xref: /freebsd/sys/netinet/ip_mroute.c (revision 7b71f57f4e514a2ab7308ce4147e14d90e099ad0)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989 Stephen Deering
5  * Copyright (c) 1992, 1993
6  *      The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Stephen Deering of Stanford University.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 /*
37  * IP multicast forwarding procedures
38  *
39  * Written by David Waitzman, BBN Labs, August 1988.
40  * Modified by Steve Deering, Stanford, February 1989.
41  * Modified by Mark J. Steiglitz, Stanford, May, 1991
42  * Modified by Van Jacobson, LBL, January 1993
43  * Modified by Ajit Thyagarajan, PARC, August 1993
44  * Modified by Bill Fenner, PARC, April 1995
45  * Modified by Ahmed Helmy, SGI, June 1996
46  * Modified by George Edmond Eddy (Rusty), ISI, February 1998
47  * Modified by Pavlin Radoslavov, USC/ISI, May 1998, August 1999, October 2000
48  * Modified by Hitoshi Asaeda, WIDE, August 2000
49  * Modified by Pavlin Radoslavov, ICSI, October 2002
50  * Modified by Wojciech Macek, Semihalf, May 2021
51  *
52  * MROUTING Revision: 3.5
53  * and PIM-SMv2 and PIM-DM support, advanced API support,
54  * bandwidth metering and signaling
55  */
56 
57 /*
58  * TODO: Prefix functions with ipmf_.
59  * TODO: Maintain a refcount on if_allmulti() in ifnet or in the protocol
60  * domain attachment (if_afdata) so we can track consumers of that service.
61  * TODO: Deprecate routing socket path for SIOCGETSGCNT and SIOCGETVIFCNT,
62  * move it to socket options.
63  * TODO: Cleanup LSRR removal further.
64  * TODO: Push RSVP stubs into raw_ip.c.
65  * TODO: Use bitstring.h for vif set.
66  * TODO: Fix mrt6_ioctl dangling ref when dynamically loaded.
67  * TODO: Sync ip6_mroute.c with this file.
68  */
69 
70 #include "opt_inet.h"
71 #include "opt_mrouting.h"
72 
73 #define _PIM_VT 1
74 
75 #include <sys/types.h>
76 #include <sys/param.h>
77 #include <sys/kernel.h>
78 #include <sys/stddef.h>
79 #include <sys/condvar.h>
80 #include <sys/eventhandler.h>
81 #include <sys/lock.h>
82 #include <sys/kthread.h>
83 #include <sys/ktr.h>
84 #include <sys/malloc.h>
85 #include <sys/mbuf.h>
86 #include <sys/module.h>
87 #include <sys/priv.h>
88 #include <sys/protosw.h>
89 #include <sys/signalvar.h>
90 #include <sys/socket.h>
91 #include <sys/socketvar.h>
92 #include <sys/sockio.h>
93 #include <sys/sx.h>
94 #include <sys/sysctl.h>
95 #include <sys/syslog.h>
96 #include <sys/systm.h>
97 #include <sys/taskqueue.h>
98 #include <sys/time.h>
99 #include <sys/counter.h>
100 #include <machine/atomic.h>
101 
102 #include <net/if.h>
103 #include <net/if_var.h>
104 #include <net/if_private.h>
105 #include <net/if_types.h>
106 #include <net/netisr.h>
107 #include <net/route.h>
108 #include <net/vnet.h>
109 
110 #include <netinet/in.h>
111 #include <netinet/igmp.h>
112 #include <netinet/in_systm.h>
113 #include <netinet/in_var.h>
114 #include <netinet/ip.h>
115 #include <netinet/ip_encap.h>
116 #include <netinet/ip_mroute.h>
117 #include <netinet/ip_var.h>
118 #include <netinet/ip_options.h>
119 #include <netinet/pim.h>
120 #include <netinet/pim_var.h>
121 #include <netinet/udp.h>
122 
123 #include <machine/in_cksum.h>
124 
125 #ifndef KTR_IPMF
126 #define KTR_IPMF KTR_INET
127 #endif
128 
129 #define		VIFI_INVALID	((vifi_t) -1)
130 
131 static MALLOC_DEFINE(M_MRTABLE, "mroutetbl", "multicast forwarding cache");
132 
133 /*
134  * Locking.  We use two locks: one for the virtual interface table and
135  * one for the forwarding table.  These locks may be nested in which case
136  * the VIF lock must always be taken first.  Note that each lock is used
137  * to cover not only the specific data structure but also related data
138  * structures.
139  */
140 
141 static struct sx __exclusive_cache_line mrouter_teardown;
142 #define	MRW_TEARDOWN_WLOCK()	sx_xlock(&mrouter_teardown)
143 #define	MRW_TEARDOWN_WUNLOCK()	sx_xunlock(&mrouter_teardown)
144 #define	MRW_TEARDOWN_LOCK_INIT()				\
145 	sx_init(&mrouter_teardown, "IPv4 multicast forwarding teardown")
146 #define	MRW_TEARDOWN_LOCK_DESTROY()	sx_destroy(&mrouter_teardown)
147 
148 static struct rwlock mrouter_lock;
149 #define	MRW_RLOCK()		rw_rlock(&mrouter_lock)
150 #define	MRW_WLOCK()		rw_wlock(&mrouter_lock)
151 #define	MRW_RUNLOCK()		rw_runlock(&mrouter_lock)
152 #define	MRW_WUNLOCK()		rw_wunlock(&mrouter_lock)
153 #define	MRW_UNLOCK()		rw_unlock(&mrouter_lock)
154 #define	MRW_LOCK_ASSERT()	rw_assert(&mrouter_lock, RA_LOCKED)
155 #define	MRW_WLOCK_ASSERT()	rw_assert(&mrouter_lock, RA_WLOCKED)
156 #define	MRW_LOCK_TRY_UPGRADE()	rw_try_upgrade(&mrouter_lock)
157 #define	MRW_WOWNED()		rw_wowned(&mrouter_lock)
158 #define	MRW_LOCK_INIT()						\
159 	rw_init(&mrouter_lock, "IPv4 multicast forwarding")
160 #define	MRW_LOCK_DESTROY()	rw_destroy(&mrouter_lock)
161 
162 static int ip_mrouter_cnt;	/* # of vnets with active mrouters */
163 static int ip_mrouter_unloading; /* Allow no more V_ip_mrouter sockets */
164 
165 VNET_PCPUSTAT_DEFINE_STATIC(struct mrtstat, mrtstat);
166 VNET_PCPUSTAT_SYSINIT(mrtstat);
167 VNET_PCPUSTAT_SYSUNINIT(mrtstat);
168 SYSCTL_VNET_PCPUSTAT(_net_inet_ip, OID_AUTO, mrtstat, struct mrtstat,
169     mrtstat, "IPv4 Multicast Forwarding Statistics (struct mrtstat, "
170     "netinet/ip_mroute.h)");
171 
172 VNET_DEFINE_STATIC(u_long, mfchash);
173 #define	V_mfchash		VNET(mfchash)
174 #define	MFCHASH(a, g)							\
175 	((((a).s_addr >> 20) ^ ((a).s_addr >> 10) ^ (a).s_addr ^ \
176 	  ((g).s_addr >> 20) ^ ((g).s_addr >> 10) ^ (g).s_addr) & V_mfchash)
177 #define	MFCHASHSIZE	256
178 
179 static u_long mfchashsize = MFCHASHSIZE;	/* Hash size */
180 SYSCTL_ULONG(_net_inet_ip, OID_AUTO, mfchashsize, CTLFLAG_RDTUN,
181     &mfchashsize, 0, "IPv4 Multicast Forwarding Table hash size");
182 VNET_DEFINE_STATIC(u_char *, nexpire);		/* 0..mfchashsize-1 */
183 #define	V_nexpire		VNET(nexpire)
184 VNET_DEFINE_STATIC(LIST_HEAD(mfchashhdr, mfc)*, mfchashtbl);
185 #define	V_mfchashtbl		VNET(mfchashtbl)
186 VNET_DEFINE_STATIC(struct taskqueue *, task_queue);
187 #define	V_task_queue		VNET(task_queue)
188 VNET_DEFINE_STATIC(struct task, task);
189 #define	V_task		VNET(task)
190 
191 VNET_DEFINE_STATIC(vifi_t, numvifs);
192 #define	V_numvifs		VNET(numvifs)
193 VNET_DEFINE_STATIC(struct vif *, viftable);
194 #define	V_viftable		VNET(viftable)
195 
196 static eventhandler_tag if_detach_event_tag = NULL;
197 
198 VNET_DEFINE_STATIC(struct callout, expire_upcalls_ch);
199 #define	V_expire_upcalls_ch	VNET(expire_upcalls_ch)
200 
201 VNET_DEFINE_STATIC(struct mtx, buf_ring_mtx);
202 #define	V_buf_ring_mtx	VNET(buf_ring_mtx)
203 
204 #define		EXPIRE_TIMEOUT	(hz / 4)	/* 4x / second		*/
205 #define		UPCALL_EXPIRE	6		/* number of timeouts	*/
206 
207 /*
208  * Bandwidth meter variables and constants
209  */
210 static MALLOC_DEFINE(M_BWMETER, "bwmeter", "multicast upcall bw meters");
211 
212 /*
213  * Pending upcalls are stored in a ring which is flushed when
214  * full, or periodically
215  */
216 VNET_DEFINE_STATIC(struct callout, bw_upcalls_ch);
217 #define	V_bw_upcalls_ch		VNET(bw_upcalls_ch)
218 VNET_DEFINE_STATIC(struct buf_ring *, bw_upcalls_ring);
219 #define	V_bw_upcalls_ring    	VNET(bw_upcalls_ring)
220 VNET_DEFINE_STATIC(struct mtx, bw_upcalls_ring_mtx);
221 #define	V_bw_upcalls_ring_mtx    	VNET(bw_upcalls_ring_mtx)
222 
223 #define BW_UPCALLS_PERIOD (hz)		/* periodical flush of bw upcalls */
224 
225 VNET_PCPUSTAT_DEFINE_STATIC(struct pimstat, pimstat);
226 VNET_PCPUSTAT_SYSINIT(pimstat);
227 VNET_PCPUSTAT_SYSUNINIT(pimstat);
228 
229 SYSCTL_NODE(_net_inet, IPPROTO_PIM, pim, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
230     "PIM");
231 SYSCTL_VNET_PCPUSTAT(_net_inet_pim, PIMCTL_STATS, stats, struct pimstat,
232     pimstat, "PIM Statistics (struct pimstat, netinet/pim_var.h)");
233 
234 static u_long	pim_squelch_wholepkt = 0;
235 SYSCTL_ULONG(_net_inet_pim, OID_AUTO, squelch_wholepkt, CTLFLAG_RWTUN,
236     &pim_squelch_wholepkt, 0,
237     "Disable IGMP_WHOLEPKT notifications if rendezvous point is unspecified");
238 
239 static const struct encaptab *pim_encap_cookie;
240 static int pim_encapcheck(const struct mbuf *, int, int, void *);
241 static int pim_input(struct mbuf *, int, int, void *);
242 
243 extern int in_mcast_loop;
244 
245 static const struct encap_config ipv4_encap_cfg = {
246 	.proto = IPPROTO_PIM,
247 	.min_length = sizeof(struct ip) + PIM_MINLEN,
248 	.exact_match = 8,
249 	.check = pim_encapcheck,
250 	.input = pim_input
251 };
252 
253 /*
254  * Note: the PIM Register encapsulation adds the following in front of a
255  * data packet:
256  *
257  * struct pim_encap_hdr {
258  *    struct ip ip;
259  *    struct pim_encap_pimhdr  pim;
260  * }
261  *
262  */
263 
264 struct pim_encap_pimhdr {
265 	struct pim pim;
266 	uint32_t   flags;
267 };
268 #define		PIM_ENCAP_TTL	64
269 
270 static struct ip pim_encap_iphdr = {
271 #if BYTE_ORDER == LITTLE_ENDIAN
272 	sizeof(struct ip) >> 2,
273 	IPVERSION,
274 #else
275 	IPVERSION,
276 	sizeof(struct ip) >> 2,
277 #endif
278 	0,			/* tos */
279 	sizeof(struct ip),	/* total length */
280 	0,			/* id */
281 	0,			/* frag offset */
282 	PIM_ENCAP_TTL,
283 	IPPROTO_PIM,
284 	0,			/* checksum */
285 };
286 
287 static struct pim_encap_pimhdr pim_encap_pimhdr = {
288     {
289 	PIM_MAKE_VT(PIM_VERSION, PIM_REGISTER), /* PIM vers and message type */
290 	0,			/* reserved */
291 	0,			/* checksum */
292     },
293     0				/* flags */
294 };
295 
296 VNET_DEFINE_STATIC(vifi_t, reg_vif_num) = VIFI_INVALID;
297 #define	V_reg_vif_num		VNET(reg_vif_num)
298 VNET_DEFINE_STATIC(struct ifnet *, multicast_register_if);
299 #define	V_multicast_register_if	VNET(multicast_register_if)
300 
301 /*
302  * Private variables.
303  */
304 
305 static u_long	X_ip_mcast_src(int);
306 static int	X_ip_mforward(struct ip *, struct ifnet *, struct mbuf *,
307 		    struct ip_moptions *);
308 static int	X_ip_mrouter_done(void);
309 static int	X_ip_mrouter_get(struct socket *, struct sockopt *);
310 static int	X_ip_mrouter_set(struct socket *, struct sockopt *);
311 static int	X_legal_vif_num(int);
312 static int	X_mrt_ioctl(u_long, caddr_t, int);
313 
314 static int	add_bw_upcall(struct bw_upcall *);
315 static int	add_mfc(struct mfcctl2 *);
316 static int	add_vif(struct vifctl *);
317 static void	bw_meter_prepare_upcall(struct bw_meter *, struct timeval *);
318 static void	bw_meter_geq_receive_packet(struct bw_meter *, int,
319 		    struct timeval *);
320 static void	bw_upcalls_send(void);
321 static int	del_bw_upcall(struct bw_upcall *);
322 static int	del_mfc(struct mfcctl2 *);
323 static int	del_vif(vifi_t);
324 static int	del_vif_locked(vifi_t, struct ifnet **, struct ifnet **);
325 static void	expire_bw_upcalls_send(void *);
326 static void	expire_mfc(struct mfc *);
327 static void	expire_upcalls(void *);
328 static void	free_bw_list(struct bw_meter *);
329 static int	get_sg_cnt(struct sioc_sg_req *);
330 static int	get_vif_cnt(struct sioc_vif_req *);
331 static void	if_detached_event(void *, struct ifnet *);
332 static int	ip_mdq(struct mbuf *, struct ifnet *, struct mfc *, vifi_t);
333 static int	ip_mrouter_init(struct socket *, int);
334 static __inline struct mfc *
335 		mfc_find(struct in_addr *, struct in_addr *);
336 static void	phyint_send(struct ip *, struct vif *, struct mbuf *);
337 static struct mbuf *
338 		pim_register_prepare(struct ip *, struct mbuf *);
339 static int	pim_register_send(struct ip *, struct vif *,
340 		    struct mbuf *, struct mfc *);
341 static int	pim_register_send_rp(struct ip *, struct vif *,
342 		    struct mbuf *, struct mfc *);
343 static int	pim_register_send_upcall(struct ip *, struct vif *,
344 		    struct mbuf *, struct mfc *);
345 static void	send_packet(struct vif *, struct mbuf *);
346 static int	set_api_config(uint32_t *);
347 static int	set_assert(int);
348 static int	socket_send(struct socket *, struct mbuf *,
349 		    struct sockaddr_in *);
350 
351 /*
352  * Kernel multicast forwarding API capabilities and setup.
353  * If more API capabilities are added to the kernel, they should be
354  * recorded in `mrt_api_support'.
355  */
356 #define MRT_API_VERSION		0x0305
357 
358 static const int mrt_api_version = MRT_API_VERSION;
359 static const uint32_t mrt_api_support = (MRT_MFC_FLAGS_DISABLE_WRONGVIF |
360 					 MRT_MFC_FLAGS_BORDER_VIF |
361 					 MRT_MFC_RP |
362 					 MRT_MFC_BW_UPCALL);
363 VNET_DEFINE_STATIC(uint32_t, mrt_api_config);
364 #define	V_mrt_api_config	VNET(mrt_api_config)
365 VNET_DEFINE_STATIC(int, pim_assert_enabled);
366 #define	V_pim_assert_enabled	VNET(pim_assert_enabled)
367 static struct timeval pim_assert_interval = { 3, 0 };	/* Rate limit */
368 
369 /*
370  * Find a route for a given origin IP address and multicast group address.
371  * Statistics must be updated by the caller.
372  */
373 static __inline struct mfc *
mfc_find(struct in_addr * o,struct in_addr * g)374 mfc_find(struct in_addr *o, struct in_addr *g)
375 {
376 	struct mfc *rt;
377 
378 	/*
379 	 * Might be called both RLOCK and WLOCK.
380 	 * Check if any, it's caller responsibility
381 	 * to choose correct option.
382 	 */
383 	MRW_LOCK_ASSERT();
384 
385 	LIST_FOREACH(rt, &V_mfchashtbl[MFCHASH(*o, *g)], mfc_hash) {
386 		if (in_hosteq(rt->mfc_origin, *o) &&
387 		    in_hosteq(rt->mfc_mcastgrp, *g) &&
388 		    buf_ring_empty(rt->mfc_stall_ring))
389 			break;
390 	}
391 
392 	return (rt);
393 }
394 
395 static __inline struct mfc *
mfc_alloc(void)396 mfc_alloc(void)
397 {
398 	struct mfc *rt;
399 	rt = malloc(sizeof(*rt), M_MRTABLE, M_NOWAIT | M_ZERO);
400 	if (rt == NULL)
401 		return rt;
402 
403 	rt->mfc_stall_ring = buf_ring_alloc(MAX_UPQ, M_MRTABLE,
404 	    M_NOWAIT, &V_buf_ring_mtx);
405 	if (rt->mfc_stall_ring == NULL) {
406 		free(rt, M_MRTABLE);
407 		return NULL;
408 	}
409 
410 	return rt;
411 }
412 
413 /*
414  * Handle MRT setsockopt commands to modify the multicast forwarding tables.
415  */
416 static int
X_ip_mrouter_set(struct socket * so,struct sockopt * sopt)417 X_ip_mrouter_set(struct socket *so, struct sockopt *sopt)
418 {
419 	int error, optval;
420 	vifi_t vifi;
421 	struct vifctl vifc;
422 	struct mfcctl2 mfc;
423 	struct bw_upcall bw_upcall;
424 	uint32_t i;
425 
426 	if (so != V_ip_mrouter && sopt->sopt_name != MRT_INIT)
427 		return EPERM;
428 
429 	error = 0;
430 	switch (sopt->sopt_name) {
431 	case MRT_INIT:
432 		error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval);
433 		if (error)
434 			break;
435 		error = ip_mrouter_init(so, optval);
436 		break;
437 	case MRT_DONE:
438 		error = ip_mrouter_done();
439 		break;
440 	case MRT_ADD_VIF:
441 		error = sooptcopyin(sopt, &vifc, sizeof vifc, sizeof vifc);
442 		if (error)
443 			break;
444 		error = add_vif(&vifc);
445 		break;
446 	case MRT_DEL_VIF:
447 		error = sooptcopyin(sopt, &vifi, sizeof vifi, sizeof vifi);
448 		if (error)
449 			break;
450 		error = del_vif(vifi);
451 		break;
452 	case MRT_ADD_MFC:
453 	case MRT_DEL_MFC:
454 		/*
455 		 * select data size depending on API version.
456 		 */
457 		if (sopt->sopt_name == MRT_ADD_MFC &&
458 		    V_mrt_api_config & MRT_API_FLAGS_ALL) {
459 			error = sooptcopyin(sopt, &mfc, sizeof(struct mfcctl2),
460 			    sizeof(struct mfcctl2));
461 		} else {
462 			error = sooptcopyin(sopt, &mfc, sizeof(struct mfcctl),
463 			    sizeof(struct mfcctl));
464 			bzero((caddr_t)&mfc + sizeof(struct mfcctl),
465 			    sizeof(mfc) - sizeof(struct mfcctl));
466 		}
467 		if (error)
468 			break;
469 		if (sopt->sopt_name == MRT_ADD_MFC)
470 			error = add_mfc(&mfc);
471 		else
472 			error = del_mfc(&mfc);
473 		break;
474 
475 	case MRT_ASSERT:
476 		error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval);
477 		if (error)
478 			break;
479 		set_assert(optval);
480 		break;
481 
482 	case MRT_API_CONFIG:
483 		error = sooptcopyin(sopt, &i, sizeof i, sizeof i);
484 		if (!error)
485 			error = set_api_config(&i);
486 		if (!error)
487 			error = sooptcopyout(sopt, &i, sizeof i);
488 		break;
489 
490 	case MRT_ADD_BW_UPCALL:
491 	case MRT_DEL_BW_UPCALL:
492 		error = sooptcopyin(sopt, &bw_upcall, sizeof bw_upcall,
493 		    sizeof bw_upcall);
494 		if (error)
495 			break;
496 		if (sopt->sopt_name == MRT_ADD_BW_UPCALL)
497 			error = add_bw_upcall(&bw_upcall);
498 		else
499 			error = del_bw_upcall(&bw_upcall);
500 		break;
501 
502 	default:
503 		error = EOPNOTSUPP;
504 		break;
505 	}
506 	return error;
507 }
508 
509 /*
510  * Handle MRT getsockopt commands
511  */
512 static int
X_ip_mrouter_get(struct socket * so,struct sockopt * sopt)513 X_ip_mrouter_get(struct socket *so, struct sockopt *sopt)
514 {
515 	int error;
516 
517 	switch (sopt->sopt_name) {
518 	case MRT_VERSION:
519 		error = sooptcopyout(sopt, &mrt_api_version,
520 		    sizeof mrt_api_version);
521 		break;
522 	case MRT_ASSERT:
523 		error = sooptcopyout(sopt, &V_pim_assert_enabled,
524 		    sizeof V_pim_assert_enabled);
525 		break;
526 	case MRT_API_SUPPORT:
527 		error = sooptcopyout(sopt, &mrt_api_support,
528 		    sizeof mrt_api_support);
529 		break;
530 	case MRT_API_CONFIG:
531 		error = sooptcopyout(sopt, &V_mrt_api_config,
532 		    sizeof V_mrt_api_config);
533 		break;
534 	default:
535 		error = EOPNOTSUPP;
536 		break;
537 	}
538 	return error;
539 }
540 
541 /*
542  * Handle ioctl commands to obtain information from the cache
543  */
544 static int
X_mrt_ioctl(u_long cmd,caddr_t data,int fibnum __unused)545 X_mrt_ioctl(u_long cmd, caddr_t data, int fibnum __unused)
546 {
547 	int error;
548 
549 	/*
550 	 * Currently the only function calling this ioctl routine is rtioctl_fib().
551 	 * Typically, only root can create the raw socket in order to execute
552 	 * this ioctl method, however the request might be coming from a prison
553 	 */
554 	error = priv_check(curthread, PRIV_NETINET_MROUTE);
555 	if (error)
556 		return (error);
557 	switch (cmd) {
558 	case (SIOCGETVIFCNT):
559 		error = get_vif_cnt((struct sioc_vif_req *)data);
560 		break;
561 
562 	case (SIOCGETSGCNT):
563 		error = get_sg_cnt((struct sioc_sg_req *)data);
564 		break;
565 
566 	default:
567 		error = EINVAL;
568 		break;
569 	}
570 	return error;
571 }
572 
573 /*
574  * returns the packet, byte, rpf-failure count for the source group provided
575  */
576 static int
get_sg_cnt(struct sioc_sg_req * req)577 get_sg_cnt(struct sioc_sg_req *req)
578 {
579 	struct mfc *rt;
580 
581 	MRW_RLOCK();
582 	rt = mfc_find(&req->src, &req->grp);
583 	if (rt == NULL) {
584 		MRW_RUNLOCK();
585 		req->pktcnt = req->bytecnt = req->wrong_if = 0xffffffff;
586 		return EADDRNOTAVAIL;
587 	}
588 	req->pktcnt = rt->mfc_pkt_cnt;
589 	req->bytecnt = rt->mfc_byte_cnt;
590 	req->wrong_if = rt->mfc_wrong_if;
591 	MRW_RUNLOCK();
592 	return 0;
593 }
594 
595 /*
596  * returns the input and output packet and byte counts on the vif provided
597  */
598 static int
get_vif_cnt(struct sioc_vif_req * req)599 get_vif_cnt(struct sioc_vif_req *req)
600 {
601 	vifi_t vifi = req->vifi;
602 
603 	MRW_RLOCK();
604 	if (vifi >= V_numvifs) {
605 		MRW_RUNLOCK();
606 		return EINVAL;
607 	}
608 
609 	mtx_lock_spin(&V_viftable[vifi].v_spin);
610 	req->icount = V_viftable[vifi].v_pkt_in;
611 	req->ocount = V_viftable[vifi].v_pkt_out;
612 	req->ibytes = V_viftable[vifi].v_bytes_in;
613 	req->obytes = V_viftable[vifi].v_bytes_out;
614 	mtx_unlock_spin(&V_viftable[vifi].v_spin);
615 	MRW_RUNLOCK();
616 
617 	return 0;
618 }
619 
620 static void
if_detached_event(void * arg __unused,struct ifnet * ifp)621 if_detached_event(void *arg __unused, struct ifnet *ifp)
622 {
623 	vifi_t vifi;
624 	u_long i, vifi_cnt = 0;
625 	struct ifnet *free_ptr, *multi_leave;
626 
627 	MRW_WLOCK();
628 
629 	if (V_ip_mrouter == NULL) {
630 		MRW_WUNLOCK();
631 		return;
632 	}
633 
634 	/*
635 	 * Tear down multicast forwarder state associated with this ifnet.
636 	 * 1. Walk the vif list, matching vifs against this ifnet.
637 	 * 2. Walk the multicast forwarding cache (mfc) looking for
638 	 *    inner matches with this vif's index.
639 	 * 3. Expire any matching multicast forwarding cache entries.
640 	 * 4. Free vif state. This should disable ALLMULTI on the interface.
641 	 */
642 restart:
643 	for (vifi = 0; vifi < V_numvifs; vifi++) {
644 		if (V_viftable[vifi].v_ifp != ifp)
645 			continue;
646 		for (i = 0; i < mfchashsize; i++) {
647 			struct mfc *rt, *nrt;
648 
649 			LIST_FOREACH_SAFE(rt, &V_mfchashtbl[i], mfc_hash, nrt) {
650 				if (rt->mfc_parent == vifi) {
651 					expire_mfc(rt);
652 				}
653 			}
654 		}
655 		del_vif_locked(vifi, &multi_leave, &free_ptr);
656 		if (free_ptr != NULL)
657 			vifi_cnt++;
658 		if (multi_leave) {
659 			MRW_WUNLOCK();
660 			if_allmulti(multi_leave, 0);
661 			MRW_WLOCK();
662 			goto restart;
663 		}
664 	}
665 
666 	MRW_WUNLOCK();
667 
668 	/*
669 	 * Free IFP. We don't have to use free_ptr here as it is the same
670 	 * that ifp. Perform free as many times as required in case
671 	 * refcount is greater than 1.
672 	 */
673 	for (i = 0; i < vifi_cnt; i++)
674 		if_free(ifp);
675 }
676 
677 static void
ip_mrouter_upcall_thread(void * arg,int pending __unused)678 ip_mrouter_upcall_thread(void *arg, int pending __unused)
679 {
680 	CURVNET_SET((struct vnet *) arg);
681 
682 	MRW_WLOCK();
683 	bw_upcalls_send();
684 	MRW_WUNLOCK();
685 
686 	CURVNET_RESTORE();
687 }
688 
689 /*
690  * Enable multicast forwarding.
691  */
692 static int
ip_mrouter_init(struct socket * so,int version)693 ip_mrouter_init(struct socket *so, int version)
694 {
695 
696 	CTR2(KTR_IPMF, "%s: so %p", __func__, so);
697 
698 	if (version != 1)
699 		return ENOPROTOOPT;
700 
701 	MRW_TEARDOWN_WLOCK();
702 	MRW_WLOCK();
703 
704 	if (ip_mrouter_unloading) {
705 		MRW_WUNLOCK();
706 		MRW_TEARDOWN_WUNLOCK();
707 		return ENOPROTOOPT;
708 	}
709 
710 	if (V_ip_mrouter != NULL) {
711 		MRW_WUNLOCK();
712 		MRW_TEARDOWN_WUNLOCK();
713 		return EADDRINUSE;
714 	}
715 
716 	V_mfchashtbl = hashinit_flags(mfchashsize, M_MRTABLE, &V_mfchash,
717 	    HASH_NOWAIT);
718 	if (V_mfchashtbl == NULL) {
719 		MRW_WUNLOCK();
720 		MRW_TEARDOWN_WUNLOCK();
721 		return (ENOMEM);
722 	}
723 
724 	/* Create upcall ring */
725 	mtx_init(&V_bw_upcalls_ring_mtx, "mroute upcall buf_ring mtx", NULL, MTX_DEF);
726 	V_bw_upcalls_ring = buf_ring_alloc(BW_UPCALLS_MAX, M_MRTABLE,
727 	    M_NOWAIT, &V_bw_upcalls_ring_mtx);
728 	if (!V_bw_upcalls_ring) {
729 		MRW_WUNLOCK();
730 		MRW_TEARDOWN_WUNLOCK();
731 		return (ENOMEM);
732 	}
733 
734 	TASK_INIT(&V_task, 0, ip_mrouter_upcall_thread, curvnet);
735 	taskqueue_cancel(V_task_queue, &V_task, NULL);
736 	taskqueue_unblock(V_task_queue);
737 
738 	callout_reset(&V_expire_upcalls_ch, EXPIRE_TIMEOUT, expire_upcalls,
739 	    curvnet);
740 	callout_reset(&V_bw_upcalls_ch, BW_UPCALLS_PERIOD, expire_bw_upcalls_send,
741 	    curvnet);
742 
743 	V_ip_mrouter = so;
744 	atomic_add_int(&ip_mrouter_cnt, 1);
745 
746 	/* This is a mutex required by buf_ring init, but not used internally */
747 	mtx_init(&V_buf_ring_mtx, "mroute buf_ring mtx", NULL, MTX_DEF);
748 
749 	MRW_WUNLOCK();
750 	MRW_TEARDOWN_WUNLOCK();
751 
752 	CTR1(KTR_IPMF, "%s: done", __func__);
753 
754 	return 0;
755 }
756 
757 /*
758  * Disable multicast forwarding.
759  */
760 static int
X_ip_mrouter_done(void)761 X_ip_mrouter_done(void)
762 {
763 	struct ifnet **ifps;
764 	int nifp;
765 	u_long i;
766 	vifi_t vifi;
767 	struct bw_upcall *bu;
768 
769 	MRW_TEARDOWN_WLOCK();
770 
771 	if (V_ip_mrouter == NULL) {
772 		MRW_TEARDOWN_WUNLOCK();
773 		return (EINVAL);
774 	}
775 
776 	/*
777 	 * Detach/disable hooks to the reset of the system.
778 	 */
779 	V_ip_mrouter = NULL;
780 	atomic_subtract_int(&ip_mrouter_cnt, 1);
781 	V_mrt_api_config = 0;
782 
783 	/*
784 	 * Wait for all epoch sections to complete to ensure
785 	 * V_ip_mrouter = NULL is visible to others.
786 	 */
787 	NET_EPOCH_WAIT();
788 
789 	/* Stop and drain task queue */
790 	taskqueue_block(V_task_queue);
791 	while (taskqueue_cancel(V_task_queue, &V_task, NULL)) {
792 		taskqueue_drain(V_task_queue, &V_task);
793 	}
794 
795 	ifps = malloc(MAXVIFS * sizeof(*ifps), M_TEMP, M_WAITOK);
796 
797 	MRW_WLOCK();
798 	taskqueue_cancel(V_task_queue, &V_task, NULL);
799 
800 	/* Destroy upcall ring */
801 	while ((bu = buf_ring_dequeue_mc(V_bw_upcalls_ring)) != NULL) {
802 		free(bu, M_MRTABLE);
803 	}
804 	buf_ring_free(V_bw_upcalls_ring, M_MRTABLE);
805 	mtx_destroy(&V_bw_upcalls_ring_mtx);
806 
807 	/*
808 	 * For each phyint in use, prepare to disable promiscuous reception
809 	 * of all IP multicasts.  Defer the actual call until the lock is released;
810 	 * just record the list of interfaces while locked.  Some interfaces use
811 	 * sx locks in their ioctl routines, which is not allowed while holding
812 	 * a non-sleepable lock.
813 	 */
814 	KASSERT(V_numvifs <= MAXVIFS, ("More vifs than possible"));
815 	for (vifi = 0, nifp = 0; vifi < V_numvifs; vifi++) {
816 		if (!in_nullhost(V_viftable[vifi].v_lcl_addr) &&
817 		    !(V_viftable[vifi].v_flags & (VIFF_TUNNEL | VIFF_REGISTER))) {
818 			ifps[nifp++] = V_viftable[vifi].v_ifp;
819 		}
820 	}
821 	bzero((caddr_t)V_viftable, sizeof(*V_viftable) * MAXVIFS);
822 	V_numvifs = 0;
823 	V_pim_assert_enabled = 0;
824 
825 	callout_stop(&V_expire_upcalls_ch);
826 	callout_stop(&V_bw_upcalls_ch);
827 
828 	/*
829 	 * Free all multicast forwarding cache entries.
830 	 * Do not use hashdestroy(), as we must perform other cleanup.
831 	 */
832 	for (i = 0; i < mfchashsize; i++) {
833 		struct mfc *rt, *nrt;
834 
835 		LIST_FOREACH_SAFE(rt, &V_mfchashtbl[i], mfc_hash, nrt) {
836 			expire_mfc(rt);
837 		}
838 	}
839 	free(V_mfchashtbl, M_MRTABLE);
840 	V_mfchashtbl = NULL;
841 
842 	bzero(V_nexpire, sizeof(V_nexpire[0]) * mfchashsize);
843 
844 	V_reg_vif_num = VIFI_INVALID;
845 
846 	mtx_destroy(&V_buf_ring_mtx);
847 
848 	MRW_WUNLOCK();
849 	MRW_TEARDOWN_WUNLOCK();
850 
851 	/*
852 	 * Now drop our claim on promiscuous multicast on the interfaces recorded
853 	 * above.  This is safe to do now because ALLMULTI is reference counted.
854 	 */
855 	for (vifi = 0; vifi < nifp; vifi++)
856 		if_allmulti(ifps[vifi], 0);
857 	free(ifps, M_TEMP);
858 
859 	CTR1(KTR_IPMF, "%s: done", __func__);
860 
861 	return 0;
862 }
863 
864 /*
865  * Set PIM assert processing global
866  */
867 static int
set_assert(int i)868 set_assert(int i)
869 {
870 	if ((i != 1) && (i != 0))
871 		return EINVAL;
872 
873 	V_pim_assert_enabled = i;
874 
875 	return 0;
876 }
877 
878 /*
879  * Configure API capabilities
880  */
881 int
set_api_config(uint32_t * apival)882 set_api_config(uint32_t *apival)
883 {
884 	u_long i;
885 
886 	/*
887 	 * We can set the API capabilities only if it is the first operation
888 	 * after MRT_INIT. I.e.:
889 	 *  - there are no vifs installed
890 	 *  - pim_assert is not enabled
891 	 *  - the MFC table is empty
892 	 */
893 	if (V_numvifs > 0) {
894 		*apival = 0;
895 		return EPERM;
896 	}
897 	if (V_pim_assert_enabled) {
898 		*apival = 0;
899 		return EPERM;
900 	}
901 
902 	MRW_RLOCK();
903 
904 	for (i = 0; i < mfchashsize; i++) {
905 		if (LIST_FIRST(&V_mfchashtbl[i]) != NULL) {
906 			MRW_RUNLOCK();
907 			*apival = 0;
908 			return EPERM;
909 		}
910 	}
911 
912 	MRW_RUNLOCK();
913 
914 	V_mrt_api_config = *apival & mrt_api_support;
915 	*apival = V_mrt_api_config;
916 
917 	return 0;
918 }
919 
920 /*
921  * Add a vif to the vif table
922  */
923 static int
add_vif(struct vifctl * vifcp)924 add_vif(struct vifctl *vifcp)
925 {
926 	struct vif *vifp = V_viftable + vifcp->vifc_vifi;
927 	struct sockaddr_in sin = {sizeof sin, AF_INET};
928 	struct ifaddr *ifa;
929 	struct ifnet *ifp;
930 	int error;
931 
932 	if (vifcp->vifc_vifi >= MAXVIFS)
933 		return EINVAL;
934 	/* rate limiting is no longer supported by this code */
935 	if (vifcp->vifc_rate_limit != 0) {
936 		log(LOG_ERR, "rate limiting is no longer supported\n");
937 		return EINVAL;
938 	}
939 
940 	if (in_nullhost(vifcp->vifc_lcl_addr))
941 		return EADDRNOTAVAIL;
942 
943 	/* Find the interface with an address in AF_INET family */
944 	if (vifcp->vifc_flags & VIFF_REGISTER) {
945 		/*
946 		 * XXX: Because VIFF_REGISTER does not really need a valid
947 		 * local interface (e.g. it could be 127.0.0.2), we don't
948 		 * check its address.
949 		 */
950 		ifp = NULL;
951 	} else {
952 		struct epoch_tracker et;
953 
954 		sin.sin_addr = vifcp->vifc_lcl_addr;
955 		NET_EPOCH_ENTER(et);
956 		ifa = ifa_ifwithaddr((struct sockaddr *)&sin);
957 		if (ifa == NULL) {
958 			NET_EPOCH_EXIT(et);
959 			return EADDRNOTAVAIL;
960 		}
961 		ifp = ifa->ifa_ifp;
962 		/* XXX FIXME we need to take a ref on ifp and cleanup properly! */
963 		NET_EPOCH_EXIT(et);
964 	}
965 
966 	if ((vifcp->vifc_flags & VIFF_TUNNEL) != 0) {
967 		CTR1(KTR_IPMF, "%s: tunnels are no longer supported", __func__);
968 		return EOPNOTSUPP;
969 	} else if (vifcp->vifc_flags & VIFF_REGISTER) {
970 		ifp = V_multicast_register_if = if_alloc(IFT_LOOP);
971 		CTR2(KTR_IPMF, "%s: add register vif for ifp %p", __func__, ifp);
972 		if (V_reg_vif_num == VIFI_INVALID) {
973 			if_initname(V_multicast_register_if, "register_vif", 0);
974 			V_reg_vif_num = vifcp->vifc_vifi;
975 		}
976 	} else {		/* Make sure the interface supports multicast */
977 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
978 			return EOPNOTSUPP;
979 
980 		/* Enable promiscuous reception of all IP multicasts from the if */
981 		error = if_allmulti(ifp, 1);
982 		if (error)
983 			return error;
984 	}
985 
986 	MRW_WLOCK();
987 
988 	if (!in_nullhost(vifp->v_lcl_addr)) {
989 		if (ifp)
990 			V_multicast_register_if = NULL;
991 		MRW_WUNLOCK();
992 		if (ifp)
993 			if_free(ifp);
994 		return EADDRINUSE;
995 	}
996 
997 	vifp->v_flags     = vifcp->vifc_flags;
998 	vifp->v_threshold = vifcp->vifc_threshold;
999 	vifp->v_lcl_addr  = vifcp->vifc_lcl_addr;
1000 	vifp->v_rmt_addr  = vifcp->vifc_rmt_addr;
1001 	vifp->v_ifp       = ifp;
1002 	/* initialize per vif pkt counters */
1003 	vifp->v_pkt_in    = 0;
1004 	vifp->v_pkt_out   = 0;
1005 	vifp->v_bytes_in  = 0;
1006 	vifp->v_bytes_out = 0;
1007 	sprintf(vifp->v_spin_name, "BM[%d] spin", vifcp->vifc_vifi);
1008 	mtx_init(&vifp->v_spin, vifp->v_spin_name, NULL, MTX_SPIN);
1009 
1010 	/* Adjust numvifs up if the vifi is higher than numvifs */
1011 	if (V_numvifs <= vifcp->vifc_vifi)
1012 		V_numvifs = vifcp->vifc_vifi + 1;
1013 
1014 	MRW_WUNLOCK();
1015 
1016 	CTR4(KTR_IPMF, "%s: add vif %d laddr 0x%08x thresh %x", __func__,
1017 	    (int)vifcp->vifc_vifi, ntohl(vifcp->vifc_lcl_addr.s_addr),
1018 	    (int)vifcp->vifc_threshold);
1019 
1020 	return 0;
1021 }
1022 
1023 /*
1024  * Delete a vif from the vif table
1025  */
1026 static int
del_vif_locked(vifi_t vifi,struct ifnet ** ifp_multi_leave,struct ifnet ** ifp_free)1027 del_vif_locked(vifi_t vifi, struct ifnet **ifp_multi_leave, struct ifnet **ifp_free)
1028 {
1029 	struct vif *vifp;
1030 
1031 	*ifp_free = NULL;
1032 	*ifp_multi_leave = NULL;
1033 
1034 	MRW_WLOCK_ASSERT();
1035 
1036 	if (vifi >= V_numvifs) {
1037 		return EINVAL;
1038 	}
1039 	vifp = &V_viftable[vifi];
1040 	if (in_nullhost(vifp->v_lcl_addr)) {
1041 		return EADDRNOTAVAIL;
1042 	}
1043 
1044 	if (!(vifp->v_flags & (VIFF_TUNNEL | VIFF_REGISTER)))
1045 		*ifp_multi_leave = vifp->v_ifp;
1046 
1047 	if (vifp->v_flags & VIFF_REGISTER) {
1048 		V_reg_vif_num = VIFI_INVALID;
1049 		if (vifp->v_ifp) {
1050 			if (vifp->v_ifp == V_multicast_register_if)
1051 				V_multicast_register_if = NULL;
1052 			*ifp_free = vifp->v_ifp;
1053 		}
1054 	}
1055 
1056 	mtx_destroy(&vifp->v_spin);
1057 
1058 	bzero((caddr_t)vifp, sizeof (*vifp));
1059 
1060 	CTR2(KTR_IPMF, "%s: delete vif %d", __func__, (int)vifi);
1061 
1062 	/* Adjust numvifs down */
1063 	for (vifi = V_numvifs; vifi > 0; vifi--)
1064 		if (!in_nullhost(V_viftable[vifi-1].v_lcl_addr))
1065 			break;
1066 	V_numvifs = vifi;
1067 
1068 	return 0;
1069 }
1070 
1071 static int
del_vif(vifi_t vifi)1072 del_vif(vifi_t vifi)
1073 {
1074 	int cc;
1075 	struct ifnet *free_ptr, *multi_leave;
1076 
1077 	MRW_WLOCK();
1078 	cc = del_vif_locked(vifi, &multi_leave, &free_ptr);
1079 	MRW_WUNLOCK();
1080 
1081 	if (multi_leave)
1082 		if_allmulti(multi_leave, 0);
1083 	if (free_ptr) {
1084 		if_free(free_ptr);
1085 	}
1086 
1087 	return cc;
1088 }
1089 
1090 /*
1091  * update an mfc entry without resetting counters and S,G addresses.
1092  */
1093 static void
update_mfc_params(struct mfc * rt,struct mfcctl2 * mfccp)1094 update_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp)
1095 {
1096 	int i;
1097 
1098 	rt->mfc_parent = mfccp->mfcc_parent;
1099 	for (i = 0; i < V_numvifs; i++) {
1100 		rt->mfc_ttls[i] = mfccp->mfcc_ttls[i];
1101 		rt->mfc_flags[i] = mfccp->mfcc_flags[i] & V_mrt_api_config &
1102 			MRT_MFC_FLAGS_ALL;
1103 	}
1104 	/* set the RP address */
1105 	if (V_mrt_api_config & MRT_MFC_RP)
1106 		rt->mfc_rp = mfccp->mfcc_rp;
1107 	else
1108 		rt->mfc_rp.s_addr = INADDR_ANY;
1109 }
1110 
1111 /*
1112  * fully initialize an mfc entry from the parameter.
1113  */
1114 static void
init_mfc_params(struct mfc * rt,struct mfcctl2 * mfccp)1115 init_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp)
1116 {
1117 	rt->mfc_origin     = mfccp->mfcc_origin;
1118 	rt->mfc_mcastgrp   = mfccp->mfcc_mcastgrp;
1119 
1120 	update_mfc_params(rt, mfccp);
1121 
1122 	/* initialize pkt counters per src-grp */
1123 	rt->mfc_pkt_cnt    = 0;
1124 	rt->mfc_byte_cnt   = 0;
1125 	rt->mfc_wrong_if   = 0;
1126 	timevalclear(&rt->mfc_last_assert);
1127 }
1128 
1129 static void
expire_mfc(struct mfc * rt)1130 expire_mfc(struct mfc *rt)
1131 {
1132 	struct rtdetq *rte;
1133 
1134 	MRW_WLOCK_ASSERT();
1135 
1136 	free_bw_list(rt->mfc_bw_meter_leq);
1137 	free_bw_list(rt->mfc_bw_meter_geq);
1138 
1139 	while (!buf_ring_empty(rt->mfc_stall_ring)) {
1140 		rte = buf_ring_dequeue_mc(rt->mfc_stall_ring);
1141 		if (rte) {
1142 			m_freem(rte->m);
1143 			free(rte, M_MRTABLE);
1144 		}
1145 	}
1146 	buf_ring_free(rt->mfc_stall_ring, M_MRTABLE);
1147 
1148 	LIST_REMOVE(rt, mfc_hash);
1149 	free(rt, M_MRTABLE);
1150 }
1151 
1152 /*
1153  * Add an mfc entry
1154  */
1155 static int
add_mfc(struct mfcctl2 * mfccp)1156 add_mfc(struct mfcctl2 *mfccp)
1157 {
1158 	struct mfc *rt;
1159 	struct rtdetq *rte;
1160 	u_long hash = 0;
1161 	u_short nstl;
1162 	struct epoch_tracker et;
1163 
1164 	MRW_WLOCK();
1165 	rt = mfc_find(&mfccp->mfcc_origin, &mfccp->mfcc_mcastgrp);
1166 
1167 	/* If an entry already exists, just update the fields */
1168 	if (rt) {
1169 		CTR4(KTR_IPMF, "%s: update mfc orig 0x%08x group %lx parent %x",
1170 		    __func__, ntohl(mfccp->mfcc_origin.s_addr),
1171 		    (u_long)ntohl(mfccp->mfcc_mcastgrp.s_addr),
1172 		    mfccp->mfcc_parent);
1173 		update_mfc_params(rt, mfccp);
1174 		MRW_WUNLOCK();
1175 		return (0);
1176 	}
1177 
1178 	/*
1179 	 * Find the entry for which the upcall was made and update
1180 	 */
1181 	nstl = 0;
1182 	hash = MFCHASH(mfccp->mfcc_origin, mfccp->mfcc_mcastgrp);
1183 	NET_EPOCH_ENTER(et);
1184 	LIST_FOREACH(rt, &V_mfchashtbl[hash], mfc_hash) {
1185 		if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) &&
1186 		    in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp) &&
1187 		    !buf_ring_empty(rt->mfc_stall_ring)) {
1188 			CTR5(KTR_IPMF,
1189 			   "%s: add mfc orig 0x%08x group %lx parent %x qh %p",
1190 			    __func__, ntohl(mfccp->mfcc_origin.s_addr),
1191 			    (u_long)ntohl(mfccp->mfcc_mcastgrp.s_addr),
1192 			    mfccp->mfcc_parent,
1193 			    rt->mfc_stall_ring);
1194 			if (nstl++)
1195 				CTR1(KTR_IPMF, "%s: multiple matches", __func__);
1196 
1197 			init_mfc_params(rt, mfccp);
1198 			rt->mfc_expire = 0;	/* Don't clean this guy up */
1199 			V_nexpire[hash]--;
1200 
1201 			/* Free queued packets, but attempt to forward them first. */
1202 			while (!buf_ring_empty(rt->mfc_stall_ring)) {
1203 				rte = buf_ring_dequeue_mc(rt->mfc_stall_ring);
1204 				if (rte->ifp != NULL)
1205 					ip_mdq(rte->m, rte->ifp, rt, -1);
1206 				m_freem(rte->m);
1207 				free(rte, M_MRTABLE);
1208 			}
1209 		}
1210 	}
1211 	NET_EPOCH_EXIT(et);
1212 
1213 	/*
1214 	 * It is possible that an entry is being inserted without an upcall
1215 	 */
1216 	if (nstl == 0) {
1217 		CTR1(KTR_IPMF, "%s: adding mfc w/o upcall", __func__);
1218 		LIST_FOREACH(rt, &V_mfchashtbl[hash], mfc_hash) {
1219 			if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) &&
1220 			    in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp)) {
1221 				init_mfc_params(rt, mfccp);
1222 				if (rt->mfc_expire)
1223 					V_nexpire[hash]--;
1224 				rt->mfc_expire = 0;
1225 				break; /* XXX */
1226 			}
1227 		}
1228 
1229 		if (rt == NULL) {		/* no upcall, so make a new entry */
1230 			rt = mfc_alloc();
1231 			if (rt == NULL) {
1232 				MRW_WUNLOCK();
1233 				return (ENOBUFS);
1234 			}
1235 
1236 			init_mfc_params(rt, mfccp);
1237 
1238 			rt->mfc_expire     = 0;
1239 			rt->mfc_bw_meter_leq = NULL;
1240 			rt->mfc_bw_meter_geq = NULL;
1241 
1242 			/* insert new entry at head of hash chain */
1243 			LIST_INSERT_HEAD(&V_mfchashtbl[hash], rt, mfc_hash);
1244 		}
1245 	}
1246 
1247 	MRW_WUNLOCK();
1248 
1249 	return (0);
1250 }
1251 
1252 /*
1253  * Delete an mfc entry
1254  */
1255 static int
del_mfc(struct mfcctl2 * mfccp)1256 del_mfc(struct mfcctl2 *mfccp)
1257 {
1258 	struct in_addr origin;
1259 	struct in_addr mcastgrp;
1260 	struct mfc *rt;
1261 
1262 	origin = mfccp->mfcc_origin;
1263 	mcastgrp = mfccp->mfcc_mcastgrp;
1264 
1265 	CTR3(KTR_IPMF, "%s: delete mfc orig 0x%08x group %lx", __func__,
1266 			ntohl(origin.s_addr), (u_long)ntohl(mcastgrp.s_addr));
1267 
1268 	MRW_WLOCK();
1269 
1270 	LIST_FOREACH(rt, &V_mfchashtbl[MFCHASH(origin, mcastgrp)], mfc_hash) {
1271 		if (in_hosteq(rt->mfc_origin, origin) &&
1272 		    in_hosteq(rt->mfc_mcastgrp, mcastgrp))
1273 			break;
1274 	}
1275 	if (rt == NULL) {
1276 		MRW_WUNLOCK();
1277 		return EADDRNOTAVAIL;
1278 	}
1279 
1280 	expire_mfc(rt);
1281 
1282 	MRW_WUNLOCK();
1283 
1284 	return (0);
1285 }
1286 
1287 /*
1288  * Send a message to the routing daemon on the multicast routing socket.
1289  */
1290 static int
socket_send(struct socket * s,struct mbuf * mm,struct sockaddr_in * src)1291 socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in *src)
1292 {
1293 	if (s) {
1294 		SOCKBUF_LOCK(&s->so_rcv);
1295 		if (sbappendaddr_locked(&s->so_rcv, (struct sockaddr *)src, mm,
1296 		    NULL) != 0) {
1297 			sorwakeup_locked(s);
1298 			return 0;
1299 		}
1300 		soroverflow_locked(s);
1301 	}
1302 	m_freem(mm);
1303 	return -1;
1304 }
1305 
1306 /*
1307  * IP multicast forwarding function. This function assumes that the packet
1308  * pointed to by "ip" has arrived on (or is about to be sent to) the interface
1309  * pointed to by "ifp", and the packet is to be relayed to other networks
1310  * that have members of the packet's destination IP multicast group.
1311  *
1312  * The packet is returned unscathed to the caller, unless it is
1313  * erroneous, in which case a non-zero return value tells the caller to
1314  * discard it.
1315  */
1316 
1317 #define TUNNEL_LEN  12  /* # bytes of IP option for tunnel encapsulation  */
1318 
1319 static int
X_ip_mforward(struct ip * ip,struct ifnet * ifp,struct mbuf * m,struct ip_moptions * imo)1320 X_ip_mforward(struct ip *ip, struct ifnet *ifp, struct mbuf *m,
1321     struct ip_moptions *imo)
1322 {
1323 	struct mfc *rt;
1324 	int error;
1325 	vifi_t vifi;
1326 	struct mbuf *mb0;
1327 	struct rtdetq *rte;
1328 	u_long hash;
1329 	int hlen;
1330 
1331 	M_ASSERTMAPPED(m);
1332 
1333 	CTR3(KTR_IPMF, "ip_mforward: delete mfc orig 0x%08x group %lx ifp %p",
1334 	    ntohl(ip->ip_src.s_addr), (u_long)ntohl(ip->ip_dst.s_addr), ifp);
1335 
1336 	if (ip->ip_hl < (sizeof(struct ip) + TUNNEL_LEN) >> 2 ||
1337 	    ((u_char *)(ip + 1))[1] != IPOPT_LSRR) {
1338 		/*
1339 		 * Packet arrived via a physical interface or
1340 		 * an encapsulated tunnel or a register_vif.
1341 		 */
1342 	} else {
1343 		/*
1344 		 * Packet arrived through a source-route tunnel.
1345 		 * Source-route tunnels are no longer supported.
1346 		 */
1347 		return (1);
1348 	}
1349 
1350 	/*
1351 	 * BEGIN: MCAST ROUTING HOT PATH
1352 	 */
1353 	MRW_RLOCK();
1354 	if (imo && ((vifi = imo->imo_multicast_vif) < V_numvifs)) {
1355 		if (ip->ip_ttl < MAXTTL)
1356 			ip->ip_ttl++; /* compensate for -1 in *_send routines */
1357 		error = ip_mdq(m, ifp, NULL, vifi);
1358 		MRW_RUNLOCK();
1359 		return error;
1360 	}
1361 
1362 	/*
1363 	 * Don't forward a packet with time-to-live of zero or one,
1364 	 * or a packet destined to a local-only group.
1365 	 */
1366 	if (ip->ip_ttl <= 1 || IN_LOCAL_GROUP(ntohl(ip->ip_dst.s_addr))) {
1367 		MRW_RUNLOCK();
1368 		return 0;
1369 	}
1370 
1371 mfc_find_retry:
1372 	/*
1373 	 * Determine forwarding vifs from the forwarding cache table
1374 	 */
1375 	MRTSTAT_INC(mrts_mfc_lookups);
1376 	rt = mfc_find(&ip->ip_src, &ip->ip_dst);
1377 
1378 	/* Entry exists, so forward if necessary */
1379 	if (rt != NULL) {
1380 		error = ip_mdq(m, ifp, rt, -1);
1381 		/* Generic unlock here as we might release R or W lock */
1382 		MRW_UNLOCK();
1383 		return error;
1384 	}
1385 
1386 	/*
1387 	 * END: MCAST ROUTING HOT PATH
1388 	 */
1389 
1390 	/* Further processing must be done with WLOCK taken */
1391 	if ((MRW_WOWNED() == 0) && (MRW_LOCK_TRY_UPGRADE() == 0)) {
1392 		MRW_RUNLOCK();
1393 		MRW_WLOCK();
1394 		goto mfc_find_retry;
1395 	}
1396 
1397 	/*
1398 	 * If we don't have a route for packet's origin,
1399 	 * Make a copy of the packet & send message to routing daemon
1400 	 */
1401 	hlen = ip->ip_hl << 2;
1402 
1403 	MRTSTAT_INC(mrts_mfc_misses);
1404 	MRTSTAT_INC(mrts_no_route);
1405 	CTR2(KTR_IPMF, "ip_mforward: no mfc for (0x%08x,%lx)",
1406 	    ntohl(ip->ip_src.s_addr), (u_long)ntohl(ip->ip_dst.s_addr));
1407 
1408 	/*
1409 	 * Allocate mbufs early so that we don't do extra work if we are
1410 	 * just going to fail anyway.  Make sure to pullup the header so
1411 	 * that other people can't step on it.
1412 	 */
1413 	rte = malloc((sizeof *rte), M_MRTABLE, M_NOWAIT|M_ZERO);
1414 	if (rte == NULL) {
1415 		MRW_WUNLOCK();
1416 		return ENOBUFS;
1417 	}
1418 
1419 	mb0 = m_copypacket(m, M_NOWAIT);
1420 	if (mb0 && (!M_WRITABLE(mb0) || mb0->m_len < hlen))
1421 		mb0 = m_pullup(mb0, hlen);
1422 	if (mb0 == NULL) {
1423 		free(rte, M_MRTABLE);
1424 		MRW_WUNLOCK();
1425 		return ENOBUFS;
1426 	}
1427 
1428 	/* is there an upcall waiting for this flow ? */
1429 	hash = MFCHASH(ip->ip_src, ip->ip_dst);
1430 	LIST_FOREACH(rt, &V_mfchashtbl[hash], mfc_hash)
1431 	{
1432 		if (in_hosteq(ip->ip_src, rt->mfc_origin) &&
1433 		    in_hosteq(ip->ip_dst, rt->mfc_mcastgrp) &&
1434 		    !buf_ring_empty(rt->mfc_stall_ring))
1435 			break;
1436 	}
1437 
1438 	if (rt == NULL) {
1439 		int i;
1440 		struct igmpmsg *im;
1441 		struct sockaddr_in k_igmpsrc = { sizeof k_igmpsrc, AF_INET };
1442 		struct mbuf *mm;
1443 
1444 		/*
1445 		 * Locate the vifi for the incoming interface for this packet.
1446 		 * If none found, drop packet.
1447 		 */
1448 		for (vifi = 0; vifi < V_numvifs &&
1449 		    V_viftable[vifi].v_ifp != ifp; vifi++)
1450 			;
1451 		if (vifi >= V_numvifs) /* vif not found, drop packet */
1452 			goto non_fatal;
1453 
1454 		/* no upcall, so make a new entry */
1455 		rt = mfc_alloc();
1456 		if (rt == NULL)
1457 			goto fail;
1458 
1459 		/* Make a copy of the header to send to the user level process */
1460 		mm = m_copym(mb0, 0, hlen, M_NOWAIT);
1461 		if (mm == NULL)
1462 			goto fail1;
1463 
1464 		/*
1465 		 * Send message to routing daemon to install
1466 		 * a route into the kernel table
1467 		 */
1468 
1469 		im = mtod(mm, struct igmpmsg*);
1470 		im->im_msgtype = IGMPMSG_NOCACHE;
1471 		im->im_mbz = 0;
1472 		im->im_vif = vifi;
1473 
1474 		MRTSTAT_INC(mrts_upcalls);
1475 
1476 		k_igmpsrc.sin_addr = ip->ip_src;
1477 		if (socket_send(V_ip_mrouter, mm, &k_igmpsrc) < 0) {
1478 			CTR0(KTR_IPMF, "ip_mforward: socket queue full");
1479 			MRTSTAT_INC(mrts_upq_sockfull);
1480 			fail1: free(rt, M_MRTABLE);
1481 			fail: free(rte, M_MRTABLE);
1482 			m_freem(mb0);
1483 			MRW_WUNLOCK();
1484 			return ENOBUFS;
1485 		}
1486 
1487 		/* insert new entry at head of hash chain */
1488 		rt->mfc_origin.s_addr = ip->ip_src.s_addr;
1489 		rt->mfc_mcastgrp.s_addr = ip->ip_dst.s_addr;
1490 		rt->mfc_expire = UPCALL_EXPIRE;
1491 		V_nexpire[hash]++;
1492 		for (i = 0; i < V_numvifs; i++) {
1493 			rt->mfc_ttls[i] = 0;
1494 			rt->mfc_flags[i] = 0;
1495 		}
1496 		rt->mfc_parent = -1;
1497 
1498 		/* clear the RP address */
1499 		rt->mfc_rp.s_addr = INADDR_ANY;
1500 		rt->mfc_bw_meter_leq = NULL;
1501 		rt->mfc_bw_meter_geq = NULL;
1502 
1503 		/* initialize pkt counters per src-grp */
1504 		rt->mfc_pkt_cnt = 0;
1505 		rt->mfc_byte_cnt = 0;
1506 		rt->mfc_wrong_if = 0;
1507 		timevalclear(&rt->mfc_last_assert);
1508 
1509 		buf_ring_enqueue(rt->mfc_stall_ring, rte);
1510 
1511 		/* Add RT to hashtable as it didn't exist before */
1512 		LIST_INSERT_HEAD(&V_mfchashtbl[hash], rt, mfc_hash);
1513 	} else {
1514 		/* determine if queue has overflowed */
1515 		if (buf_ring_full(rt->mfc_stall_ring)) {
1516 			MRTSTAT_INC(mrts_upq_ovflw);
1517 			non_fatal: free(rte, M_MRTABLE);
1518 			m_freem(mb0);
1519 			MRW_WUNLOCK();
1520 			return (0);
1521 		}
1522 
1523 		buf_ring_enqueue(rt->mfc_stall_ring, rte);
1524 	}
1525 
1526 	rte->m = mb0;
1527 	rte->ifp = ifp;
1528 
1529 	MRW_WUNLOCK();
1530 
1531 	return 0;
1532 }
1533 
1534 /*
1535  * Clean up the cache entry if upcall is not serviced
1536  */
1537 static void
expire_upcalls(void * arg)1538 expire_upcalls(void *arg)
1539 {
1540 	u_long i;
1541 
1542 	CURVNET_SET((struct vnet *) arg);
1543 
1544 	/*This callout is always run with MRW_WLOCK taken. */
1545 
1546 	for (i = 0; i < mfchashsize; i++) {
1547 		struct mfc *rt, *nrt;
1548 
1549 		if (V_nexpire[i] == 0)
1550 			continue;
1551 
1552 		LIST_FOREACH_SAFE(rt, &V_mfchashtbl[i], mfc_hash, nrt) {
1553 			if (buf_ring_empty(rt->mfc_stall_ring))
1554 				continue;
1555 
1556 			if (rt->mfc_expire == 0 || --rt->mfc_expire > 0)
1557 				continue;
1558 
1559 			MRTSTAT_INC(mrts_cache_cleanups);
1560 			CTR3(KTR_IPMF, "%s: expire (%lx, %lx)", __func__,
1561 			    (u_long)ntohl(rt->mfc_origin.s_addr),
1562 			    (u_long)ntohl(rt->mfc_mcastgrp.s_addr));
1563 
1564 			expire_mfc(rt);
1565 		}
1566 	}
1567 
1568 	callout_reset(&V_expire_upcalls_ch, EXPIRE_TIMEOUT, expire_upcalls,
1569 	    curvnet);
1570 
1571 	CURVNET_RESTORE();
1572 }
1573 
1574 /*
1575  * Packet forwarding routine once entry in the cache is made
1576  */
1577 static int
ip_mdq(struct mbuf * m,struct ifnet * ifp,struct mfc * rt,vifi_t xmt_vif)1578 ip_mdq(struct mbuf *m, struct ifnet *ifp, struct mfc *rt, vifi_t xmt_vif)
1579 {
1580 	struct ip *ip = mtod(m, struct ip *);
1581 	vifi_t vifi;
1582 	int plen = ntohs(ip->ip_len);
1583 
1584 	M_ASSERTMAPPED(m);
1585 	MRW_LOCK_ASSERT();
1586 	NET_EPOCH_ASSERT();
1587 
1588 	/*
1589 	 * If xmt_vif is not -1, send on only the requested vif.
1590 	 *
1591 	 * (since vifi_t is u_short, -1 becomes MAXUSHORT, which > numvifs.)
1592 	 */
1593 	if (xmt_vif < V_numvifs) {
1594 		if (V_viftable[xmt_vif].v_flags & VIFF_REGISTER)
1595 			pim_register_send(ip, V_viftable + xmt_vif, m, rt);
1596 		else
1597 			phyint_send(ip, V_viftable + xmt_vif, m);
1598 		return 1;
1599 	}
1600 
1601 	/*
1602 	 * Don't forward if it didn't arrive from the parent vif for its origin.
1603 	 */
1604 	vifi = rt->mfc_parent;
1605 	if ((vifi >= V_numvifs) || (V_viftable[vifi].v_ifp != ifp)) {
1606 		CTR4(KTR_IPMF, "%s: rx on wrong ifp %p (vifi %d, v_ifp %p)",
1607 				__func__, ifp, (int)vifi, V_viftable[vifi].v_ifp);
1608 		MRTSTAT_INC(mrts_wrong_if);
1609 		++rt->mfc_wrong_if;
1610 		/*
1611 		 * If we are doing PIM assert processing, send a message
1612 		 * to the routing daemon.
1613 		 *
1614 		 * XXX: A PIM-SM router needs the WRONGVIF detection so it
1615 		 * can complete the SPT switch, regardless of the type
1616 		 * of the iif (broadcast media, GRE tunnel, etc).
1617 		 */
1618 		if (V_pim_assert_enabled && (vifi < V_numvifs) &&
1619 		    V_viftable[vifi].v_ifp) {
1620 			if (ifp == V_multicast_register_if)
1621 				PIMSTAT_INC(pims_rcv_registers_wrongiif);
1622 
1623 			/* Get vifi for the incoming packet */
1624 			for (vifi = 0; vifi < V_numvifs && V_viftable[vifi].v_ifp != ifp; vifi++)
1625 				;
1626 			if (vifi >= V_numvifs)
1627 				return 0;	/* The iif is not found: ignore the packet. */
1628 
1629 			if (rt->mfc_flags[vifi] & MRT_MFC_FLAGS_DISABLE_WRONGVIF)
1630 				return 0;	/* WRONGVIF disabled: ignore the packet */
1631 
1632 			if (ratecheck(&rt->mfc_last_assert, &pim_assert_interval)) {
1633 				struct sockaddr_in k_igmpsrc = { sizeof k_igmpsrc, AF_INET };
1634 				struct igmpmsg *im;
1635 				int hlen = ip->ip_hl << 2;
1636 				struct mbuf *mm = m_copym(m, 0, hlen, M_NOWAIT);
1637 
1638 				if (mm && (!M_WRITABLE(mm) || mm->m_len < hlen))
1639 					mm = m_pullup(mm, hlen);
1640 				if (mm == NULL)
1641 					return ENOBUFS;
1642 
1643 				im = mtod(mm, struct igmpmsg *);
1644 				im->im_msgtype = IGMPMSG_WRONGVIF;
1645 				im->im_mbz = 0;
1646 				im->im_vif = vifi;
1647 
1648 				MRTSTAT_INC(mrts_upcalls);
1649 
1650 				k_igmpsrc.sin_addr = im->im_src;
1651 				if (socket_send(V_ip_mrouter, mm, &k_igmpsrc) < 0) {
1652 					CTR1(KTR_IPMF, "%s: socket queue full", __func__);
1653 					MRTSTAT_INC(mrts_upq_sockfull);
1654 					return ENOBUFS;
1655 				}
1656 			}
1657 		}
1658 		return 0;
1659 	}
1660 
1661 	/* If I sourced this packet, it counts as output, else it was input. */
1662 	mtx_lock_spin(&V_viftable[vifi].v_spin);
1663 	if (in_hosteq(ip->ip_src, V_viftable[vifi].v_lcl_addr)) {
1664 		V_viftable[vifi].v_pkt_out++;
1665 		V_viftable[vifi].v_bytes_out += plen;
1666 	} else {
1667 		V_viftable[vifi].v_pkt_in++;
1668 		V_viftable[vifi].v_bytes_in += plen;
1669 	}
1670 	mtx_unlock_spin(&V_viftable[vifi].v_spin);
1671 
1672 	rt->mfc_pkt_cnt++;
1673 	rt->mfc_byte_cnt += plen;
1674 
1675 	/*
1676 	 * For each vif, decide if a copy of the packet should be forwarded.
1677 	 * Forward if:
1678 	 *		- the ttl exceeds the vif's threshold
1679 	 *		- there are group members downstream on interface
1680 	 */
1681 	for (vifi = 0; vifi < V_numvifs; vifi++)
1682 		if ((rt->mfc_ttls[vifi] > 0) && (ip->ip_ttl > rt->mfc_ttls[vifi])) {
1683 			V_viftable[vifi].v_pkt_out++;
1684 			V_viftable[vifi].v_bytes_out += plen;
1685 			if (V_viftable[vifi].v_flags & VIFF_REGISTER)
1686 				pim_register_send(ip, V_viftable + vifi, m, rt);
1687 			else
1688 				phyint_send(ip, V_viftable + vifi, m);
1689 		}
1690 
1691 	/*
1692 	 * Perform upcall-related bw measuring.
1693 	 */
1694 	if ((rt->mfc_bw_meter_geq != NULL) || (rt->mfc_bw_meter_leq != NULL)) {
1695 		struct bw_meter *x;
1696 		struct timeval now;
1697 
1698 		microtime(&now);
1699 		/* Process meters for Greater-or-EQual case */
1700 		for (x = rt->mfc_bw_meter_geq; x != NULL; x = x->bm_mfc_next)
1701 			bw_meter_geq_receive_packet(x, plen, &now);
1702 
1703 		/* Process meters for Lower-or-EQual case */
1704 		for (x = rt->mfc_bw_meter_leq; x != NULL; x = x->bm_mfc_next) {
1705 			/*
1706 			 * Record that a packet is received.
1707 			 * Spin lock has to be taken as callout context
1708 			 * (expire_bw_meter_leq) might modify these fields
1709 			 * as well
1710 			 */
1711 			mtx_lock_spin(&x->bm_spin);
1712 			x->bm_measured.b_packets++;
1713 			x->bm_measured.b_bytes += plen;
1714 			mtx_unlock_spin(&x->bm_spin);
1715 		}
1716 	}
1717 
1718 	return 0;
1719 }
1720 
1721 /*
1722  * Check if a vif number is legal/ok. This is used by in_mcast.c.
1723  */
1724 static int
X_legal_vif_num(int vif)1725 X_legal_vif_num(int vif)
1726 {
1727 	int ret;
1728 
1729 	ret = 0;
1730 	if (vif < 0)
1731 		return (ret);
1732 
1733 	MRW_RLOCK();
1734 	if (vif < V_numvifs)
1735 		ret = 1;
1736 	MRW_RUNLOCK();
1737 
1738 	return (ret);
1739 }
1740 
1741 /*
1742  * Return the local address used by this vif
1743  */
1744 static u_long
X_ip_mcast_src(int vifi)1745 X_ip_mcast_src(int vifi)
1746 {
1747 	in_addr_t addr;
1748 
1749 	addr = INADDR_ANY;
1750 	if (vifi < 0)
1751 		return (addr);
1752 
1753 	MRW_RLOCK();
1754 	if (vifi < V_numvifs)
1755 		addr = V_viftable[vifi].v_lcl_addr.s_addr;
1756 	MRW_RUNLOCK();
1757 
1758 	return (addr);
1759 }
1760 
1761 static void
phyint_send(struct ip * ip,struct vif * vifp,struct mbuf * m)1762 phyint_send(struct ip *ip, struct vif *vifp, struct mbuf *m)
1763 {
1764 	struct mbuf *mb_copy;
1765 	int hlen = ip->ip_hl << 2;
1766 
1767 	MRW_LOCK_ASSERT();
1768 	M_ASSERTMAPPED(m);
1769 
1770 	/*
1771 	 * Make a new reference to the packet; make sure that
1772 	 * the IP header is actually copied, not just referenced,
1773 	 * so that ip_output() only scribbles on the copy.
1774 	 */
1775 	mb_copy = m_copypacket(m, M_NOWAIT);
1776 	if (mb_copy && (!M_WRITABLE(mb_copy) || mb_copy->m_len < hlen))
1777 		mb_copy = m_pullup(mb_copy, hlen);
1778 	if (mb_copy == NULL)
1779 		return;
1780 
1781 	send_packet(vifp, mb_copy);
1782 }
1783 
1784 static void
send_packet(struct vif * vifp,struct mbuf * m)1785 send_packet(struct vif *vifp, struct mbuf *m)
1786 {
1787 	struct ip_moptions imo;
1788 	int error __unused;
1789 
1790 	MRW_LOCK_ASSERT();
1791 	NET_EPOCH_ASSERT();
1792 
1793 	imo.imo_multicast_ifp  = vifp->v_ifp;
1794 	imo.imo_multicast_ttl  = mtod(m, struct ip *)->ip_ttl - 1;
1795 	imo.imo_multicast_loop = !!in_mcast_loop;
1796 	imo.imo_multicast_vif  = -1;
1797 	STAILQ_INIT(&imo.imo_head);
1798 
1799 	/*
1800 	 * Re-entrancy should not be a problem here, because
1801 	 * the packets that we send out and are looped back at us
1802 	 * should get rejected because they appear to come from
1803 	 * the loopback interface, thus preventing looping.
1804 	 */
1805 	error = ip_output(m, NULL, NULL, IP_FORWARDING, &imo, NULL);
1806 	CTR3(KTR_IPMF, "%s: vif %td err %d", __func__,
1807 	    (ptrdiff_t)(vifp - V_viftable), error);
1808 }
1809 
1810 /*
1811  * Stubs for old RSVP socket shim implementation.
1812  */
1813 
1814 static int
X_ip_rsvp_vif(struct socket * so __unused,struct sockopt * sopt __unused)1815 X_ip_rsvp_vif(struct socket *so __unused, struct sockopt *sopt __unused)
1816 {
1817 
1818 	return (EOPNOTSUPP);
1819 }
1820 
1821 static void
X_ip_rsvp_force_done(struct socket * so __unused)1822 X_ip_rsvp_force_done(struct socket *so __unused)
1823 {
1824 
1825 }
1826 
1827 static int
X_rsvp_input(struct mbuf ** mp,int * offp,int proto)1828 X_rsvp_input(struct mbuf **mp, int *offp, int proto)
1829 {
1830 	struct mbuf *m;
1831 
1832 	m = *mp;
1833 	*mp = NULL;
1834 	if (!V_rsvp_on)
1835 		m_freem(m);
1836 	return (IPPROTO_DONE);
1837 }
1838 
1839 /*
1840  * Code for bandwidth monitors
1841  */
1842 
1843 /*
1844  * Define common interface for timeval-related methods
1845  */
1846 #define	BW_TIMEVALCMP(tvp, uvp, cmp) timevalcmp((tvp), (uvp), cmp)
1847 #define	BW_TIMEVALDECR(vvp, uvp) timevalsub((vvp), (uvp))
1848 #define	BW_TIMEVALADD(vvp, uvp) timevaladd((vvp), (uvp))
1849 
1850 static uint32_t
compute_bw_meter_flags(struct bw_upcall * req)1851 compute_bw_meter_flags(struct bw_upcall *req)
1852 {
1853 	uint32_t flags = 0;
1854 
1855 	if (req->bu_flags & BW_UPCALL_UNIT_PACKETS)
1856 		flags |= BW_METER_UNIT_PACKETS;
1857 	if (req->bu_flags & BW_UPCALL_UNIT_BYTES)
1858 		flags |= BW_METER_UNIT_BYTES;
1859 	if (req->bu_flags & BW_UPCALL_GEQ)
1860 		flags |= BW_METER_GEQ;
1861 	if (req->bu_flags & BW_UPCALL_LEQ)
1862 		flags |= BW_METER_LEQ;
1863 
1864 	return flags;
1865 }
1866 
1867 static void
expire_bw_meter_leq(void * arg)1868 expire_bw_meter_leq(void *arg)
1869 {
1870 	struct bw_meter *x = arg;
1871 	struct timeval now;
1872 	/*
1873 	 * INFO:
1874 	 * callout is always executed with MRW_WLOCK taken
1875 	 */
1876 
1877 	CURVNET_SET((struct vnet *)x->arg);
1878 
1879 	microtime(&now);
1880 
1881 	/*
1882 	 * Test if we should deliver an upcall
1883 	 */
1884 	if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
1885 	    (x->bm_measured.b_packets <= x->bm_threshold.b_packets)) ||
1886 	    ((x->bm_flags & BW_METER_UNIT_BYTES) &&
1887 	    (x->bm_measured.b_bytes <= x->bm_threshold.b_bytes))) {
1888 		/* Prepare an upcall for delivery */
1889 		bw_meter_prepare_upcall(x, &now);
1890 	}
1891 
1892 	/* Send all upcalls that are pending delivery */
1893 	taskqueue_enqueue(V_task_queue, &V_task);
1894 
1895 	/* Reset counters */
1896 	x->bm_start_time = now;
1897 	/* Spin lock has to be taken as ip_forward context
1898 	 * might modify these fields as well
1899 	 */
1900 	mtx_lock_spin(&x->bm_spin);
1901 	x->bm_measured.b_bytes = 0;
1902 	x->bm_measured.b_packets = 0;
1903 	mtx_unlock_spin(&x->bm_spin);
1904 
1905 	callout_schedule(&x->bm_meter_callout, tvtohz(&x->bm_threshold.b_time));
1906 
1907 	CURVNET_RESTORE();
1908 }
1909 
1910 /*
1911  * Add a bw_meter entry
1912  */
1913 static int
add_bw_upcall(struct bw_upcall * req)1914 add_bw_upcall(struct bw_upcall *req)
1915 {
1916 	struct mfc *mfc;
1917 	struct timeval delta = { BW_UPCALL_THRESHOLD_INTERVAL_MIN_SEC,
1918 	BW_UPCALL_THRESHOLD_INTERVAL_MIN_USEC };
1919 	struct timeval now;
1920 	struct bw_meter *x, **bwm_ptr;
1921 	uint32_t flags;
1922 
1923 	if (!(V_mrt_api_config & MRT_MFC_BW_UPCALL))
1924 		return EOPNOTSUPP;
1925 
1926 	/* Test if the flags are valid */
1927 	if (!(req->bu_flags & (BW_UPCALL_UNIT_PACKETS | BW_UPCALL_UNIT_BYTES)))
1928 		return EINVAL;
1929 	if (!(req->bu_flags & (BW_UPCALL_GEQ | BW_UPCALL_LEQ)))
1930 		return EINVAL;
1931 	if ((req->bu_flags & (BW_UPCALL_GEQ | BW_UPCALL_LEQ)) == (BW_UPCALL_GEQ | BW_UPCALL_LEQ))
1932 		return EINVAL;
1933 
1934 	/* Test if the threshold time interval is valid */
1935 	if (BW_TIMEVALCMP(&req->bu_threshold.b_time, &delta, <))
1936 		return EINVAL;
1937 
1938 	flags = compute_bw_meter_flags(req);
1939 
1940 	/*
1941 	 * Find if we have already same bw_meter entry
1942 	 */
1943 	MRW_WLOCK();
1944 	mfc = mfc_find(&req->bu_src, &req->bu_dst);
1945 	if (mfc == NULL) {
1946 		MRW_WUNLOCK();
1947 		return EADDRNOTAVAIL;
1948 	}
1949 
1950 	/* Choose an appropriate bw_meter list */
1951 	if (req->bu_flags & BW_UPCALL_GEQ)
1952 		bwm_ptr = &mfc->mfc_bw_meter_geq;
1953 	else
1954 		bwm_ptr = &mfc->mfc_bw_meter_leq;
1955 
1956 	for (x = *bwm_ptr; x != NULL; x = x->bm_mfc_next) {
1957 		if ((BW_TIMEVALCMP(&x->bm_threshold.b_time,
1958 		    &req->bu_threshold.b_time, ==))
1959 		    && (x->bm_threshold.b_packets
1960 		    == req->bu_threshold.b_packets)
1961 		    && (x->bm_threshold.b_bytes
1962 		    == req->bu_threshold.b_bytes)
1963 		    && (x->bm_flags & BW_METER_USER_FLAGS)
1964 		    == flags) {
1965 			MRW_WUNLOCK();
1966 			return 0; /* XXX Already installed */
1967 		}
1968 	}
1969 
1970 	/* Allocate the new bw_meter entry */
1971 	x = malloc(sizeof(*x), M_BWMETER, M_ZERO | M_NOWAIT);
1972 	if (x == NULL) {
1973 		MRW_WUNLOCK();
1974 		return ENOBUFS;
1975 	}
1976 
1977 	/* Set the new bw_meter entry */
1978 	x->bm_threshold.b_time = req->bu_threshold.b_time;
1979 	microtime(&now);
1980 	x->bm_start_time = now;
1981 	x->bm_threshold.b_packets = req->bu_threshold.b_packets;
1982 	x->bm_threshold.b_bytes = req->bu_threshold.b_bytes;
1983 	x->bm_measured.b_packets = 0;
1984 	x->bm_measured.b_bytes = 0;
1985 	x->bm_flags = flags;
1986 	x->bm_time_next = NULL;
1987 	x->bm_mfc = mfc;
1988 	x->arg = curvnet;
1989 	sprintf(x->bm_spin_name, "BM spin %p", x);
1990 	mtx_init(&x->bm_spin, x->bm_spin_name, NULL, MTX_SPIN);
1991 
1992 	/* For LEQ case create periodic callout */
1993 	if (req->bu_flags & BW_UPCALL_LEQ) {
1994 		callout_init_rw(&x->bm_meter_callout, &mrouter_lock, CALLOUT_SHAREDLOCK);
1995 		callout_reset(&x->bm_meter_callout, tvtohz(&x->bm_threshold.b_time),
1996 		    expire_bw_meter_leq, x);
1997 	}
1998 
1999 	/* Add the new bw_meter entry to the front of entries for this MFC */
2000 	x->bm_mfc_next = *bwm_ptr;
2001 	*bwm_ptr = x;
2002 
2003 	MRW_WUNLOCK();
2004 
2005 	return 0;
2006 }
2007 
2008 static void
free_bw_list(struct bw_meter * list)2009 free_bw_list(struct bw_meter *list)
2010 {
2011 	while (list != NULL) {
2012 		struct bw_meter *x = list;
2013 
2014 		/* MRW_WLOCK must be held here */
2015 		if (x->bm_flags & BW_METER_LEQ) {
2016 			callout_drain(&x->bm_meter_callout);
2017 			mtx_destroy(&x->bm_spin);
2018 		}
2019 
2020 		list = list->bm_mfc_next;
2021 		free(x, M_BWMETER);
2022 	}
2023 }
2024 
2025 /*
2026  * Delete one or multiple bw_meter entries
2027  */
2028 static int
del_bw_upcall(struct bw_upcall * req)2029 del_bw_upcall(struct bw_upcall *req)
2030 {
2031 	struct mfc *mfc;
2032 	struct bw_meter *x, **bwm_ptr;
2033 
2034 	if (!(V_mrt_api_config & MRT_MFC_BW_UPCALL))
2035 		return EOPNOTSUPP;
2036 
2037 	MRW_WLOCK();
2038 
2039 	/* Find the corresponding MFC entry */
2040 	mfc = mfc_find(&req->bu_src, &req->bu_dst);
2041 	if (mfc == NULL) {
2042 		MRW_WUNLOCK();
2043 		return EADDRNOTAVAIL;
2044 	} else if (req->bu_flags & BW_UPCALL_DELETE_ALL) {
2045 		/*
2046 		 * Delete all bw_meter entries for this mfc
2047 		 */
2048 		struct bw_meter *list;
2049 
2050 		/* Free LEQ list */
2051 		list = mfc->mfc_bw_meter_leq;
2052 		mfc->mfc_bw_meter_leq = NULL;
2053 		free_bw_list(list);
2054 
2055 		/* Free GEQ list */
2056 		list = mfc->mfc_bw_meter_geq;
2057 		mfc->mfc_bw_meter_geq = NULL;
2058 		free_bw_list(list);
2059 		MRW_WUNLOCK();
2060 		return 0;
2061 	} else {			/* Delete a single bw_meter entry */
2062 		struct bw_meter *prev;
2063 		uint32_t flags = 0;
2064 
2065 		flags = compute_bw_meter_flags(req);
2066 
2067 		/* Choose an appropriate bw_meter list */
2068 		if (req->bu_flags & BW_UPCALL_GEQ)
2069 			bwm_ptr = &mfc->mfc_bw_meter_geq;
2070 		else
2071 			bwm_ptr = &mfc->mfc_bw_meter_leq;
2072 
2073 		/* Find the bw_meter entry to delete */
2074 		for (prev = NULL, x = *bwm_ptr; x != NULL;
2075 				prev = x, x = x->bm_mfc_next) {
2076 			if ((BW_TIMEVALCMP(&x->bm_threshold.b_time, &req->bu_threshold.b_time, ==)) &&
2077 			    (x->bm_threshold.b_packets == req->bu_threshold.b_packets) &&
2078 			    (x->bm_threshold.b_bytes == req->bu_threshold.b_bytes) &&
2079 			    (x->bm_flags & BW_METER_USER_FLAGS) == flags)
2080 				break;
2081 		}
2082 		if (x != NULL) { /* Delete entry from the list for this MFC */
2083 			if (prev != NULL)
2084 				prev->bm_mfc_next = x->bm_mfc_next;	/* remove from middle*/
2085 			else
2086 				*bwm_ptr = x->bm_mfc_next;/* new head of list */
2087 
2088 			if (req->bu_flags & BW_UPCALL_LEQ)
2089 				callout_stop(&x->bm_meter_callout);
2090 
2091 			MRW_WUNLOCK();
2092 			/* Free the bw_meter entry */
2093 			free(x, M_BWMETER);
2094 			return 0;
2095 		} else {
2096 			MRW_WUNLOCK();
2097 			return EINVAL;
2098 		}
2099 	}
2100 	__assert_unreachable();
2101 }
2102 
2103 /*
2104  * Perform bandwidth measurement processing that may result in an upcall
2105  */
2106 static void
bw_meter_geq_receive_packet(struct bw_meter * x,int plen,struct timeval * nowp)2107 bw_meter_geq_receive_packet(struct bw_meter *x, int plen, struct timeval *nowp)
2108 {
2109 	struct timeval delta;
2110 
2111 	MRW_LOCK_ASSERT();
2112 
2113 	delta = *nowp;
2114 	BW_TIMEVALDECR(&delta, &x->bm_start_time);
2115 
2116 	/*
2117 	 * Processing for ">=" type of bw_meter entry.
2118 	 * bm_spin does not have to be hold here as in GEQ
2119 	 * case this is the only context accessing bm_measured.
2120 	 */
2121 	if (BW_TIMEVALCMP(&delta, &x->bm_threshold.b_time, >)) {
2122 	    /* Reset the bw_meter entry */
2123 	    x->bm_start_time = *nowp;
2124 	    x->bm_measured.b_packets = 0;
2125 	    x->bm_measured.b_bytes = 0;
2126 	    x->bm_flags &= ~BW_METER_UPCALL_DELIVERED;
2127 	}
2128 
2129 	/* Record that a packet is received */
2130 	x->bm_measured.b_packets++;
2131 	x->bm_measured.b_bytes += plen;
2132 
2133 	/*
2134 	 * Test if we should deliver an upcall
2135 	 */
2136 	if (!(x->bm_flags & BW_METER_UPCALL_DELIVERED)) {
2137 		if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
2138 		    (x->bm_measured.b_packets >= x->bm_threshold.b_packets)) ||
2139 		    ((x->bm_flags & BW_METER_UNIT_BYTES) &&
2140 		    (x->bm_measured.b_bytes >= x->bm_threshold.b_bytes))) {
2141 			/* Prepare an upcall for delivery */
2142 			bw_meter_prepare_upcall(x, nowp);
2143 			x->bm_flags |= BW_METER_UPCALL_DELIVERED;
2144 		}
2145 	}
2146 }
2147 
2148 /*
2149  * Prepare a bandwidth-related upcall
2150  */
2151 static void
bw_meter_prepare_upcall(struct bw_meter * x,struct timeval * nowp)2152 bw_meter_prepare_upcall(struct bw_meter *x, struct timeval *nowp)
2153 {
2154 	struct timeval delta;
2155 	struct bw_upcall *u;
2156 
2157 	MRW_LOCK_ASSERT();
2158 
2159 	/*
2160 	 * Compute the measured time interval
2161 	 */
2162 	delta = *nowp;
2163 	BW_TIMEVALDECR(&delta, &x->bm_start_time);
2164 
2165 	/*
2166 	 * Set the bw_upcall entry
2167 	 */
2168 	u = malloc(sizeof(struct bw_upcall), M_MRTABLE, M_NOWAIT | M_ZERO);
2169 	if (!u) {
2170 		log(LOG_WARNING, "bw_meter_prepare_upcall: cannot allocate entry\n");
2171 		return;
2172 	}
2173 	u->bu_src = x->bm_mfc->mfc_origin;
2174 	u->bu_dst = x->bm_mfc->mfc_mcastgrp;
2175 	u->bu_threshold.b_time = x->bm_threshold.b_time;
2176 	u->bu_threshold.b_packets = x->bm_threshold.b_packets;
2177 	u->bu_threshold.b_bytes = x->bm_threshold.b_bytes;
2178 	u->bu_measured.b_time = delta;
2179 	u->bu_measured.b_packets = x->bm_measured.b_packets;
2180 	u->bu_measured.b_bytes = x->bm_measured.b_bytes;
2181 	u->bu_flags = 0;
2182 	if (x->bm_flags & BW_METER_UNIT_PACKETS)
2183 		u->bu_flags |= BW_UPCALL_UNIT_PACKETS;
2184 	if (x->bm_flags & BW_METER_UNIT_BYTES)
2185 		u->bu_flags |= BW_UPCALL_UNIT_BYTES;
2186 	if (x->bm_flags & BW_METER_GEQ)
2187 		u->bu_flags |= BW_UPCALL_GEQ;
2188 	if (x->bm_flags & BW_METER_LEQ)
2189 		u->bu_flags |= BW_UPCALL_LEQ;
2190 
2191 	if (buf_ring_enqueue(V_bw_upcalls_ring, u))
2192 		log(LOG_WARNING, "bw_meter_prepare_upcall: cannot enqueue upcall\n");
2193 	if (buf_ring_count(V_bw_upcalls_ring) > (BW_UPCALLS_MAX / 2)) {
2194 		taskqueue_enqueue(V_task_queue, &V_task);
2195 	}
2196 }
2197 /*
2198  * Send the pending bandwidth-related upcalls
2199  */
2200 static void
bw_upcalls_send(void)2201 bw_upcalls_send(void)
2202 {
2203 	struct mbuf *m;
2204 	int len = 0;
2205 	struct bw_upcall *bu;
2206 	struct sockaddr_in k_igmpsrc = { sizeof k_igmpsrc, AF_INET };
2207 	static struct igmpmsg igmpmsg = {
2208 		0,		/* unused1 */
2209 		0,		/* unused2 */
2210 		IGMPMSG_BW_UPCALL,/* im_msgtype */
2211 		0,		/* im_mbz  */
2212 		0,		/* im_vif  */
2213 		0,		/* unused3 */
2214 		{ 0 },		/* im_src  */
2215 		{ 0 }		/* im_dst  */
2216 	};
2217 
2218 	MRW_LOCK_ASSERT();
2219 
2220 	if (buf_ring_empty(V_bw_upcalls_ring))
2221 		return;
2222 
2223 	/*
2224 	 * Allocate a new mbuf, initialize it with the header and
2225 	 * the payload for the pending calls.
2226 	 */
2227 	m = m_gethdr(M_NOWAIT, MT_DATA);
2228 	if (m == NULL) {
2229 		log(LOG_WARNING, "bw_upcalls_send: cannot allocate mbuf\n");
2230 		return;
2231 	}
2232 
2233 	m_copyback(m, 0, sizeof(struct igmpmsg), (caddr_t)&igmpmsg);
2234 	len += sizeof(struct igmpmsg);
2235 	while ((bu = buf_ring_dequeue_mc(V_bw_upcalls_ring)) != NULL) {
2236 		m_copyback(m, len, sizeof(struct bw_upcall), (caddr_t)bu);
2237 		len += sizeof(struct bw_upcall);
2238 		free(bu, M_MRTABLE);
2239 	}
2240 
2241 	/*
2242 	 * Send the upcalls
2243 	 * XXX do we need to set the address in k_igmpsrc ?
2244 	 */
2245 	MRTSTAT_INC(mrts_upcalls);
2246 	if (socket_send(V_ip_mrouter, m, &k_igmpsrc) < 0) {
2247 		log(LOG_WARNING, "bw_upcalls_send: ip_mrouter socket queue full\n");
2248 		MRTSTAT_INC(mrts_upq_sockfull);
2249 	}
2250 }
2251 
2252 /*
2253  * A periodic function for sending all upcalls that are pending delivery
2254  */
2255 static void
expire_bw_upcalls_send(void * arg)2256 expire_bw_upcalls_send(void *arg)
2257 {
2258 	CURVNET_SET((struct vnet *) arg);
2259 
2260 	/* This callout is run with MRW_RLOCK taken */
2261 
2262 	bw_upcalls_send();
2263 
2264 	callout_reset(&V_bw_upcalls_ch, BW_UPCALLS_PERIOD, expire_bw_upcalls_send,
2265 	    curvnet);
2266 	CURVNET_RESTORE();
2267 }
2268 
2269 /*
2270  * End of bandwidth monitoring code
2271  */
2272 
2273 /*
2274  * Send the packet up to the user daemon, or eventually do kernel encapsulation
2275  *
2276  */
2277 static int
pim_register_send(struct ip * ip,struct vif * vifp,struct mbuf * m,struct mfc * rt)2278 pim_register_send(struct ip *ip, struct vif *vifp, struct mbuf *m,
2279     struct mfc *rt)
2280 {
2281 	struct mbuf *mb_copy, *mm;
2282 
2283 	/*
2284 	 * Do not send IGMP_WHOLEPKT notifications to userland, if the
2285 	 * rendezvous point was unspecified, and we were told not to.
2286 	 */
2287 	if (pim_squelch_wholepkt != 0 && (V_mrt_api_config & MRT_MFC_RP) &&
2288 	    in_nullhost(rt->mfc_rp))
2289 		return 0;
2290 
2291 	mb_copy = pim_register_prepare(ip, m);
2292 	if (mb_copy == NULL)
2293 		return ENOBUFS;
2294 
2295 	/*
2296 	 * Send all the fragments. Note that the mbuf for each fragment
2297 	 * is freed by the sending machinery.
2298 	 */
2299 	for (mm = mb_copy; mm; mm = mb_copy) {
2300 		mb_copy = mm->m_nextpkt;
2301 		mm->m_nextpkt = 0;
2302 		mm = m_pullup(mm, sizeof(struct ip));
2303 		if (mm != NULL) {
2304 			ip = mtod(mm, struct ip *);
2305 			if ((V_mrt_api_config & MRT_MFC_RP) && !in_nullhost(rt->mfc_rp)) {
2306 				pim_register_send_rp(ip, vifp, mm, rt);
2307 			} else {
2308 				pim_register_send_upcall(ip, vifp, mm, rt);
2309 			}
2310 		}
2311 	}
2312 
2313 	return 0;
2314 }
2315 
2316 /*
2317  * Return a copy of the data packet that is ready for PIM Register
2318  * encapsulation.
2319  * XXX: Note that in the returned copy the IP header is a valid one.
2320  */
2321 static struct mbuf *
pim_register_prepare(struct ip * ip,struct mbuf * m)2322 pim_register_prepare(struct ip *ip, struct mbuf *m)
2323 {
2324 	struct mbuf *mb_copy = NULL;
2325 	int mtu;
2326 
2327 	/* Take care of delayed checksums */
2328 	if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2329 		in_delayed_cksum(m);
2330 		m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2331 	}
2332 
2333 	/*
2334 	 * Copy the old packet & pullup its IP header into the
2335 	 * new mbuf so we can modify it.
2336 	 */
2337 	mb_copy = m_copypacket(m, M_NOWAIT);
2338 	if (mb_copy == NULL)
2339 		return NULL;
2340 	mb_copy = m_pullup(mb_copy, ip->ip_hl << 2);
2341 	if (mb_copy == NULL)
2342 		return NULL;
2343 
2344 	/* take care of the TTL */
2345 	ip = mtod(mb_copy, struct ip *);
2346 	--ip->ip_ttl;
2347 
2348 	/* Compute the MTU after the PIM Register encapsulation */
2349 	mtu = 0xffff - sizeof(pim_encap_iphdr) - sizeof(pim_encap_pimhdr);
2350 
2351 	if (ntohs(ip->ip_len) <= mtu) {
2352 		/* Turn the IP header into a valid one */
2353 		ip->ip_sum = 0;
2354 		ip->ip_sum = in_cksum(mb_copy, ip->ip_hl << 2);
2355 	} else {
2356 		/* Fragment the packet */
2357 		mb_copy->m_pkthdr.csum_flags |= CSUM_IP;
2358 		if (ip_fragment(ip, &mb_copy, mtu, 0) != 0) {
2359 			m_freem(mb_copy);
2360 			return NULL;
2361 		}
2362 	}
2363 	return mb_copy;
2364 }
2365 
2366 /*
2367  * Send an upcall with the data packet to the user-level process.
2368  */
2369 static int
pim_register_send_upcall(struct ip * ip,struct vif * vifp,struct mbuf * mb_copy,struct mfc * rt)2370 pim_register_send_upcall(struct ip *ip, struct vif *vifp,
2371     struct mbuf *mb_copy, struct mfc *rt)
2372 {
2373 	struct mbuf *mb_first;
2374 	int len = ntohs(ip->ip_len);
2375 	struct igmpmsg *im;
2376 	struct sockaddr_in k_igmpsrc = { sizeof k_igmpsrc, AF_INET };
2377 
2378 	MRW_LOCK_ASSERT();
2379 
2380 	/*
2381 	 * Add a new mbuf with an upcall header
2382 	 */
2383 	mb_first = m_gethdr(M_NOWAIT, MT_DATA);
2384 	if (mb_first == NULL) {
2385 		m_freem(mb_copy);
2386 		return ENOBUFS;
2387 	}
2388 	mb_first->m_data += max_linkhdr;
2389 	mb_first->m_pkthdr.len = len + sizeof(struct igmpmsg);
2390 	mb_first->m_len = sizeof(struct igmpmsg);
2391 	mb_first->m_next = mb_copy;
2392 
2393 	/* Send message to routing daemon */
2394 	im = mtod(mb_first, struct igmpmsg *);
2395 	im->im_msgtype	= IGMPMSG_WHOLEPKT;
2396 	im->im_mbz		= 0;
2397 	im->im_vif		= vifp - V_viftable;
2398 	im->im_src		= ip->ip_src;
2399 	im->im_dst		= ip->ip_dst;
2400 
2401 	k_igmpsrc.sin_addr	= ip->ip_src;
2402 
2403 	MRTSTAT_INC(mrts_upcalls);
2404 
2405 	if (socket_send(V_ip_mrouter, mb_first, &k_igmpsrc) < 0) {
2406 		CTR1(KTR_IPMF, "%s: socket queue full", __func__);
2407 		MRTSTAT_INC(mrts_upq_sockfull);
2408 		return ENOBUFS;
2409 	}
2410 
2411 	/* Keep statistics */
2412 	PIMSTAT_INC(pims_snd_registers_msgs);
2413 	PIMSTAT_ADD(pims_snd_registers_bytes, len);
2414 
2415 	return 0;
2416 }
2417 
2418 /*
2419  * Encapsulate the data packet in PIM Register message and send it to the RP.
2420  */
2421 static int
pim_register_send_rp(struct ip * ip,struct vif * vifp,struct mbuf * mb_copy,struct mfc * rt)2422 pim_register_send_rp(struct ip *ip, struct vif *vifp, struct mbuf *mb_copy,
2423     struct mfc *rt)
2424 {
2425 	struct mbuf *mb_first;
2426 	struct ip *ip_outer;
2427 	struct pim_encap_pimhdr *pimhdr;
2428 	int len = ntohs(ip->ip_len);
2429 	vifi_t vifi = rt->mfc_parent;
2430 
2431 	MRW_LOCK_ASSERT();
2432 
2433 	if ((vifi >= V_numvifs) || in_nullhost(V_viftable[vifi].v_lcl_addr)) {
2434 		m_freem(mb_copy);
2435 		return EADDRNOTAVAIL;		/* The iif vif is invalid */
2436 	}
2437 
2438 	/*
2439 	 * Add a new mbuf with the encapsulating header
2440 	 */
2441 	mb_first = m_gethdr(M_NOWAIT, MT_DATA);
2442 	if (mb_first == NULL) {
2443 		m_freem(mb_copy);
2444 		return ENOBUFS;
2445 	}
2446 	mb_first->m_data += max_linkhdr;
2447 	mb_first->m_len = sizeof(pim_encap_iphdr) + sizeof(pim_encap_pimhdr);
2448 	mb_first->m_next = mb_copy;
2449 
2450 	mb_first->m_pkthdr.len = len + mb_first->m_len;
2451 
2452 	/*
2453 	 * Fill in the encapsulating IP and PIM header
2454 	 */
2455 	ip_outer = mtod(mb_first, struct ip *);
2456 	*ip_outer = pim_encap_iphdr;
2457 	ip_outer->ip_len = htons(len + sizeof(pim_encap_iphdr) +
2458 			sizeof(pim_encap_pimhdr));
2459 	ip_outer->ip_src = V_viftable[vifi].v_lcl_addr;
2460 	ip_outer->ip_dst = rt->mfc_rp;
2461 	/*
2462 	 * Copy the inner header TOS to the outer header, and take care of the
2463 	 * IP_DF bit.
2464 	 */
2465 	ip_outer->ip_tos = ip->ip_tos;
2466 	if (ip->ip_off & htons(IP_DF))
2467 		ip_outer->ip_off |= htons(IP_DF);
2468 	ip_fillid(ip_outer, V_ip_random_id);
2469 	pimhdr = (struct pim_encap_pimhdr *)((caddr_t)ip_outer
2470 			+ sizeof(pim_encap_iphdr));
2471 	*pimhdr = pim_encap_pimhdr;
2472 	/* If the iif crosses a border, set the Border-bit */
2473 	if (rt->mfc_flags[vifi] & MRT_MFC_FLAGS_BORDER_VIF & V_mrt_api_config)
2474 		pimhdr->flags |= htonl(PIM_BORDER_REGISTER);
2475 
2476 	mb_first->m_data += sizeof(pim_encap_iphdr);
2477 	pimhdr->pim.pim_cksum = in_cksum(mb_first, sizeof(pim_encap_pimhdr));
2478 	mb_first->m_data -= sizeof(pim_encap_iphdr);
2479 
2480 	send_packet(vifp, mb_first);
2481 
2482 	/* Keep statistics */
2483 	PIMSTAT_INC(pims_snd_registers_msgs);
2484 	PIMSTAT_ADD(pims_snd_registers_bytes, len);
2485 
2486 	return 0;
2487 }
2488 
2489 /*
2490  * pim_encapcheck() is called by the encap4_input() path at runtime to
2491  * determine if a packet is for PIM; allowing PIM to be dynamically loaded
2492  * into the kernel.
2493  */
2494 static int
pim_encapcheck(const struct mbuf * m __unused,int off __unused,int proto __unused,void * arg __unused)2495 pim_encapcheck(const struct mbuf *m __unused, int off __unused,
2496     int proto __unused, void *arg __unused)
2497 {
2498 
2499 	KASSERT(proto == IPPROTO_PIM, ("not for IPPROTO_PIM"));
2500 	return (8);		/* claim the datagram. */
2501 }
2502 
2503 /*
2504  * PIM-SMv2 and PIM-DM messages processing.
2505  * Receives and verifies the PIM control messages, and passes them
2506  * up to the listening socket, using rip_input().
2507  * The only message with special processing is the PIM_REGISTER message
2508  * (used by PIM-SM): the PIM header is stripped off, and the inner packet
2509  * is passed to if_simloop().
2510  */
2511 static int
pim_input(struct mbuf * m,int off,int proto,void * arg __unused)2512 pim_input(struct mbuf *m, int off, int proto, void *arg __unused)
2513 {
2514 	struct ip *ip = mtod(m, struct ip *);
2515 	struct pim *pim;
2516 	int iphlen = off;
2517 	int minlen;
2518 	int datalen = ntohs(ip->ip_len) - iphlen;
2519 	int ip_tos;
2520 
2521 	/* Keep statistics */
2522 	PIMSTAT_INC(pims_rcv_total_msgs);
2523 	PIMSTAT_ADD(pims_rcv_total_bytes, datalen);
2524 
2525 	/*
2526 	 * Validate lengths
2527 	 */
2528 	if (datalen < PIM_MINLEN) {
2529 		PIMSTAT_INC(pims_rcv_tooshort);
2530 		CTR3(KTR_IPMF, "%s: short packet (%d) from 0x%08x",
2531 		    __func__, datalen, ntohl(ip->ip_src.s_addr));
2532 		m_freem(m);
2533 		return (IPPROTO_DONE);
2534 	}
2535 
2536 	/*
2537 	 * If the packet is at least as big as a REGISTER, go agead
2538 	 * and grab the PIM REGISTER header size, to avoid another
2539 	 * possible m_pullup() later.
2540 	 *
2541 	 * PIM_MINLEN       == pimhdr + u_int32_t == 4 + 4 = 8
2542 	 * PIM_REG_MINLEN   == pimhdr + reghdr + encap_iphdr == 4 + 4 + 20 = 28
2543 	 */
2544 	minlen = iphlen + (datalen >= PIM_REG_MINLEN ? PIM_REG_MINLEN : PIM_MINLEN);
2545 	/*
2546 	 * Get the IP and PIM headers in contiguous memory, and
2547 	 * possibly the PIM REGISTER header.
2548 	 */
2549 	if (m->m_len < minlen && (m = m_pullup(m, minlen)) == NULL) {
2550 		CTR1(KTR_IPMF, "%s: m_pullup() failed", __func__);
2551 		return (IPPROTO_DONE);
2552 	}
2553 
2554 	/* m_pullup() may have given us a new mbuf so reset ip. */
2555 	ip = mtod(m, struct ip *);
2556 	ip_tos = ip->ip_tos;
2557 
2558 	/* adjust mbuf to point to the PIM header */
2559 	m->m_data += iphlen;
2560 	m->m_len  -= iphlen;
2561 	pim = mtod(m, struct pim *);
2562 
2563 	/*
2564 	 * Validate checksum. If PIM REGISTER, exclude the data packet.
2565 	 *
2566 	 * XXX: some older PIMv2 implementations don't make this distinction,
2567 	 * so for compatibility reason perform the checksum over part of the
2568 	 * message, and if error, then over the whole message.
2569 	 */
2570 	if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER && in_cksum(m, PIM_MINLEN) == 0) {
2571 		/* do nothing, checksum okay */
2572 	} else if (in_cksum(m, datalen)) {
2573 		PIMSTAT_INC(pims_rcv_badsum);
2574 		CTR1(KTR_IPMF, "%s: invalid checksum", __func__);
2575 		m_freem(m);
2576 		return (IPPROTO_DONE);
2577 	}
2578 
2579 	/* PIM version check */
2580 	if (PIM_VT_V(pim->pim_vt) < PIM_VERSION) {
2581 		PIMSTAT_INC(pims_rcv_badversion);
2582 		CTR3(KTR_IPMF, "%s: bad version %d expect %d", __func__,
2583 		    (int)PIM_VT_V(pim->pim_vt), PIM_VERSION);
2584 		m_freem(m);
2585 		return (IPPROTO_DONE);
2586 	}
2587 
2588 	/* restore mbuf back to the outer IP */
2589 	m->m_data -= iphlen;
2590 	m->m_len  += iphlen;
2591 
2592 	if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER) {
2593 		/*
2594 		 * Since this is a REGISTER, we'll make a copy of the register
2595 		 * headers ip + pim + u_int32 + encap_ip, to be passed up to the
2596 		 * routing daemon.
2597 		 */
2598 		struct sockaddr_in dst = { sizeof(dst), AF_INET };
2599 		struct mbuf *mcp;
2600 		struct ip *encap_ip;
2601 		u_int32_t *reghdr;
2602 		struct ifnet *vifp;
2603 
2604 		MRW_RLOCK();
2605 		if ((V_reg_vif_num >= V_numvifs) || (V_reg_vif_num == VIFI_INVALID)) {
2606 			MRW_RUNLOCK();
2607 			CTR2(KTR_IPMF, "%s: register vif not set: %d", __func__,
2608 			    (int)V_reg_vif_num);
2609 			m_freem(m);
2610 			return (IPPROTO_DONE);
2611 		}
2612 		/* XXX need refcnt? */
2613 		vifp = V_viftable[V_reg_vif_num].v_ifp;
2614 		MRW_RUNLOCK();
2615 
2616 		/*
2617 		 * Validate length
2618 		 */
2619 		if (datalen < PIM_REG_MINLEN) {
2620 			PIMSTAT_INC(pims_rcv_tooshort);
2621 			PIMSTAT_INC(pims_rcv_badregisters);
2622 			CTR1(KTR_IPMF, "%s: register packet size too small", __func__);
2623 			m_freem(m);
2624 			return (IPPROTO_DONE);
2625 		}
2626 
2627 		reghdr = (u_int32_t *)(pim + 1);
2628 		encap_ip = (struct ip *)(reghdr + 1);
2629 
2630 		CTR3(KTR_IPMF, "%s: register: encap ip src 0x%08x len %d",
2631 		    __func__, ntohl(encap_ip->ip_src.s_addr),
2632 		    ntohs(encap_ip->ip_len));
2633 
2634 		/* verify the version number of the inner packet */
2635 		if (encap_ip->ip_v != IPVERSION) {
2636 			PIMSTAT_INC(pims_rcv_badregisters);
2637 			CTR1(KTR_IPMF, "%s: bad encap ip version", __func__);
2638 			m_freem(m);
2639 			return (IPPROTO_DONE);
2640 		}
2641 
2642 		/* verify the inner packet is destined to a mcast group */
2643 		if (!IN_MULTICAST(ntohl(encap_ip->ip_dst.s_addr))) {
2644 			PIMSTAT_INC(pims_rcv_badregisters);
2645 			CTR2(KTR_IPMF, "%s: bad encap ip dest 0x%08x", __func__,
2646 			    ntohl(encap_ip->ip_dst.s_addr));
2647 			m_freem(m);
2648 			return (IPPROTO_DONE);
2649 		}
2650 
2651 		/* If a NULL_REGISTER, pass it to the daemon */
2652 		if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
2653 			goto pim_input_to_daemon;
2654 
2655 		/*
2656 		 * Copy the TOS from the outer IP header to the inner IP header.
2657 		 */
2658 		if (encap_ip->ip_tos != ip_tos) {
2659 			/* Outer TOS -> inner TOS */
2660 			encap_ip->ip_tos = ip_tos;
2661 			/* Recompute the inner header checksum. Sigh... */
2662 
2663 			/* adjust mbuf to point to the inner IP header */
2664 			m->m_data += (iphlen + PIM_MINLEN);
2665 			m->m_len  -= (iphlen + PIM_MINLEN);
2666 
2667 			encap_ip->ip_sum = 0;
2668 			encap_ip->ip_sum = in_cksum(m, encap_ip->ip_hl << 2);
2669 
2670 			/* restore mbuf to point back to the outer IP header */
2671 			m->m_data -= (iphlen + PIM_MINLEN);
2672 			m->m_len  += (iphlen + PIM_MINLEN);
2673 		}
2674 
2675 		/*
2676 		 * Decapsulate the inner IP packet and loopback to forward it
2677 		 * as a normal multicast packet. Also, make a copy of the
2678 		 *     outer_iphdr + pimhdr + reghdr + encap_iphdr
2679 		 * to pass to the daemon later, so it can take the appropriate
2680 		 * actions (e.g., send back PIM_REGISTER_STOP).
2681 		 * XXX: here m->m_data points to the outer IP header.
2682 		 */
2683 		mcp = m_copym(m, 0, iphlen + PIM_REG_MINLEN, M_NOWAIT);
2684 		if (mcp == NULL) {
2685 			CTR1(KTR_IPMF, "%s: m_copym() failed", __func__);
2686 			m_freem(m);
2687 			return (IPPROTO_DONE);
2688 		}
2689 
2690 		/* Keep statistics */
2691 		/* XXX: registers_bytes include only the encap. mcast pkt */
2692 		PIMSTAT_INC(pims_rcv_registers_msgs);
2693 		PIMSTAT_ADD(pims_rcv_registers_bytes, ntohs(encap_ip->ip_len));
2694 
2695 		/*
2696 		 * forward the inner ip packet; point m_data at the inner ip.
2697 		 */
2698 		m_adj(m, iphlen + PIM_MINLEN);
2699 
2700 		CTR4(KTR_IPMF,
2701 		    "%s: forward decap'd REGISTER: src %lx dst %lx vif %d",
2702 		    __func__,
2703 		    (u_long)ntohl(encap_ip->ip_src.s_addr),
2704 		    (u_long)ntohl(encap_ip->ip_dst.s_addr),
2705 		    (int)V_reg_vif_num);
2706 
2707 		/* NB: vifp was collected above; can it change on us? */
2708 		if_simloop(vifp, m, dst.sin_family, 0);
2709 
2710 		/* prepare the register head to send to the mrouting daemon */
2711 		m = mcp;
2712 	}
2713 
2714 pim_input_to_daemon:
2715 	/*
2716 	 * Pass the PIM message up to the daemon; if it is a Register message,
2717 	 * pass the 'head' only up to the daemon. This includes the
2718 	 * outer IP header, PIM header, PIM-Register header and the
2719 	 * inner IP header.
2720 	 * XXX: the outer IP header pkt size of a Register is not adjust to
2721 	 * reflect the fact that the inner multicast data is truncated.
2722 	 */
2723 	return (rip_input(&m, &off, proto));
2724 }
2725 
2726 static int
sysctl_mfctable(SYSCTL_HANDLER_ARGS)2727 sysctl_mfctable(SYSCTL_HANDLER_ARGS)
2728 {
2729 	struct mfc	*rt;
2730 	int		 error, i;
2731 
2732 	if (req->newptr)
2733 		return (EPERM);
2734 	if (V_mfchashtbl == NULL)	/* XXX unlocked */
2735 		return (0);
2736 	error = sysctl_wire_old_buffer(req, 0);
2737 	if (error)
2738 		return (error);
2739 
2740 	MRW_RLOCK();
2741 	if (V_mfchashtbl == NULL)
2742 		goto out_locked;
2743 
2744 	for (i = 0; i < mfchashsize; i++) {
2745 		LIST_FOREACH(rt, &V_mfchashtbl[i], mfc_hash) {
2746 			error = SYSCTL_OUT(req, rt, sizeof(struct mfc));
2747 			if (error)
2748 				goto out_locked;
2749 		}
2750 	}
2751 out_locked:
2752 	MRW_RUNLOCK();
2753 	return (error);
2754 }
2755 
2756 static SYSCTL_NODE(_net_inet_ip, OID_AUTO, mfctable,
2757     CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_mfctable,
2758     "IPv4 Multicast Forwarding Table "
2759     "(struct *mfc[mfchashsize], netinet/ip_mroute.h)");
2760 
2761 static int
sysctl_viflist(SYSCTL_HANDLER_ARGS)2762 sysctl_viflist(SYSCTL_HANDLER_ARGS)
2763 {
2764 	int error, i;
2765 
2766 	if (req->newptr)
2767 		return (EPERM);
2768 	if (V_viftable == NULL)		/* XXX unlocked */
2769 		return (0);
2770 	error = sysctl_wire_old_buffer(req, MROUTE_VIF_SYSCTL_LEN * MAXVIFS);
2771 	if (error)
2772 		return (error);
2773 
2774 	MRW_RLOCK();
2775 	/* Copy out user-visible portion of vif entry. */
2776 	for (i = 0; i < MAXVIFS; i++) {
2777 		error = SYSCTL_OUT(req, &V_viftable[i], MROUTE_VIF_SYSCTL_LEN);
2778 		if (error)
2779 			break;
2780 	}
2781 	MRW_RUNLOCK();
2782 	return (error);
2783 }
2784 
2785 SYSCTL_PROC(_net_inet_ip, OID_AUTO, viftable,
2786     CTLTYPE_OPAQUE | CTLFLAG_VNET | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
2787     sysctl_viflist, "S,vif[MAXVIFS]",
2788     "IPv4 Multicast Interfaces (struct vif[MAXVIFS], netinet/ip_mroute.h)");
2789 
2790 static void
vnet_mroute_init(const void * unused __unused)2791 vnet_mroute_init(const void *unused __unused)
2792 {
2793 
2794 	V_nexpire = malloc(mfchashsize, M_MRTABLE, M_WAITOK|M_ZERO);
2795 
2796 	V_viftable = mallocarray(MAXVIFS, sizeof(*V_viftable),
2797 	    M_MRTABLE, M_WAITOK|M_ZERO);
2798 
2799 	callout_init_rw(&V_expire_upcalls_ch, &mrouter_lock, 0);
2800 	callout_init_rw(&V_bw_upcalls_ch, &mrouter_lock, 0);
2801 
2802 	/* Prepare taskqueue */
2803 	V_task_queue = taskqueue_create_fast("ip_mroute_tskq", M_NOWAIT,
2804 		    taskqueue_thread_enqueue, &V_task_queue);
2805 	taskqueue_start_threads(&V_task_queue, 1, PI_NET, "ip_mroute_tskq task");
2806 }
2807 
2808 VNET_SYSINIT(vnet_mroute_init, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mroute_init,
2809 	NULL);
2810 
2811 static void
vnet_mroute_uninit(const void * unused __unused)2812 vnet_mroute_uninit(const void *unused __unused)
2813 {
2814 
2815 	/* Taskqueue should be cancelled and drained before freeing */
2816 	taskqueue_free(V_task_queue);
2817 
2818 	free(V_viftable, M_MRTABLE);
2819 	free(V_nexpire, M_MRTABLE);
2820 	V_nexpire = NULL;
2821 }
2822 
2823 VNET_SYSUNINIT(vnet_mroute_uninit, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE,
2824     vnet_mroute_uninit, NULL);
2825 
2826 static int
ip_mroute_modevent(module_t mod,int type,void * unused)2827 ip_mroute_modevent(module_t mod, int type, void *unused)
2828 {
2829 
2830 	switch (type) {
2831 	case MOD_LOAD:
2832 		MRW_TEARDOWN_LOCK_INIT();
2833 		MRW_LOCK_INIT();
2834 
2835 		if_detach_event_tag = EVENTHANDLER_REGISTER(ifnet_departure_event,
2836 		    if_detached_event, NULL, EVENTHANDLER_PRI_ANY);
2837 		if (if_detach_event_tag == NULL) {
2838 			printf("ip_mroute: unable to register "
2839 					"ifnet_departure_event handler\n");
2840 			MRW_LOCK_DESTROY();
2841 			return (EINVAL);
2842 		}
2843 
2844 		if (!powerof2(mfchashsize)) {
2845 			printf("WARNING: %s not a power of 2; using default\n",
2846 					"net.inet.ip.mfchashsize");
2847 			mfchashsize = MFCHASHSIZE;
2848 		}
2849 
2850 		pim_encap_cookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
2851 
2852 		ip_mcast_src = X_ip_mcast_src;
2853 		ip_mforward = X_ip_mforward;
2854 		ip_mrouter_done = X_ip_mrouter_done;
2855 		ip_mrouter_get = X_ip_mrouter_get;
2856 		ip_mrouter_set = X_ip_mrouter_set;
2857 
2858 		ip_rsvp_force_done = X_ip_rsvp_force_done;
2859 		ip_rsvp_vif = X_ip_rsvp_vif;
2860 
2861 		legal_vif_num = X_legal_vif_num;
2862 		mrt_ioctl = X_mrt_ioctl;
2863 		rsvp_input_p = X_rsvp_input;
2864 		break;
2865 
2866 	case MOD_UNLOAD:
2867 		/*
2868 		 * Typically module unload happens after the user-level
2869 		 * process has shutdown the kernel services (the check
2870 		 * below insures someone can't just yank the module out
2871 		 * from under a running process).  But if the module is
2872 		 * just loaded and then unloaded w/o starting up a user
2873 		 * process we still need to cleanup.
2874 		 */
2875 		MRW_WLOCK();
2876 		if (ip_mrouter_cnt != 0) {
2877 			MRW_WUNLOCK();
2878 			return (EINVAL);
2879 		}
2880 		ip_mrouter_unloading = 1;
2881 		MRW_WUNLOCK();
2882 
2883 		EVENTHANDLER_DEREGISTER(ifnet_departure_event, if_detach_event_tag);
2884 
2885 		if (pim_encap_cookie) {
2886 			ip_encap_detach(pim_encap_cookie);
2887 			pim_encap_cookie = NULL;
2888 		}
2889 
2890 		ip_mcast_src = NULL;
2891 		ip_mforward = NULL;
2892 		ip_mrouter_done = NULL;
2893 		ip_mrouter_get = NULL;
2894 		ip_mrouter_set = NULL;
2895 
2896 		ip_rsvp_force_done = NULL;
2897 		ip_rsvp_vif = NULL;
2898 
2899 		legal_vif_num = NULL;
2900 		mrt_ioctl = NULL;
2901 		rsvp_input_p = NULL;
2902 
2903 		MRW_LOCK_DESTROY();
2904 		MRW_TEARDOWN_LOCK_DESTROY();
2905 		break;
2906 
2907 	default:
2908 		return EOPNOTSUPP;
2909 	}
2910 	return 0;
2911 }
2912 
2913 static moduledata_t ip_mroutemod = {
2914 	"ip_mroute",
2915 	ip_mroute_modevent,
2916 	0
2917 };
2918 
2919 DECLARE_MODULE(ip_mroute, ip_mroutemod, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE);
2920