xref: /netbsd-src/sys/netinet/ip_mroute.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: ip_mroute.c,v 1.130 2014/06/05 23:48:16 rmind Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *      The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Stephen Deering of Stanford University.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *      @(#)ip_mroute.c 8.2 (Berkeley) 11/15/93
35  */
36 
37 /*
38  * Copyright (c) 1989 Stephen Deering
39  *
40  * This code is derived from software contributed to Berkeley by
41  * Stephen Deering of Stanford University.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *      This product includes software developed by the University of
54  *      California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  *      @(#)ip_mroute.c 8.2 (Berkeley) 11/15/93
72  */
73 
74 /*
75  * IP multicast forwarding procedures
76  *
77  * Written by David Waitzman, BBN Labs, August 1988.
78  * Modified by Steve Deering, Stanford, February 1989.
79  * Modified by Mark J. Steiglitz, Stanford, May, 1991
80  * Modified by Van Jacobson, LBL, January 1993
81  * Modified by Ajit Thyagarajan, PARC, August 1993
82  * Modified by Bill Fenner, PARC, April 1994
83  * Modified by Charles M. Hannum, NetBSD, May 1995.
84  * Modified by Ahmed Helmy, SGI, June 1996
85  * Modified by George Edmond Eddy (Rusty), ISI, February 1998
86  * Modified by Pavlin Radoslavov, USC/ISI, May 1998, August 1999, October 2000
87  * Modified by Hitoshi Asaeda, WIDE, August 2000
88  * Modified by Pavlin Radoslavov, ICSI, October 2002
89  *
90  * MROUTING Revision: 1.2
91  * and PIM-SMv2 and PIM-DM support, advanced API support,
92  * bandwidth metering and signaling
93  */
94 
95 #include <sys/cdefs.h>
96 __KERNEL_RCSID(0, "$NetBSD: ip_mroute.c,v 1.130 2014/06/05 23:48:16 rmind Exp $");
97 
98 #include "opt_inet.h"
99 #include "opt_ipsec.h"
100 #include "opt_pim.h"
101 
102 #ifdef PIM
103 #define _PIM_VT 1
104 #endif
105 
106 #include <sys/param.h>
107 #include <sys/systm.h>
108 #include <sys/callout.h>
109 #include <sys/mbuf.h>
110 #include <sys/socket.h>
111 #include <sys/socketvar.h>
112 #include <sys/protosw.h>
113 #include <sys/errno.h>
114 #include <sys/time.h>
115 #include <sys/kernel.h>
116 #include <sys/kmem.h>
117 #include <sys/ioctl.h>
118 #include <sys/syslog.h>
119 
120 #include <net/if.h>
121 #include <net/route.h>
122 #include <net/raw_cb.h>
123 
124 #include <netinet/in.h>
125 #include <netinet/in_var.h>
126 #include <netinet/in_systm.h>
127 #include <netinet/ip.h>
128 #include <netinet/ip_var.h>
129 #include <netinet/in_pcb.h>
130 #include <netinet/udp.h>
131 #include <netinet/igmp.h>
132 #include <netinet/igmp_var.h>
133 #include <netinet/ip_mroute.h>
134 #ifdef PIM
135 #include <netinet/pim.h>
136 #include <netinet/pim_var.h>
137 #endif
138 #include <netinet/ip_encap.h>
139 
140 #ifdef IPSEC
141 #include <netipsec/ipsec.h>
142 #include <netipsec/key.h>
143 #endif
144 
145 #define IP_MULTICASTOPTS 0
146 #define	M_PULLUP(m, len)						 \
147 	do {								 \
148 		if ((m) && ((m)->m_flags & M_EXT || (m)->m_len < (len))) \
149 			(m) = m_pullup((m), (len));			 \
150 	} while (/*CONSTCOND*/ 0)
151 
152 /*
153  * Globals.  All but ip_mrouter and ip_mrtproto could be static,
154  * except for netstat or debugging purposes.
155  */
156 struct socket  *ip_mrouter  = NULL;
157 int		ip_mrtproto = IGMP_DVMRP;    /* for netstat only */
158 
159 #define NO_RTE_FOUND 	0x1
160 #define RTE_FOUND	0x2
161 
162 #define	MFCHASH(a, g)							\
163 	((((a).s_addr >> 20) ^ ((a).s_addr >> 10) ^ (a).s_addr ^	\
164 	  ((g).s_addr >> 20) ^ ((g).s_addr >> 10) ^ (g).s_addr) & mfchash)
165 LIST_HEAD(mfchashhdr, mfc) *mfchashtbl;
166 u_long	mfchash;
167 
168 u_char		nexpire[MFCTBLSIZ];
169 struct vif	viftable[MAXVIFS];
170 struct mrtstat	mrtstat;
171 u_int		mrtdebug = 0;	  /* debug level 	*/
172 #define		DEBUG_MFC	0x02
173 #define		DEBUG_FORWARD	0x04
174 #define		DEBUG_EXPIRE	0x08
175 #define		DEBUG_XMIT	0x10
176 #define		DEBUG_PIM	0x20
177 
178 #define		VIFI_INVALID	((vifi_t) -1)
179 
180 u_int       	tbfdebug = 0;     /* tbf debug level 	*/
181 #ifdef RSVP_ISI
182 u_int		rsvpdebug = 0;	  /* rsvp debug level   */
183 extern struct socket *ip_rsvpd;
184 extern int rsvp_on;
185 #endif /* RSVP_ISI */
186 
187 /* vif attachment using sys/netinet/ip_encap.c */
188 static void vif_input(struct mbuf *, ...);
189 static int vif_encapcheck(struct mbuf *, int, int, void *);
190 
191 static const struct protosw vif_protosw = {
192 	.pr_type	= SOCK_RAW,
193 	.pr_domain	= &inetdomain,
194 	.pr_protocol	= IPPROTO_IPV4,
195 	.pr_flags	= PR_ATOMIC|PR_ADDR,
196 	.pr_input	= vif_input,
197 	.pr_output	= rip_output,
198 	.pr_ctloutput	= rip_ctloutput,
199 	.pr_usrreqs	= &rip_usrreqs,
200 };
201 
202 #define		EXPIRE_TIMEOUT	(hz / 4)	/* 4x / second */
203 #define		UPCALL_EXPIRE	6		/* number of timeouts */
204 
205 /*
206  * Define the token bucket filter structures
207  */
208 
209 #define		TBF_REPROCESS	(hz / 100)	/* 100x / second */
210 
211 static int get_sg_cnt(struct sioc_sg_req *);
212 static int get_vif_cnt(struct sioc_vif_req *);
213 static int ip_mrouter_init(struct socket *, int);
214 static int set_assert(int);
215 static int add_vif(struct vifctl *);
216 static int del_vif(vifi_t *);
217 static void update_mfc_params(struct mfc *, struct mfcctl2 *);
218 static void init_mfc_params(struct mfc *, struct mfcctl2 *);
219 static void expire_mfc(struct mfc *);
220 static int add_mfc(struct sockopt *);
221 #ifdef UPCALL_TIMING
222 static void collate(struct timeval *);
223 #endif
224 static int del_mfc(struct sockopt *);
225 static int set_api_config(struct sockopt *); /* chose API capabilities */
226 static int socket_send(struct socket *, struct mbuf *, struct sockaddr_in *);
227 static void expire_upcalls(void *);
228 #ifdef RSVP_ISI
229 static int ip_mdq(struct mbuf *, struct ifnet *, struct mfc *, vifi_t);
230 #else
231 static int ip_mdq(struct mbuf *, struct ifnet *, struct mfc *);
232 #endif
233 static void phyint_send(struct ip *, struct vif *, struct mbuf *);
234 static void encap_send(struct ip *, struct vif *, struct mbuf *);
235 static void tbf_control(struct vif *, struct mbuf *, struct ip *, u_int32_t);
236 static void tbf_queue(struct vif *, struct mbuf *);
237 static void tbf_process_q(struct vif *);
238 static void tbf_reprocess_q(void *);
239 static int tbf_dq_sel(struct vif *, struct ip *);
240 static void tbf_send_packet(struct vif *, struct mbuf *);
241 static void tbf_update_tokens(struct vif *);
242 static int priority(struct vif *, struct ip *);
243 
244 /*
245  * Bandwidth monitoring
246  */
247 static void free_bw_list(struct bw_meter *);
248 static int add_bw_upcall(struct bw_upcall *);
249 static int del_bw_upcall(struct bw_upcall *);
250 static void bw_meter_receive_packet(struct bw_meter *, int , struct timeval *);
251 static void bw_meter_prepare_upcall(struct bw_meter *, struct timeval *);
252 static void bw_upcalls_send(void);
253 static void schedule_bw_meter(struct bw_meter *, struct timeval *);
254 static void unschedule_bw_meter(struct bw_meter *);
255 static void bw_meter_process(void);
256 static void expire_bw_upcalls_send(void *);
257 static void expire_bw_meter_process(void *);
258 
259 #ifdef PIM
260 static int pim_register_send(struct ip *, struct vif *,
261 		struct mbuf *, struct mfc *);
262 static int pim_register_send_rp(struct ip *, struct vif *,
263 		struct mbuf *, struct mfc *);
264 static int pim_register_send_upcall(struct ip *, struct vif *,
265 		struct mbuf *, struct mfc *);
266 static struct mbuf *pim_register_prepare(struct ip *, struct mbuf *);
267 #endif
268 
269 /*
270  * 'Interfaces' associated with decapsulator (so we can tell
271  * packets that went through it from ones that get reflected
272  * by a broken gateway).  These interfaces are never linked into
273  * the system ifnet list & no routes point to them.  I.e., packets
274  * can't be sent this way.  They only exist as a placeholder for
275  * multicast source verification.
276  */
277 #if 0
278 struct ifnet multicast_decap_if[MAXVIFS];
279 #endif
280 
281 #define	ENCAP_TTL	64
282 #define	ENCAP_PROTO	IPPROTO_IPIP	/* 4 */
283 
284 /* prototype IP hdr for encapsulated packets */
285 struct ip multicast_encap_iphdr = {
286 	.ip_hl = sizeof(struct ip) >> 2,
287 	.ip_v = IPVERSION,
288 	.ip_len = sizeof(struct ip),
289 	.ip_ttl = ENCAP_TTL,
290 	.ip_p = ENCAP_PROTO,
291 };
292 
293 /*
294  * Bandwidth meter variables and constants
295  */
296 
297 /*
298  * Pending timeouts are stored in a hash table, the key being the
299  * expiration time. Periodically, the entries are analysed and processed.
300  */
301 #define BW_METER_BUCKETS	1024
302 static struct bw_meter *bw_meter_timers[BW_METER_BUCKETS];
303 struct callout bw_meter_ch;
304 #define BW_METER_PERIOD (hz)		/* periodical handling of bw meters */
305 
306 /*
307  * Pending upcalls are stored in a vector which is flushed when
308  * full, or periodically
309  */
310 static struct bw_upcall	bw_upcalls[BW_UPCALLS_MAX];
311 static u_int	bw_upcalls_n; /* # of pending upcalls */
312 struct callout	bw_upcalls_ch;
313 #define BW_UPCALLS_PERIOD (hz)		/* periodical flush of bw upcalls */
314 
315 #ifdef PIM
316 struct pimstat pimstat;
317 
318 /*
319  * Note: the PIM Register encapsulation adds the following in front of a
320  * data packet:
321  *
322  * struct pim_encap_hdr {
323  *    struct ip ip;
324  *    struct pim_encap_pimhdr  pim;
325  * }
326  *
327  */
328 
329 struct pim_encap_pimhdr {
330 	struct pim pim;
331 	uint32_t   flags;
332 };
333 
334 static struct ip pim_encap_iphdr = {
335 	.ip_v = IPVERSION,
336 	.ip_hl = sizeof(struct ip) >> 2,
337 	.ip_len = sizeof(struct ip),
338 	.ip_ttl = ENCAP_TTL,
339 	.ip_p = IPPROTO_PIM,
340 };
341 
342 static struct pim_encap_pimhdr pim_encap_pimhdr = {
343     {
344 	PIM_MAKE_VT(PIM_VERSION, PIM_REGISTER), /* PIM vers and message type */
345 	0,			/* reserved */
346 	0,			/* checksum */
347     },
348     0				/* flags */
349 };
350 
351 static struct ifnet multicast_register_if;
352 static vifi_t reg_vif_num = VIFI_INVALID;
353 #endif /* PIM */
354 
355 
356 /*
357  * Private variables.
358  */
359 static vifi_t	   numvifs = 0;
360 
361 static struct callout expire_upcalls_ch;
362 
363 /*
364  * whether or not special PIM assert processing is enabled.
365  */
366 static int pim_assert;
367 /*
368  * Rate limit for assert notification messages, in usec
369  */
370 #define ASSERT_MSG_TIME		3000000
371 
372 /*
373  * Kernel multicast routing API capabilities and setup.
374  * If more API capabilities are added to the kernel, they should be
375  * recorded in `mrt_api_support'.
376  */
377 static const u_int32_t mrt_api_support = (MRT_MFC_FLAGS_DISABLE_WRONGVIF |
378 					  MRT_MFC_FLAGS_BORDER_VIF |
379 					  MRT_MFC_RP |
380 					  MRT_MFC_BW_UPCALL);
381 static u_int32_t mrt_api_config = 0;
382 
383 /*
384  * Find a route for a given origin IP address and Multicast group address
385  * Type of service parameter to be added in the future!!!
386  * Statistics are updated by the caller if needed
387  * (mrtstat.mrts_mfc_lookups and mrtstat.mrts_mfc_misses)
388  */
389 static struct mfc *
390 mfc_find(struct in_addr *o, struct in_addr *g)
391 {
392 	struct mfc *rt;
393 
394 	LIST_FOREACH(rt, &mfchashtbl[MFCHASH(*o, *g)], mfc_hash) {
395 		if (in_hosteq(rt->mfc_origin, *o) &&
396 		    in_hosteq(rt->mfc_mcastgrp, *g) &&
397 		    (rt->mfc_stall == NULL))
398 			break;
399 	}
400 
401 	return (rt);
402 }
403 
404 /*
405  * Macros to compute elapsed time efficiently
406  * Borrowed from Van Jacobson's scheduling code
407  */
408 #define TV_DELTA(a, b, delta) do {					\
409 	int xxs;							\
410 	delta = (a).tv_usec - (b).tv_usec;				\
411 	xxs = (a).tv_sec - (b).tv_sec;					\
412 	switch (xxs) {							\
413 	case 2:								\
414 		delta += 1000000;					\
415 		/* fall through */					\
416 	case 1:								\
417 		delta += 1000000;					\
418 		/* fall through */					\
419 	case 0:								\
420 		break;							\
421 	default:							\
422 		delta += (1000000 * xxs);				\
423 		break;							\
424 	}								\
425 } while (/*CONSTCOND*/ 0)
426 
427 #ifdef UPCALL_TIMING
428 u_int32_t upcall_data[51];
429 #endif /* UPCALL_TIMING */
430 
431 /*
432  * Handle MRT setsockopt commands to modify the multicast routing tables.
433  */
434 int
435 ip_mrouter_set(struct socket *so, struct sockopt *sopt)
436 {
437 	int error;
438 	int optval;
439 	struct vifctl vifc;
440 	vifi_t vifi;
441 	struct bw_upcall bwuc;
442 
443 	if (sopt->sopt_name != MRT_INIT && so != ip_mrouter)
444 		error = ENOPROTOOPT;
445 	else {
446 		switch (sopt->sopt_name) {
447 		case MRT_INIT:
448 			error = sockopt_getint(sopt, &optval);
449 			if (error)
450 				break;
451 
452 			error = ip_mrouter_init(so, optval);
453 			break;
454 		case MRT_DONE:
455 			error = ip_mrouter_done();
456 			break;
457 		case MRT_ADD_VIF:
458 			error = sockopt_get(sopt, &vifc, sizeof(vifc));
459 			if (error)
460 				break;
461 			error = add_vif(&vifc);
462 			break;
463 		case MRT_DEL_VIF:
464 			error = sockopt_get(sopt, &vifi, sizeof(vifi));
465 			if (error)
466 				break;
467 			error = del_vif(&vifi);
468 			break;
469 		case MRT_ADD_MFC:
470 			error = add_mfc(sopt);
471 			break;
472 		case MRT_DEL_MFC:
473 			error = del_mfc(sopt);
474 			break;
475 		case MRT_ASSERT:
476 			error = sockopt_getint(sopt, &optval);
477 			if (error)
478 				break;
479 			error = set_assert(optval);
480 			break;
481 		case MRT_API_CONFIG:
482 			error = set_api_config(sopt);
483 			break;
484 		case MRT_ADD_BW_UPCALL:
485 			error = sockopt_get(sopt, &bwuc, sizeof(bwuc));
486 			if (error)
487 				break;
488 			error = add_bw_upcall(&bwuc);
489 			break;
490 		case MRT_DEL_BW_UPCALL:
491 			error = sockopt_get(sopt, &bwuc, sizeof(bwuc));
492 			if (error)
493 				break;
494 			error = del_bw_upcall(&bwuc);
495 			break;
496 		default:
497 			error = ENOPROTOOPT;
498 			break;
499 		}
500 	}
501 	return (error);
502 }
503 
504 /*
505  * Handle MRT getsockopt commands
506  */
507 int
508 ip_mrouter_get(struct socket *so, struct sockopt *sopt)
509 {
510 	int error;
511 
512 	if (so != ip_mrouter)
513 		error = ENOPROTOOPT;
514 	else {
515 		switch (sopt->sopt_name) {
516 		case MRT_VERSION:
517 			error = sockopt_setint(sopt, 0x0305); /* XXX !!!! */
518 			break;
519 		case MRT_ASSERT:
520 			error = sockopt_setint(sopt, pim_assert);
521 			break;
522 		case MRT_API_SUPPORT:
523 			error = sockopt_set(sopt, &mrt_api_support,
524 			    sizeof(mrt_api_support));
525 			break;
526 		case MRT_API_CONFIG:
527 			error = sockopt_set(sopt, &mrt_api_config,
528 			    sizeof(mrt_api_config));
529 			break;
530 		default:
531 			error = ENOPROTOOPT;
532 			break;
533 		}
534 	}
535 	return (error);
536 }
537 
538 /*
539  * Handle ioctl commands to obtain information from the cache
540  */
541 int
542 mrt_ioctl(struct socket *so, u_long cmd, void *data)
543 {
544 	int error;
545 
546 	if (so != ip_mrouter)
547 		error = EINVAL;
548 	else
549 		switch (cmd) {
550 		case SIOCGETVIFCNT:
551 			error = get_vif_cnt((struct sioc_vif_req *)data);
552 			break;
553 		case SIOCGETSGCNT:
554 			error = get_sg_cnt((struct sioc_sg_req *)data);
555 			break;
556 		default:
557 			error = EINVAL;
558 			break;
559 		}
560 
561 	return (error);
562 }
563 
564 /*
565  * returns the packet, byte, rpf-failure count for the source group provided
566  */
567 static int
568 get_sg_cnt(struct sioc_sg_req *req)
569 {
570 	int s;
571 	struct mfc *rt;
572 
573 	s = splsoftnet();
574 	rt = mfc_find(&req->src, &req->grp);
575 	if (rt == NULL) {
576 		splx(s);
577 		req->pktcnt = req->bytecnt = req->wrong_if = 0xffffffff;
578 		return (EADDRNOTAVAIL);
579 	}
580 	req->pktcnt = rt->mfc_pkt_cnt;
581 	req->bytecnt = rt->mfc_byte_cnt;
582 	req->wrong_if = rt->mfc_wrong_if;
583 	splx(s);
584 
585 	return (0);
586 }
587 
588 /*
589  * returns the input and output packet and byte counts on the vif provided
590  */
591 static int
592 get_vif_cnt(struct sioc_vif_req *req)
593 {
594 	vifi_t vifi = req->vifi;
595 
596 	if (vifi >= numvifs)
597 		return (EINVAL);
598 
599 	req->icount = viftable[vifi].v_pkt_in;
600 	req->ocount = viftable[vifi].v_pkt_out;
601 	req->ibytes = viftable[vifi].v_bytes_in;
602 	req->obytes = viftable[vifi].v_bytes_out;
603 
604 	return (0);
605 }
606 
607 /*
608  * Enable multicast routing
609  */
610 static int
611 ip_mrouter_init(struct socket *so, int v)
612 {
613 	if (mrtdebug)
614 		log(LOG_DEBUG,
615 		    "ip_mrouter_init: so_type = %d, pr_protocol = %d\n",
616 		    so->so_type, so->so_proto->pr_protocol);
617 
618 	if (so->so_type != SOCK_RAW ||
619 	    so->so_proto->pr_protocol != IPPROTO_IGMP)
620 		return (EOPNOTSUPP);
621 
622 	if (v != 1)
623 		return (EINVAL);
624 
625 	if (ip_mrouter != NULL)
626 		return (EADDRINUSE);
627 
628 	ip_mrouter = so;
629 
630 	mfchashtbl = hashinit(MFCTBLSIZ, HASH_LIST, true, &mfchash);
631 	memset((void *)nexpire, 0, sizeof(nexpire));
632 
633 	pim_assert = 0;
634 
635 	callout_init(&expire_upcalls_ch, 0);
636 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
637 		      expire_upcalls, NULL);
638 
639 	callout_init(&bw_upcalls_ch, 0);
640 	callout_reset(&bw_upcalls_ch, BW_UPCALLS_PERIOD,
641 		      expire_bw_upcalls_send, NULL);
642 
643 	callout_init(&bw_meter_ch, 0);
644 	callout_reset(&bw_meter_ch, BW_METER_PERIOD,
645 		      expire_bw_meter_process, NULL);
646 
647 	if (mrtdebug)
648 		log(LOG_DEBUG, "ip_mrouter_init\n");
649 
650 	return (0);
651 }
652 
653 /*
654  * Disable multicast routing
655  */
656 int
657 ip_mrouter_done(void)
658 {
659 	vifi_t vifi;
660 	struct vif *vifp;
661 	int i;
662 	int s;
663 
664 	s = splsoftnet();
665 
666 	/* Clear out all the vifs currently in use. */
667 	for (vifi = 0; vifi < numvifs; vifi++) {
668 		vifp = &viftable[vifi];
669 		if (!in_nullhost(vifp->v_lcl_addr))
670 			reset_vif(vifp);
671 	}
672 
673 	numvifs = 0;
674 	pim_assert = 0;
675 	mrt_api_config = 0;
676 
677 	callout_stop(&expire_upcalls_ch);
678 	callout_stop(&bw_upcalls_ch);
679 	callout_stop(&bw_meter_ch);
680 
681 	/*
682 	 * Free all multicast forwarding cache entries.
683 	 */
684 	for (i = 0; i < MFCTBLSIZ; i++) {
685 		struct mfc *rt, *nrt;
686 
687 		for (rt = LIST_FIRST(&mfchashtbl[i]); rt; rt = nrt) {
688 			nrt = LIST_NEXT(rt, mfc_hash);
689 
690 			expire_mfc(rt);
691 		}
692 	}
693 
694 	memset((void *)nexpire, 0, sizeof(nexpire));
695 	hashdone(mfchashtbl, HASH_LIST, mfchash);
696 	mfchashtbl = NULL;
697 
698 	bw_upcalls_n = 0;
699 	memset(bw_meter_timers, 0, sizeof(bw_meter_timers));
700 
701 	/* Reset de-encapsulation cache. */
702 
703 	ip_mrouter = NULL;
704 
705 	splx(s);
706 
707 	if (mrtdebug)
708 		log(LOG_DEBUG, "ip_mrouter_done\n");
709 
710 	return (0);
711 }
712 
713 void
714 ip_mrouter_detach(struct ifnet *ifp)
715 {
716 	int vifi, i;
717 	struct vif *vifp;
718 	struct mfc *rt;
719 	struct rtdetq *rte;
720 
721 	/* XXX not sure about side effect to userland routing daemon */
722 	for (vifi = 0; vifi < numvifs; vifi++) {
723 		vifp = &viftable[vifi];
724 		if (vifp->v_ifp == ifp)
725 			reset_vif(vifp);
726 	}
727 	for (i = 0; i < MFCTBLSIZ; i++) {
728 		if (nexpire[i] == 0)
729 			continue;
730 		LIST_FOREACH(rt, &mfchashtbl[i], mfc_hash) {
731 			for (rte = rt->mfc_stall; rte; rte = rte->next) {
732 				if (rte->ifp == ifp)
733 					rte->ifp = NULL;
734 			}
735 		}
736 	}
737 }
738 
739 /*
740  * Set PIM assert processing global
741  */
742 static int
743 set_assert(int i)
744 {
745 	pim_assert = !!i;
746 	return (0);
747 }
748 
749 /*
750  * Configure API capabilities
751  */
752 static int
753 set_api_config(struct sockopt *sopt)
754 {
755 	u_int32_t apival;
756 	int i, error;
757 
758 	/*
759 	 * We can set the API capabilities only if it is the first operation
760 	 * after MRT_INIT. I.e.:
761 	 *  - there are no vifs installed
762 	 *  - pim_assert is not enabled
763 	 *  - the MFC table is empty
764 	 */
765 	error = sockopt_get(sopt, &apival, sizeof(apival));
766 	if (error)
767 		return (error);
768 	if (numvifs > 0)
769 		return (EPERM);
770 	if (pim_assert)
771 		return (EPERM);
772 	for (i = 0; i < MFCTBLSIZ; i++) {
773 		if (LIST_FIRST(&mfchashtbl[i]) != NULL)
774 			return (EPERM);
775 	}
776 
777 	mrt_api_config = apival & mrt_api_support;
778 	return (0);
779 }
780 
781 /*
782  * Add a vif to the vif table
783  */
784 static int
785 add_vif(struct vifctl *vifcp)
786 {
787 	struct vif *vifp;
788 	struct ifaddr *ifa;
789 	struct ifnet *ifp;
790 	int error, s;
791 	struct sockaddr_in sin;
792 
793 	if (vifcp->vifc_vifi >= MAXVIFS)
794 		return (EINVAL);
795 	if (in_nullhost(vifcp->vifc_lcl_addr))
796 		return (EADDRNOTAVAIL);
797 
798 	vifp = &viftable[vifcp->vifc_vifi];
799 	if (!in_nullhost(vifp->v_lcl_addr))
800 		return (EADDRINUSE);
801 
802 	/* Find the interface with an address in AF_INET family. */
803 #ifdef PIM
804 	if (vifcp->vifc_flags & VIFF_REGISTER) {
805 		/*
806 		 * XXX: Because VIFF_REGISTER does not really need a valid
807 		 * local interface (e.g. it could be 127.0.0.2), we don't
808 		 * check its address.
809 		 */
810 	    ifp = NULL;
811 	} else
812 #endif
813 	{
814 		sockaddr_in_init(&sin, &vifcp->vifc_lcl_addr, 0);
815 		ifa = ifa_ifwithaddr(sintosa(&sin));
816 		if (ifa == NULL)
817 			return (EADDRNOTAVAIL);
818 		ifp = ifa->ifa_ifp;
819 	}
820 
821 	if (vifcp->vifc_flags & VIFF_TUNNEL) {
822 		if (vifcp->vifc_flags & VIFF_SRCRT) {
823 			log(LOG_ERR, "source routed tunnels not supported\n");
824 			return (EOPNOTSUPP);
825 		}
826 
827 		/* attach this vif to decapsulator dispatch table */
828 		/*
829 		 * XXX Use addresses in registration so that matching
830 		 * can be done with radix tree in decapsulator.  But,
831 		 * we need to check inner header for multicast, so
832 		 * this requires both radix tree lookup and then a
833 		 * function to check, and this is not supported yet.
834 		 */
835 		vifp->v_encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV4,
836 		    vif_encapcheck, &vif_protosw, vifp);
837 		if (!vifp->v_encap_cookie)
838 			return (EINVAL);
839 
840 		/* Create a fake encapsulation interface. */
841 		ifp = malloc(sizeof(*ifp), M_MRTABLE, M_WAITOK|M_ZERO);
842 		snprintf(ifp->if_xname, sizeof(ifp->if_xname),
843 			 "mdecap%d", vifcp->vifc_vifi);
844 
845 		/* Prepare cached route entry. */
846 		memset(&vifp->v_route, 0, sizeof(vifp->v_route));
847 #ifdef PIM
848 	} else if (vifcp->vifc_flags & VIFF_REGISTER) {
849 		ifp = &multicast_register_if;
850 		if (mrtdebug)
851 			log(LOG_DEBUG, "Adding a register vif, ifp: %p\n",
852 			    (void *)ifp);
853 		if (reg_vif_num == VIFI_INVALID) {
854 			memset(ifp, 0, sizeof(*ifp));
855 			snprintf(ifp->if_xname, sizeof(ifp->if_xname),
856 				 "register_vif");
857 			ifp->if_flags = IFF_LOOPBACK;
858 			memset(&vifp->v_route, 0, sizeof(vifp->v_route));
859 			reg_vif_num = vifcp->vifc_vifi;
860 		}
861 #endif
862 	} else {
863 		/* Make sure the interface supports multicast. */
864 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
865 			return (EOPNOTSUPP);
866 
867 		/* Enable promiscuous reception of all IP multicasts. */
868 		sockaddr_in_init(&sin, &zeroin_addr, 0);
869 		error = if_mcast_op(ifp, SIOCADDMULTI, sintosa(&sin));
870 		if (error)
871 			return (error);
872 	}
873 
874 	s = splsoftnet();
875 
876 	/* Define parameters for the tbf structure. */
877 	vifp->tbf_q = NULL;
878 	vifp->tbf_t = &vifp->tbf_q;
879 	microtime(&vifp->tbf_last_pkt_t);
880 	vifp->tbf_n_tok = 0;
881 	vifp->tbf_q_len = 0;
882 	vifp->tbf_max_q_len = MAXQSIZE;
883 
884 	vifp->v_flags = vifcp->vifc_flags;
885 	vifp->v_threshold = vifcp->vifc_threshold;
886 	/* scaling up here allows division by 1024 in critical code */
887 	vifp->v_rate_limit = vifcp->vifc_rate_limit * 1024 / 1000;
888 	vifp->v_lcl_addr = vifcp->vifc_lcl_addr;
889 	vifp->v_rmt_addr = vifcp->vifc_rmt_addr;
890 	vifp->v_ifp = ifp;
891 	/* Initialize per vif pkt counters. */
892 	vifp->v_pkt_in = 0;
893 	vifp->v_pkt_out = 0;
894 	vifp->v_bytes_in = 0;
895 	vifp->v_bytes_out = 0;
896 
897 	callout_init(&vifp->v_repq_ch, 0);
898 
899 #ifdef RSVP_ISI
900 	vifp->v_rsvp_on = 0;
901 	vifp->v_rsvpd = NULL;
902 #endif /* RSVP_ISI */
903 
904 	splx(s);
905 
906 	/* Adjust numvifs up if the vifi is higher than numvifs. */
907 	if (numvifs <= vifcp->vifc_vifi)
908 		numvifs = vifcp->vifc_vifi + 1;
909 
910 	if (mrtdebug)
911 		log(LOG_DEBUG, "add_vif #%d, lcladdr %x, %s %x, thresh %x, rate %d\n",
912 		    vifcp->vifc_vifi,
913 		    ntohl(vifcp->vifc_lcl_addr.s_addr),
914 		    (vifcp->vifc_flags & VIFF_TUNNEL) ? "rmtaddr" : "mask",
915 		    ntohl(vifcp->vifc_rmt_addr.s_addr),
916 		    vifcp->vifc_threshold,
917 		    vifcp->vifc_rate_limit);
918 
919 	return (0);
920 }
921 
922 void
923 reset_vif(struct vif *vifp)
924 {
925 	struct mbuf *m, *n;
926 	struct ifnet *ifp;
927 	struct sockaddr_in sin;
928 
929 	callout_stop(&vifp->v_repq_ch);
930 
931 	/* detach this vif from decapsulator dispatch table */
932 	encap_detach(vifp->v_encap_cookie);
933 	vifp->v_encap_cookie = NULL;
934 
935 	/*
936 	 * Free packets queued at the interface
937 	 */
938 	for (m = vifp->tbf_q; m != NULL; m = n) {
939 		n = m->m_nextpkt;
940 		m_freem(m);
941 	}
942 
943 	if (vifp->v_flags & VIFF_TUNNEL)
944 		free(vifp->v_ifp, M_MRTABLE);
945 	else if (vifp->v_flags & VIFF_REGISTER) {
946 #ifdef PIM
947 		reg_vif_num = VIFI_INVALID;
948 #endif
949 	} else {
950 		sockaddr_in_init(&sin, &zeroin_addr, 0);
951 		ifp = vifp->v_ifp;
952 		if_mcast_op(ifp, SIOCDELMULTI, sintosa(&sin));
953 	}
954 	memset((void *)vifp, 0, sizeof(*vifp));
955 }
956 
957 /*
958  * Delete a vif from the vif table
959  */
960 static int
961 del_vif(vifi_t *vifip)
962 {
963 	struct vif *vifp;
964 	vifi_t vifi;
965 	int s;
966 
967 	if (*vifip >= numvifs)
968 		return (EINVAL);
969 
970 	vifp = &viftable[*vifip];
971 	if (in_nullhost(vifp->v_lcl_addr))
972 		return (EADDRNOTAVAIL);
973 
974 	s = splsoftnet();
975 
976 	reset_vif(vifp);
977 
978 	/* Adjust numvifs down */
979 	for (vifi = numvifs; vifi > 0; vifi--)
980 		if (!in_nullhost(viftable[vifi - 1].v_lcl_addr))
981 			break;
982 	numvifs = vifi;
983 
984 	splx(s);
985 
986 	if (mrtdebug)
987 		log(LOG_DEBUG, "del_vif %d, numvifs %d\n", *vifip, numvifs);
988 
989 	return (0);
990 }
991 
992 /*
993  * update an mfc entry without resetting counters and S,G addresses.
994  */
995 static void
996 update_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp)
997 {
998 	int i;
999 
1000 	rt->mfc_parent = mfccp->mfcc_parent;
1001 	for (i = 0; i < numvifs; i++) {
1002 		rt->mfc_ttls[i] = mfccp->mfcc_ttls[i];
1003 		rt->mfc_flags[i] = mfccp->mfcc_flags[i] & mrt_api_config &
1004 			MRT_MFC_FLAGS_ALL;
1005 	}
1006 	/* set the RP address */
1007 	if (mrt_api_config & MRT_MFC_RP)
1008 		rt->mfc_rp = mfccp->mfcc_rp;
1009 	else
1010 		rt->mfc_rp = zeroin_addr;
1011 }
1012 
1013 /*
1014  * fully initialize an mfc entry from the parameter.
1015  */
1016 static void
1017 init_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp)
1018 {
1019 	rt->mfc_origin     = mfccp->mfcc_origin;
1020 	rt->mfc_mcastgrp   = mfccp->mfcc_mcastgrp;
1021 
1022 	update_mfc_params(rt, mfccp);
1023 
1024 	/* initialize pkt counters per src-grp */
1025 	rt->mfc_pkt_cnt    = 0;
1026 	rt->mfc_byte_cnt   = 0;
1027 	rt->mfc_wrong_if   = 0;
1028 	timerclear(&rt->mfc_last_assert);
1029 }
1030 
1031 static void
1032 expire_mfc(struct mfc *rt)
1033 {
1034 	struct rtdetq *rte, *nrte;
1035 
1036 	free_bw_list(rt->mfc_bw_meter);
1037 
1038 	for (rte = rt->mfc_stall; rte != NULL; rte = nrte) {
1039 		nrte = rte->next;
1040 		m_freem(rte->m);
1041 		free(rte, M_MRTABLE);
1042 	}
1043 
1044 	LIST_REMOVE(rt, mfc_hash);
1045 	free(rt, M_MRTABLE);
1046 }
1047 
1048 /*
1049  * Add an mfc entry
1050  */
1051 static int
1052 add_mfc(struct sockopt *sopt)
1053 {
1054 	struct mfcctl2 mfcctl2;
1055 	struct mfcctl2 *mfccp;
1056 	struct mfc *rt;
1057 	u_int32_t hash = 0;
1058 	struct rtdetq *rte, *nrte;
1059 	u_short nstl;
1060 	int s;
1061 	int error;
1062 
1063 	/*
1064 	 * select data size depending on API version.
1065 	 */
1066 	mfccp = &mfcctl2;
1067 	memset(&mfcctl2, 0, sizeof(mfcctl2));
1068 
1069 	if (mrt_api_config & MRT_API_FLAGS_ALL)
1070 		error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl2));
1071 	else
1072 		error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl));
1073 
1074 	if (error)
1075 		return (error);
1076 
1077 	s = splsoftnet();
1078 	rt = mfc_find(&mfccp->mfcc_origin, &mfccp->mfcc_mcastgrp);
1079 
1080 	/* If an entry already exists, just update the fields */
1081 	if (rt) {
1082 		if (mrtdebug & DEBUG_MFC)
1083 			log(LOG_DEBUG, "add_mfc update o %x g %x p %x\n",
1084 			    ntohl(mfccp->mfcc_origin.s_addr),
1085 			    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1086 			    mfccp->mfcc_parent);
1087 
1088 		update_mfc_params(rt, mfccp);
1089 
1090 		splx(s);
1091 		return (0);
1092 	}
1093 
1094 	/*
1095 	 * Find the entry for which the upcall was made and update
1096 	 */
1097 	nstl = 0;
1098 	hash = MFCHASH(mfccp->mfcc_origin, mfccp->mfcc_mcastgrp);
1099 	LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) {
1100 		if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) &&
1101 		    in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp) &&
1102 		    rt->mfc_stall != NULL) {
1103 			if (nstl++)
1104 				log(LOG_ERR, "add_mfc %s o %x g %x p %x dbx %p\n",
1105 				    "multiple kernel entries",
1106 				    ntohl(mfccp->mfcc_origin.s_addr),
1107 				    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1108 				    mfccp->mfcc_parent, rt->mfc_stall);
1109 
1110 			if (mrtdebug & DEBUG_MFC)
1111 				log(LOG_DEBUG, "add_mfc o %x g %x p %x dbg %p\n",
1112 				    ntohl(mfccp->mfcc_origin.s_addr),
1113 				    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1114 				    mfccp->mfcc_parent, rt->mfc_stall);
1115 
1116 			rte = rt->mfc_stall;
1117 			init_mfc_params(rt, mfccp);
1118 			rt->mfc_stall = NULL;
1119 
1120 			rt->mfc_expire = 0; /* Don't clean this guy up */
1121 			nexpire[hash]--;
1122 
1123 			/* free packets Qed at the end of this entry */
1124 			for (; rte != NULL; rte = nrte) {
1125 				nrte = rte->next;
1126 				if (rte->ifp) {
1127 #ifdef RSVP_ISI
1128 					ip_mdq(rte->m, rte->ifp, rt, -1);
1129 #else
1130 					ip_mdq(rte->m, rte->ifp, rt);
1131 #endif /* RSVP_ISI */
1132 				}
1133 				m_freem(rte->m);
1134 #ifdef UPCALL_TIMING
1135 				collate(&rte->t);
1136 #endif /* UPCALL_TIMING */
1137 				free(rte, M_MRTABLE);
1138 			}
1139 		}
1140 	}
1141 
1142 	/*
1143 	 * It is possible that an entry is being inserted without an upcall
1144 	 */
1145 	if (nstl == 0) {
1146 		/*
1147 		 * No mfc; make a new one
1148 		 */
1149 		if (mrtdebug & DEBUG_MFC)
1150 			log(LOG_DEBUG, "add_mfc no upcall o %x g %x p %x\n",
1151 			    ntohl(mfccp->mfcc_origin.s_addr),
1152 			    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1153 			    mfccp->mfcc_parent);
1154 
1155 		LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) {
1156 			if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) &&
1157 			    in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp)) {
1158 				init_mfc_params(rt, mfccp);
1159 				if (rt->mfc_expire)
1160 					nexpire[hash]--;
1161 				rt->mfc_expire = 0;
1162 				break; /* XXX */
1163 			}
1164 		}
1165 		if (rt == NULL) {	/* no upcall, so make a new entry */
1166 			rt = (struct mfc *)malloc(sizeof(*rt), M_MRTABLE,
1167 						  M_NOWAIT);
1168 			if (rt == NULL) {
1169 				splx(s);
1170 				return (ENOBUFS);
1171 			}
1172 
1173 			init_mfc_params(rt, mfccp);
1174 			rt->mfc_expire	= 0;
1175 			rt->mfc_stall	= NULL;
1176 			rt->mfc_bw_meter = NULL;
1177 
1178 			/* insert new entry at head of hash chain */
1179 			LIST_INSERT_HEAD(&mfchashtbl[hash], rt, mfc_hash);
1180 		}
1181 	}
1182 
1183 	splx(s);
1184 	return (0);
1185 }
1186 
1187 #ifdef UPCALL_TIMING
1188 /*
1189  * collect delay statistics on the upcalls
1190  */
1191 static void
1192 collate(struct timeval *t)
1193 {
1194 	u_int32_t d;
1195 	struct timeval tp;
1196 	u_int32_t delta;
1197 
1198 	microtime(&tp);
1199 
1200 	if (timercmp(t, &tp, <)) {
1201 		TV_DELTA(tp, *t, delta);
1202 
1203 		d = delta >> 10;
1204 		if (d > 50)
1205 			d = 50;
1206 
1207 		++upcall_data[d];
1208 	}
1209 }
1210 #endif /* UPCALL_TIMING */
1211 
1212 /*
1213  * Delete an mfc entry
1214  */
1215 static int
1216 del_mfc(struct sockopt *sopt)
1217 {
1218 	struct mfcctl2 mfcctl2;
1219 	struct mfcctl2 *mfccp;
1220 	struct mfc *rt;
1221 	int s;
1222 	int error;
1223 
1224 	/*
1225 	 * XXX: for deleting MFC entries the information in entries
1226 	 * of size "struct mfcctl" is sufficient.
1227 	 */
1228 
1229 	mfccp = &mfcctl2;
1230 	memset(&mfcctl2, 0, sizeof(mfcctl2));
1231 
1232 	error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl));
1233 	if (error) {
1234 		/* Try with the size of mfcctl2. */
1235 		error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl2));
1236 		if (error)
1237 			return (error);
1238 	}
1239 
1240 	if (mrtdebug & DEBUG_MFC)
1241 		log(LOG_DEBUG, "del_mfc origin %x mcastgrp %x\n",
1242 		    ntohl(mfccp->mfcc_origin.s_addr),
1243 		    ntohl(mfccp->mfcc_mcastgrp.s_addr));
1244 
1245 	s = splsoftnet();
1246 
1247 	rt = mfc_find(&mfccp->mfcc_origin, &mfccp->mfcc_mcastgrp);
1248 	if (rt == NULL) {
1249 		splx(s);
1250 		return (EADDRNOTAVAIL);
1251 	}
1252 
1253 	/*
1254 	 * free the bw_meter entries
1255 	 */
1256 	free_bw_list(rt->mfc_bw_meter);
1257 	rt->mfc_bw_meter = NULL;
1258 
1259 	LIST_REMOVE(rt, mfc_hash);
1260 	free(rt, M_MRTABLE);
1261 
1262 	splx(s);
1263 	return (0);
1264 }
1265 
1266 static int
1267 socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in *src)
1268 {
1269 	if (s) {
1270 		if (sbappendaddr(&s->so_rcv, sintosa(src), mm, NULL) != 0) {
1271 			sorwakeup(s);
1272 			return (0);
1273 		}
1274 	}
1275 	m_freem(mm);
1276 	return (-1);
1277 }
1278 
1279 /*
1280  * IP multicast forwarding function. This function assumes that the packet
1281  * pointed to by "ip" has arrived on (or is about to be sent to) the interface
1282  * pointed to by "ifp", and the packet is to be relayed to other networks
1283  * that have members of the packet's destination IP multicast group.
1284  *
1285  * The packet is returned unscathed to the caller, unless it is
1286  * erroneous, in which case a non-zero return value tells the caller to
1287  * discard it.
1288  */
1289 
1290 #define IP_HDR_LEN  20	/* # bytes of fixed IP header (excluding options) */
1291 #define TUNNEL_LEN  12  /* # bytes of IP option for tunnel encapsulation  */
1292 
1293 int
1294 #ifdef RSVP_ISI
1295 ip_mforward(struct mbuf *m, struct ifnet *ifp, struct ip_moptions *imo)
1296 #else
1297 ip_mforward(struct mbuf *m, struct ifnet *ifp)
1298 #endif /* RSVP_ISI */
1299 {
1300 	struct ip *ip = mtod(m, struct ip *);
1301 	struct mfc *rt;
1302 	static int srctun = 0;
1303 	struct mbuf *mm;
1304 	struct sockaddr_in sin;
1305 	int s;
1306 	vifi_t vifi;
1307 
1308 	if (mrtdebug & DEBUG_FORWARD)
1309 		log(LOG_DEBUG, "ip_mforward: src %x, dst %x, ifp %p\n",
1310 		    ntohl(ip->ip_src.s_addr), ntohl(ip->ip_dst.s_addr), ifp);
1311 
1312 	if (ip->ip_hl < (IP_HDR_LEN + TUNNEL_LEN) >> 2 ||
1313 	    ((u_char *)(ip + 1))[1] != IPOPT_LSRR) {
1314 		/*
1315 		 * Packet arrived via a physical interface or
1316 		 * an encapsulated tunnel or a register_vif.
1317 		 */
1318 	} else {
1319 		/*
1320 		 * Packet arrived through a source-route tunnel.
1321 		 * Source-route tunnels are no longer supported.
1322 		 */
1323 		if ((srctun++ % 1000) == 0)
1324 			log(LOG_ERR,
1325 			    "ip_mforward: received source-routed packet from %x\n",
1326 			    ntohl(ip->ip_src.s_addr));
1327 
1328 		return (1);
1329 	}
1330 
1331 	/*
1332 	 * Clear any in-bound checksum flags for this packet.
1333 	 */
1334 	m->m_pkthdr.csum_flags = 0;
1335 
1336 #ifdef RSVP_ISI
1337 	if (imo && ((vifi = imo->imo_multicast_vif) < numvifs)) {
1338 		if (ip->ip_ttl < MAXTTL)
1339 			ip->ip_ttl++;	/* compensate for -1 in *_send routines */
1340 		if (rsvpdebug && ip->ip_p == IPPROTO_RSVP) {
1341 			struct vif *vifp = viftable + vifi;
1342 			printf("Sending IPPROTO_RSVP from %x to %x on vif %d (%s%s)\n",
1343 			    ntohl(ip->ip_src), ntohl(ip->ip_dst), vifi,
1344 			    (vifp->v_flags & VIFF_TUNNEL) ? "tunnel on " : "",
1345 			    vifp->v_ifp->if_xname);
1346 		}
1347 		return (ip_mdq(m, ifp, NULL, vifi));
1348 	}
1349 	if (rsvpdebug && ip->ip_p == IPPROTO_RSVP) {
1350 		printf("Warning: IPPROTO_RSVP from %x to %x without vif option\n",
1351 		    ntohl(ip->ip_src), ntohl(ip->ip_dst));
1352 	}
1353 #endif /* RSVP_ISI */
1354 
1355 	/*
1356 	 * Don't forward a packet with time-to-live of zero or one,
1357 	 * or a packet destined to a local-only group.
1358 	 */
1359 	if (ip->ip_ttl <= 1 || IN_LOCAL_GROUP(ip->ip_dst.s_addr))
1360 		return (0);
1361 
1362 	/*
1363 	 * Determine forwarding vifs from the forwarding cache table
1364 	 */
1365 	s = splsoftnet();
1366 	++mrtstat.mrts_mfc_lookups;
1367 	rt = mfc_find(&ip->ip_src, &ip->ip_dst);
1368 
1369 	/* Entry exists, so forward if necessary */
1370 	if (rt != NULL) {
1371 		splx(s);
1372 #ifdef RSVP_ISI
1373 		return (ip_mdq(m, ifp, rt, -1));
1374 #else
1375 		return (ip_mdq(m, ifp, rt));
1376 #endif /* RSVP_ISI */
1377 	} else {
1378 		/*
1379 		 * If we don't have a route for packet's origin,
1380 		 * Make a copy of the packet & send message to routing daemon
1381 		 */
1382 
1383 		struct mbuf *mb0;
1384 		struct rtdetq *rte;
1385 		u_int32_t hash;
1386 		int hlen = ip->ip_hl << 2;
1387 #ifdef UPCALL_TIMING
1388 		struct timeval tp;
1389 
1390 		microtime(&tp);
1391 #endif /* UPCALL_TIMING */
1392 
1393 		++mrtstat.mrts_mfc_misses;
1394 
1395 		mrtstat.mrts_no_route++;
1396 		if (mrtdebug & (DEBUG_FORWARD | DEBUG_MFC))
1397 			log(LOG_DEBUG, "ip_mforward: no rte s %x g %x\n",
1398 			    ntohl(ip->ip_src.s_addr),
1399 			    ntohl(ip->ip_dst.s_addr));
1400 
1401 		/*
1402 		 * Allocate mbufs early so that we don't do extra work if we are
1403 		 * just going to fail anyway.  Make sure to pullup the header so
1404 		 * that other people can't step on it.
1405 		 */
1406 		rte = (struct rtdetq *)malloc(sizeof(*rte), M_MRTABLE,
1407 					      M_NOWAIT);
1408 		if (rte == NULL) {
1409 			splx(s);
1410 			return (ENOBUFS);
1411 		}
1412 		mb0 = m_copypacket(m, M_DONTWAIT);
1413 		M_PULLUP(mb0, hlen);
1414 		if (mb0 == NULL) {
1415 			free(rte, M_MRTABLE);
1416 			splx(s);
1417 			return (ENOBUFS);
1418 		}
1419 
1420 		/* is there an upcall waiting for this flow? */
1421 		hash = MFCHASH(ip->ip_src, ip->ip_dst);
1422 		LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) {
1423 			if (in_hosteq(ip->ip_src, rt->mfc_origin) &&
1424 			    in_hosteq(ip->ip_dst, rt->mfc_mcastgrp) &&
1425 			    rt->mfc_stall != NULL)
1426 				break;
1427 		}
1428 
1429 		if (rt == NULL) {
1430 			int i;
1431 			struct igmpmsg *im;
1432 
1433 			/*
1434 			 * Locate the vifi for the incoming interface for
1435 			 * this packet.
1436 			 * If none found, drop packet.
1437 			 */
1438 			for (vifi = 0; vifi < numvifs &&
1439 				 viftable[vifi].v_ifp != ifp; vifi++)
1440 				;
1441 			if (vifi >= numvifs) /* vif not found, drop packet */
1442 				goto non_fatal;
1443 
1444 			/* no upcall, so make a new entry */
1445 			rt = (struct mfc *)malloc(sizeof(*rt), M_MRTABLE,
1446 						  M_NOWAIT);
1447 			if (rt == NULL)
1448 				goto fail;
1449 
1450 			/*
1451 			 * Make a copy of the header to send to the user level
1452 			 * process
1453 			 */
1454 			mm = m_copym(m, 0, hlen, M_DONTWAIT);
1455 			M_PULLUP(mm, hlen);
1456 			if (mm == NULL)
1457 				goto fail1;
1458 
1459 			/*
1460 			 * Send message to routing daemon to install
1461 			 * a route into the kernel table
1462 			 */
1463 
1464 			im = mtod(mm, struct igmpmsg *);
1465 			im->im_msgtype = IGMPMSG_NOCACHE;
1466 			im->im_mbz = 0;
1467 			im->im_vif = vifi;
1468 
1469 			mrtstat.mrts_upcalls++;
1470 
1471 			sockaddr_in_init(&sin, &ip->ip_src, 0);
1472 			if (socket_send(ip_mrouter, mm, &sin) < 0) {
1473 				log(LOG_WARNING,
1474 				    "ip_mforward: ip_mrouter socket queue full\n");
1475 				++mrtstat.mrts_upq_sockfull;
1476 			fail1:
1477 				free(rt, M_MRTABLE);
1478 			fail:
1479 				free(rte, M_MRTABLE);
1480 				m_freem(mb0);
1481 				splx(s);
1482 				return (ENOBUFS);
1483 			}
1484 
1485 			/* insert new entry at head of hash chain */
1486 			rt->mfc_origin = ip->ip_src;
1487 			rt->mfc_mcastgrp = ip->ip_dst;
1488 			rt->mfc_pkt_cnt = 0;
1489 			rt->mfc_byte_cnt = 0;
1490 			rt->mfc_wrong_if = 0;
1491 			rt->mfc_expire = UPCALL_EXPIRE;
1492 			nexpire[hash]++;
1493 			for (i = 0; i < numvifs; i++) {
1494 				rt->mfc_ttls[i] = 0;
1495 				rt->mfc_flags[i] = 0;
1496 			}
1497 			rt->mfc_parent = -1;
1498 
1499 			/* clear the RP address */
1500 			rt->mfc_rp = zeroin_addr;
1501 
1502 			rt->mfc_bw_meter = NULL;
1503 
1504 			/* link into table */
1505 			LIST_INSERT_HEAD(&mfchashtbl[hash], rt, mfc_hash);
1506 			/* Add this entry to the end of the queue */
1507 			rt->mfc_stall = rte;
1508 		} else {
1509 			/* determine if q has overflowed */
1510 			struct rtdetq **p;
1511 			int npkts = 0;
1512 
1513 			/*
1514 			 * XXX ouch! we need to append to the list, but we
1515 			 * only have a pointer to the front, so we have to
1516 			 * scan the entire list every time.
1517 			 */
1518 			for (p = &rt->mfc_stall; *p != NULL; p = &(*p)->next)
1519 				if (++npkts > MAX_UPQ) {
1520 					mrtstat.mrts_upq_ovflw++;
1521 				non_fatal:
1522 					free(rte, M_MRTABLE);
1523 					m_freem(mb0);
1524 					splx(s);
1525 					return (0);
1526 				}
1527 
1528 			/* Add this entry to the end of the queue */
1529 			*p = rte;
1530 		}
1531 
1532 		rte->next = NULL;
1533 		rte->m = mb0;
1534 		rte->ifp = ifp;
1535 #ifdef UPCALL_TIMING
1536 		rte->t = tp;
1537 #endif /* UPCALL_TIMING */
1538 
1539 		splx(s);
1540 
1541 		return (0);
1542 	}
1543 }
1544 
1545 
1546 /*ARGSUSED*/
1547 static void
1548 expire_upcalls(void *v)
1549 {
1550 	int i;
1551 	int s;
1552 
1553 	s = splsoftnet();
1554 
1555 	for (i = 0; i < MFCTBLSIZ; i++) {
1556 		struct mfc *rt, *nrt;
1557 
1558 		if (nexpire[i] == 0)
1559 			continue;
1560 
1561 		for (rt = LIST_FIRST(&mfchashtbl[i]); rt; rt = nrt) {
1562 			nrt = LIST_NEXT(rt, mfc_hash);
1563 
1564 			if (rt->mfc_expire == 0 || --rt->mfc_expire > 0)
1565 				continue;
1566 			nexpire[i]--;
1567 
1568 			/*
1569 			 * free the bw_meter entries
1570 			 */
1571 			while (rt->mfc_bw_meter != NULL) {
1572 				struct bw_meter *x = rt->mfc_bw_meter;
1573 
1574 				rt->mfc_bw_meter = x->bm_mfc_next;
1575 				kmem_free(x, sizeof(*x));
1576 			}
1577 
1578 			++mrtstat.mrts_cache_cleanups;
1579 			if (mrtdebug & DEBUG_EXPIRE)
1580 				log(LOG_DEBUG,
1581 				    "expire_upcalls: expiring (%x %x)\n",
1582 				    ntohl(rt->mfc_origin.s_addr),
1583 				    ntohl(rt->mfc_mcastgrp.s_addr));
1584 
1585 			expire_mfc(rt);
1586 		}
1587 	}
1588 
1589 	splx(s);
1590 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
1591 	    expire_upcalls, NULL);
1592 }
1593 
1594 /*
1595  * Packet forwarding routine once entry in the cache is made
1596  */
1597 static int
1598 #ifdef RSVP_ISI
1599 ip_mdq(struct mbuf *m, struct ifnet *ifp, struct mfc *rt, vifi_t xmt_vif)
1600 #else
1601 ip_mdq(struct mbuf *m, struct ifnet *ifp, struct mfc *rt)
1602 #endif /* RSVP_ISI */
1603 {
1604 	struct ip  *ip = mtod(m, struct ip *);
1605 	vifi_t vifi;
1606 	struct vif *vifp;
1607 	struct sockaddr_in sin;
1608 	int plen = ntohs(ip->ip_len) - (ip->ip_hl << 2);
1609 
1610 /*
1611  * Macro to send packet on vif.  Since RSVP packets don't get counted on
1612  * input, they shouldn't get counted on output, so statistics keeping is
1613  * separate.
1614  */
1615 #define MC_SEND(ip, vifp, m) do {					\
1616 	if ((vifp)->v_flags & VIFF_TUNNEL)				\
1617 		encap_send((ip), (vifp), (m));				\
1618 	else								\
1619 		phyint_send((ip), (vifp), (m));				\
1620 } while (/*CONSTCOND*/ 0)
1621 
1622 #ifdef RSVP_ISI
1623 	/*
1624 	 * If xmt_vif is not -1, send on only the requested vif.
1625 	 *
1626 	 * (since vifi_t is u_short, -1 becomes MAXUSHORT, which > numvifs.
1627 	 */
1628 	if (xmt_vif < numvifs) {
1629 #ifdef PIM
1630 		if (viftable[xmt_vif].v_flags & VIFF_REGISTER)
1631 			pim_register_send(ip, viftable + xmt_vif, m, rt);
1632 		else
1633 #endif
1634 		MC_SEND(ip, viftable + xmt_vif, m);
1635 		return (1);
1636 	}
1637 #endif /* RSVP_ISI */
1638 
1639 	/*
1640 	 * Don't forward if it didn't arrive from the parent vif for its origin.
1641 	 */
1642 	vifi = rt->mfc_parent;
1643 	if ((vifi >= numvifs) || (viftable[vifi].v_ifp != ifp)) {
1644 		/* came in the wrong interface */
1645 		if (mrtdebug & DEBUG_FORWARD)
1646 			log(LOG_DEBUG, "wrong if: ifp %p vifi %d vififp %p\n",
1647 			    ifp, vifi,
1648 			    vifi >= numvifs ? 0 : viftable[vifi].v_ifp);
1649 		++mrtstat.mrts_wrong_if;
1650 		++rt->mfc_wrong_if;
1651 		/*
1652 		 * If we are doing PIM assert processing, send a message
1653 		 * to the routing daemon.
1654 		 *
1655 		 * XXX: A PIM-SM router needs the WRONGVIF detection so it
1656 		 * can complete the SPT switch, regardless of the type
1657 		 * of the iif (broadcast media, GRE tunnel, etc).
1658 		 */
1659 		if (pim_assert && (vifi < numvifs) && viftable[vifi].v_ifp) {
1660 			struct timeval now;
1661 			u_int32_t delta;
1662 
1663 #ifdef PIM
1664 			if (ifp == &multicast_register_if)
1665 				pimstat.pims_rcv_registers_wrongiif++;
1666 #endif
1667 
1668 			/* Get vifi for the incoming packet */
1669 			for (vifi = 0;
1670 			     vifi < numvifs && viftable[vifi].v_ifp != ifp;
1671 			     vifi++)
1672 			    ;
1673 			if (vifi >= numvifs) {
1674 				/* The iif is not found: ignore the packet. */
1675 				return (0);
1676 			}
1677 
1678 			if (rt->mfc_flags[vifi] &
1679 			    MRT_MFC_FLAGS_DISABLE_WRONGVIF) {
1680 				/* WRONGVIF disabled: ignore the packet */
1681 				return (0);
1682 			}
1683 
1684 			microtime(&now);
1685 
1686 			TV_DELTA(rt->mfc_last_assert, now, delta);
1687 
1688 			if (delta > ASSERT_MSG_TIME) {
1689 				struct igmpmsg *im;
1690 				int hlen = ip->ip_hl << 2;
1691 				struct mbuf *mm =
1692 				    m_copym(m, 0, hlen, M_DONTWAIT);
1693 
1694 				M_PULLUP(mm, hlen);
1695 				if (mm == NULL)
1696 					return (ENOBUFS);
1697 
1698 				rt->mfc_last_assert = now;
1699 
1700 				im = mtod(mm, struct igmpmsg *);
1701 				im->im_msgtype	= IGMPMSG_WRONGVIF;
1702 				im->im_mbz	= 0;
1703 				im->im_vif	= vifi;
1704 
1705 				mrtstat.mrts_upcalls++;
1706 
1707 				sockaddr_in_init(&sin, &im->im_src, 0);
1708 				if (socket_send(ip_mrouter, mm, &sin) < 0) {
1709 					log(LOG_WARNING,
1710 					    "ip_mforward: ip_mrouter socket queue full\n");
1711 					++mrtstat.mrts_upq_sockfull;
1712 					return (ENOBUFS);
1713 				}
1714 			}
1715 		}
1716 		return (0);
1717 	}
1718 
1719 	/* If I sourced this packet, it counts as output, else it was input. */
1720 	if (in_hosteq(ip->ip_src, viftable[vifi].v_lcl_addr)) {
1721 		viftable[vifi].v_pkt_out++;
1722 		viftable[vifi].v_bytes_out += plen;
1723 	} else {
1724 		viftable[vifi].v_pkt_in++;
1725 		viftable[vifi].v_bytes_in += plen;
1726 	}
1727 	rt->mfc_pkt_cnt++;
1728 	rt->mfc_byte_cnt += plen;
1729 
1730 	/*
1731 	 * For each vif, decide if a copy of the packet should be forwarded.
1732 	 * Forward if:
1733 	 *		- the ttl exceeds the vif's threshold
1734 	 *		- there are group members downstream on interface
1735 	 */
1736 	for (vifp = viftable, vifi = 0; vifi < numvifs; vifp++, vifi++)
1737 		if ((rt->mfc_ttls[vifi] > 0) &&
1738 			(ip->ip_ttl > rt->mfc_ttls[vifi])) {
1739 			vifp->v_pkt_out++;
1740 			vifp->v_bytes_out += plen;
1741 #ifdef PIM
1742 			if (vifp->v_flags & VIFF_REGISTER)
1743 				pim_register_send(ip, vifp, m, rt);
1744 			else
1745 #endif
1746 			MC_SEND(ip, vifp, m);
1747 		}
1748 
1749 	/*
1750 	 * Perform upcall-related bw measuring.
1751 	 */
1752 	if (rt->mfc_bw_meter != NULL) {
1753 		struct bw_meter *x;
1754 		struct timeval now;
1755 
1756 		microtime(&now);
1757 		for (x = rt->mfc_bw_meter; x != NULL; x = x->bm_mfc_next)
1758 			bw_meter_receive_packet(x, plen, &now);
1759 	}
1760 
1761 	return (0);
1762 }
1763 
1764 #ifdef RSVP_ISI
1765 /*
1766  * check if a vif number is legal/ok. This is used by ip_output.
1767  */
1768 int
1769 legal_vif_num(int vif)
1770 {
1771 	if (vif >= 0 && vif < numvifs)
1772 		return (1);
1773 	else
1774 		return (0);
1775 }
1776 #endif /* RSVP_ISI */
1777 
1778 static void
1779 phyint_send(struct ip *ip, struct vif *vifp, struct mbuf *m)
1780 {
1781 	struct mbuf *mb_copy;
1782 	int hlen = ip->ip_hl << 2;
1783 
1784 	/*
1785 	 * Make a new reference to the packet; make sure that
1786 	 * the IP header is actually copied, not just referenced,
1787 	 * so that ip_output() only scribbles on the copy.
1788 	 */
1789 	mb_copy = m_copypacket(m, M_DONTWAIT);
1790 	M_PULLUP(mb_copy, hlen);
1791 	if (mb_copy == NULL)
1792 		return;
1793 
1794 	if (vifp->v_rate_limit <= 0)
1795 		tbf_send_packet(vifp, mb_copy);
1796 	else
1797 		tbf_control(vifp, mb_copy, mtod(mb_copy, struct ip *),
1798 		    ntohs(ip->ip_len));
1799 }
1800 
1801 static void
1802 encap_send(struct ip *ip, struct vif *vifp, struct mbuf *m)
1803 {
1804 	struct mbuf *mb_copy;
1805 	struct ip *ip_copy;
1806 	int i, len = ntohs(ip->ip_len) + sizeof(multicast_encap_iphdr);
1807 
1808 	/* Take care of delayed checksums */
1809 	if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
1810 		in_delayed_cksum(m);
1811 		m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4);
1812 	}
1813 
1814 	/*
1815 	 * copy the old packet & pullup it's IP header into the
1816 	 * new mbuf so we can modify it.  Try to fill the new
1817 	 * mbuf since if we don't the ethernet driver will.
1818 	 */
1819 	MGETHDR(mb_copy, M_DONTWAIT, MT_DATA);
1820 	if (mb_copy == NULL)
1821 		return;
1822 	mb_copy->m_data += max_linkhdr;
1823 	mb_copy->m_pkthdr.len = len;
1824 	mb_copy->m_len = sizeof(multicast_encap_iphdr);
1825 
1826 	if ((mb_copy->m_next = m_copypacket(m, M_DONTWAIT)) == NULL) {
1827 		m_freem(mb_copy);
1828 		return;
1829 	}
1830 	i = MHLEN - max_linkhdr;
1831 	if (i > len)
1832 		i = len;
1833 	mb_copy = m_pullup(mb_copy, i);
1834 	if (mb_copy == NULL)
1835 		return;
1836 
1837 	/*
1838 	 * fill in the encapsulating IP header.
1839 	 */
1840 	ip_copy = mtod(mb_copy, struct ip *);
1841 	*ip_copy = multicast_encap_iphdr;
1842 	if (len < IP_MINFRAGSIZE)
1843 		ip_copy->ip_id = 0;
1844 	else
1845 		ip_copy->ip_id = ip_newid(NULL);
1846 	ip_copy->ip_len = htons(len);
1847 	ip_copy->ip_src = vifp->v_lcl_addr;
1848 	ip_copy->ip_dst = vifp->v_rmt_addr;
1849 
1850 	/*
1851 	 * turn the encapsulated IP header back into a valid one.
1852 	 */
1853 	ip = (struct ip *)((char *)ip_copy + sizeof(multicast_encap_iphdr));
1854 	--ip->ip_ttl;
1855 	ip->ip_sum = 0;
1856 	mb_copy->m_data += sizeof(multicast_encap_iphdr);
1857 	ip->ip_sum = in_cksum(mb_copy, ip->ip_hl << 2);
1858 	mb_copy->m_data -= sizeof(multicast_encap_iphdr);
1859 
1860 	if (vifp->v_rate_limit <= 0)
1861 		tbf_send_packet(vifp, mb_copy);
1862 	else
1863 		tbf_control(vifp, mb_copy, ip, ntohs(ip_copy->ip_len));
1864 }
1865 
1866 /*
1867  * De-encapsulate a packet and feed it back through ip input.
1868  */
1869 static void
1870 vif_input(struct mbuf *m, ...)
1871 {
1872 	int off, proto;
1873 	va_list ap;
1874 	struct vif *vifp;
1875 
1876 	va_start(ap, m);
1877 	off = va_arg(ap, int);
1878 	proto = va_arg(ap, int);
1879 	va_end(ap);
1880 
1881 	vifp = (struct vif *)encap_getarg(m);
1882 	if (!vifp || proto != ENCAP_PROTO) {
1883 		m_freem(m);
1884 		mrtstat.mrts_bad_tunnel++;
1885 		return;
1886 	}
1887 
1888 	m_adj(m, off);
1889 	m->m_pkthdr.rcvif = vifp->v_ifp;
1890 
1891 	if (__predict_false(!pktq_enqueue(ip_pktq, m, 0))) {
1892 		m_freem(m);
1893 	}
1894 }
1895 
1896 /*
1897  * Check if the packet should be received on the vif denoted by arg.
1898  * (The encap selection code will call this once per vif since each is
1899  * registered separately.)
1900  */
1901 static int
1902 vif_encapcheck(struct mbuf *m, int off, int proto, void *arg)
1903 {
1904 	struct vif *vifp;
1905 	struct ip ip;
1906 
1907 #ifdef DIAGNOSTIC
1908 	if (!arg || proto != IPPROTO_IPV4)
1909 		panic("unexpected arg in vif_encapcheck");
1910 #endif
1911 
1912 	/*
1913 	 * Accept the packet only if the inner heaader is multicast
1914 	 * and the outer header matches a tunnel-mode vif.  Order
1915 	 * checks in the hope that common non-matching packets will be
1916 	 * rejected quickly.  Assume that unicast IPv4 traffic in a
1917 	 * parallel tunnel (e.g. gif(4)) is unlikely.
1918 	 */
1919 
1920 	/* Obtain the outer IP header and the vif pointer. */
1921 	m_copydata((struct mbuf *)m, 0, sizeof(ip), (void *)&ip);
1922 	vifp = (struct vif *)arg;
1923 
1924 	/*
1925 	 * The outer source must match the vif's remote peer address.
1926 	 * For a multicast router with several tunnels, this is the
1927 	 * only check that will fail on packets in other tunnels,
1928 	 * assuming the local address is the same.
1929 	 */
1930 	if (!in_hosteq(vifp->v_rmt_addr, ip.ip_src))
1931 		return 0;
1932 
1933 	/* The outer destination must match the vif's local address. */
1934 	if (!in_hosteq(vifp->v_lcl_addr, ip.ip_dst))
1935 		return 0;
1936 
1937 	/* The vif must be of tunnel type. */
1938 	if ((vifp->v_flags & VIFF_TUNNEL) == 0)
1939 		return 0;
1940 
1941 	/* Check that the inner destination is multicast. */
1942 	m_copydata((struct mbuf *)m, off, sizeof(ip), (void *)&ip);
1943 	if (!IN_MULTICAST(ip.ip_dst.s_addr))
1944 		return 0;
1945 
1946 	/*
1947 	 * We have checked that both the outer src and dst addresses
1948 	 * match the vif, and that the inner destination is multicast
1949 	 * (224/5).  By claiming more than 64, we intend to
1950 	 * preferentially take packets that also match a parallel
1951 	 * gif(4).
1952 	 */
1953 	return 32 + 32 + 5;
1954 }
1955 
1956 /*
1957  * Token bucket filter module
1958  */
1959 static void
1960 tbf_control(struct vif *vifp, struct mbuf *m, struct ip *ip, u_int32_t len)
1961 {
1962 
1963 	if (len > MAX_BKT_SIZE) {
1964 		/* drop if packet is too large */
1965 		mrtstat.mrts_pkt2large++;
1966 		m_freem(m);
1967 		return;
1968 	}
1969 
1970 	tbf_update_tokens(vifp);
1971 
1972 	/*
1973 	 * If there are enough tokens, and the queue is empty, send this packet
1974 	 * out immediately.  Otherwise, try to insert it on this vif's queue.
1975 	 */
1976 	if (vifp->tbf_q_len == 0) {
1977 		if (len <= vifp->tbf_n_tok) {
1978 			vifp->tbf_n_tok -= len;
1979 			tbf_send_packet(vifp, m);
1980 		} else {
1981 			/* queue packet and timeout till later */
1982 			tbf_queue(vifp, m);
1983 			callout_reset(&vifp->v_repq_ch, TBF_REPROCESS,
1984 			    tbf_reprocess_q, vifp);
1985 		}
1986 	} else {
1987 		if (vifp->tbf_q_len >= vifp->tbf_max_q_len &&
1988 		    !tbf_dq_sel(vifp, ip)) {
1989 			/* queue full, and couldn't make room */
1990 			mrtstat.mrts_q_overflow++;
1991 			m_freem(m);
1992 		} else {
1993 			/* queue length low enough, or made room */
1994 			tbf_queue(vifp, m);
1995 			tbf_process_q(vifp);
1996 		}
1997 	}
1998 }
1999 
2000 /*
2001  * adds a packet to the queue at the interface
2002  */
2003 static void
2004 tbf_queue(struct vif *vifp, struct mbuf *m)
2005 {
2006 	int s = splsoftnet();
2007 
2008 	/* insert at tail */
2009 	*vifp->tbf_t = m;
2010 	vifp->tbf_t = &m->m_nextpkt;
2011 	vifp->tbf_q_len++;
2012 
2013 	splx(s);
2014 }
2015 
2016 
2017 /*
2018  * processes the queue at the interface
2019  */
2020 static void
2021 tbf_process_q(struct vif *vifp)
2022 {
2023 	struct mbuf *m;
2024 	int len;
2025 	int s = splsoftnet();
2026 
2027 	/*
2028 	 * Loop through the queue at the interface and send as many packets
2029 	 * as possible.
2030 	 */
2031 	for (m = vifp->tbf_q; m != NULL; m = vifp->tbf_q) {
2032 		len = ntohs(mtod(m, struct ip *)->ip_len);
2033 
2034 		/* determine if the packet can be sent */
2035 		if (len <= vifp->tbf_n_tok) {
2036 			/* if so,
2037 			 * reduce no of tokens, dequeue the packet,
2038 			 * send the packet.
2039 			 */
2040 			if ((vifp->tbf_q = m->m_nextpkt) == NULL)
2041 				vifp->tbf_t = &vifp->tbf_q;
2042 			--vifp->tbf_q_len;
2043 
2044 			m->m_nextpkt = NULL;
2045 			vifp->tbf_n_tok -= len;
2046 			tbf_send_packet(vifp, m);
2047 		} else
2048 			break;
2049 	}
2050 	splx(s);
2051 }
2052 
2053 static void
2054 tbf_reprocess_q(void *arg)
2055 {
2056 	struct vif *vifp = arg;
2057 
2058 	if (ip_mrouter == NULL)
2059 		return;
2060 
2061 	tbf_update_tokens(vifp);
2062 	tbf_process_q(vifp);
2063 
2064 	if (vifp->tbf_q_len != 0)
2065 		callout_reset(&vifp->v_repq_ch, TBF_REPROCESS,
2066 		    tbf_reprocess_q, vifp);
2067 }
2068 
2069 /* function that will selectively discard a member of the queue
2070  * based on the precedence value and the priority
2071  */
2072 static int
2073 tbf_dq_sel(struct vif *vifp, struct ip *ip)
2074 {
2075 	u_int p;
2076 	struct mbuf **mp, *m;
2077 	int s = splsoftnet();
2078 
2079 	p = priority(vifp, ip);
2080 
2081 	for (mp = &vifp->tbf_q, m = *mp;
2082 	    m != NULL;
2083 	    mp = &m->m_nextpkt, m = *mp) {
2084 		if (p > priority(vifp, mtod(m, struct ip *))) {
2085 			if ((*mp = m->m_nextpkt) == NULL)
2086 				vifp->tbf_t = mp;
2087 			--vifp->tbf_q_len;
2088 
2089 			m_freem(m);
2090 			mrtstat.mrts_drop_sel++;
2091 			splx(s);
2092 			return (1);
2093 		}
2094 	}
2095 	splx(s);
2096 	return (0);
2097 }
2098 
2099 static void
2100 tbf_send_packet(struct vif *vifp, struct mbuf *m)
2101 {
2102 	int error;
2103 	int s = splsoftnet();
2104 
2105 	if (vifp->v_flags & VIFF_TUNNEL) {
2106 		/* If tunnel options */
2107 		ip_output(m, NULL, &vifp->v_route, IP_FORWARDING, NULL, NULL);
2108 	} else {
2109 		/* if physical interface option, extract the options and then send */
2110 		struct ip_moptions imo;
2111 
2112 		imo.imo_multicast_ifp = vifp->v_ifp;
2113 		imo.imo_multicast_ttl = mtod(m, struct ip *)->ip_ttl - 1;
2114 		imo.imo_multicast_loop = 1;
2115 #ifdef RSVP_ISI
2116 		imo.imo_multicast_vif = -1;
2117 #endif
2118 
2119 		error = ip_output(m, NULL, NULL, IP_FORWARDING|IP_MULTICASTOPTS,
2120 		    &imo, NULL);
2121 
2122 		if (mrtdebug & DEBUG_XMIT)
2123 			log(LOG_DEBUG, "phyint_send on vif %ld err %d\n",
2124 			    (long)(vifp - viftable), error);
2125 	}
2126 	splx(s);
2127 }
2128 
2129 /* determine the current time and then
2130  * the elapsed time (between the last time and time now)
2131  * in milliseconds & update the no. of tokens in the bucket
2132  */
2133 static void
2134 tbf_update_tokens(struct vif *vifp)
2135 {
2136 	struct timeval tp;
2137 	u_int32_t tm;
2138 	int s = splsoftnet();
2139 
2140 	microtime(&tp);
2141 
2142 	TV_DELTA(tp, vifp->tbf_last_pkt_t, tm);
2143 
2144 	/*
2145 	 * This formula is actually
2146 	 * "time in seconds" * "bytes/second".
2147 	 *
2148 	 * (tm / 1000000) * (v_rate_limit * 1000 * (1000/1024) / 8)
2149 	 *
2150 	 * The (1000/1024) was introduced in add_vif to optimize
2151 	 * this divide into a shift.
2152 	 */
2153 	vifp->tbf_n_tok += tm * vifp->v_rate_limit / 8192;
2154 	vifp->tbf_last_pkt_t = tp;
2155 
2156 	if (vifp->tbf_n_tok > MAX_BKT_SIZE)
2157 		vifp->tbf_n_tok = MAX_BKT_SIZE;
2158 
2159 	splx(s);
2160 }
2161 
2162 static int
2163 priority(struct vif *vifp, struct ip *ip)
2164 {
2165 	int prio = 50;	/* the lowest priority -- default case */
2166 
2167 	/* temporary hack; may add general packet classifier some day */
2168 
2169 	/*
2170 	 * The UDP port space is divided up into four priority ranges:
2171 	 * [0, 16384)     : unclassified - lowest priority
2172 	 * [16384, 32768) : audio - highest priority
2173 	 * [32768, 49152) : whiteboard - medium priority
2174 	 * [49152, 65536) : video - low priority
2175 	 */
2176 	if (ip->ip_p == IPPROTO_UDP) {
2177 		struct udphdr *udp = (struct udphdr *)(((char *)ip) + (ip->ip_hl << 2));
2178 
2179 		switch (ntohs(udp->uh_dport) & 0xc000) {
2180 		case 0x4000:
2181 			prio = 70;
2182 			break;
2183 		case 0x8000:
2184 			prio = 60;
2185 			break;
2186 		case 0xc000:
2187 			prio = 55;
2188 			break;
2189 		}
2190 
2191 		if (tbfdebug > 1)
2192 			log(LOG_DEBUG, "port %x prio %d\n",
2193 			    ntohs(udp->uh_dport), prio);
2194 	}
2195 
2196 	return (prio);
2197 }
2198 
2199 /*
2200  * End of token bucket filter modifications
2201  */
2202 #ifdef RSVP_ISI
2203 int
2204 ip_rsvp_vif_init(struct socket *so, struct mbuf *m)
2205 {
2206 	int vifi, s;
2207 
2208 	if (rsvpdebug)
2209 		printf("ip_rsvp_vif_init: so_type = %d, pr_protocol = %d\n",
2210 		    so->so_type, so->so_proto->pr_protocol);
2211 
2212 	if (so->so_type != SOCK_RAW ||
2213 	    so->so_proto->pr_protocol != IPPROTO_RSVP)
2214 		return (EOPNOTSUPP);
2215 
2216 	/* Check mbuf. */
2217 	if (m == NULL || m->m_len != sizeof(int)) {
2218 		return (EINVAL);
2219 	}
2220 	vifi = *(mtod(m, int *));
2221 
2222 	if (rsvpdebug)
2223 		printf("ip_rsvp_vif_init: vif = %d rsvp_on = %d\n",
2224 		       vifi, rsvp_on);
2225 
2226 	s = splsoftnet();
2227 
2228 	/* Check vif. */
2229 	if (!legal_vif_num(vifi)) {
2230 		splx(s);
2231 		return (EADDRNOTAVAIL);
2232 	}
2233 
2234 	/* Check if socket is available. */
2235 	if (viftable[vifi].v_rsvpd != NULL) {
2236 		splx(s);
2237 		return (EADDRINUSE);
2238 	}
2239 
2240 	viftable[vifi].v_rsvpd = so;
2241 	/*
2242 	 * This may seem silly, but we need to be sure we don't over-increment
2243 	 * the RSVP counter, in case something slips up.
2244 	 */
2245 	if (!viftable[vifi].v_rsvp_on) {
2246 		viftable[vifi].v_rsvp_on = 1;
2247 		rsvp_on++;
2248 	}
2249 
2250 	splx(s);
2251 	return (0);
2252 }
2253 
2254 int
2255 ip_rsvp_vif_done(struct socket *so, struct mbuf *m)
2256 {
2257 	int vifi, s;
2258 
2259 	if (rsvpdebug)
2260 		printf("ip_rsvp_vif_done: so_type = %d, pr_protocol = %d\n",
2261 		    so->so_type, so->so_proto->pr_protocol);
2262 
2263 	if (so->so_type != SOCK_RAW ||
2264 	    so->so_proto->pr_protocol != IPPROTO_RSVP)
2265 		return (EOPNOTSUPP);
2266 
2267 	/* Check mbuf. */
2268 	if (m == NULL || m->m_len != sizeof(int)) {
2269 		return (EINVAL);
2270 	}
2271 	vifi = *(mtod(m, int *));
2272 
2273 	s = splsoftnet();
2274 
2275 	/* Check vif. */
2276 	if (!legal_vif_num(vifi)) {
2277 		splx(s);
2278 		return (EADDRNOTAVAIL);
2279 	}
2280 
2281 	if (rsvpdebug)
2282 		printf("ip_rsvp_vif_done: v_rsvpd = %x so = %x\n",
2283 		    viftable[vifi].v_rsvpd, so);
2284 
2285 	viftable[vifi].v_rsvpd = NULL;
2286 	/*
2287 	 * This may seem silly, but we need to be sure we don't over-decrement
2288 	 * the RSVP counter, in case something slips up.
2289 	 */
2290 	if (viftable[vifi].v_rsvp_on) {
2291 		viftable[vifi].v_rsvp_on = 0;
2292 		rsvp_on--;
2293 	}
2294 
2295 	splx(s);
2296 	return (0);
2297 }
2298 
2299 void
2300 ip_rsvp_force_done(struct socket *so)
2301 {
2302 	int vifi, s;
2303 
2304 	/* Don't bother if it is not the right type of socket. */
2305 	if (so->so_type != SOCK_RAW ||
2306 	    so->so_proto->pr_protocol != IPPROTO_RSVP)
2307 		return;
2308 
2309 	s = splsoftnet();
2310 
2311 	/*
2312 	 * The socket may be attached to more than one vif...this
2313 	 * is perfectly legal.
2314 	 */
2315 	for (vifi = 0; vifi < numvifs; vifi++) {
2316 		if (viftable[vifi].v_rsvpd == so) {
2317 			viftable[vifi].v_rsvpd = NULL;
2318 			/*
2319 			 * This may seem silly, but we need to be sure we don't
2320 			 * over-decrement the RSVP counter, in case something
2321 			 * slips up.
2322 			 */
2323 			if (viftable[vifi].v_rsvp_on) {
2324 				viftable[vifi].v_rsvp_on = 0;
2325 				rsvp_on--;
2326 			}
2327 		}
2328 	}
2329 
2330 	splx(s);
2331 	return;
2332 }
2333 
2334 void
2335 rsvp_input(struct mbuf *m, struct ifnet *ifp)
2336 {
2337 	int vifi, s;
2338 	struct ip *ip = mtod(m, struct ip *);
2339 	struct sockaddr_in rsvp_src;
2340 
2341 	if (rsvpdebug)
2342 		printf("rsvp_input: rsvp_on %d\n", rsvp_on);
2343 
2344 	/*
2345 	 * Can still get packets with rsvp_on = 0 if there is a local member
2346 	 * of the group to which the RSVP packet is addressed.  But in this
2347 	 * case we want to throw the packet away.
2348 	 */
2349 	if (!rsvp_on) {
2350 		m_freem(m);
2351 		return;
2352 	}
2353 
2354 	/*
2355 	 * If the old-style non-vif-associated socket is set, then use
2356 	 * it and ignore the new ones.
2357 	 */
2358 	if (ip_rsvpd != NULL) {
2359 		if (rsvpdebug)
2360 			printf("rsvp_input: "
2361 			    "Sending packet up old-style socket\n");
2362 		rip_input(m);	/*XXX*/
2363 		return;
2364 	}
2365 
2366 	s = splsoftnet();
2367 
2368 	if (rsvpdebug)
2369 		printf("rsvp_input: check vifs\n");
2370 
2371 	/* Find which vif the packet arrived on. */
2372 	for (vifi = 0; vifi < numvifs; vifi++) {
2373 		if (viftable[vifi].v_ifp == ifp)
2374 			break;
2375 	}
2376 
2377 	if (vifi == numvifs) {
2378 		/* Can't find vif packet arrived on. Drop packet. */
2379 		if (rsvpdebug)
2380 			printf("rsvp_input: "
2381 			    "Can't find vif for packet...dropping it.\n");
2382 		m_freem(m);
2383 		splx(s);
2384 		return;
2385 	}
2386 
2387 	if (rsvpdebug)
2388 		printf("rsvp_input: check socket\n");
2389 
2390 	if (viftable[vifi].v_rsvpd == NULL) {
2391 		/*
2392 		 * drop packet, since there is no specific socket for this
2393 		 * interface
2394 		 */
2395 		if (rsvpdebug)
2396 			printf("rsvp_input: No socket defined for vif %d\n",
2397 			    vifi);
2398 		m_freem(m);
2399 		splx(s);
2400 		return;
2401 	}
2402 
2403 	sockaddr_in_init(&rsvp_src, &ip->ip_src, 0);
2404 
2405 	if (rsvpdebug && m)
2406 		printf("rsvp_input: m->m_len = %d, sbspace() = %d\n",
2407 		    m->m_len, sbspace(&viftable[vifi].v_rsvpd->so_rcv));
2408 
2409 	if (socket_send(viftable[vifi].v_rsvpd, m, &rsvp_src) < 0)
2410 		if (rsvpdebug)
2411 			printf("rsvp_input: Failed to append to socket\n");
2412 	else
2413 		if (rsvpdebug)
2414 			printf("rsvp_input: send packet up\n");
2415 
2416 	splx(s);
2417 }
2418 #endif /* RSVP_ISI */
2419 
2420 /*
2421  * Code for bandwidth monitors
2422  */
2423 
2424 /*
2425  * Define common interface for timeval-related methods
2426  */
2427 #define	BW_TIMEVALCMP(tvp, uvp, cmp) timercmp((tvp), (uvp), cmp)
2428 #define	BW_TIMEVALDECR(vvp, uvp) timersub((vvp), (uvp), (vvp))
2429 #define	BW_TIMEVALADD(vvp, uvp) timeradd((vvp), (uvp), (vvp))
2430 
2431 static uint32_t
2432 compute_bw_meter_flags(struct bw_upcall *req)
2433 {
2434     uint32_t flags = 0;
2435 
2436     if (req->bu_flags & BW_UPCALL_UNIT_PACKETS)
2437 	flags |= BW_METER_UNIT_PACKETS;
2438     if (req->bu_flags & BW_UPCALL_UNIT_BYTES)
2439 	flags |= BW_METER_UNIT_BYTES;
2440     if (req->bu_flags & BW_UPCALL_GEQ)
2441 	flags |= BW_METER_GEQ;
2442     if (req->bu_flags & BW_UPCALL_LEQ)
2443 	flags |= BW_METER_LEQ;
2444 
2445     return flags;
2446 }
2447 
2448 /*
2449  * Add a bw_meter entry
2450  */
2451 static int
2452 add_bw_upcall(struct bw_upcall *req)
2453 {
2454     int s;
2455     struct mfc *mfc;
2456     struct timeval delta = { BW_UPCALL_THRESHOLD_INTERVAL_MIN_SEC,
2457 		BW_UPCALL_THRESHOLD_INTERVAL_MIN_USEC };
2458     struct timeval now;
2459     struct bw_meter *x;
2460     uint32_t flags;
2461 
2462     if (!(mrt_api_config & MRT_MFC_BW_UPCALL))
2463 	return EOPNOTSUPP;
2464 
2465     /* Test if the flags are valid */
2466     if (!(req->bu_flags & (BW_UPCALL_UNIT_PACKETS | BW_UPCALL_UNIT_BYTES)))
2467 	return EINVAL;
2468     if (!(req->bu_flags & (BW_UPCALL_GEQ | BW_UPCALL_LEQ)))
2469 	return EINVAL;
2470     if ((req->bu_flags & (BW_UPCALL_GEQ | BW_UPCALL_LEQ))
2471 	    == (BW_UPCALL_GEQ | BW_UPCALL_LEQ))
2472 	return EINVAL;
2473 
2474     /* Test if the threshold time interval is valid */
2475     if (BW_TIMEVALCMP(&req->bu_threshold.b_time, &delta, <))
2476 	return EINVAL;
2477 
2478     flags = compute_bw_meter_flags(req);
2479 
2480     /*
2481      * Find if we have already same bw_meter entry
2482      */
2483     s = splsoftnet();
2484     mfc = mfc_find(&req->bu_src, &req->bu_dst);
2485     if (mfc == NULL) {
2486 	splx(s);
2487 	return EADDRNOTAVAIL;
2488     }
2489     for (x = mfc->mfc_bw_meter; x != NULL; x = x->bm_mfc_next) {
2490 	if ((BW_TIMEVALCMP(&x->bm_threshold.b_time,
2491 			   &req->bu_threshold.b_time, ==)) &&
2492 	    (x->bm_threshold.b_packets == req->bu_threshold.b_packets) &&
2493 	    (x->bm_threshold.b_bytes == req->bu_threshold.b_bytes) &&
2494 	    (x->bm_flags & BW_METER_USER_FLAGS) == flags)  {
2495 	    splx(s);
2496 	    return 0;		/* XXX Already installed */
2497 	}
2498     }
2499 
2500     /* Allocate the new bw_meter entry */
2501     x = kmem_intr_alloc(sizeof(*x), KM_NOSLEEP);
2502     if (x == NULL) {
2503 	splx(s);
2504 	return ENOBUFS;
2505     }
2506 
2507     /* Set the new bw_meter entry */
2508     x->bm_threshold.b_time = req->bu_threshold.b_time;
2509     microtime(&now);
2510     x->bm_start_time = now;
2511     x->bm_threshold.b_packets = req->bu_threshold.b_packets;
2512     x->bm_threshold.b_bytes = req->bu_threshold.b_bytes;
2513     x->bm_measured.b_packets = 0;
2514     x->bm_measured.b_bytes = 0;
2515     x->bm_flags = flags;
2516     x->bm_time_next = NULL;
2517     x->bm_time_hash = BW_METER_BUCKETS;
2518 
2519     /* Add the new bw_meter entry to the front of entries for this MFC */
2520     x->bm_mfc = mfc;
2521     x->bm_mfc_next = mfc->mfc_bw_meter;
2522     mfc->mfc_bw_meter = x;
2523     schedule_bw_meter(x, &now);
2524     splx(s);
2525 
2526     return 0;
2527 }
2528 
2529 static void
2530 free_bw_list(struct bw_meter *list)
2531 {
2532     while (list != NULL) {
2533 	struct bw_meter *x = list;
2534 
2535 	list = list->bm_mfc_next;
2536 	unschedule_bw_meter(x);
2537 	kmem_free(x, sizeof(*x));
2538     }
2539 }
2540 
2541 /*
2542  * Delete one or multiple bw_meter entries
2543  */
2544 static int
2545 del_bw_upcall(struct bw_upcall *req)
2546 {
2547     int s;
2548     struct mfc *mfc;
2549     struct bw_meter *x;
2550 
2551     if (!(mrt_api_config & MRT_MFC_BW_UPCALL))
2552 	return EOPNOTSUPP;
2553 
2554     s = splsoftnet();
2555     /* Find the corresponding MFC entry */
2556     mfc = mfc_find(&req->bu_src, &req->bu_dst);
2557     if (mfc == NULL) {
2558 	splx(s);
2559 	return EADDRNOTAVAIL;
2560     } else if (req->bu_flags & BW_UPCALL_DELETE_ALL) {
2561 	/*
2562 	 * Delete all bw_meter entries for this mfc
2563 	 */
2564 	struct bw_meter *list;
2565 
2566 	list = mfc->mfc_bw_meter;
2567 	mfc->mfc_bw_meter = NULL;
2568 	free_bw_list(list);
2569 	splx(s);
2570 	return 0;
2571     } else {			/* Delete a single bw_meter entry */
2572 	struct bw_meter *prev;
2573 	uint32_t flags = 0;
2574 
2575 	flags = compute_bw_meter_flags(req);
2576 
2577 	/* Find the bw_meter entry to delete */
2578 	for (prev = NULL, x = mfc->mfc_bw_meter; x != NULL;
2579 	     prev = x, x = x->bm_mfc_next) {
2580 	    if ((BW_TIMEVALCMP(&x->bm_threshold.b_time,
2581 			       &req->bu_threshold.b_time, ==)) &&
2582 		(x->bm_threshold.b_packets == req->bu_threshold.b_packets) &&
2583 		(x->bm_threshold.b_bytes == req->bu_threshold.b_bytes) &&
2584 		(x->bm_flags & BW_METER_USER_FLAGS) == flags)
2585 		break;
2586 	}
2587 	if (x != NULL) { /* Delete entry from the list for this MFC */
2588 	    if (prev != NULL)
2589 		prev->bm_mfc_next = x->bm_mfc_next;	/* remove from middle*/
2590 	    else
2591 		x->bm_mfc->mfc_bw_meter = x->bm_mfc_next;/* new head of list */
2592 
2593 	    unschedule_bw_meter(x);
2594 	    splx(s);
2595 	    /* Free the bw_meter entry */
2596 	    kmem_free(x, sizeof(*x));
2597 	    return 0;
2598 	} else {
2599 	    splx(s);
2600 	    return EINVAL;
2601 	}
2602     }
2603     /* NOTREACHED */
2604 }
2605 
2606 /*
2607  * Perform bandwidth measurement processing that may result in an upcall
2608  */
2609 static void
2610 bw_meter_receive_packet(struct bw_meter *x, int plen, struct timeval *nowp)
2611 {
2612     struct timeval delta;
2613 
2614     delta = *nowp;
2615     BW_TIMEVALDECR(&delta, &x->bm_start_time);
2616 
2617     if (x->bm_flags & BW_METER_GEQ) {
2618 	/*
2619 	 * Processing for ">=" type of bw_meter entry
2620 	 */
2621 	if (BW_TIMEVALCMP(&delta, &x->bm_threshold.b_time, >)) {
2622 	    /* Reset the bw_meter entry */
2623 	    x->bm_start_time = *nowp;
2624 	    x->bm_measured.b_packets = 0;
2625 	    x->bm_measured.b_bytes = 0;
2626 	    x->bm_flags &= ~BW_METER_UPCALL_DELIVERED;
2627 	}
2628 
2629 	/* Record that a packet is received */
2630 	x->bm_measured.b_packets++;
2631 	x->bm_measured.b_bytes += plen;
2632 
2633 	/*
2634 	 * Test if we should deliver an upcall
2635 	 */
2636 	if (!(x->bm_flags & BW_METER_UPCALL_DELIVERED)) {
2637 	    if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
2638 		 (x->bm_measured.b_packets >= x->bm_threshold.b_packets)) ||
2639 		((x->bm_flags & BW_METER_UNIT_BYTES) &&
2640 		 (x->bm_measured.b_bytes >= x->bm_threshold.b_bytes))) {
2641 		/* Prepare an upcall for delivery */
2642 		bw_meter_prepare_upcall(x, nowp);
2643 		x->bm_flags |= BW_METER_UPCALL_DELIVERED;
2644 	    }
2645 	}
2646     } else if (x->bm_flags & BW_METER_LEQ) {
2647 	/*
2648 	 * Processing for "<=" type of bw_meter entry
2649 	 */
2650 	if (BW_TIMEVALCMP(&delta, &x->bm_threshold.b_time, >)) {
2651 	    /*
2652 	     * We are behind time with the multicast forwarding table
2653 	     * scanning for "<=" type of bw_meter entries, so test now
2654 	     * if we should deliver an upcall.
2655 	     */
2656 	    if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
2657 		 (x->bm_measured.b_packets <= x->bm_threshold.b_packets)) ||
2658 		((x->bm_flags & BW_METER_UNIT_BYTES) &&
2659 		 (x->bm_measured.b_bytes <= x->bm_threshold.b_bytes))) {
2660 		/* Prepare an upcall for delivery */
2661 		bw_meter_prepare_upcall(x, nowp);
2662 	    }
2663 	    /* Reschedule the bw_meter entry */
2664 	    unschedule_bw_meter(x);
2665 	    schedule_bw_meter(x, nowp);
2666 	}
2667 
2668 	/* Record that a packet is received */
2669 	x->bm_measured.b_packets++;
2670 	x->bm_measured.b_bytes += plen;
2671 
2672 	/*
2673 	 * Test if we should restart the measuring interval
2674 	 */
2675 	if ((x->bm_flags & BW_METER_UNIT_PACKETS &&
2676 	     x->bm_measured.b_packets <= x->bm_threshold.b_packets) ||
2677 	    (x->bm_flags & BW_METER_UNIT_BYTES &&
2678 	     x->bm_measured.b_bytes <= x->bm_threshold.b_bytes)) {
2679 	    /* Don't restart the measuring interval */
2680 	} else {
2681 	    /* Do restart the measuring interval */
2682 	    /*
2683 	     * XXX: note that we don't unschedule and schedule, because this
2684 	     * might be too much overhead per packet. Instead, when we process
2685 	     * all entries for a given timer hash bin, we check whether it is
2686 	     * really a timeout. If not, we reschedule at that time.
2687 	     */
2688 	    x->bm_start_time = *nowp;
2689 	    x->bm_measured.b_packets = 0;
2690 	    x->bm_measured.b_bytes = 0;
2691 	    x->bm_flags &= ~BW_METER_UPCALL_DELIVERED;
2692 	}
2693     }
2694 }
2695 
2696 /*
2697  * Prepare a bandwidth-related upcall
2698  */
2699 static void
2700 bw_meter_prepare_upcall(struct bw_meter *x, struct timeval *nowp)
2701 {
2702     struct timeval delta;
2703     struct bw_upcall *u;
2704 
2705     /*
2706      * Compute the measured time interval
2707      */
2708     delta = *nowp;
2709     BW_TIMEVALDECR(&delta, &x->bm_start_time);
2710 
2711     /*
2712      * If there are too many pending upcalls, deliver them now
2713      */
2714     if (bw_upcalls_n >= BW_UPCALLS_MAX)
2715 	bw_upcalls_send();
2716 
2717     /*
2718      * Set the bw_upcall entry
2719      */
2720     u = &bw_upcalls[bw_upcalls_n++];
2721     u->bu_src = x->bm_mfc->mfc_origin;
2722     u->bu_dst = x->bm_mfc->mfc_mcastgrp;
2723     u->bu_threshold.b_time = x->bm_threshold.b_time;
2724     u->bu_threshold.b_packets = x->bm_threshold.b_packets;
2725     u->bu_threshold.b_bytes = x->bm_threshold.b_bytes;
2726     u->bu_measured.b_time = delta;
2727     u->bu_measured.b_packets = x->bm_measured.b_packets;
2728     u->bu_measured.b_bytes = x->bm_measured.b_bytes;
2729     u->bu_flags = 0;
2730     if (x->bm_flags & BW_METER_UNIT_PACKETS)
2731 	u->bu_flags |= BW_UPCALL_UNIT_PACKETS;
2732     if (x->bm_flags & BW_METER_UNIT_BYTES)
2733 	u->bu_flags |= BW_UPCALL_UNIT_BYTES;
2734     if (x->bm_flags & BW_METER_GEQ)
2735 	u->bu_flags |= BW_UPCALL_GEQ;
2736     if (x->bm_flags & BW_METER_LEQ)
2737 	u->bu_flags |= BW_UPCALL_LEQ;
2738 }
2739 
2740 /*
2741  * Send the pending bandwidth-related upcalls
2742  */
2743 static void
2744 bw_upcalls_send(void)
2745 {
2746     struct mbuf *m;
2747     int len = bw_upcalls_n * sizeof(bw_upcalls[0]);
2748     struct sockaddr_in k_igmpsrc = {
2749 	    .sin_len = sizeof(k_igmpsrc),
2750 	    .sin_family = AF_INET,
2751     };
2752     static struct igmpmsg igmpmsg = { 0,		/* unused1 */
2753 				      0,		/* unused2 */
2754 				      IGMPMSG_BW_UPCALL,/* im_msgtype */
2755 				      0,		/* im_mbz  */
2756 				      0,		/* im_vif  */
2757 				      0,		/* unused3 */
2758 				      { 0 },		/* im_src  */
2759 				      { 0 } };		/* im_dst  */
2760 
2761     if (bw_upcalls_n == 0)
2762 	return;			/* No pending upcalls */
2763 
2764     bw_upcalls_n = 0;
2765 
2766     /*
2767      * Allocate a new mbuf, initialize it with the header and
2768      * the payload for the pending calls.
2769      */
2770     MGETHDR(m, M_DONTWAIT, MT_HEADER);
2771     if (m == NULL) {
2772 	log(LOG_WARNING, "bw_upcalls_send: cannot allocate mbuf\n");
2773 	return;
2774     }
2775 
2776     m->m_len = m->m_pkthdr.len = 0;
2777     m_copyback(m, 0, sizeof(struct igmpmsg), (void *)&igmpmsg);
2778     m_copyback(m, sizeof(struct igmpmsg), len, (void *)&bw_upcalls[0]);
2779 
2780     /*
2781      * Send the upcalls
2782      * XXX do we need to set the address in k_igmpsrc ?
2783      */
2784     mrtstat.mrts_upcalls++;
2785     if (socket_send(ip_mrouter, m, &k_igmpsrc) < 0) {
2786 	log(LOG_WARNING, "bw_upcalls_send: ip_mrouter socket queue full\n");
2787 	++mrtstat.mrts_upq_sockfull;
2788     }
2789 }
2790 
2791 /*
2792  * Compute the timeout hash value for the bw_meter entries
2793  */
2794 #define	BW_METER_TIMEHASH(bw_meter, hash)				\
2795     do {								\
2796 	struct timeval next_timeval = (bw_meter)->bm_start_time;	\
2797 									\
2798 	BW_TIMEVALADD(&next_timeval, &(bw_meter)->bm_threshold.b_time); \
2799 	(hash) = next_timeval.tv_sec;					\
2800 	if (next_timeval.tv_usec)					\
2801 	    (hash)++; /* XXX: make sure we don't timeout early */	\
2802 	(hash) %= BW_METER_BUCKETS;					\
2803     } while (/*CONSTCOND*/ 0)
2804 
2805 /*
2806  * Schedule a timer to process periodically bw_meter entry of type "<="
2807  * by linking the entry in the proper hash bucket.
2808  */
2809 static void
2810 schedule_bw_meter(struct bw_meter *x, struct timeval *nowp)
2811 {
2812     int time_hash;
2813 
2814     if (!(x->bm_flags & BW_METER_LEQ))
2815 	return;		/* XXX: we schedule timers only for "<=" entries */
2816 
2817     /*
2818      * Reset the bw_meter entry
2819      */
2820     x->bm_start_time = *nowp;
2821     x->bm_measured.b_packets = 0;
2822     x->bm_measured.b_bytes = 0;
2823     x->bm_flags &= ~BW_METER_UPCALL_DELIVERED;
2824 
2825     /*
2826      * Compute the timeout hash value and insert the entry
2827      */
2828     BW_METER_TIMEHASH(x, time_hash);
2829     x->bm_time_next = bw_meter_timers[time_hash];
2830     bw_meter_timers[time_hash] = x;
2831     x->bm_time_hash = time_hash;
2832 }
2833 
2834 /*
2835  * Unschedule the periodic timer that processes bw_meter entry of type "<="
2836  * by removing the entry from the proper hash bucket.
2837  */
2838 static void
2839 unschedule_bw_meter(struct bw_meter *x)
2840 {
2841     int time_hash;
2842     struct bw_meter *prev, *tmp;
2843 
2844     if (!(x->bm_flags & BW_METER_LEQ))
2845 	return;		/* XXX: we schedule timers only for "<=" entries */
2846 
2847     /*
2848      * Compute the timeout hash value and delete the entry
2849      */
2850     time_hash = x->bm_time_hash;
2851     if (time_hash >= BW_METER_BUCKETS)
2852 	return;		/* Entry was not scheduled */
2853 
2854     for (prev = NULL, tmp = bw_meter_timers[time_hash];
2855 	     tmp != NULL; prev = tmp, tmp = tmp->bm_time_next)
2856 	if (tmp == x)
2857 	    break;
2858 
2859     if (tmp == NULL)
2860 	panic("unschedule_bw_meter: bw_meter entry not found");
2861 
2862     if (prev != NULL)
2863 	prev->bm_time_next = x->bm_time_next;
2864     else
2865 	bw_meter_timers[time_hash] = x->bm_time_next;
2866 
2867     x->bm_time_next = NULL;
2868     x->bm_time_hash = BW_METER_BUCKETS;
2869 }
2870 
2871 /*
2872  * Process all "<=" type of bw_meter that should be processed now,
2873  * and for each entry prepare an upcall if necessary. Each processed
2874  * entry is rescheduled again for the (periodic) processing.
2875  *
2876  * This is run periodically (once per second normally). On each round,
2877  * all the potentially matching entries are in the hash slot that we are
2878  * looking at.
2879  */
2880 static void
2881 bw_meter_process(void)
2882 {
2883     int s;
2884     static uint32_t last_tv_sec;	/* last time we processed this */
2885 
2886     uint32_t loops;
2887     int i;
2888     struct timeval now, process_endtime;
2889 
2890     microtime(&now);
2891     if (last_tv_sec == now.tv_sec)
2892 	return;		/* nothing to do */
2893 
2894     loops = now.tv_sec - last_tv_sec;
2895     last_tv_sec = now.tv_sec;
2896     if (loops > BW_METER_BUCKETS)
2897 	loops = BW_METER_BUCKETS;
2898 
2899     s = splsoftnet();
2900     /*
2901      * Process all bins of bw_meter entries from the one after the last
2902      * processed to the current one. On entry, i points to the last bucket
2903      * visited, so we need to increment i at the beginning of the loop.
2904      */
2905     for (i = (now.tv_sec - loops) % BW_METER_BUCKETS; loops > 0; loops--) {
2906 	struct bw_meter *x, *tmp_list;
2907 
2908 	if (++i >= BW_METER_BUCKETS)
2909 	    i = 0;
2910 
2911 	/* Disconnect the list of bw_meter entries from the bin */
2912 	tmp_list = bw_meter_timers[i];
2913 	bw_meter_timers[i] = NULL;
2914 
2915 	/* Process the list of bw_meter entries */
2916 	while (tmp_list != NULL) {
2917 	    x = tmp_list;
2918 	    tmp_list = tmp_list->bm_time_next;
2919 
2920 	    /* Test if the time interval is over */
2921 	    process_endtime = x->bm_start_time;
2922 	    BW_TIMEVALADD(&process_endtime, &x->bm_threshold.b_time);
2923 	    if (BW_TIMEVALCMP(&process_endtime, &now, >)) {
2924 		/* Not yet: reschedule, but don't reset */
2925 		int time_hash;
2926 
2927 		BW_METER_TIMEHASH(x, time_hash);
2928 		if (time_hash == i && process_endtime.tv_sec == now.tv_sec) {
2929 		    /*
2930 		     * XXX: somehow the bin processing is a bit ahead of time.
2931 		     * Put the entry in the next bin.
2932 		     */
2933 		    if (++time_hash >= BW_METER_BUCKETS)
2934 			time_hash = 0;
2935 		}
2936 		x->bm_time_next = bw_meter_timers[time_hash];
2937 		bw_meter_timers[time_hash] = x;
2938 		x->bm_time_hash = time_hash;
2939 
2940 		continue;
2941 	    }
2942 
2943 	    /*
2944 	     * Test if we should deliver an upcall
2945 	     */
2946 	    if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
2947 		 (x->bm_measured.b_packets <= x->bm_threshold.b_packets)) ||
2948 		((x->bm_flags & BW_METER_UNIT_BYTES) &&
2949 		 (x->bm_measured.b_bytes <= x->bm_threshold.b_bytes))) {
2950 		/* Prepare an upcall for delivery */
2951 		bw_meter_prepare_upcall(x, &now);
2952 	    }
2953 
2954 	    /*
2955 	     * Reschedule for next processing
2956 	     */
2957 	    schedule_bw_meter(x, &now);
2958 	}
2959     }
2960 
2961     /* Send all upcalls that are pending delivery */
2962     bw_upcalls_send();
2963 
2964     splx(s);
2965 }
2966 
2967 /*
2968  * A periodic function for sending all upcalls that are pending delivery
2969  */
2970 static void
2971 expire_bw_upcalls_send(void *unused)
2972 {
2973     int s;
2974 
2975     s = splsoftnet();
2976     bw_upcalls_send();
2977     splx(s);
2978 
2979     callout_reset(&bw_upcalls_ch, BW_UPCALLS_PERIOD,
2980 		  expire_bw_upcalls_send, NULL);
2981 }
2982 
2983 /*
2984  * A periodic function for periodic scanning of the multicast forwarding
2985  * table for processing all "<=" bw_meter entries.
2986  */
2987 static void
2988 expire_bw_meter_process(void *unused)
2989 {
2990     if (mrt_api_config & MRT_MFC_BW_UPCALL)
2991 	bw_meter_process();
2992 
2993     callout_reset(&bw_meter_ch, BW_METER_PERIOD,
2994 		  expire_bw_meter_process, NULL);
2995 }
2996 
2997 /*
2998  * End of bandwidth monitoring code
2999  */
3000 
3001 #ifdef PIM
3002 /*
3003  * Send the packet up to the user daemon, or eventually do kernel encapsulation
3004  */
3005 static int
3006 pim_register_send(struct ip *ip, struct vif *vifp,
3007 	struct mbuf *m, struct mfc *rt)
3008 {
3009     struct mbuf *mb_copy, *mm;
3010 
3011     if (mrtdebug & DEBUG_PIM)
3012         log(LOG_DEBUG, "pim_register_send: \n");
3013 
3014     mb_copy = pim_register_prepare(ip, m);
3015     if (mb_copy == NULL)
3016 	return ENOBUFS;
3017 
3018     /*
3019      * Send all the fragments. Note that the mbuf for each fragment
3020      * is freed by the sending machinery.
3021      */
3022     for (mm = mb_copy; mm; mm = mb_copy) {
3023 	mb_copy = mm->m_nextpkt;
3024 	mm->m_nextpkt = NULL;
3025 	mm = m_pullup(mm, sizeof(struct ip));
3026 	if (mm != NULL) {
3027 	    ip = mtod(mm, struct ip *);
3028 	    if ((mrt_api_config & MRT_MFC_RP) &&
3029 		!in_nullhost(rt->mfc_rp)) {
3030 		pim_register_send_rp(ip, vifp, mm, rt);
3031 	    } else {
3032 		pim_register_send_upcall(ip, vifp, mm, rt);
3033 	    }
3034 	}
3035     }
3036 
3037     return 0;
3038 }
3039 
3040 /*
3041  * Return a copy of the data packet that is ready for PIM Register
3042  * encapsulation.
3043  * XXX: Note that in the returned copy the IP header is a valid one.
3044  */
3045 static struct mbuf *
3046 pim_register_prepare(struct ip *ip, struct mbuf *m)
3047 {
3048     struct mbuf *mb_copy = NULL;
3049     int mtu;
3050 
3051     /* Take care of delayed checksums */
3052     if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
3053 	in_delayed_cksum(m);
3054 	m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4);
3055     }
3056 
3057     /*
3058      * Copy the old packet & pullup its IP header into the
3059      * new mbuf so we can modify it.
3060      */
3061     mb_copy = m_copypacket(m, M_DONTWAIT);
3062     if (mb_copy == NULL)
3063 	return NULL;
3064     mb_copy = m_pullup(mb_copy, ip->ip_hl << 2);
3065     if (mb_copy == NULL)
3066 	return NULL;
3067 
3068     /* take care of the TTL */
3069     ip = mtod(mb_copy, struct ip *);
3070     --ip->ip_ttl;
3071 
3072     /* Compute the MTU after the PIM Register encapsulation */
3073     mtu = 0xffff - sizeof(pim_encap_iphdr) - sizeof(pim_encap_pimhdr);
3074 
3075     if (ntohs(ip->ip_len) <= mtu) {
3076 	/* Turn the IP header into a valid one */
3077 	ip->ip_sum = 0;
3078 	ip->ip_sum = in_cksum(mb_copy, ip->ip_hl << 2);
3079     } else {
3080 	/* Fragment the packet */
3081 	if (ip_fragment(mb_copy, NULL, mtu) != 0) {
3082 	    /* XXX: mb_copy was freed by ip_fragment() */
3083 	    return NULL;
3084 	}
3085     }
3086     return mb_copy;
3087 }
3088 
3089 /*
3090  * Send an upcall with the data packet to the user-level process.
3091  */
3092 static int
3093 pim_register_send_upcall(struct ip *ip, struct vif *vifp,
3094     struct mbuf *mb_copy, struct mfc *rt)
3095 {
3096     struct mbuf *mb_first;
3097     int len = ntohs(ip->ip_len);
3098     struct igmpmsg *im;
3099     struct sockaddr_in k_igmpsrc = {
3100 	    .sin_len = sizeof(k_igmpsrc),
3101 	    .sin_family = AF_INET,
3102     };
3103 
3104     /*
3105      * Add a new mbuf with an upcall header
3106      */
3107     MGETHDR(mb_first, M_DONTWAIT, MT_HEADER);
3108     if (mb_first == NULL) {
3109 	m_freem(mb_copy);
3110 	return ENOBUFS;
3111     }
3112     mb_first->m_data += max_linkhdr;
3113     mb_first->m_pkthdr.len = len + sizeof(struct igmpmsg);
3114     mb_first->m_len = sizeof(struct igmpmsg);
3115     mb_first->m_next = mb_copy;
3116 
3117     /* Send message to routing daemon */
3118     im = mtod(mb_first, struct igmpmsg *);
3119     im->im_msgtype	= IGMPMSG_WHOLEPKT;
3120     im->im_mbz		= 0;
3121     im->im_vif		= vifp - viftable;
3122     im->im_src		= ip->ip_src;
3123     im->im_dst		= ip->ip_dst;
3124 
3125     k_igmpsrc.sin_addr	= ip->ip_src;
3126 
3127     mrtstat.mrts_upcalls++;
3128 
3129     if (socket_send(ip_mrouter, mb_first, &k_igmpsrc) < 0) {
3130 	if (mrtdebug & DEBUG_PIM)
3131 	    log(LOG_WARNING,
3132 		"mcast: pim_register_send_upcall: ip_mrouter socket queue full\n");
3133 	++mrtstat.mrts_upq_sockfull;
3134 	return ENOBUFS;
3135     }
3136 
3137     /* Keep statistics */
3138     pimstat.pims_snd_registers_msgs++;
3139     pimstat.pims_snd_registers_bytes += len;
3140 
3141     return 0;
3142 }
3143 
3144 /*
3145  * Encapsulate the data packet in PIM Register message and send it to the RP.
3146  */
3147 static int
3148 pim_register_send_rp(struct ip *ip, struct vif *vifp,
3149 	struct mbuf *mb_copy, struct mfc *rt)
3150 {
3151     struct mbuf *mb_first;
3152     struct ip *ip_outer;
3153     struct pim_encap_pimhdr *pimhdr;
3154     int len = ntohs(ip->ip_len);
3155     vifi_t vifi = rt->mfc_parent;
3156 
3157     if ((vifi >= numvifs) || in_nullhost(viftable[vifi].v_lcl_addr)) {
3158 	m_freem(mb_copy);
3159 	return EADDRNOTAVAIL;		/* The iif vif is invalid */
3160     }
3161 
3162     /*
3163      * Add a new mbuf with the encapsulating header
3164      */
3165     MGETHDR(mb_first, M_DONTWAIT, MT_HEADER);
3166     if (mb_first == NULL) {
3167 	m_freem(mb_copy);
3168 	return ENOBUFS;
3169     }
3170     mb_first->m_data += max_linkhdr;
3171     mb_first->m_len = sizeof(pim_encap_iphdr) + sizeof(pim_encap_pimhdr);
3172     mb_first->m_next = mb_copy;
3173 
3174     mb_first->m_pkthdr.len = len + mb_first->m_len;
3175 
3176     /*
3177      * Fill in the encapsulating IP and PIM header
3178      */
3179     ip_outer = mtod(mb_first, struct ip *);
3180     *ip_outer = pim_encap_iphdr;
3181      if (mb_first->m_pkthdr.len < IP_MINFRAGSIZE)
3182 	ip_outer->ip_id = 0;
3183     else
3184 	ip_outer->ip_id = ip_newid(NULL);
3185     ip_outer->ip_len = htons(len + sizeof(pim_encap_iphdr) +
3186 			     sizeof(pim_encap_pimhdr));
3187     ip_outer->ip_src = viftable[vifi].v_lcl_addr;
3188     ip_outer->ip_dst = rt->mfc_rp;
3189     /*
3190      * Copy the inner header TOS to the outer header, and take care of the
3191      * IP_DF bit.
3192      */
3193     ip_outer->ip_tos = ip->ip_tos;
3194     if (ntohs(ip->ip_off) & IP_DF)
3195 	ip_outer->ip_off |= htons(IP_DF);
3196     pimhdr = (struct pim_encap_pimhdr *)((char *)ip_outer
3197 					 + sizeof(pim_encap_iphdr));
3198     *pimhdr = pim_encap_pimhdr;
3199     /* If the iif crosses a border, set the Border-bit */
3200     if (rt->mfc_flags[vifi] & MRT_MFC_FLAGS_BORDER_VIF & mrt_api_config)
3201 	pimhdr->flags |= htonl(PIM_BORDER_REGISTER);
3202 
3203     mb_first->m_data += sizeof(pim_encap_iphdr);
3204     pimhdr->pim.pim_cksum = in_cksum(mb_first, sizeof(pim_encap_pimhdr));
3205     mb_first->m_data -= sizeof(pim_encap_iphdr);
3206 
3207     if (vifp->v_rate_limit == 0)
3208 	tbf_send_packet(vifp, mb_first);
3209     else
3210 	tbf_control(vifp, mb_first, ip, ntohs(ip_outer->ip_len));
3211 
3212     /* Keep statistics */
3213     pimstat.pims_snd_registers_msgs++;
3214     pimstat.pims_snd_registers_bytes += len;
3215 
3216     return 0;
3217 }
3218 
3219 /*
3220  * PIM-SMv2 and PIM-DM messages processing.
3221  * Receives and verifies the PIM control messages, and passes them
3222  * up to the listening socket, using rip_input().
3223  * The only message with special processing is the PIM_REGISTER message
3224  * (used by PIM-SM): the PIM header is stripped off, and the inner packet
3225  * is passed to if_simloop().
3226  */
3227 void
3228 pim_input(struct mbuf *m, ...)
3229 {
3230     struct ip *ip = mtod(m, struct ip *);
3231     struct pim *pim;
3232     int minlen;
3233     int datalen;
3234     int ip_tos;
3235     int proto;
3236     int iphlen;
3237     va_list ap;
3238 
3239     va_start(ap, m);
3240     iphlen = va_arg(ap, int);
3241     proto = va_arg(ap, int);
3242     va_end(ap);
3243 
3244     datalen = ntohs(ip->ip_len) - iphlen;
3245 
3246     /* Keep statistics */
3247     pimstat.pims_rcv_total_msgs++;
3248     pimstat.pims_rcv_total_bytes += datalen;
3249 
3250     /*
3251      * Validate lengths
3252      */
3253     if (datalen < PIM_MINLEN) {
3254 	pimstat.pims_rcv_tooshort++;
3255 	log(LOG_ERR, "pim_input: packet size too small %d from %lx\n",
3256 	    datalen, (u_long)ip->ip_src.s_addr);
3257 	m_freem(m);
3258 	return;
3259     }
3260 
3261     /*
3262      * If the packet is at least as big as a REGISTER, go agead
3263      * and grab the PIM REGISTER header size, to avoid another
3264      * possible m_pullup() later.
3265      *
3266      * PIM_MINLEN       == pimhdr + u_int32_t == 4 + 4 = 8
3267      * PIM_REG_MINLEN   == pimhdr + reghdr + encap_iphdr == 4 + 4 + 20 = 28
3268      */
3269     minlen = iphlen + (datalen >= PIM_REG_MINLEN ? PIM_REG_MINLEN : PIM_MINLEN);
3270     /*
3271      * Get the IP and PIM headers in contiguous memory, and
3272      * possibly the PIM REGISTER header.
3273      */
3274     if ((m->m_flags & M_EXT || m->m_len < minlen) &&
3275 	(m = m_pullup(m, minlen)) == NULL) {
3276 	log(LOG_ERR, "pim_input: m_pullup failure\n");
3277 	return;
3278     }
3279     /* m_pullup() may have given us a new mbuf so reset ip. */
3280     ip = mtod(m, struct ip *);
3281     ip_tos = ip->ip_tos;
3282 
3283     /* adjust mbuf to point to the PIM header */
3284     m->m_data += iphlen;
3285     m->m_len  -= iphlen;
3286     pim = mtod(m, struct pim *);
3287 
3288     /*
3289      * Validate checksum. If PIM REGISTER, exclude the data packet.
3290      *
3291      * XXX: some older PIMv2 implementations don't make this distinction,
3292      * so for compatibility reason perform the checksum over part of the
3293      * message, and if error, then over the whole message.
3294      */
3295     if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER && in_cksum(m, PIM_MINLEN) == 0) {
3296 	/* do nothing, checksum okay */
3297     } else if (in_cksum(m, datalen)) {
3298 	pimstat.pims_rcv_badsum++;
3299 	if (mrtdebug & DEBUG_PIM)
3300 	    log(LOG_DEBUG, "pim_input: invalid checksum\n");
3301 	m_freem(m);
3302 	return;
3303     }
3304 
3305     /* PIM version check */
3306     if (PIM_VT_V(pim->pim_vt) < PIM_VERSION) {
3307 	pimstat.pims_rcv_badversion++;
3308 	log(LOG_ERR, "pim_input: incorrect version %d, expecting %d\n",
3309 	    PIM_VT_V(pim->pim_vt), PIM_VERSION);
3310 	m_freem(m);
3311 	return;
3312     }
3313 
3314     /* restore mbuf back to the outer IP */
3315     m->m_data -= iphlen;
3316     m->m_len  += iphlen;
3317 
3318     if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER) {
3319 	/*
3320 	 * Since this is a REGISTER, we'll make a copy of the register
3321 	 * headers ip + pim + u_int32 + encap_ip, to be passed up to the
3322 	 * routing daemon.
3323 	 */
3324 	int s;
3325 	struct sockaddr_in dst = {
3326 		.sin_len = sizeof(dst),
3327 		.sin_family = AF_INET,
3328 	};
3329 	struct mbuf *mcp;
3330 	struct ip *encap_ip;
3331 	u_int32_t *reghdr;
3332 	struct ifnet *vifp;
3333 
3334 	s = splsoftnet();
3335 	if ((reg_vif_num >= numvifs) || (reg_vif_num == VIFI_INVALID)) {
3336 	    splx(s);
3337 	    if (mrtdebug & DEBUG_PIM)
3338 		log(LOG_DEBUG,
3339 		    "pim_input: register vif not set: %d\n", reg_vif_num);
3340 	    m_freem(m);
3341 	    return;
3342 	}
3343 	/* XXX need refcnt? */
3344 	vifp = viftable[reg_vif_num].v_ifp;
3345 	splx(s);
3346 
3347 	/*
3348 	 * Validate length
3349 	 */
3350 	if (datalen < PIM_REG_MINLEN) {
3351 	    pimstat.pims_rcv_tooshort++;
3352 	    pimstat.pims_rcv_badregisters++;
3353 	    log(LOG_ERR,
3354 		"pim_input: register packet size too small %d from %lx\n",
3355 		datalen, (u_long)ip->ip_src.s_addr);
3356 	    m_freem(m);
3357 	    return;
3358 	}
3359 
3360 	reghdr = (u_int32_t *)(pim + 1);
3361 	encap_ip = (struct ip *)(reghdr + 1);
3362 
3363 	if (mrtdebug & DEBUG_PIM) {
3364 	    log(LOG_DEBUG,
3365 		"pim_input[register], encap_ip: %lx -> %lx, encap_ip len %d\n",
3366 		(u_long)ntohl(encap_ip->ip_src.s_addr),
3367 		(u_long)ntohl(encap_ip->ip_dst.s_addr),
3368 		ntohs(encap_ip->ip_len));
3369 	}
3370 
3371 	/* verify the version number of the inner packet */
3372 	if (encap_ip->ip_v != IPVERSION) {
3373 	    pimstat.pims_rcv_badregisters++;
3374 	    if (mrtdebug & DEBUG_PIM) {
3375 		log(LOG_DEBUG, "pim_input: invalid IP version (%d) "
3376 		    "of the inner packet\n", encap_ip->ip_v);
3377 	    }
3378 	    m_freem(m);
3379 	    return;
3380 	}
3381 
3382 	/* verify the inner packet is destined to a mcast group */
3383 	if (!IN_MULTICAST(encap_ip->ip_dst.s_addr)) {
3384 	    pimstat.pims_rcv_badregisters++;
3385 	    if (mrtdebug & DEBUG_PIM)
3386 		log(LOG_DEBUG,
3387 		    "pim_input: inner packet of register is not "
3388 		    "multicast %lx\n",
3389 		    (u_long)ntohl(encap_ip->ip_dst.s_addr));
3390 	    m_freem(m);
3391 	    return;
3392 	}
3393 
3394 	/* If a NULL_REGISTER, pass it to the daemon */
3395 	if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
3396 	    goto pim_input_to_daemon;
3397 
3398 	/*
3399 	 * Copy the TOS from the outer IP header to the inner IP header.
3400 	 */
3401 	if (encap_ip->ip_tos != ip_tos) {
3402 	    /* Outer TOS -> inner TOS */
3403 	    encap_ip->ip_tos = ip_tos;
3404 	    /* Recompute the inner header checksum. Sigh... */
3405 
3406 	    /* adjust mbuf to point to the inner IP header */
3407 	    m->m_data += (iphlen + PIM_MINLEN);
3408 	    m->m_len  -= (iphlen + PIM_MINLEN);
3409 
3410 	    encap_ip->ip_sum = 0;
3411 	    encap_ip->ip_sum = in_cksum(m, encap_ip->ip_hl << 2);
3412 
3413 	    /* restore mbuf to point back to the outer IP header */
3414 	    m->m_data -= (iphlen + PIM_MINLEN);
3415 	    m->m_len  += (iphlen + PIM_MINLEN);
3416 	}
3417 
3418 	/*
3419 	 * Decapsulate the inner IP packet and loopback to forward it
3420 	 * as a normal multicast packet. Also, make a copy of the
3421 	 *     outer_iphdr + pimhdr + reghdr + encap_iphdr
3422 	 * to pass to the daemon later, so it can take the appropriate
3423 	 * actions (e.g., send back PIM_REGISTER_STOP).
3424 	 * XXX: here m->m_data points to the outer IP header.
3425 	 */
3426 	mcp = m_copym(m, 0, iphlen + PIM_REG_MINLEN, M_DONTWAIT);
3427 	if (mcp == NULL) {
3428 	    log(LOG_ERR,
3429 		"pim_input: pim register: could not copy register head\n");
3430 	    m_freem(m);
3431 	    return;
3432 	}
3433 
3434 	/* Keep statistics */
3435 	/* XXX: registers_bytes include only the encap. mcast pkt */
3436 	pimstat.pims_rcv_registers_msgs++;
3437 	pimstat.pims_rcv_registers_bytes += ntohs(encap_ip->ip_len);
3438 
3439 	/*
3440 	 * forward the inner ip packet; point m_data at the inner ip.
3441 	 */
3442 	m_adj(m, iphlen + PIM_MINLEN);
3443 
3444 	if (mrtdebug & DEBUG_PIM) {
3445 	    log(LOG_DEBUG,
3446 		"pim_input: forwarding decapsulated register: "
3447 		"src %lx, dst %lx, vif %d\n",
3448 		(u_long)ntohl(encap_ip->ip_src.s_addr),
3449 		(u_long)ntohl(encap_ip->ip_dst.s_addr),
3450 		reg_vif_num);
3451 	}
3452 	/* NB: vifp was collected above; can it change on us? */
3453 	looutput(vifp, m, (struct sockaddr *)&dst, NULL);
3454 
3455 	/* prepare the register head to send to the mrouting daemon */
3456 	m = mcp;
3457     }
3458 
3459 pim_input_to_daemon:
3460     /*
3461      * Pass the PIM message up to the daemon; if it is a Register message,
3462      * pass the 'head' only up to the daemon. This includes the
3463      * outer IP header, PIM header, PIM-Register header and the
3464      * inner IP header.
3465      * XXX: the outer IP header pkt size of a Register is not adjust to
3466      * reflect the fact that the inner multicast data is truncated.
3467      */
3468     rip_input(m, iphlen, proto);
3469 
3470     return;
3471 }
3472 #endif /* PIM */
3473