto cantsend;
471 }
472 m->m_pkthdr.rcvif = ifa->ifa_ifp;
473 ifa_free(ifa);
474 }
475 #ifdef MAC
476 mac_socket_create_mbuf(so, m);
477 #endif
478 /* Send packet to input processing via netisr */
479 netisr_queue_src(NETISR_IP, (uintptr_t)so, m);
480 }
481
482 return error;
483
484 cantsend:
485 m_freem(m);
486 return error;
487 }
488
489 static int
490 div_attach(struct socket *so, int proto, struct thread *td)
491 {
492 struct inpcb *inp;
493 int error;
494
495 inp = sotoinpcb(so);
496 KASSERT(inp == NULL, ("div_attach: inp != NULL"));
497 if (td != NULL) {
498 error = priv_check(td, PRIV_NETINET_DIVERT);
499 if (error)
500 return (error);
501 }
502 error = soreserve(so, div_sendspace, div_recvspace);
503 if (error)
504 return error;
505 INP_INFO_WLOCK(&V_divcbinfo);
506 error = in_pcballoc(so, &V_divcbinfo);
507 if (error) {
508 INP_INFO_WUNLOCK(&V_divcbinfo);
509 return error;
510 }
511 inp = (struct inpcb *)so->so_pcb;
512 INP_INFO_WUNLOCK(&V_divcbinfo);
513 inp->inp_ip_p = proto;
514 inp->inp_vflag |= INP_IPV4;
515 inp->inp_flags |= INP_HDRINCL;
516 INP_WUNLOCK(inp);
517 return 0;
518 }
519
520 static void
521 div_detach(struct socket *so)
522 {
523 struct inpcb *inp;
524
525 inp = sotoinpcb(so);
526 KASSERT(inp != NULL, ("div_detach: inp == NULL"));
527 INP_INFO_WLOCK(&V_divcbinfo);
528 INP_WLOCK(inp);
529 in_pcbdetach(inp);
530 in_pcbfree(inp);
531 INP_INFO_WUNLOCK(&V_divcbinfo);
532 }
533
534 static int
535 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
536 {
537 struct inpcb *inp;
538 int error;
539
540 inp = sotoinpcb(so);
541 KASSERT(inp != NULL, ("div_bind: inp == NULL"));
542 /* in_pcbbind assumes that nam is a sockaddr_in
543 * and in_pcbbind requires a valid address. Since divert
544 * sockets don't we need to make sure the address is
545 * filled in properly.
546 * XXX -- divert should not be abusing in_pcbind
547 * and should probably have its own family.
548 */
549 if (nam->sa_family != AF_INET)
550 return EAFNOSUPPORT;
551 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY;
552 INP_INFO_WLOCK(&V_divcbinfo);
553 INP_WLOCK(inp);
554 error = in_pcbbind(inp, nam, td->td_ucred);
555 INP_WUNLOCK(inp);
556 INP_INFO_WUNLOCK(&V_divcbinfo);
557 return error;
558 }
559
560 static int
561 div_shutdown(struct socket *so)
562 {
563 struct inpcb *inp;
564
565 inp = sotoinpcb(so);
566 KASSERT(inp != NULL, ("div_shutdown: inp == NULL"));
567 INP_WLOCK(inp);
568 socantsendmore(so);
569 INP_WUNLOCK(inp);
570 return 0;
571 }
572
573 static int
574 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
575 struct mbuf *control, struct thread *td)
576 {
577
578 /* Packet must have a header (but that's about it) */
579 if (m->m_len < sizeof (struct ip) &&
580 (m = m_pullup(m, sizeof (struct ip))) == 0) {
581 KMOD_IPSTAT_INC(ips_toosmall);
582 m_freem(m);
583 return EINVAL;
584 }
585
586 /* Send packet */
587 return div_output(so, m, (struct sockaddr_in *)nam, control);
588 }
589
590 void
591 div_ctlinput(int cmd, struct sockaddr *sa, void *vip)
592 {
593 struct in_addr faddr;
594
595 faddr = ((struct sockaddr_in *)sa)->sin_addr;
596 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
597 return;
598 if (PRC_IS_REDIRECT(cmd))
599 return;
600 }
601
602 static int
603 div_pcblist(SYSCTL_HANDLER_ARGS)
604 {
605 int error, i, n;
606 struct inpcb *inp, **inp_list;
607 inp_gen_t gencnt;
608 struct xinpgen xig;
609
610 /*
611 * The process of preparing the TCB list is too time-consuming and
612 * resource-intensive to repeat twice on every request.
613 */
614 if (req->oldptr == 0) {
615 n = V_divcbinfo.ipi_count;
616 req->oldidx = 2 * (sizeof xig)
617 + (n + n/8) * sizeof(struct xinpcb);
618 return 0;
619 }
620
621 if (req->newptr != 0)
622 return EPERM;
623
624 /*
625 * OK, now we're committed to doing something.
626 */
627 INP_INFO_RLOCK(&V_divcbinfo);
628 gencnt = V_divcbinfo.ipi_gencnt;
629 n = V_divcbinfo.ipi_count;
630 INP_INFO_RUNLOCK(&V_divcbinfo);
631
632 error = sysctl_wire_old_buffer(req,
633 2 * sizeof(xig) + n*sizeof(struct xinpcb));
634 if (error != 0)
635 return (error);
636
637 xig.xig_len = sizeof xig;
638 xig.xig_count = n;
639 xig.xig_gen = gencnt;
640 xig.xig_sogen = so_gencnt;
641 error = SYSCTL_OUT(req, &xig, sizeof xig);
642 if (error)
643 return error;
644
645 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
646 if (inp_list == 0)
647 return ENOMEM;
648
649 INP_INFO_RLOCK(&V_divcbinfo);
650 for (inp = LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n;
651 inp = LIST_NEXT(inp, inp_list)) {
652 INP_RLOCK(inp);
653 if (inp->inp_gencnt <= gencnt &&
654 cr_canseeinpcb(req->td->td_ucred, inp) == 0)
655 inp_list[i++] = inp;
656 INP_RUNLOCK(inp);
657 }
658 INP_INFO_RUNLOCK(&V_divcbinfo);
659 n = i;
660
661 error = 0;
662 for (i = 0; i < n; i++) {
663 inp = inp_list[i];
664 INP_RLOCK(inp);
665 if (inp->inp_gencnt <= gencnt) {
666 struct xinpcb xi;
667 bzero(&xi, sizeof(xi));
668 xi.xi_len = sizeof xi;
669 /* XXX should avoid extra copy */
670 bcopy(inp, &xi.xi_inp, sizeof *inp);
671 if (inp->inp_socket)
672 sotoxsocket(inp->inp_socket, &xi.xi_socket);
673 INP_RUNLOCK(inp);
674 error = SYSCTL_OUT(req, &xi, sizeof xi);
675 } else
676 INP_RUNLOCK(inp);
677 }
678 if (!error) {
679 /*
680 * Give the user an updated idea of our state.
681 * If the generation differs from what we told
682 * her before, she knows that something happened
683 * while we were processing this request, and it
684 * might be necessary to retry.
685 */
686 INP_INFO_RLOCK(&V_divcbinfo);
687 xig.xig_gen = V_divcbinfo.ipi_gencnt;
688 xig.xig_sogen = so_gencnt;
689 xig.xig_count = V_divcbinfo.ipi_count;
690 INP_INFO_RUNLOCK(&V_divcbinfo);
691 error = SYSCTL_OUT(req, &xig, sizeof xig);
692 }
693 free(inp_list, M_TEMP);
694 return error;
695 }
696
697 #ifdef SYSCTL_NODE
698 SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0, "IPDIVERT");
699 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLFLAG_RD, 0, 0,
700 div_pcblist, "S,xinpcb", "List of active divert sockets");
701 #endif
702
703 struct pr_usrreqs div_usrreqs = {
704 .pru_attach = div_attach,
705 .pru_bind = div_bind,
706 .pru_control = in_control,
707 .pru_detach = div_detach,
708 .pru_peeraddr = in_getpeeraddr,
709 .pru_send = div_send,
710 .pru_shutdown = div_shutdown,
711 .pru_sockaddr = in_getsockaddr,
712 .pru_sosetlabel = in_pcbsosetlabel
713 };
714
715 struct protosw div_protosw = {
716 .pr_type = SOCK_RAW,
717 .pr_protocol = IPPROTO_DIVERT,
718 .pr_flags = PR_ATOMIC|PR_ADDR,
719 .pr_input = div_input,
720 .pr_ctlinput = div_ctlinput,
721 .pr_ctloutput = ip_ctloutput,
722 .pr_init = div_init,
723 #ifdef VIMAGE
724 .pr_destroy = div_destroy,
725 #endif
726 .pr_usrreqs = &div_usrreqs
727 };
728
729 static int
730 div_modevent(module_t mod, int type, void *unused)
731 {
732 int err = 0;
733 #ifndef VIMAGE
734 int n;
735 #endif
736
737 switch (type) {
738 case MOD_LOAD:
739 /*
740 * Protocol will be initialized by pf_proto_register().
741 * We don't have to register ip_protox because we are not
742 * a true IP protocol that goes over the wire.
743 */
744 err = pf_proto_register(PF_INET, &div_protosw);
745 if (err != 0)
746 return (err);
747 ip_divert_ptr = divert_packet;
748 ip_divert_event_tag = EVENTHANDLER_REGISTER(maxsockets_change,
749 div_zone_change, NULL, EVENTHANDLER_PRI_ANY);
750 break;
751 case MOD_QUIESCE:
752 /*
753 * IPDIVERT may normally not be unloaded because of the
754 * potential race conditions. Tell kldunload we can't be
755 * unloaded unless the unload is forced.
756 */
757 err = EPERM;
758 break;
759 case MOD_UNLOAD:
760 #ifdef VIMAGE
761 err = EPERM;
762 break;
763 #else
764 /*
765 * Forced unload.
766 *
767 * Module ipdivert can only be unloaded if no sockets are
768 * connected. Maybe this can be changed later to forcefully
769 * disconnect any open sockets.
770 *
771 * XXXRW: Note that there is a slight race here, as a new
772 * socket open request could be spinning on the lock and then
773 * we destroy the lock.
774 */
775 INP_INFO_WLOCK(&V_divcbinfo);
776 n = V_divcbinfo.ipi_count;
777 if (n != 0) {
778 err = EBUSY;
779 INP_INFO_WUNLOCK(&V_divcbinfo);
780 break;
781 }
782 ip_divert_ptr = NULL;
783 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW);
784 INP_INFO_WUNLOCK(&V_divcbinfo);
785 div_destroy();
786 EVENTHANDLER_DEREGISTER(maxsockets_change, ip_divert_event_tag);
787 break;
788 #endif /* !VIMAGE */
789 default:
790 err = EOPNOTSUPP;
791 break;
792 }
793 return err;
794 }
795
796 static moduledata_t ipdivertmod = {
797 "ipdivert",
798 div_modevent,
799 0
800 };
801
802 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY);
803 MODULE_DEPEND(dummynet, ipfw, 2, 2, 2);
804 MODULE_VERSION(ipdivert, 1);
Cache object: e79d2e1a34f9105777c457de6810219d
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