1/*
2 * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*
29 * Copyright (c) 1982, 1986, 1988, 1993
30 *	The Regents of the University of California.  All rights reserved.
31 *
32 * Redistribution and use in source and binary forms, with or without
33 * modification, are permitted provided that the following conditions
34 * are met:
35 * 1. Redistributions of source code must retain the above copyright
36 *    notice, this list of conditions and the following disclaimer.
37 * 2. Redistributions in binary form must reproduce the above copyright
38 *    notice, this list of conditions and the following disclaimer in the
39 *    documentation and/or other materials provided with the distribution.
40 * 3. All advertising materials mentioning features or use of this software
41 *    must display the following acknowledgement:
42 *	This product includes software developed by the University of
43 *	California, Berkeley and its contributors.
44 * 4. Neither the name of the University nor the names of its contributors
45 *    may be used to endorse or promote products derived from this software
46 *    without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * $FreeBSD: src/sys/netinet/ip_divert.c,v 1.98 2004/08/17 22:05:54 andre Exp $
61 */
62
63#if !INET
64#error "IPDIVERT requires INET."
65#endif
66
67#include <sys/param.h>
68#include <sys/kernel.h>
69#include <sys/malloc.h>
70#include <sys/mbuf.h>
71#include <sys/socket.h>
72#include <sys/domain.h>
73#include <sys/protosw.h>
74#include <sys/socketvar.h>
75#include <sys/sysctl.h>
76#include <sys/systm.h>
77#include <sys/proc.h>
78
79
80#include <net/if.h>
81#include <net/route.h>
82#include <net/kpi_protocol.h>
83
84#include <netinet/in.h>
85#include <netinet/in_systm.h>
86#include <netinet/ip.h>
87#include <netinet/in_pcb.h>
88#include <netinet/in_var.h>
89#include <netinet/ip_var.h>
90#include <netinet/ip_fw.h>
91#include <netinet/ip_divert.h>
92
93#include <kern/zalloc.h>
94#include <libkern/OSAtomic.h>
95
96/*
97 * Divert sockets
98 */
99
100/*
101 * Allocate enough space to hold a full IP packet
102 */
103#define	DIVSNDQ		(65536 + 100)
104#define	DIVRCVQ		(65536 + 100)
105
106/*
107 * Divert sockets work in conjunction with ipfw, see the divert(4)
108 * manpage for features.
109 * Internally, packets selected by ipfw in ip_input() or ip_output(),
110 * and never diverted before, are passed to the input queue of the
111 * divert socket with a given 'divert_port' number (as specified in
112 * the matching ipfw rule), and they are tagged with a 16 bit cookie
113 * (representing the rule number of the matching ipfw rule), which
114 * is passed to process reading from the socket.
115 *
116 * Packets written to the divert socket are again tagged with a cookie
117 * (usually the same as above) and a destination address.
118 * If the destination address is INADDR_ANY then the packet is
119 * treated as outgoing and sent to ip_output(), otherwise it is
120 * treated as incoming and sent to ip_input().
121 * In both cases, the packet is tagged with the cookie.
122 *
123 * On reinjection, processing in ip_input() and ip_output()
124 * will be exactly the same as for the original packet, except that
125 * ipfw processing will start at the rule number after the one
126 * written in the cookie (so, tagging a packet with a cookie of 0
127 * will cause it to be effectively considered as a standard packet).
128 */
129
130/* Internal variables */
131static struct inpcbhead divcb;
132static struct inpcbinfo divcbinfo;
133
134static u_long	div_sendspace = DIVSNDQ;	/* XXX sysctl ? */
135static u_long	div_recvspace = DIVRCVQ;	/* XXX sysctl ? */
136
137/* Optimization: have this preinitialized */
138static struct sockaddr_in divsrc = { sizeof(divsrc), AF_INET, 0, { 0 }, { 0,0,0,0,0,0,0,0 } };
139
140/* Internal functions */
141static int div_output(struct socket *so,
142		struct mbuf *m, struct sockaddr *addr, struct mbuf *control);
143
144extern int load_ipfw(void);
145/*
146 * Initialize divert connection block queue.
147 */
148void
149div_init(void)
150{
151	struct inpcbinfo *pcbinfo;
152	LIST_INIT(&divcb);
153	divcbinfo.listhead = &divcb;
154	/*
155	 * XXX We don't use the hash list for divert IP, but it's easier
156	 * to allocate a one entry hash list than it is to check all
157	 * over the place for hashbase == NULL.
158	 */
159	divcbinfo.hashbase = hashinit(1, M_PCB, &divcbinfo.hashmask);
160	divcbinfo.porthashbase = hashinit(1, M_PCB, &divcbinfo.porthashmask);
161	divcbinfo.ipi_zone = (void *) zinit(sizeof(struct inpcb),(maxsockets * sizeof(struct inpcb)),
162				   4096, "divzone");
163	pcbinfo = &divcbinfo;
164        /*
165	 * allocate lock group attribute and group for udp pcb mutexes
166	 */
167	pcbinfo->mtx_grp_attr = lck_grp_attr_alloc_init();
168
169	pcbinfo->mtx_grp = lck_grp_alloc_init("divcb", pcbinfo->mtx_grp_attr);
170
171	/*
172	 * allocate the lock attribute for divert pcb mutexes
173	 */
174	pcbinfo->mtx_attr = lck_attr_alloc_init();
175
176	if ((pcbinfo->mtx = lck_rw_alloc_init(pcbinfo->mtx_grp, pcbinfo->mtx_attr)) == NULL)
177		return;	/* pretty much dead if this fails... */
178
179#if IPFIREWALL
180	if (!IPFW_LOADED) {
181		load_ipfw();
182	}
183#endif
184}
185
186/*
187 * IPPROTO_DIVERT is not a real IP protocol; don't allow any packets
188 * with that protocol number to enter the system from the outside.
189 */
190void
191div_input(struct mbuf *m, __unused int off)
192{
193	OSAddAtomic(1, (SInt32*)&ipstat.ips_noproto);
194	m_freem(m);
195}
196
197/*
198 * Divert a packet by passing it up to the divert socket at port 'port'.
199 *
200 * Setup generic address and protocol structures for div_input routine,
201 * then pass them along with mbuf chain.
202 * ###LOCK  called in ip_mutex from ip_output/ip_input
203 */
204void
205divert_packet(struct mbuf *m, int incoming, int port, int rule)
206{
207	struct ip *ip;
208	struct inpcb *inp;
209	struct socket *sa;
210	u_int16_t nport;
211
212	/* Sanity check */
213	KASSERT(port != 0, ("%s: port=0", __FUNCTION__));
214
215	divsrc.sin_port = rule;		/* record matching rule */
216
217	/* Assure header */
218	if (m->m_len < sizeof(struct ip) &&
219	    (m = m_pullup(m, sizeof(struct ip))) == 0) {
220		return;
221	}
222	ip = mtod(m, struct ip *);
223
224	/*
225	 * Record receive interface address, if any.
226	 * But only for incoming packets.
227	 */
228	divsrc.sin_addr.s_addr = 0;
229	if (incoming) {
230		struct ifaddr *ifa;
231
232		/* Sanity check */
233		KASSERT((m->m_flags & M_PKTHDR), ("%s: !PKTHDR", __FUNCTION__));
234
235		/* Find IP address for receive interface */
236		ifnet_lock_shared(m->m_pkthdr.rcvif);
237		TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrhead, ifa_link) {
238			if (ifa->ifa_addr == NULL)
239				continue;
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		ifnet_lock_done(m->m_pkthdr.rcvif);
247	}
248	/*
249	 * Record the incoming interface name whenever we have one.
250	 */
251	bzero(&divsrc.sin_zero, sizeof(divsrc.sin_zero));
252	if (m->m_pkthdr.rcvif) {
253		/*
254		 * Hide the actual interface name in there in the
255		 * sin_zero array. XXX This needs to be moved to a
256		 * different sockaddr type for divert, e.g.
257		 * sockaddr_div with multiple fields like
258		 * sockaddr_dl. Presently we have only 7 bytes
259		 * but that will do for now as most interfaces
260		 * are 4 or less + 2 or less bytes for unit.
261		 * There is probably a faster way of doing this,
262		 * possibly taking it from the sockaddr_dl on the iface.
263		 * This solves the problem of a P2P link and a LAN interface
264		 * having the same address, which can result in the wrong
265		 * interface being assigned to the packet when fed back
266		 * into the divert socket. Theoretically if the daemon saves
267		 * and re-uses the sockaddr_in as suggested in the man pages,
268		 * this iface name will come along for the ride.
269		 * (see div_output for the other half of this.)
270		 */
271		snprintf(divsrc.sin_zero, sizeof(divsrc.sin_zero),
272			"%s%d", m->m_pkthdr.rcvif->if_name,
273			m->m_pkthdr.rcvif->if_unit);
274	}
275
276	/* Put packet on socket queue, if any */
277	sa = NULL;
278	nport = htons((u_int16_t)port);
279	lck_rw_lock_shared(divcbinfo.mtx);
280	LIST_FOREACH(inp, &divcb, inp_list) {
281		if (inp->inp_lport == nport)
282			sa = inp->inp_socket;
283	}
284	if (sa) {
285		int error = 0;
286
287		socket_lock(sa, 1);
288		if (sbappendaddr(&sa->so_rcv, (struct sockaddr *)&divsrc,
289				m, (struct mbuf *)0, &error) != 0)
290			sorwakeup(sa);
291		socket_unlock(sa, 1);
292	} else {
293		m_freem(m);
294		OSAddAtomic(1, (SInt32*)&ipstat.ips_noproto);
295		OSAddAtomic(-1, (SInt32*)&ipstat.ips_delivered);
296        }
297	lck_rw_done(divcbinfo.mtx);
298}
299
300/*
301 * Deliver packet back into the IP processing machinery.
302 *
303 * If no address specified, or address is 0.0.0.0, send to ip_output();
304 * otherwise, send to ip_input() and mark as having been received on
305 * the interface with that address.
306 * ###LOCK  called in inet_proto mutex when from div_send.
307 */
308static int
309div_output(struct socket *so, struct mbuf *m, struct sockaddr *addr,
310	   struct mbuf *control)
311{
312	struct inpcb *const inp = sotoinpcb(so);
313	struct ip *const ip = mtod(m, struct ip *);
314	struct sockaddr_in *sin = (struct sockaddr_in *)addr;
315	int error = 0;
316
317	if (control)
318		m_freem(control);		/* XXX */
319
320	/* Loopback avoidance and state recovery */
321	if (sin) {
322		struct m_tag *mtag;
323		struct divert_tag *dt;
324		int	len = 0;
325		char	*c = sin->sin_zero;
326
327		mtag = m_tag_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_DIVERT,
328				sizeof(struct divert_tag), M_NOWAIT);
329		if (mtag == NULL) {
330			error = ENOBUFS;
331			goto cantsend;
332		}
333		dt = (struct divert_tag *)(mtag+1);
334		dt->info = 0;
335		dt->cookie = sin->sin_port;
336		m_tag_prepend(m, mtag);
337
338		/*
339		 * Find receive interface with the given name or IP address.
340		 * The name is user supplied data so don't trust it's size or
341		 * that it is zero terminated. The name has priority.
342		 * We are presently assuming that the sockaddr_in
343		 * has not been replaced by a sockaddr_div, so we limit it
344		 * to 16 bytes in total. the name is stuffed (if it exists)
345		 * in the sin_zero[] field.
346		 */
347		while (*c++ && (len++ < sizeof(sin->sin_zero)));
348		if ((len > 0) && (len < sizeof(sin->sin_zero)))
349			m->m_pkthdr.rcvif = ifunit(sin->sin_zero);
350	}
351
352	/* Reinject packet into the system as incoming or outgoing */
353	if (!sin || sin->sin_addr.s_addr == 0) {
354		struct ip_out_args ipoa = { IFSCOPE_NONE };
355
356		/*
357		 * Don't allow both user specified and setsockopt options,
358		 * and don't allow packet length sizes that will crash
359		 */
360		if (((ip->ip_hl != (sizeof (*ip) >> 2)) && inp->inp_options) ||
361		     ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) {
362			error = EINVAL;
363			goto cantsend;
364		}
365
366		/* Convert fields to host order for ip_output() */
367		NTOHS(ip->ip_len);
368		NTOHS(ip->ip_off);
369
370		/* Send packet to output processing */
371		OSAddAtomic(1, (SInt32*)&ipstat.ips_rawout);
372		socket_unlock(so, 0);
373#if CONFIG_MACF_NET
374		mac_mbuf_label_associate_inpcb(inp, m);
375#endif
376#if CONFIG_IP_EDGEHOLE
377		ip_edgehole_mbuf_tag(inp, m);
378#endif
379		error = ip_output(m,
380			    inp->inp_options, &inp->inp_route,
381			(so->so_options & SO_DONTROUTE) |
382			IP_ALLOWBROADCAST | IP_RAWOUTPUT | IP_OUTARGS,
383			inp->inp_moptions, &ipoa);
384		socket_lock(so, 0);
385	} else {
386		struct	ifaddr *ifa;
387
388		/* If no luck with the name above. check by IP address.  */
389		if (m->m_pkthdr.rcvif == NULL) {
390			/*
391			 * Make sure there are no distractions
392			 * for ifa_ifwithaddr. Clear the port and the ifname.
393			 * Maybe zap all 8 bytes at once using a 64bit write?
394			 */
395			bzero(sin->sin_zero, sizeof(sin->sin_zero));
396			/* *((u_int64_t *)sin->sin_zero) = 0; */ /* XXX ?? */
397			sin->sin_port = 0;
398			if (!(ifa = ifa_ifwithaddr((struct sockaddr *) sin))) {
399				error = EADDRNOTAVAIL;
400				goto cantsend;
401			}
402			m->m_pkthdr.rcvif = ifa->ifa_ifp;
403			ifafree(ifa);
404		}
405#if CONFIG_MACF_NET
406		mac_mbuf_label_associate_socket(so, m);
407#endif
408		/* Send packet to input processing */
409		proto_inject(PF_INET, m);
410	}
411
412	return error;
413
414cantsend:
415	m_freem(m);
416	return error;
417}
418
419static int
420div_attach(struct socket *so, int proto, struct proc *p)
421{
422	struct inpcb *inp;
423	int error;
424
425
426	inp  = sotoinpcb(so);
427	if (inp)
428		panic("div_attach");
429	if (p && (error = proc_suser(p)) != 0)
430		return error;
431
432	error = soreserve(so, div_sendspace, div_recvspace);
433	if (error)
434		return error;
435	error = in_pcballoc(so, &divcbinfo, p);
436	if (error)
437		return error;
438	inp = (struct inpcb *)so->so_pcb;
439	inp->inp_ip_p = proto;
440	inp->inp_vflag |= INP_IPV4;
441	inp->inp_flags |= INP_HDRINCL;
442	/* The socket is always "connected" because
443	   we always know "where" to send the packet */
444	so->so_state |= SS_ISCONNECTED;
445
446#ifdef MORE_DICVLOCK_DEBUG
447	printf("div_attach: so=%p sopcb=%p lock=%x ref=%x\n",
448			so, so->so_pcb, ((struct inpcb *)so->so_pcb)->inpcb_mtx, so->so_usecount);
449#endif
450	return 0;
451}
452
453static int
454div_detach(struct socket *so)
455{
456	struct inpcb *inp;
457
458#ifdef MORE_DICVLOCK_DEBUG
459	printf("div_detach: so=%p sopcb=%p lock=%x ref=%x\n",
460			so, so->so_pcb, ((struct inpcb *)so->so_pcb)->inpcb_mtx, so->so_usecount);
461#endif
462	inp = sotoinpcb(so);
463	if (inp == 0)
464		panic("div_detach: so=%p null inp\n", so);
465	in_pcbdetach(inp);
466	inp->inp_state = INPCB_STATE_DEAD;
467	return 0;
468}
469
470static int
471div_abort(struct socket *so)
472{
473	soisdisconnected(so);
474	return div_detach(so);
475}
476
477static int
478div_disconnect(struct socket *so)
479{
480	if ((so->so_state & SS_ISCONNECTED) == 0)
481		return ENOTCONN;
482	return div_abort(so);
483}
484
485static int
486div_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
487{
488	struct inpcb *inp;
489	int error;
490
491	inp = sotoinpcb(so);
492	/* in_pcbbind assumes that the socket is a sockaddr_in
493	* and in_pcbbind requires a valid address. Since divert
494	* sockets don't we need to make sure the address is
495	* filled in properly.
496	* XXX -- divert should not be abusing in_pcbind
497	* and should probably have its own family.
498	*/
499	if (nam->sa_family != AF_INET) {
500		error = EAFNOSUPPORT;
501	} else {
502               ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY;
503		error = in_pcbbind(inp, nam, p);
504	}
505	return error;
506}
507
508static int
509div_shutdown(struct socket *so)
510{
511	socantsendmore(so);
512	return 0;
513}
514
515static int
516div_send(struct socket *so, __unused int flags, struct mbuf *m, struct sockaddr *nam,
517	 struct mbuf *control, __unused struct proc *p)
518{
519	/* Packet must have a header (but that's about it) */
520	if (m->m_len < sizeof (struct ip) &&
521	    (m = m_pullup(m, sizeof (struct ip))) == 0) {
522		OSAddAtomic(1, (SInt32*)&ipstat.ips_toosmall);
523		m_freem(m);
524		return EINVAL;
525	}
526
527	/* Send packet */
528	return div_output(so, m, nam, control);
529}
530
531static int
532div_pcblist SYSCTL_HANDLER_ARGS
533{
534	int error, i, n;
535	struct inpcb *inp, **inp_list;
536	inp_gen_t gencnt;
537	struct xinpgen xig;
538
539	/*
540	 * The process of preparing the TCB list is too time-consuming and
541	 * resource-intensive to repeat twice on every request.
542	 */
543	lck_rw_lock_exclusive(divcbinfo.mtx);
544	if (req->oldptr == USER_ADDR_NULL) {
545		n = divcbinfo.ipi_count;
546		req->oldidx = 2 * (sizeof xig)
547			+ (n + n/8) * sizeof(struct xinpcb);
548		lck_rw_done(divcbinfo.mtx);
549		return 0;
550	}
551
552	if (req->newptr != USER_ADDR_NULL) {
553		lck_rw_done(divcbinfo.mtx);
554		return EPERM;
555	}
556
557	/*
558	 * OK, now we're committed to doing something.
559	 */
560	gencnt = divcbinfo.ipi_gencnt;
561	n = divcbinfo.ipi_count;
562
563	bzero(&xig, sizeof(xig));
564	xig.xig_len = sizeof xig;
565	xig.xig_count = n;
566	xig.xig_gen = gencnt;
567	xig.xig_sogen = so_gencnt;
568	error = SYSCTL_OUT(req, &xig, sizeof xig);
569	if (error) {
570		lck_rw_done(divcbinfo.mtx);
571		return error;
572	}
573
574	inp_list = _MALLOC(n * sizeof *inp_list, M_TEMP, M_WAITOK);
575	if (inp_list == 0) {
576		lck_rw_done(divcbinfo.mtx);
577		return ENOMEM;
578	}
579
580	for (inp = LIST_FIRST(divcbinfo.listhead), i = 0; inp && i < n;
581	     inp = LIST_NEXT(inp, inp_list)) {
582#ifdef __APPLE__
583		if (inp->inp_gencnt <= gencnt && inp->inp_state != INPCB_STATE_DEAD)
584#else
585		if (inp->inp_gencnt <= gencnt && !prison_xinpcb(req->p, inp))
586#endif
587			inp_list[i++] = inp;
588	}
589	n = i;
590
591	error = 0;
592	for (i = 0; i < n; i++) {
593		inp = inp_list[i];
594		if (inp->inp_gencnt <= gencnt && inp->inp_state != INPCB_STATE_DEAD) {
595			struct xinpcb xi;
596
597			bzero(&xi, sizeof(xi));
598			xi.xi_len = sizeof xi;
599			/* XXX should avoid extra copy */
600			inpcb_to_compat(inp, &xi.xi_inp);
601			if (inp->inp_socket)
602				sotoxsocket(inp->inp_socket, &xi.xi_socket);
603			error = SYSCTL_OUT(req, &xi, sizeof xi);
604		}
605	}
606	if (!error) {
607		/*
608		 * Give the user an updated idea of our state.
609		 * If the generation differs from what we told
610		 * her before, she knows that something happened
611		 * while we were processing this request, and it
612		 * might be necessary to retry.
613		 */
614		bzero(&xig, sizeof(xig));
615		xig.xig_len = sizeof xig;
616		xig.xig_gen = divcbinfo.ipi_gencnt;
617		xig.xig_sogen = so_gencnt;
618		xig.xig_count = divcbinfo.ipi_count;
619		error = SYSCTL_OUT(req, &xig, sizeof xig);
620	}
621	FREE(inp_list, M_TEMP);
622	lck_rw_done(divcbinfo.mtx);
623	return error;
624}
625
626__private_extern__ int
627div_lock(struct socket *so, int refcount, int lr)
628 {
629	int lr_saved;
630	if (lr == 0)
631		lr_saved = (unsigned int) __builtin_return_address(0);
632	else lr_saved = lr;
633
634#ifdef MORE_DICVLOCK_DEBUG
635	printf("div_lock: so=%p sopcb=%p lock=%x ref=%x lr=%x\n",
636			so,
637			so->so_pcb,
638			so->so_pcb ? ((struct inpcb *)so->so_pcb)->inpcb_mtx : 0,
639			so->so_usecount,
640			lr_saved);
641#endif
642	if (so->so_pcb) {
643		lck_mtx_lock(((struct inpcb *)so->so_pcb)->inpcb_mtx);
644	} else  {
645		panic("div_lock: so=%p NO PCB! lr=%x\n", so, lr_saved);
646		lck_mtx_lock(so->so_proto->pr_domain->dom_mtx);
647	}
648
649	if (so->so_usecount < 0)
650		panic("div_lock: so=%p so_pcb=%p lr=%x ref=%x\n",
651		so, so->so_pcb, lr_saved, so->so_usecount);
652
653	if (refcount)
654		so->so_usecount++;
655	so->lock_lr[so->next_lock_lr] = (u_int32_t)lr_saved;
656	so->next_lock_lr = (so->next_lock_lr+1) % SO_LCKDBG_MAX;
657
658	return (0);
659}
660
661__private_extern__ int
662div_unlock(struct socket *so, int refcount, int lr)
663{
664	int lr_saved;
665	lck_mtx_t * mutex_held;
666	struct inpcb *inp = sotoinpcb(so);
667
668	if (lr == 0)
669		lr_saved = (unsigned int) __builtin_return_address(0);
670	else lr_saved = lr;
671
672
673#ifdef MORE_DICVLOCK_DEBUG
674	printf("div_unlock: so=%p sopcb=%p lock=%x ref=%x lr=%x\n",
675			so,
676			so->so_pcb,
677			so->so_pcb ? ((struct inpcb *)so->so_pcb)->inpcb_mtx : 0,
678			so->so_usecount,
679			lr_saved);
680#endif
681	if (refcount)
682		so->so_usecount--;
683
684	if (so->so_usecount < 0)
685		panic("div_unlock: so=%p usecount=%x\n", so, so->so_usecount);
686	if (so->so_pcb == NULL) {
687		panic("div_unlock: so=%p NO PCB usecount=%x lr=%x\n", so, so->so_usecount, lr_saved);
688		mutex_held = so->so_proto->pr_domain->dom_mtx;
689	} else {
690		mutex_held = ((struct inpcb *)so->so_pcb)->inpcb_mtx;
691	}
692
693	if (so->so_usecount == 0 && (inp->inp_wantcnt == WNT_STOPUSING)) {
694		lck_rw_lock_exclusive(divcbinfo.mtx);
695		in_pcbdispose(inp);
696		lck_rw_done(divcbinfo.mtx);
697		return (0);
698	}
699	lck_mtx_assert(mutex_held, LCK_MTX_ASSERT_OWNED);
700	so->unlock_lr[so->next_unlock_lr] = (u_int32_t) lr_saved;
701	so->next_unlock_lr = (so->next_unlock_lr+1) % SO_LCKDBG_MAX;
702	lck_mtx_unlock(mutex_held);
703	return (0);
704}
705
706__private_extern__ lck_mtx_t *
707div_getlock(struct socket *so, __unused int locktype)
708{
709	struct inpcb *inpcb = (struct inpcb *)so->so_pcb;
710
711	if (so->so_pcb)  {
712		if (so->so_usecount < 0)
713			panic("div_getlock: so=%p usecount=%x\n", so, so->so_usecount);
714		return(inpcb->inpcb_mtx);
715	} else {
716		panic("div_getlock: so=%p NULL so_pcb\n", so);
717		return (so->so_proto->pr_domain->dom_mtx);
718	}
719}
720
721
722struct pr_usrreqs div_usrreqs = {
723	div_abort, pru_accept_notsupp, div_attach, div_bind,
724	pru_connect_notsupp, pru_connect2_notsupp, in_control, div_detach,
725	div_disconnect, pru_listen_notsupp, in_setpeeraddr, pru_rcvd_notsupp,
726	pru_rcvoob_notsupp, div_send, pru_sense_null, div_shutdown,
727	in_setsockaddr, sosend, soreceive, pru_sopoll_notsupp
728};
729
730