xref: /netbsd-src/sys/netinet/ip_mroute.c (revision a294b89509dbb1e4f855bcebb4a9ddd1747721e1)
1 /*	$NetBSD: ip_mroute.c,v 1.165 2022/03/15 21:39:59 andvar 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 1.165 2022/03/15 21:39:59 andvar Exp $");
97 
98 #ifdef _KERNEL_OPT
99 #include "opt_inet.h"
100 #include "opt_ipsec.h"
101 #include "opt_pim.h"
102 #endif
103 
104 #ifdef PIM
105 #define _PIM_VT 1
106 #endif
107 
108 #include <sys/param.h>
109 #include <sys/systm.h>
110 #include <sys/callout.h>
111 #include <sys/mbuf.h>
112 #include <sys/socket.h>
113 #include <sys/socketvar.h>
114 #include <sys/errno.h>
115 #include <sys/time.h>
116 #include <sys/kernel.h>
117 #include <sys/kmem.h>
118 #include <sys/ioctl.h>
119 #include <sys/syslog.h>
120 
121 #include <net/if.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/in_offload.h>
128 #include <netinet/ip.h>
129 #include <netinet/ip_var.h>
130 #include <netinet/in_pcb.h>
131 #include <netinet/udp.h>
132 #include <netinet/igmp.h>
133 #include <netinet/igmp_var.h>
134 #include <netinet/ip_mroute.h>
135 #ifdef PIM
136 #include <netinet/pim.h>
137 #include <netinet/pim_var.h>
138 #endif
139 #include <netinet/ip_encap.h>
140 
141 #ifdef IPSEC
142 #include <netipsec/ipsec.h>
143 #include <netipsec/key.h>
144 #endif
145 
146 #define IP_MULTICASTOPTS 0
147 #define	M_PULLUP(m, len)						 \
148 	do {								 \
149 		if ((m) && ((m)->m_flags & M_EXT || (m)->m_len < (len))) \
150 			(m) = m_pullup((m), (len));			 \
151 	} while (/*CONSTCOND*/ 0)
152 
153 /*
154  * Globals.  All but ip_mrouter and ip_mrtproto could be static,
155  * except for netstat or debugging purposes.
156  */
157 struct socket  *ip_mrouter  = NULL;
158 int		ip_mrtproto = IGMP_DVMRP;    /* for netstat only */
159 
160 #define	MFCHASH(a, g)							\
161 	((((a).s_addr >> 20) ^ ((a).s_addr >> 10) ^ (a).s_addr ^	\
162 	  ((g).s_addr >> 20) ^ ((g).s_addr >> 10) ^ (g).s_addr) & mfchash)
163 LIST_HEAD(mfchashhdr, mfc) *mfchashtbl;
164 u_long	mfchash;
165 
166 u_char		nexpire[MFCTBLSIZ];
167 struct vif	viftable[MAXVIFS];
168 struct mrtstat	mrtstat;
169 u_int		mrtdebug = 0;	/* debug level */
170 #define		DEBUG_MFC	0x02
171 #define		DEBUG_FORWARD	0x04
172 #define		DEBUG_EXPIRE	0x08
173 #define		DEBUG_XMIT	0x10
174 #define		DEBUG_PIM	0x20
175 
176 #define		VIFI_INVALID	((vifi_t) -1)
177 
178 u_int tbfdebug = 0;	/* tbf debug level */
179 
180 /* vif attachment using sys/netinet/ip_encap.c */
181 static void vif_input(struct mbuf *, int, int, void *);
182 static int vif_encapcheck(struct mbuf *, int, int, void *);
183 
184 static const struct encapsw vif_encapsw = {
185 	.encapsw4 = {
186 		.pr_input	= vif_input,
187 		.pr_ctlinput	= NULL,
188 	}
189 };
190 
191 #define		EXPIRE_TIMEOUT	(hz / 4)	/* 4x / second */
192 #define		UPCALL_EXPIRE	6		/* number of timeouts */
193 
194 /*
195  * Define the token bucket filter structures
196  */
197 
198 #define		TBF_REPROCESS	(hz / 100)	/* 100x / second */
199 
200 static int get_sg_cnt(struct sioc_sg_req *);
201 static int get_vif_cnt(struct sioc_vif_req *);
202 static int ip_mrouter_init(struct socket *, int);
203 static int set_assert(int);
204 static int add_vif(struct vifctl *);
205 static int del_vif(vifi_t *);
206 static void update_mfc_params(struct mfc *, struct mfcctl2 *);
207 static void init_mfc_params(struct mfc *, struct mfcctl2 *);
208 static void expire_mfc(struct mfc *);
209 static int add_mfc(struct sockopt *);
210 #ifdef UPCALL_TIMING
211 static void collate(struct timeval *);
212 #endif
213 static int del_mfc(struct sockopt *);
214 static int set_api_config(struct sockopt *); /* chose API capabilities */
215 static int socket_send(struct socket *, struct mbuf *, struct sockaddr_in *);
216 static void expire_upcalls(void *);
217 static int ip_mdq(struct mbuf *, struct ifnet *, struct mfc *);
218 static void phyint_send(struct ip *, struct vif *, struct mbuf *);
219 static void encap_send(struct ip *, struct vif *, struct mbuf *);
220 static void tbf_control(struct vif *, struct mbuf *, struct ip *, u_int32_t);
221 static void tbf_queue(struct vif *, struct mbuf *);
222 static void tbf_process_q(struct vif *);
223 static void tbf_reprocess_q(void *);
224 static int tbf_dq_sel(struct vif *, struct ip *);
225 static void tbf_send_packet(struct vif *, struct mbuf *);
226 static void tbf_update_tokens(struct vif *);
227 static int priority(struct vif *, struct ip *);
228 static int ip_mforward_real(struct mbuf *, struct ifnet *);
229 
230 
231 /*
232  * Bandwidth monitoring
233  */
234 static void free_bw_list(struct bw_meter *);
235 static int add_bw_upcall(struct bw_upcall *);
236 static int del_bw_upcall(struct bw_upcall *);
237 static void bw_meter_receive_packet(struct bw_meter *, int , struct timeval *);
238 static void bw_meter_prepare_upcall(struct bw_meter *, struct timeval *);
239 static void bw_upcalls_send(void);
240 static void schedule_bw_meter(struct bw_meter *, struct timeval *);
241 static void unschedule_bw_meter(struct bw_meter *);
242 static void bw_meter_process(void);
243 static void expire_bw_upcalls_send(void *);
244 static void expire_bw_meter_process(void *);
245 
246 #ifdef PIM
247 static int pim_register_send(struct ip *, struct vif *,
248     struct mbuf *, struct mfc *);
249 static int pim_register_send_rp(struct ip *, struct vif *,
250     struct mbuf *, struct mfc *);
251 static int pim_register_send_upcall(struct ip *, struct vif *,
252     struct mbuf *, struct mfc *);
253 static struct mbuf *pim_register_prepare(struct ip *, struct mbuf *);
254 #endif
255 
256 #define	ENCAP_TTL	64
257 #define	ENCAP_PROTO	IPPROTO_IPIP
258 
259 /* prototype IP hdr for encapsulated packets */
260 static const struct ip multicast_encap_iphdr = {
261 	.ip_hl = sizeof(struct ip) >> 2,
262 	.ip_v = IPVERSION,
263 	.ip_len = sizeof(struct ip),
264 	.ip_ttl = ENCAP_TTL,
265 	.ip_p = ENCAP_PROTO,
266 };
267 
268 /*
269  * Bandwidth meter variables and constants
270  */
271 
272 /*
273  * Pending timeouts are stored in a hash table, the key being the
274  * expiration time. Periodically, the entries are analysed and processed.
275  */
276 #define BW_METER_BUCKETS	1024
277 static struct bw_meter *bw_meter_timers[BW_METER_BUCKETS];
278 struct callout bw_meter_ch;
279 #define BW_METER_PERIOD (hz)		/* periodical handling of bw meters */
280 
281 /*
282  * Pending upcalls are stored in a vector which is flushed when
283  * full, or periodically
284  */
285 static struct bw_upcall	bw_upcalls[BW_UPCALLS_MAX];
286 static u_int	bw_upcalls_n; /* # of pending upcalls */
287 struct callout	bw_upcalls_ch;
288 #define BW_UPCALLS_PERIOD (hz)		/* periodical flush of bw upcalls */
289 
290 #ifdef PIM
291 struct pimstat pimstat;
292 
293 /*
294  * Note: the PIM Register encapsulation adds the following in front of a
295  * data packet:
296  *
297  * struct pim_encap_hdr {
298  *     struct ip ip;
299  *     struct pim_encap_pimhdr  pim;
300  * }
301  */
302 
303 struct pim_encap_pimhdr {
304 	struct pim pim;
305 	uint32_t   flags;
306 };
307 
308 static struct ip pim_encap_iphdr = {
309 	.ip_v = IPVERSION,
310 	.ip_hl = sizeof(struct ip) >> 2,
311 	.ip_len = sizeof(struct ip),
312 	.ip_ttl = ENCAP_TTL,
313 	.ip_p = IPPROTO_PIM,
314 };
315 
316 static struct pim_encap_pimhdr pim_encap_pimhdr = {
317     {
318 	PIM_MAKE_VT(PIM_VERSION, PIM_REGISTER), /* PIM vers and message type */
319 	0,			/* reserved */
320 	0,			/* checksum */
321     },
322     0				/* flags */
323 };
324 
325 static struct ifnet multicast_register_if;
326 static vifi_t reg_vif_num = VIFI_INVALID;
327 #endif /* PIM */
328 
329 
330 /*
331  * Private variables.
332  */
333 static vifi_t	   numvifs = 0;
334 
335 static struct callout expire_upcalls_ch;
336 
337 /*
338  * whether or not special PIM assert processing is enabled.
339  */
340 static int pim_assert;
341 /*
342  * Rate limit for assert notification messages, in usec
343  */
344 #define ASSERT_MSG_TIME		3000000
345 
346 /*
347  * Kernel multicast routing API capabilities and setup.
348  * If more API capabilities are added to the kernel, they should be
349  * recorded in `mrt_api_support'.
350  */
351 static const u_int32_t mrt_api_support = (MRT_MFC_FLAGS_DISABLE_WRONGVIF |
352 					  MRT_MFC_FLAGS_BORDER_VIF |
353 					  MRT_MFC_RP |
354 					  MRT_MFC_BW_UPCALL);
355 static u_int32_t mrt_api_config = 0;
356 
357 /*
358  * Find a route for a given origin IP address and Multicast group address
359  * Type of service parameter to be added in the future!!!
360  * Statistics are updated by the caller if needed
361  * (mrtstat.mrts_mfc_lookups and mrtstat.mrts_mfc_misses)
362  */
363 static struct mfc *
mfc_find(struct in_addr * o,struct in_addr * g)364 mfc_find(struct in_addr *o, struct in_addr *g)
365 {
366 	struct mfc *rt;
367 
368 	LIST_FOREACH(rt, &mfchashtbl[MFCHASH(*o, *g)], mfc_hash) {
369 		if (in_hosteq(rt->mfc_origin, *o) &&
370 		    in_hosteq(rt->mfc_mcastgrp, *g) &&
371 		    (rt->mfc_stall == NULL))
372 			break;
373 	}
374 
375 	return rt;
376 }
377 
378 /*
379  * Macros to compute elapsed time efficiently
380  * Borrowed from Van Jacobson's scheduling code
381  */
382 #define TV_DELTA(a, b, delta) do {					\
383 	int xxs;							\
384 	delta = (a).tv_usec - (b).tv_usec;				\
385 	xxs = (a).tv_sec - (b).tv_sec;					\
386 	switch (xxs) {							\
387 	case 2:								\
388 		delta += 1000000;					\
389 		/* fall through */					\
390 	case 1:								\
391 		delta += 1000000;					\
392 		/* fall through */					\
393 	case 0:								\
394 		break;							\
395 	default:							\
396 		delta += (1000000 * xxs);				\
397 		break;							\
398 	}								\
399 } while (/*CONSTCOND*/ 0)
400 
401 #ifdef UPCALL_TIMING
402 u_int32_t upcall_data[51];
403 #endif /* UPCALL_TIMING */
404 
405 /*
406  * Handle MRT setsockopt commands to modify the multicast routing tables.
407  */
408 int
ip_mrouter_set(struct socket * so,struct sockopt * sopt)409 ip_mrouter_set(struct socket *so, struct sockopt *sopt)
410 {
411 	int error;
412 	int optval;
413 	struct vifctl vifc;
414 	vifi_t vifi;
415 	struct bw_upcall bwuc;
416 
417 	if (sopt->sopt_name != MRT_INIT && so != ip_mrouter)
418 		error = ENOPROTOOPT;
419 	else {
420 		switch (sopt->sopt_name) {
421 		case MRT_INIT:
422 			error = sockopt_getint(sopt, &optval);
423 			if (error)
424 				break;
425 
426 			error = ip_mrouter_init(so, optval);
427 			break;
428 		case MRT_DONE:
429 			error = ip_mrouter_done();
430 			break;
431 		case MRT_ADD_VIF:
432 			error = sockopt_get(sopt, &vifc, sizeof(vifc));
433 			if (error)
434 				break;
435 			error = add_vif(&vifc);
436 			break;
437 		case MRT_DEL_VIF:
438 			error = sockopt_get(sopt, &vifi, sizeof(vifi));
439 			if (error)
440 				break;
441 			error = del_vif(&vifi);
442 			break;
443 		case MRT_ADD_MFC:
444 			error = add_mfc(sopt);
445 			break;
446 		case MRT_DEL_MFC:
447 			error = del_mfc(sopt);
448 			break;
449 		case MRT_ASSERT:
450 			error = sockopt_getint(sopt, &optval);
451 			if (error)
452 				break;
453 			error = set_assert(optval);
454 			break;
455 		case MRT_API_CONFIG:
456 			error = set_api_config(sopt);
457 			break;
458 		case MRT_ADD_BW_UPCALL:
459 			error = sockopt_get(sopt, &bwuc, sizeof(bwuc));
460 			if (error)
461 				break;
462 			error = add_bw_upcall(&bwuc);
463 			break;
464 		case MRT_DEL_BW_UPCALL:
465 			error = sockopt_get(sopt, &bwuc, sizeof(bwuc));
466 			if (error)
467 				break;
468 			error = del_bw_upcall(&bwuc);
469 			break;
470 		default:
471 			error = ENOPROTOOPT;
472 			break;
473 		}
474 	}
475 	return error;
476 }
477 
478 /*
479  * Handle MRT getsockopt commands
480  */
481 int
ip_mrouter_get(struct socket * so,struct sockopt * sopt)482 ip_mrouter_get(struct socket *so, struct sockopt *sopt)
483 {
484 	int error;
485 
486 	if (so != ip_mrouter)
487 		error = ENOPROTOOPT;
488 	else {
489 		switch (sopt->sopt_name) {
490 		case MRT_VERSION:
491 			error = sockopt_setint(sopt, 0x0305); /* XXX !!!! */
492 			break;
493 		case MRT_ASSERT:
494 			error = sockopt_setint(sopt, pim_assert);
495 			break;
496 		case MRT_API_SUPPORT:
497 			error = sockopt_set(sopt, &mrt_api_support,
498 			    sizeof(mrt_api_support));
499 			break;
500 		case MRT_API_CONFIG:
501 			error = sockopt_set(sopt, &mrt_api_config,
502 			    sizeof(mrt_api_config));
503 			break;
504 		default:
505 			error = ENOPROTOOPT;
506 			break;
507 		}
508 	}
509 	return error;
510 }
511 
512 /*
513  * Handle ioctl commands to obtain information from the cache
514  */
515 int
mrt_ioctl(struct socket * so,u_long cmd,void * data)516 mrt_ioctl(struct socket *so, u_long cmd, void *data)
517 {
518 	int error;
519 
520 	if (so != ip_mrouter)
521 		error = EINVAL;
522 	else
523 		switch (cmd) {
524 		case SIOCGETVIFCNT:
525 			error = get_vif_cnt((struct sioc_vif_req *)data);
526 			break;
527 		case SIOCGETSGCNT:
528 			error = get_sg_cnt((struct sioc_sg_req *)data);
529 			break;
530 		default:
531 			error = EINVAL;
532 			break;
533 		}
534 
535 	return error;
536 }
537 
538 /*
539  * returns the packet, byte, rpf-failure count for the source group provided
540  */
541 static int
get_sg_cnt(struct sioc_sg_req * req)542 get_sg_cnt(struct sioc_sg_req *req)
543 {
544 	int s;
545 	struct mfc *rt;
546 
547 	s = splsoftnet();
548 	rt = mfc_find(&req->src, &req->grp);
549 	if (rt == NULL) {
550 		splx(s);
551 		req->pktcnt = req->bytecnt = req->wrong_if = 0xffffffff;
552 		return EADDRNOTAVAIL;
553 	}
554 	req->pktcnt = rt->mfc_pkt_cnt;
555 	req->bytecnt = rt->mfc_byte_cnt;
556 	req->wrong_if = rt->mfc_wrong_if;
557 	splx(s);
558 
559 	return 0;
560 }
561 
562 /*
563  * returns the input and output packet and byte counts on the vif provided
564  */
565 static int
get_vif_cnt(struct sioc_vif_req * req)566 get_vif_cnt(struct sioc_vif_req *req)
567 {
568 	vifi_t vifi = req->vifi;
569 
570 	if (vifi >= numvifs)
571 		return EINVAL;
572 
573 	req->icount = viftable[vifi].v_pkt_in;
574 	req->ocount = viftable[vifi].v_pkt_out;
575 	req->ibytes = viftable[vifi].v_bytes_in;
576 	req->obytes = viftable[vifi].v_bytes_out;
577 
578 	return 0;
579 }
580 
581 /*
582  * Enable multicast routing
583  */
584 static int
ip_mrouter_init(struct socket * so,int v)585 ip_mrouter_init(struct socket *so, int v)
586 {
587 	if (mrtdebug)
588 		log(LOG_DEBUG,
589 		    "ip_mrouter_init: so_type = %d, pr_protocol = %d\n",
590 		    so->so_type, so->so_proto->pr_protocol);
591 
592 	if (so->so_type != SOCK_RAW ||
593 	    so->so_proto->pr_protocol != IPPROTO_IGMP)
594 		return EOPNOTSUPP;
595 
596 	if (v != 1)
597 		return EINVAL;
598 
599 	if (ip_mrouter != NULL)
600 		return EADDRINUSE;
601 
602 	ip_mrouter = so;
603 
604 	mfchashtbl = hashinit(MFCTBLSIZ, HASH_LIST, true, &mfchash);
605 	memset((void *)nexpire, 0, sizeof(nexpire));
606 
607 	pim_assert = 0;
608 
609 	callout_init(&expire_upcalls_ch, 0);
610 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
611 		      expire_upcalls, NULL);
612 
613 	callout_init(&bw_upcalls_ch, 0);
614 	callout_reset(&bw_upcalls_ch, BW_UPCALLS_PERIOD,
615 		      expire_bw_upcalls_send, NULL);
616 
617 	callout_init(&bw_meter_ch, 0);
618 	callout_reset(&bw_meter_ch, BW_METER_PERIOD,
619 		      expire_bw_meter_process, NULL);
620 
621 	if (mrtdebug)
622 		log(LOG_DEBUG, "ip_mrouter_init\n");
623 
624 	return 0;
625 }
626 
627 /*
628  * Disable multicast routing
629  */
630 int
ip_mrouter_done(void)631 ip_mrouter_done(void)
632 {
633 	vifi_t vifi;
634 	struct vif *vifp;
635 	int i;
636 	int s;
637 
638 	s = splsoftnet();
639 
640 	/* Clear out all the vifs currently in use. */
641 	for (vifi = 0; vifi < numvifs; vifi++) {
642 		vifp = &viftable[vifi];
643 		if (!in_nullhost(vifp->v_lcl_addr))
644 			reset_vif(vifp);
645 	}
646 
647 	numvifs = 0;
648 	pim_assert = 0;
649 	mrt_api_config = 0;
650 
651 	callout_stop(&expire_upcalls_ch);
652 	callout_stop(&bw_upcalls_ch);
653 	callout_stop(&bw_meter_ch);
654 
655 	/*
656 	 * Free all multicast forwarding cache entries.
657 	 */
658 	for (i = 0; i < MFCTBLSIZ; i++) {
659 		struct mfc *rt, *nrt;
660 
661 		for (rt = LIST_FIRST(&mfchashtbl[i]); rt; rt = nrt) {
662 			nrt = LIST_NEXT(rt, mfc_hash);
663 
664 			expire_mfc(rt);
665 		}
666 	}
667 
668 	memset((void *)nexpire, 0, sizeof(nexpire));
669 	hashdone(mfchashtbl, HASH_LIST, mfchash);
670 	mfchashtbl = NULL;
671 
672 	bw_upcalls_n = 0;
673 	memset(bw_meter_timers, 0, sizeof(bw_meter_timers));
674 
675 	/* Reset de-encapsulation cache. */
676 
677 	ip_mrouter = NULL;
678 
679 	splx(s);
680 
681 	if (mrtdebug)
682 		log(LOG_DEBUG, "ip_mrouter_done\n");
683 
684 	return 0;
685 }
686 
687 void
ip_mrouter_detach(struct ifnet * ifp)688 ip_mrouter_detach(struct ifnet *ifp)
689 {
690 	int vifi, i;
691 	struct vif *vifp;
692 	struct mfc *rt;
693 	struct rtdetq *rte;
694 
695 	/* XXX not sure about side effect to userland routing daemon */
696 	for (vifi = 0; vifi < numvifs; vifi++) {
697 		vifp = &viftable[vifi];
698 		if (vifp->v_ifp == ifp)
699 			reset_vif(vifp);
700 	}
701 	for (i = 0; i < MFCTBLSIZ; i++) {
702 		if (nexpire[i] == 0)
703 			continue;
704 		LIST_FOREACH(rt, &mfchashtbl[i], mfc_hash) {
705 			for (rte = rt->mfc_stall; rte; rte = rte->next) {
706 				if (rte->ifp == ifp)
707 					rte->ifp = NULL;
708 			}
709 		}
710 	}
711 }
712 
713 /*
714  * Set PIM assert processing global
715  */
716 static int
set_assert(int i)717 set_assert(int i)
718 {
719 	pim_assert = !!i;
720 	return 0;
721 }
722 
723 /*
724  * Configure API capabilities
725  */
726 static int
set_api_config(struct sockopt * sopt)727 set_api_config(struct sockopt *sopt)
728 {
729 	u_int32_t apival;
730 	int i, error;
731 
732 	/*
733 	 * We can set the API capabilities only if it is the first operation
734 	 * after MRT_INIT. I.e.:
735 	 *  - there are no vifs installed
736 	 *  - pim_assert is not enabled
737 	 *  - the MFC table is empty
738 	 */
739 	error = sockopt_get(sopt, &apival, sizeof(apival));
740 	if (error)
741 		return error;
742 	if (numvifs > 0)
743 		return EPERM;
744 	if (pim_assert)
745 		return EPERM;
746 	for (i = 0; i < MFCTBLSIZ; i++) {
747 		if (LIST_FIRST(&mfchashtbl[i]) != NULL)
748 			return EPERM;
749 	}
750 
751 	mrt_api_config = apival & mrt_api_support;
752 	return 0;
753 }
754 
755 /*
756  * Add a vif to the vif table
757  */
758 static int
add_vif(struct vifctl * vifcp)759 add_vif(struct vifctl *vifcp)
760 {
761 	struct vif *vifp;
762 	struct ifnet *ifp;
763 	int error, s;
764 	struct sockaddr_in sin;
765 
766 	if (vifcp->vifc_vifi >= MAXVIFS)
767 		return EINVAL;
768 	if (in_nullhost(vifcp->vifc_lcl_addr))
769 		return EADDRNOTAVAIL;
770 
771 	vifp = &viftable[vifcp->vifc_vifi];
772 	if (!in_nullhost(vifp->v_lcl_addr))
773 		return EADDRINUSE;
774 
775 	/* Find the interface with an address in AF_INET family. */
776 #ifdef PIM
777 	if (vifcp->vifc_flags & VIFF_REGISTER) {
778 		/*
779 		 * XXX: Because VIFF_REGISTER does not really need a valid
780 		 * local interface (e.g. it could be 127.0.0.2), we don't
781 		 * check its address.
782 		 */
783 		ifp = NULL;
784 	} else
785 #endif
786 	{
787 		struct ifaddr *ifa;
788 
789 		sockaddr_in_init(&sin, &vifcp->vifc_lcl_addr, 0);
790 		s = pserialize_read_enter();
791 		ifa = ifa_ifwithaddr(sintosa(&sin));
792 		if (ifa == NULL) {
793 			pserialize_read_exit(s);
794 			return EADDRNOTAVAIL;
795 		}
796 		ifp = ifa->ifa_ifp;
797 		/* FIXME NOMPSAFE */
798 		pserialize_read_exit(s);
799 	}
800 
801 	if (vifcp->vifc_flags & VIFF_TUNNEL) {
802 		if (vifcp->vifc_flags & VIFF_SRCRT) {
803 			log(LOG_ERR, "source routed tunnels not supported\n");
804 			return EOPNOTSUPP;
805 		}
806 
807 		/* attach this vif to decapsulator dispatch table */
808 		/*
809 		 * XXX Use addresses in registration so that matching
810 		 * can be done with radix tree in decapsulator.  But,
811 		 * we need to check inner header for multicast, so
812 		 * this requires both radix tree lookup and then a
813 		 * function to check, and this is not supported yet.
814 		 */
815 		error = encap_lock_enter();
816 		if (error)
817 			return error;
818 		vifp->v_encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV4,
819 		    vif_encapcheck, &vif_encapsw, vifp);
820 		encap_lock_exit();
821 		if (!vifp->v_encap_cookie)
822 			return EINVAL;
823 
824 		/* Create a fake encapsulation interface. */
825 		ifp = malloc(sizeof(*ifp), M_MRTABLE, M_WAITOK|M_ZERO);
826 		snprintf(ifp->if_xname, sizeof(ifp->if_xname),
827 			 "mdecap%d", vifcp->vifc_vifi);
828 
829 		/* Prepare cached route entry. */
830 		memset(&vifp->v_route, 0, sizeof(vifp->v_route));
831 #ifdef PIM
832 	} else if (vifcp->vifc_flags & VIFF_REGISTER) {
833 		ifp = &multicast_register_if;
834 		if (mrtdebug)
835 			log(LOG_DEBUG, "Adding a register vif, ifp: %p\n",
836 			    (void *)ifp);
837 		if (reg_vif_num == VIFI_INVALID) {
838 			memset(ifp, 0, sizeof(*ifp));
839 			snprintf(ifp->if_xname, sizeof(ifp->if_xname),
840 				 "register_vif");
841 			ifp->if_flags = IFF_LOOPBACK;
842 			memset(&vifp->v_route, 0, sizeof(vifp->v_route));
843 			reg_vif_num = vifcp->vifc_vifi;
844 		}
845 #endif
846 	} else {
847 		/* Make sure the interface supports multicast. */
848 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
849 			return EOPNOTSUPP;
850 
851 		/* Enable promiscuous reception of all IP multicasts. */
852 		sockaddr_in_init(&sin, &zeroin_addr, 0);
853 		error = if_mcast_op(ifp, SIOCADDMULTI, sintosa(&sin));
854 		if (error)
855 			return error;
856 	}
857 
858 	s = splsoftnet();
859 
860 	/* Define parameters for the tbf structure. */
861 	vifp->tbf_q = NULL;
862 	vifp->tbf_t = &vifp->tbf_q;
863 	microtime(&vifp->tbf_last_pkt_t);
864 	vifp->tbf_n_tok = 0;
865 	vifp->tbf_q_len = 0;
866 	vifp->tbf_max_q_len = MAXQSIZE;
867 
868 	vifp->v_flags = vifcp->vifc_flags;
869 	vifp->v_threshold = vifcp->vifc_threshold;
870 	/* scaling up here allows division by 1024 in critical code */
871 	vifp->v_rate_limit = vifcp->vifc_rate_limit * 1024 / 1000;
872 	vifp->v_lcl_addr = vifcp->vifc_lcl_addr;
873 	vifp->v_rmt_addr = vifcp->vifc_rmt_addr;
874 	vifp->v_ifp = ifp;
875 	/* Initialize per vif pkt counters. */
876 	vifp->v_pkt_in = 0;
877 	vifp->v_pkt_out = 0;
878 	vifp->v_bytes_in = 0;
879 	vifp->v_bytes_out = 0;
880 
881 	callout_init(&vifp->v_repq_ch, 0);
882 
883 	splx(s);
884 
885 	/* Adjust numvifs up if the vifi is higher than numvifs. */
886 	if (numvifs <= vifcp->vifc_vifi)
887 		numvifs = vifcp->vifc_vifi + 1;
888 
889 	if (mrtdebug)
890 		log(LOG_DEBUG, "add_vif #%d, lcladdr %x, %s %x, thresh %x, rate %d\n",
891 		    vifcp->vifc_vifi,
892 		    ntohl(vifcp->vifc_lcl_addr.s_addr),
893 		    (vifcp->vifc_flags & VIFF_TUNNEL) ? "rmtaddr" : "mask",
894 		    ntohl(vifcp->vifc_rmt_addr.s_addr),
895 		    vifcp->vifc_threshold,
896 		    vifcp->vifc_rate_limit);
897 
898 	return 0;
899 }
900 
901 void
reset_vif(struct vif * vifp)902 reset_vif(struct vif *vifp)
903 {
904 	struct mbuf *m, *n;
905 	struct ifnet *ifp;
906 	struct sockaddr_in sin;
907 
908 	callout_stop(&vifp->v_repq_ch);
909 
910 	/* detach this vif from decapsulator dispatch table */
911 	encap_lock_enter();
912 	encap_detach(vifp->v_encap_cookie);
913 	encap_lock_exit();
914 	vifp->v_encap_cookie = NULL;
915 
916 	/*
917 	 * Free packets queued at the interface
918 	 */
919 	for (m = vifp->tbf_q; m != NULL; m = n) {
920 		n = m->m_nextpkt;
921 		m_freem(m);
922 	}
923 
924 	if (vifp->v_flags & VIFF_TUNNEL)
925 		free(vifp->v_ifp, M_MRTABLE);
926 	else if (vifp->v_flags & VIFF_REGISTER) {
927 #ifdef PIM
928 		reg_vif_num = VIFI_INVALID;
929 #endif
930 	} else {
931 		sockaddr_in_init(&sin, &zeroin_addr, 0);
932 		ifp = vifp->v_ifp;
933 		if_mcast_op(ifp, SIOCDELMULTI, sintosa(&sin));
934 	}
935 	memset((void *)vifp, 0, sizeof(*vifp));
936 }
937 
938 /*
939  * Delete a vif from the vif table
940  */
941 static int
del_vif(vifi_t * vifip)942 del_vif(vifi_t *vifip)
943 {
944 	struct vif *vifp;
945 	vifi_t vifi;
946 	int s;
947 
948 	if (*vifip >= numvifs)
949 		return EINVAL;
950 
951 	vifp = &viftable[*vifip];
952 	if (in_nullhost(vifp->v_lcl_addr))
953 		return EADDRNOTAVAIL;
954 
955 	s = splsoftnet();
956 
957 	reset_vif(vifp);
958 
959 	/* Adjust numvifs down */
960 	for (vifi = numvifs; vifi > 0; vifi--)
961 		if (!in_nullhost(viftable[vifi - 1].v_lcl_addr))
962 			break;
963 	numvifs = vifi;
964 
965 	splx(s);
966 
967 	if (mrtdebug)
968 		log(LOG_DEBUG, "del_vif %d, numvifs %d\n", *vifip, numvifs);
969 
970 	return 0;
971 }
972 
973 /*
974  * update an mfc entry without resetting counters and S,G addresses.
975  */
976 static void
update_mfc_params(struct mfc * rt,struct mfcctl2 * mfccp)977 update_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp)
978 {
979 	int i;
980 
981 	rt->mfc_parent = mfccp->mfcc_parent;
982 	for (i = 0; i < numvifs; i++) {
983 		rt->mfc_ttls[i] = mfccp->mfcc_ttls[i];
984 		rt->mfc_flags[i] = mfccp->mfcc_flags[i] & mrt_api_config &
985 			MRT_MFC_FLAGS_ALL;
986 	}
987 	/* set the RP address */
988 	if (mrt_api_config & MRT_MFC_RP)
989 		rt->mfc_rp = mfccp->mfcc_rp;
990 	else
991 		rt->mfc_rp = zeroin_addr;
992 }
993 
994 /*
995  * fully initialize an mfc entry from the parameter.
996  */
997 static void
init_mfc_params(struct mfc * rt,struct mfcctl2 * mfccp)998 init_mfc_params(struct mfc *rt, struct mfcctl2 *mfccp)
999 {
1000 	rt->mfc_origin     = mfccp->mfcc_origin;
1001 	rt->mfc_mcastgrp   = mfccp->mfcc_mcastgrp;
1002 
1003 	update_mfc_params(rt, mfccp);
1004 
1005 	/* initialize pkt counters per src-grp */
1006 	rt->mfc_pkt_cnt    = 0;
1007 	rt->mfc_byte_cnt   = 0;
1008 	rt->mfc_wrong_if   = 0;
1009 	timerclear(&rt->mfc_last_assert);
1010 }
1011 
1012 static void
expire_mfc(struct mfc * rt)1013 expire_mfc(struct mfc *rt)
1014 {
1015 	struct rtdetq *rte, *nrte;
1016 
1017 	free_bw_list(rt->mfc_bw_meter);
1018 
1019 	for (rte = rt->mfc_stall; rte != NULL; rte = nrte) {
1020 		nrte = rte->next;
1021 		m_freem(rte->m);
1022 		free(rte, M_MRTABLE);
1023 	}
1024 
1025 	LIST_REMOVE(rt, mfc_hash);
1026 	free(rt, M_MRTABLE);
1027 }
1028 
1029 /*
1030  * Add an mfc entry
1031  */
1032 static int
add_mfc(struct sockopt * sopt)1033 add_mfc(struct sockopt *sopt)
1034 {
1035 	struct mfcctl2 mfcctl2;
1036 	struct mfcctl2 *mfccp;
1037 	struct mfc *rt;
1038 	u_int32_t hash = 0;
1039 	struct rtdetq *rte, *nrte;
1040 	u_short nstl;
1041 	int s;
1042 	int error;
1043 
1044 	/*
1045 	 * select data size depending on API version.
1046 	 */
1047 	mfccp = &mfcctl2;
1048 	memset(&mfcctl2, 0, sizeof(mfcctl2));
1049 
1050 	if (mrt_api_config & MRT_API_FLAGS_ALL)
1051 		error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl2));
1052 	else
1053 		error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl));
1054 
1055 	if (error)
1056 		return error;
1057 
1058 	s = splsoftnet();
1059 	rt = mfc_find(&mfccp->mfcc_origin, &mfccp->mfcc_mcastgrp);
1060 
1061 	/* If an entry already exists, just update the fields */
1062 	if (rt) {
1063 		if (mrtdebug & DEBUG_MFC)
1064 			log(LOG_DEBUG, "add_mfc update o %x g %x p %x\n",
1065 			    ntohl(mfccp->mfcc_origin.s_addr),
1066 			    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1067 			    mfccp->mfcc_parent);
1068 
1069 		update_mfc_params(rt, mfccp);
1070 
1071 		splx(s);
1072 		return 0;
1073 	}
1074 
1075 	/*
1076 	 * Find the entry for which the upcall was made and update
1077 	 */
1078 	nstl = 0;
1079 	hash = MFCHASH(mfccp->mfcc_origin, mfccp->mfcc_mcastgrp);
1080 	LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) {
1081 		if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) &&
1082 		    in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp) &&
1083 		    rt->mfc_stall != NULL) {
1084 			if (nstl++)
1085 				log(LOG_ERR, "add_mfc %s o %x g %x p %x dbx %p\n",
1086 				    "multiple kernel entries",
1087 				    ntohl(mfccp->mfcc_origin.s_addr),
1088 				    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1089 				    mfccp->mfcc_parent, rt->mfc_stall);
1090 
1091 			if (mrtdebug & DEBUG_MFC)
1092 				log(LOG_DEBUG, "add_mfc o %x g %x p %x dbg %p\n",
1093 				    ntohl(mfccp->mfcc_origin.s_addr),
1094 				    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1095 				    mfccp->mfcc_parent, rt->mfc_stall);
1096 
1097 			rte = rt->mfc_stall;
1098 			init_mfc_params(rt, mfccp);
1099 			rt->mfc_stall = NULL;
1100 
1101 			rt->mfc_expire = 0; /* Don't clean this guy up */
1102 			nexpire[hash]--;
1103 
1104 			/* free packets Qed at the end of this entry */
1105 			for (; rte != NULL; rte = nrte) {
1106 				nrte = rte->next;
1107 				if (rte->ifp) {
1108 					ip_mdq(rte->m, rte->ifp, rt);
1109 				}
1110 				m_freem(rte->m);
1111 #ifdef UPCALL_TIMING
1112 				collate(&rte->t);
1113 #endif /* UPCALL_TIMING */
1114 				free(rte, M_MRTABLE);
1115 			}
1116 		}
1117 	}
1118 
1119 	/*
1120 	 * It is possible that an entry is being inserted without an upcall
1121 	 */
1122 	if (nstl == 0) {
1123 		/*
1124 		 * No mfc; make a new one
1125 		 */
1126 		if (mrtdebug & DEBUG_MFC)
1127 			log(LOG_DEBUG, "add_mfc no upcall o %x g %x p %x\n",
1128 			    ntohl(mfccp->mfcc_origin.s_addr),
1129 			    ntohl(mfccp->mfcc_mcastgrp.s_addr),
1130 			    mfccp->mfcc_parent);
1131 
1132 		LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) {
1133 			if (in_hosteq(rt->mfc_origin, mfccp->mfcc_origin) &&
1134 			    in_hosteq(rt->mfc_mcastgrp, mfccp->mfcc_mcastgrp)) {
1135 				init_mfc_params(rt, mfccp);
1136 				if (rt->mfc_expire)
1137 					nexpire[hash]--;
1138 				rt->mfc_expire = 0;
1139 				break; /* XXX */
1140 			}
1141 		}
1142 		if (rt == NULL) {	/* no upcall, so make a new entry */
1143 			rt = malloc(sizeof(*rt), M_MRTABLE, M_NOWAIT);
1144 			if (rt == NULL) {
1145 				splx(s);
1146 				return ENOBUFS;
1147 			}
1148 
1149 			init_mfc_params(rt, mfccp);
1150 			rt->mfc_expire	= 0;
1151 			rt->mfc_stall	= NULL;
1152 			rt->mfc_bw_meter = NULL;
1153 
1154 			/* insert new entry at head of hash chain */
1155 			LIST_INSERT_HEAD(&mfchashtbl[hash], rt, mfc_hash);
1156 		}
1157 	}
1158 
1159 	splx(s);
1160 	return 0;
1161 }
1162 
1163 #ifdef UPCALL_TIMING
1164 /*
1165  * collect delay statistics on the upcalls
1166  */
1167 static void
collate(struct timeval * t)1168 collate(struct timeval *t)
1169 {
1170 	u_int32_t d;
1171 	struct timeval tp;
1172 	u_int32_t delta;
1173 
1174 	microtime(&tp);
1175 
1176 	if (timercmp(t, &tp, <)) {
1177 		TV_DELTA(tp, *t, delta);
1178 
1179 		d = delta >> 10;
1180 		if (d > 50)
1181 			d = 50;
1182 
1183 		++upcall_data[d];
1184 	}
1185 }
1186 #endif /* UPCALL_TIMING */
1187 
1188 /*
1189  * Delete an mfc entry
1190  */
1191 static int
del_mfc(struct sockopt * sopt)1192 del_mfc(struct sockopt *sopt)
1193 {
1194 	struct mfcctl2 mfcctl2;
1195 	struct mfcctl2 *mfccp;
1196 	struct mfc *rt;
1197 	int s;
1198 	int error;
1199 
1200 	/*
1201 	 * XXX: for deleting MFC entries the information in entries
1202 	 * of size "struct mfcctl" is sufficient.
1203 	 */
1204 
1205 	mfccp = &mfcctl2;
1206 	memset(&mfcctl2, 0, sizeof(mfcctl2));
1207 
1208 	error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl));
1209 	if (error) {
1210 		/* Try with the size of mfcctl2. */
1211 		error = sockopt_get(sopt, mfccp, sizeof(struct mfcctl2));
1212 		if (error)
1213 			return error;
1214 	}
1215 
1216 	if (mrtdebug & DEBUG_MFC)
1217 		log(LOG_DEBUG, "del_mfc origin %x mcastgrp %x\n",
1218 		    ntohl(mfccp->mfcc_origin.s_addr),
1219 		    ntohl(mfccp->mfcc_mcastgrp.s_addr));
1220 
1221 	s = splsoftnet();
1222 
1223 	rt = mfc_find(&mfccp->mfcc_origin, &mfccp->mfcc_mcastgrp);
1224 	if (rt == NULL) {
1225 		splx(s);
1226 		return EADDRNOTAVAIL;
1227 	}
1228 
1229 	/*
1230 	 * free the bw_meter entries
1231 	 */
1232 	free_bw_list(rt->mfc_bw_meter);
1233 	rt->mfc_bw_meter = NULL;
1234 
1235 	LIST_REMOVE(rt, mfc_hash);
1236 	free(rt, M_MRTABLE);
1237 
1238 	splx(s);
1239 	return 0;
1240 }
1241 
1242 static int
socket_send(struct socket * s,struct mbuf * mm,struct sockaddr_in * src)1243 socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in *src)
1244 {
1245 	if (s) {
1246 		if (sbappendaddr(&s->so_rcv, sintosa(src), mm, NULL) != 0) {
1247 			sorwakeup(s);
1248 			return 0;
1249 		}
1250 		soroverflow(s);
1251 	}
1252 	m_freem(mm);
1253 	return -1;
1254 }
1255 
1256 /*
1257  * IP multicast forwarding function. This function assumes that the packet
1258  * pointed to by "ip" has arrived on (or is about to be sent to) the interface
1259  * pointed to by "ifp", and the packet is to be relayed to other networks
1260  * that have members of the packet's destination IP multicast group.
1261  *
1262  * The packet is returned unscathed to the caller, unless it is
1263  * erroneous, in which case a non-zero return value tells the caller to
1264  * discard it.
1265  */
1266 
1267 #define IP_HDR_LEN  20	/* # bytes of fixed IP header (excluding options) */
1268 #define TUNNEL_LEN  12  /* # bytes of IP option for tunnel encapsulation  */
1269 
1270 int
ip_mforward(struct mbuf * m,struct ifnet * ifp)1271 ip_mforward(struct mbuf *m, struct ifnet *ifp)
1272 {
1273 	int rc;
1274 	/*
1275 	 * save csum_flags to uphold the
1276 	 * "unscathed" guarantee.
1277 	 * ip_output() relies on that and
1278 	 * without it we send out
1279 	 * multicast packets with an invalid
1280 	 * checksum
1281 	 *
1282 	 * see PR kern/55779
1283 	 */
1284 	int csum_flags = m->m_pkthdr.csum_flags;
1285 
1286 	/*
1287 	 * Temporarily clear any in-bound checksum flags for this packet.
1288 	 */
1289 	m->m_pkthdr.csum_flags = 0;
1290 
1291 	rc = ip_mforward_real(m, ifp);
1292 
1293 	m->m_pkthdr.csum_flags = csum_flags;
1294 
1295 	return rc;
1296 }
1297 
1298 static int
ip_mforward_real(struct mbuf * m,struct ifnet * ifp)1299 ip_mforward_real(struct mbuf *m, struct ifnet *ifp)
1300 {
1301 	struct ip *ip = mtod(m, struct ip *);
1302 	struct mfc *rt;
1303 	static int srctun = 0;
1304 	struct mbuf *mm;
1305 	struct sockaddr_in sin;
1306 	int s;
1307 	vifi_t vifi;
1308 
1309 	if (mrtdebug & DEBUG_FORWARD)
1310 		log(LOG_DEBUG, "ip_mforward: src %x, dst %x, ifp %p\n",
1311 		    ntohl(ip->ip_src.s_addr), ntohl(ip->ip_dst.s_addr), ifp);
1312 
1313 	/*
1314 	 * XXX XXX: Why do we check [1] against IPOPT_LSRR? Because we
1315 	 * expect [0] to be IPOPT_NOP, maybe? In all cases that doesn't
1316 	 * make a lot of sense, a forged packet can just put two IPOPT_NOPs
1317 	 * followed by one IPOPT_LSRR, and bypass the check.
1318 	 */
1319 	if (ip->ip_hl < (IP_HDR_LEN + TUNNEL_LEN) >> 2 ||
1320 	    ((u_char *)(ip + 1))[1] != IPOPT_LSRR) {
1321 		/*
1322 		 * Packet arrived via a physical interface or
1323 		 * an encapsulated tunnel or a register_vif.
1324 		 */
1325 	} else {
1326 		/*
1327 		 * Packet arrived through a source-route tunnel.
1328 		 * Source-route tunnels are no longer supported.
1329 		 */
1330 		if ((srctun++ % 1000) == 0)
1331 			log(LOG_ERR,
1332 			    "ip_mforward: received source-routed packet from %x\n",
1333 			    ntohl(ip->ip_src.s_addr));
1334 		return EOPNOTSUPP;
1335 	}
1336 
1337 	/*
1338 	 * Don't forward a packet with time-to-live of zero or one,
1339 	 * or a packet destined to a local-only group.
1340 	 */
1341 	if (ip->ip_ttl <= 1 || IN_LOCAL_GROUP(ip->ip_dst.s_addr))
1342 		return 0;
1343 
1344 	/*
1345 	 * Determine forwarding vifs from the forwarding cache table
1346 	 */
1347 	s = splsoftnet();
1348 	++mrtstat.mrts_mfc_lookups;
1349 	rt = mfc_find(&ip->ip_src, &ip->ip_dst);
1350 
1351 	/* Entry exists, so forward if necessary */
1352 	if (rt != NULL) {
1353 		splx(s);
1354 		return ip_mdq(m, ifp, rt);
1355 	} else {
1356 		/*
1357 		 * If we don't have a route for packet's origin, make a copy
1358 		 * of the packet and send message to routing daemon.
1359 		 */
1360 
1361 		struct mbuf *mb0;
1362 		struct rtdetq *rte;
1363 		u_int32_t hash;
1364 		const int hlen = ip->ip_hl << 2;
1365 #ifdef UPCALL_TIMING
1366 		struct timeval tp;
1367 		microtime(&tp);
1368 #endif
1369 
1370 		++mrtstat.mrts_mfc_misses;
1371 
1372 		mrtstat.mrts_no_route++;
1373 		if (mrtdebug & (DEBUG_FORWARD | DEBUG_MFC))
1374 			log(LOG_DEBUG, "ip_mforward: no rte s %x g %x\n",
1375 			    ntohl(ip->ip_src.s_addr),
1376 			    ntohl(ip->ip_dst.s_addr));
1377 
1378 		/*
1379 		 * Allocate mbufs early so that we don't do extra work if we are
1380 		 * just going to fail anyway.  Make sure to pullup the header so
1381 		 * that other people can't step on it.
1382 		 */
1383 		rte = malloc(sizeof(*rte), M_MRTABLE, M_NOWAIT);
1384 		if (rte == NULL) {
1385 			splx(s);
1386 			return ENOBUFS;
1387 		}
1388 		mb0 = m_copypacket(m, M_DONTWAIT);
1389 		M_PULLUP(mb0, hlen);
1390 		if (mb0 == NULL) {
1391 			free(rte, M_MRTABLE);
1392 			splx(s);
1393 			return ENOBUFS;
1394 		}
1395 
1396 		/* is there an upcall waiting for this flow? */
1397 		hash = MFCHASH(ip->ip_src, ip->ip_dst);
1398 		LIST_FOREACH(rt, &mfchashtbl[hash], mfc_hash) {
1399 			if (in_hosteq(ip->ip_src, rt->mfc_origin) &&
1400 			    in_hosteq(ip->ip_dst, rt->mfc_mcastgrp) &&
1401 			    rt->mfc_stall != NULL)
1402 				break;
1403 		}
1404 
1405 		if (rt == NULL) {
1406 			int i;
1407 			struct igmpmsg *im;
1408 
1409 			/*
1410 			 * Locate the vifi for the incoming interface for
1411 			 * this packet.
1412 			 * If none found, drop packet.
1413 			 */
1414 			for (vifi = 0; vifi < numvifs &&
1415 				 viftable[vifi].v_ifp != ifp; vifi++)
1416 				;
1417 			if (vifi >= numvifs) /* vif not found, drop packet */
1418 				goto non_fatal;
1419 
1420 			/* no upcall, so make a new entry */
1421 			rt = malloc(sizeof(*rt), M_MRTABLE, M_NOWAIT);
1422 			if (rt == NULL)
1423 				goto fail;
1424 
1425 			/*
1426 			 * Make a copy of the header to send to the user level
1427 			 * process
1428 			 */
1429 			mm = m_copym(m, 0, hlen, M_DONTWAIT);
1430 			M_PULLUP(mm, hlen);
1431 			if (mm == NULL)
1432 				goto fail1;
1433 
1434 			/*
1435 			 * Send message to routing daemon to install
1436 			 * a route into the kernel table
1437 			 */
1438 
1439 			im = mtod(mm, struct igmpmsg *);
1440 			im->im_msgtype = IGMPMSG_NOCACHE;
1441 			im->im_mbz = 0;
1442 			im->im_vif = vifi;
1443 
1444 			mrtstat.mrts_upcalls++;
1445 
1446 			sockaddr_in_init(&sin, &ip->ip_src, 0);
1447 			if (socket_send(ip_mrouter, mm, &sin) < 0) {
1448 				log(LOG_WARNING,
1449 				    "ip_mforward: ip_mrouter socket queue full\n");
1450 				++mrtstat.mrts_upq_sockfull;
1451 			fail1:
1452 				free(rt, M_MRTABLE);
1453 			fail:
1454 				free(rte, M_MRTABLE);
1455 				m_freem(mb0);
1456 				splx(s);
1457 				return ENOBUFS;
1458 			}
1459 
1460 			/* insert new entry at head of hash chain */
1461 			rt->mfc_origin = ip->ip_src;
1462 			rt->mfc_mcastgrp = ip->ip_dst;
1463 			rt->mfc_pkt_cnt = 0;
1464 			rt->mfc_byte_cnt = 0;
1465 			rt->mfc_wrong_if = 0;
1466 			rt->mfc_expire = UPCALL_EXPIRE;
1467 			nexpire[hash]++;
1468 			for (i = 0; i < numvifs; i++) {
1469 				rt->mfc_ttls[i] = 0;
1470 				rt->mfc_flags[i] = 0;
1471 			}
1472 			rt->mfc_parent = -1;
1473 
1474 			/* clear the RP address */
1475 			rt->mfc_rp = zeroin_addr;
1476 
1477 			rt->mfc_bw_meter = NULL;
1478 
1479 			/* link into table */
1480 			LIST_INSERT_HEAD(&mfchashtbl[hash], rt, mfc_hash);
1481 			/* Add this entry to the end of the queue */
1482 			rt->mfc_stall = rte;
1483 		} else {
1484 			/* determine if q has overflowed */
1485 			struct rtdetq **p;
1486 			int npkts = 0;
1487 
1488 			/*
1489 			 * XXX ouch! we need to append to the list, but we
1490 			 * only have a pointer to the front, so we have to
1491 			 * scan the entire list every time.
1492 			 */
1493 			for (p = &rt->mfc_stall; *p != NULL; p = &(*p)->next)
1494 				if (++npkts > MAX_UPQ) {
1495 					mrtstat.mrts_upq_ovflw++;
1496 				non_fatal:
1497 					free(rte, M_MRTABLE);
1498 					m_freem(mb0);
1499 					splx(s);
1500 					return 0;
1501 				}
1502 
1503 			/* Add this entry to the end of the queue */
1504 			*p = rte;
1505 		}
1506 
1507 		rte->next = NULL;
1508 		rte->m = mb0;
1509 		rte->ifp = ifp;
1510 #ifdef UPCALL_TIMING
1511 		rte->t = tp;
1512 #endif
1513 
1514 		splx(s);
1515 
1516 		return 0;
1517 	}
1518 }
1519 
1520 /*ARGSUSED*/
1521 static void
expire_upcalls(void * v)1522 expire_upcalls(void *v)
1523 {
1524 	int i;
1525 
1526 	/* XXX NOMPSAFE still need softnet_lock */
1527 	mutex_enter(softnet_lock);
1528 	KERNEL_LOCK(1, NULL);
1529 
1530 	for (i = 0; i < MFCTBLSIZ; i++) {
1531 		struct mfc *rt, *nrt;
1532 
1533 		if (nexpire[i] == 0)
1534 			continue;
1535 
1536 		for (rt = LIST_FIRST(&mfchashtbl[i]); rt; rt = nrt) {
1537 			nrt = LIST_NEXT(rt, mfc_hash);
1538 
1539 			if (rt->mfc_expire == 0 || --rt->mfc_expire > 0)
1540 				continue;
1541 			nexpire[i]--;
1542 
1543 			/*
1544 			 * free the bw_meter entries
1545 			 */
1546 			while (rt->mfc_bw_meter != NULL) {
1547 				struct bw_meter *x = rt->mfc_bw_meter;
1548 
1549 				rt->mfc_bw_meter = x->bm_mfc_next;
1550 				kmem_intr_free(x, sizeof(*x));
1551 			}
1552 
1553 			++mrtstat.mrts_cache_cleanups;
1554 			if (mrtdebug & DEBUG_EXPIRE)
1555 				log(LOG_DEBUG,
1556 				    "expire_upcalls: expiring (%x %x)\n",
1557 				    ntohl(rt->mfc_origin.s_addr),
1558 				    ntohl(rt->mfc_mcastgrp.s_addr));
1559 
1560 			expire_mfc(rt);
1561 		}
1562 	}
1563 
1564 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
1565 	    expire_upcalls, NULL);
1566 
1567 	KERNEL_UNLOCK_ONE(NULL);
1568 	mutex_exit(softnet_lock);
1569 }
1570 
1571 /*
1572  * Macro to send packet on vif.
1573  */
1574 #define MC_SEND(ip, vifp, m) do {					\
1575 	if ((vifp)->v_flags & VIFF_TUNNEL)				\
1576 		encap_send((ip), (vifp), (m));				\
1577 	else								\
1578 		phyint_send((ip), (vifp), (m));				\
1579 } while (/*CONSTCOND*/ 0)
1580 
1581 /*
1582  * Packet forwarding routine once entry in the cache is made
1583  */
1584 static int
ip_mdq(struct mbuf * m,struct ifnet * ifp,struct mfc * rt)1585 ip_mdq(struct mbuf *m, struct ifnet *ifp, struct mfc *rt)
1586 {
1587 	struct ip *ip = mtod(m, struct ip *);
1588 	vifi_t vifi;
1589 	struct vif *vifp;
1590 	struct sockaddr_in sin;
1591 	const int plen = ntohs(ip->ip_len) - (ip->ip_hl << 2);
1592 
1593 	/*
1594 	 * Don't forward if it didn't arrive from the parent vif for its origin.
1595 	 */
1596 	vifi = rt->mfc_parent;
1597 	if ((vifi >= numvifs) || (viftable[vifi].v_ifp != ifp)) {
1598 		/* came in the wrong interface */
1599 		if (mrtdebug & DEBUG_FORWARD)
1600 			log(LOG_DEBUG, "wrong if: ifp %p vifi %d vififp %p\n",
1601 			    ifp, vifi,
1602 			    vifi >= numvifs ? 0 : viftable[vifi].v_ifp);
1603 		++mrtstat.mrts_wrong_if;
1604 		++rt->mfc_wrong_if;
1605 
1606 		/*
1607 		 * If we are doing PIM assert processing, send a message
1608 		 * to the routing daemon.
1609 		 *
1610 		 * XXX: A PIM-SM router needs the WRONGVIF detection so it
1611 		 * can complete the SPT switch, regardless of the type
1612 		 * of the iif (broadcast media, GRE tunnel, etc).
1613 		 */
1614 		if (pim_assert && (vifi < numvifs) && viftable[vifi].v_ifp) {
1615 			struct timeval now;
1616 			u_int32_t delta;
1617 
1618 #ifdef PIM
1619 			if (ifp == &multicast_register_if)
1620 				pimstat.pims_rcv_registers_wrongiif++;
1621 #endif
1622 
1623 			/* Get vifi for the incoming packet */
1624 			for (vifi = 0;
1625 			     vifi < numvifs && viftable[vifi].v_ifp != ifp;
1626 			     vifi++)
1627 			    ;
1628 			if (vifi >= numvifs) {
1629 				/* The iif is not found: ignore the packet. */
1630 				return 0;
1631 			}
1632 
1633 			if (rt->mfc_flags[vifi] &
1634 			    MRT_MFC_FLAGS_DISABLE_WRONGVIF) {
1635 				/* WRONGVIF disabled: ignore the packet */
1636 				return 0;
1637 			}
1638 
1639 			microtime(&now);
1640 
1641 			TV_DELTA(rt->mfc_last_assert, now, delta);
1642 
1643 			if (delta > ASSERT_MSG_TIME) {
1644 				struct igmpmsg *im;
1645 				const int hlen = ip->ip_hl << 2;
1646 				struct mbuf *mm =
1647 				    m_copym(m, 0, hlen, M_DONTWAIT);
1648 
1649 				M_PULLUP(mm, hlen);
1650 				if (mm == NULL)
1651 					return ENOBUFS;
1652 
1653 				rt->mfc_last_assert = now;
1654 
1655 				im = mtod(mm, struct igmpmsg *);
1656 				im->im_msgtype	= IGMPMSG_WRONGVIF;
1657 				im->im_mbz	= 0;
1658 				im->im_vif	= vifi;
1659 
1660 				mrtstat.mrts_upcalls++;
1661 
1662 				sockaddr_in_init(&sin, &im->im_src, 0);
1663 				if (socket_send(ip_mrouter, mm, &sin) < 0) {
1664 					log(LOG_WARNING,
1665 					    "ip_mforward: ip_mrouter socket queue full\n");
1666 					++mrtstat.mrts_upq_sockfull;
1667 					return ENOBUFS;
1668 				}
1669 			}
1670 		}
1671 		return 0;
1672 	}
1673 
1674 	/* If I sourced this packet, it counts as output, else it was input. */
1675 	if (in_hosteq(ip->ip_src, viftable[vifi].v_lcl_addr)) {
1676 		viftable[vifi].v_pkt_out++;
1677 		viftable[vifi].v_bytes_out += plen;
1678 	} else {
1679 		viftable[vifi].v_pkt_in++;
1680 		viftable[vifi].v_bytes_in += plen;
1681 	}
1682 	rt->mfc_pkt_cnt++;
1683 	rt->mfc_byte_cnt += plen;
1684 
1685 	/*
1686 	 * For each vif, decide if a copy of the packet should be forwarded.
1687 	 * Forward if:
1688 	 *  - the ttl exceeds the vif's threshold
1689 	 *  - there are group members downstream on interface
1690 	 */
1691 	for (vifp = viftable, vifi = 0; vifi < numvifs; vifp++, vifi++) {
1692 		if ((rt->mfc_ttls[vifi] > 0) &&
1693 			(ip->ip_ttl > rt->mfc_ttls[vifi])) {
1694 			vifp->v_pkt_out++;
1695 			vifp->v_bytes_out += plen;
1696 #ifdef PIM
1697 			if (vifp->v_flags & VIFF_REGISTER)
1698 				pim_register_send(ip, vifp, m, rt);
1699 			else
1700 #endif
1701 			MC_SEND(ip, vifp, m);
1702 		}
1703 	}
1704 
1705 	/*
1706 	 * Perform upcall-related bw measuring.
1707 	 */
1708 	if (rt->mfc_bw_meter != NULL) {
1709 		struct bw_meter *x;
1710 		struct timeval now;
1711 
1712 		microtime(&now);
1713 		for (x = rt->mfc_bw_meter; x != NULL; x = x->bm_mfc_next)
1714 			bw_meter_receive_packet(x, plen, &now);
1715 	}
1716 
1717 	return 0;
1718 }
1719 
1720 static void
phyint_send(struct ip * ip,struct vif * vifp,struct mbuf * m)1721 phyint_send(struct ip *ip, struct vif *vifp, struct mbuf *m)
1722 {
1723 	struct mbuf *mb_copy;
1724 	const int hlen = ip->ip_hl << 2;
1725 
1726 	/*
1727 	 * Make a new reference to the packet; make sure that
1728 	 * the IP header is actually copied, not just referenced,
1729 	 * so that ip_output() only scribbles on the copy.
1730 	 */
1731 	mb_copy = m_copypacket(m, M_DONTWAIT);
1732 	M_PULLUP(mb_copy, hlen);
1733 	if (mb_copy == NULL)
1734 		return;
1735 
1736 	if (vifp->v_rate_limit <= 0)
1737 		tbf_send_packet(vifp, mb_copy);
1738 	else
1739 		tbf_control(vifp, mb_copy, mtod(mb_copy, struct ip *),
1740 		    ntohs(ip->ip_len));
1741 }
1742 
1743 static void
encap_send(struct ip * ip,struct vif * vifp,struct mbuf * m)1744 encap_send(struct ip *ip, struct vif *vifp, struct mbuf *m)
1745 {
1746 	struct mbuf *mb_copy;
1747 	struct ip *ip_copy;
1748 	int i, len = ntohs(ip->ip_len) + sizeof(multicast_encap_iphdr);
1749 
1750 	/* Take care of delayed checksums */
1751 	if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
1752 		in_undefer_cksum_tcpudp(m);
1753 		m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4);
1754 	}
1755 
1756 	/*
1757 	 * copy the old packet & pullup its IP header into the
1758 	 * new mbuf so we can modify it.  Try to fill the new
1759 	 * mbuf since if we don't the ethernet driver will.
1760 	 */
1761 	MGETHDR(mb_copy, M_DONTWAIT, MT_DATA);
1762 	if (mb_copy == NULL)
1763 		return;
1764 	mb_copy->m_data += max_linkhdr;
1765 	mb_copy->m_pkthdr.len = len;
1766 	mb_copy->m_len = sizeof(multicast_encap_iphdr);
1767 
1768 	if ((mb_copy->m_next = m_copypacket(m, M_DONTWAIT)) == NULL) {
1769 		m_freem(mb_copy);
1770 		return;
1771 	}
1772 	i = MHLEN - max_linkhdr;
1773 	if (i > len)
1774 		i = len;
1775 	mb_copy = m_pullup(mb_copy, i);
1776 	if (mb_copy == NULL)
1777 		return;
1778 
1779 	/*
1780 	 * fill in the encapsulating IP header.
1781 	 */
1782 	ip_copy = mtod(mb_copy, struct ip *);
1783 	*ip_copy = multicast_encap_iphdr;
1784 	if (len < IP_MINFRAGSIZE)
1785 		ip_copy->ip_id = 0;
1786 	else
1787 		ip_copy->ip_id = ip_newid(NULL);
1788 	ip_copy->ip_len = htons(len);
1789 	ip_copy->ip_src = vifp->v_lcl_addr;
1790 	ip_copy->ip_dst = vifp->v_rmt_addr;
1791 
1792 	/*
1793 	 * turn the encapsulated IP header back into a valid one.
1794 	 */
1795 	ip = (struct ip *)((char *)ip_copy + sizeof(multicast_encap_iphdr));
1796 	--ip->ip_ttl;
1797 	ip->ip_sum = 0;
1798 	mb_copy->m_data += sizeof(multicast_encap_iphdr);
1799 	ip->ip_sum = in_cksum(mb_copy, ip->ip_hl << 2);
1800 	mb_copy->m_data -= sizeof(multicast_encap_iphdr);
1801 
1802 	if (vifp->v_rate_limit <= 0)
1803 		tbf_send_packet(vifp, mb_copy);
1804 	else
1805 		tbf_control(vifp, mb_copy, ip, ntohs(ip_copy->ip_len));
1806 }
1807 
1808 /*
1809  * De-encapsulate a packet and feed it back through ip input.
1810  */
1811 static void
vif_input(struct mbuf * m,int off,int proto,void * eparg)1812 vif_input(struct mbuf *m, int off, int proto, void *eparg)
1813 {
1814 	struct vif *vifp = eparg;
1815 
1816 	KASSERT(vifp != NULL);
1817 
1818 	if (proto != ENCAP_PROTO) {
1819 		m_freem(m);
1820 		mrtstat.mrts_bad_tunnel++;
1821 		return;
1822 	}
1823 
1824 	m_adj(m, off);
1825 	m_set_rcvif(m, vifp->v_ifp);
1826 
1827 	if (__predict_false(!pktq_enqueue(ip_pktq, m, 0))) {
1828 		m_freem(m);
1829 	}
1830 }
1831 
1832 /*
1833  * Check if the packet should be received on the vif denoted by arg.
1834  * (The encap selection code will call this once per vif since each is
1835  * registered separately.)
1836  */
1837 static int
vif_encapcheck(struct mbuf * m,int off,int proto,void * arg)1838 vif_encapcheck(struct mbuf *m, int off, int proto, void *arg)
1839 {
1840 	struct vif *vifp;
1841 	struct ip ip;
1842 
1843 #ifdef DIAGNOSTIC
1844 	if (!arg || proto != IPPROTO_IPV4)
1845 		panic("unexpected arg in vif_encapcheck");
1846 #endif
1847 
1848 	/*
1849 	 * Accept the packet only if the inner header is multicast
1850 	 * and the outer header matches a tunnel-mode vif.  Order
1851 	 * checks in the hope that common non-matching packets will be
1852 	 * rejected quickly.  Assume that unicast IPv4 traffic in a
1853 	 * parallel tunnel (e.g. gif(4)) is unlikely.
1854 	 */
1855 
1856 	/* Obtain the outer IP header and the vif pointer. */
1857 	m_copydata(m, 0, sizeof(ip), (void *)&ip);
1858 	vifp = (struct vif *)arg;
1859 
1860 	/*
1861 	 * The outer source must match the vif's remote peer address.
1862 	 * For a multicast router with several tunnels, this is the
1863 	 * only check that will fail on packets in other tunnels,
1864 	 * assuming the local address is the same.
1865 	 */
1866 	if (!in_hosteq(vifp->v_rmt_addr, ip.ip_src))
1867 		return 0;
1868 
1869 	/* The outer destination must match the vif's local address. */
1870 	if (!in_hosteq(vifp->v_lcl_addr, ip.ip_dst))
1871 		return 0;
1872 
1873 	/* The vif must be of tunnel type. */
1874 	if ((vifp->v_flags & VIFF_TUNNEL) == 0)
1875 		return 0;
1876 
1877 	/* Check that the inner destination is multicast. */
1878 	if (off + sizeof(ip) > m->m_pkthdr.len)
1879 		return 0;
1880 	m_copydata(m, off, sizeof(ip), (void *)&ip);
1881 	if (!IN_MULTICAST(ip.ip_dst.s_addr))
1882 		return 0;
1883 
1884 	/*
1885 	 * We have checked that both the outer src and dst addresses
1886 	 * match the vif, and that the inner destination is multicast
1887 	 * (224/5).  By claiming more than 64, we intend to
1888 	 * preferentially take packets that also match a parallel
1889 	 * gif(4).
1890 	 */
1891 	return 32 + 32 + 5;
1892 }
1893 
1894 /*
1895  * Token bucket filter module
1896  */
1897 static void
tbf_control(struct vif * vifp,struct mbuf * m,struct ip * ip,u_int32_t len)1898 tbf_control(struct vif *vifp, struct mbuf *m, struct ip *ip, u_int32_t len)
1899 {
1900 
1901 	if (len > MAX_BKT_SIZE) {
1902 		/* drop if packet is too large */
1903 		mrtstat.mrts_pkt2large++;
1904 		m_freem(m);
1905 		return;
1906 	}
1907 
1908 	tbf_update_tokens(vifp);
1909 
1910 	/*
1911 	 * If there are enough tokens, and the queue is empty, send this packet
1912 	 * out immediately.  Otherwise, try to insert it on this vif's queue.
1913 	 */
1914 	if (vifp->tbf_q_len == 0) {
1915 		if (len <= vifp->tbf_n_tok) {
1916 			vifp->tbf_n_tok -= len;
1917 			tbf_send_packet(vifp, m);
1918 		} else {
1919 			/* queue packet and timeout till later */
1920 			tbf_queue(vifp, m);
1921 			callout_reset(&vifp->v_repq_ch, TBF_REPROCESS,
1922 			    tbf_reprocess_q, vifp);
1923 		}
1924 	} else {
1925 		if (vifp->tbf_q_len >= vifp->tbf_max_q_len &&
1926 		    !tbf_dq_sel(vifp, ip)) {
1927 			/* queue full, and couldn't make room */
1928 			mrtstat.mrts_q_overflow++;
1929 			m_freem(m);
1930 		} else {
1931 			/* queue length low enough, or made room */
1932 			tbf_queue(vifp, m);
1933 			tbf_process_q(vifp);
1934 		}
1935 	}
1936 }
1937 
1938 /*
1939  * adds a packet to the queue at the interface
1940  */
1941 static void
tbf_queue(struct vif * vifp,struct mbuf * m)1942 tbf_queue(struct vif *vifp, struct mbuf *m)
1943 {
1944 	int s = splsoftnet();
1945 
1946 	/* insert at tail */
1947 	*vifp->tbf_t = m;
1948 	vifp->tbf_t = &m->m_nextpkt;
1949 	vifp->tbf_q_len++;
1950 
1951 	splx(s);
1952 }
1953 
1954 /*
1955  * processes the queue at the interface
1956  */
1957 static void
tbf_process_q(struct vif * vifp)1958 tbf_process_q(struct vif *vifp)
1959 {
1960 	struct mbuf *m;
1961 	int len;
1962 	int s = splsoftnet();
1963 
1964 	/*
1965 	 * Loop through the queue at the interface and send as many packets
1966 	 * as possible.
1967 	 */
1968 	for (m = vifp->tbf_q; m != NULL; m = vifp->tbf_q) {
1969 		len = ntohs(mtod(m, struct ip *)->ip_len);
1970 
1971 		/* determine if the packet can be sent */
1972 		if (len <= vifp->tbf_n_tok) {
1973 			/* if so,
1974 			 * reduce no of tokens, dequeue the packet,
1975 			 * send the packet.
1976 			 */
1977 			if ((vifp->tbf_q = m->m_nextpkt) == NULL)
1978 				vifp->tbf_t = &vifp->tbf_q;
1979 			--vifp->tbf_q_len;
1980 
1981 			m->m_nextpkt = NULL;
1982 			vifp->tbf_n_tok -= len;
1983 			tbf_send_packet(vifp, m);
1984 		} else
1985 			break;
1986 	}
1987 	splx(s);
1988 }
1989 
1990 static void
tbf_reprocess_q(void * arg)1991 tbf_reprocess_q(void *arg)
1992 {
1993 	struct vif *vifp = arg;
1994 
1995 	if (ip_mrouter == NULL)
1996 		return;
1997 
1998 	tbf_update_tokens(vifp);
1999 	tbf_process_q(vifp);
2000 
2001 	if (vifp->tbf_q_len != 0)
2002 		callout_reset(&vifp->v_repq_ch, TBF_REPROCESS,
2003 		    tbf_reprocess_q, vifp);
2004 }
2005 
2006 /* function that will selectively discard a member of the queue
2007  * based on the precedence value and the priority
2008  */
2009 static int
tbf_dq_sel(struct vif * vifp,struct ip * ip)2010 tbf_dq_sel(struct vif *vifp, struct ip *ip)
2011 {
2012 	u_int p;
2013 	struct mbuf **mp, *m;
2014 	int s = splsoftnet();
2015 
2016 	p = priority(vifp, ip);
2017 
2018 	for (mp = &vifp->tbf_q, m = *mp;
2019 	    m != NULL;
2020 	    mp = &m->m_nextpkt, m = *mp) {
2021 		if (p > priority(vifp, mtod(m, struct ip *))) {
2022 			if ((*mp = m->m_nextpkt) == NULL)
2023 				vifp->tbf_t = mp;
2024 			--vifp->tbf_q_len;
2025 
2026 			m_freem(m);
2027 			mrtstat.mrts_drop_sel++;
2028 			splx(s);
2029 			return 1;
2030 		}
2031 	}
2032 	splx(s);
2033 	return 0;
2034 }
2035 
2036 static void
tbf_send_packet(struct vif * vifp,struct mbuf * m)2037 tbf_send_packet(struct vif *vifp, struct mbuf *m)
2038 {
2039 	int error;
2040 	int s = splsoftnet();
2041 
2042 	if (vifp->v_flags & VIFF_TUNNEL) {
2043 		/* If tunnel options */
2044 		ip_output(m, NULL, &vifp->v_route, IP_FORWARDING, NULL, NULL);
2045 	} else {
2046 		/* if physical interface option, extract the options and then send */
2047 		struct ip_moptions imo;
2048 
2049 		imo.imo_multicast_if_index = if_get_index(vifp->v_ifp);
2050 		imo.imo_multicast_ttl = mtod(m, struct ip *)->ip_ttl - 1;
2051 		imo.imo_multicast_loop = 1;
2052 
2053 		error = ip_output(m, NULL, NULL, IP_FORWARDING|IP_MULTICASTOPTS,
2054 		    &imo, NULL);
2055 
2056 		if (mrtdebug & DEBUG_XMIT)
2057 			log(LOG_DEBUG, "phyint_send on vif %ld err %d\n",
2058 			    (long)(vifp - viftable), error);
2059 	}
2060 	splx(s);
2061 }
2062 
2063 /* determine the current time and then
2064  * the elapsed time (between the last time and time now)
2065  * in milliseconds & update the no. of tokens in the bucket
2066  */
2067 static void
tbf_update_tokens(struct vif * vifp)2068 tbf_update_tokens(struct vif *vifp)
2069 {
2070 	struct timeval tp;
2071 	u_int32_t tm;
2072 	int s = splsoftnet();
2073 
2074 	microtime(&tp);
2075 
2076 	TV_DELTA(tp, vifp->tbf_last_pkt_t, tm);
2077 
2078 	/*
2079 	 * This formula is actually
2080 	 * "time in seconds" * "bytes/second".
2081 	 *
2082 	 * (tm / 1000000) * (v_rate_limit * 1000 * (1000/1024) / 8)
2083 	 *
2084 	 * The (1000/1024) was introduced in add_vif to optimize
2085 	 * this divide into a shift.
2086 	 */
2087 	vifp->tbf_n_tok += tm * vifp->v_rate_limit / 8192;
2088 	vifp->tbf_last_pkt_t = tp;
2089 
2090 	if (vifp->tbf_n_tok > MAX_BKT_SIZE)
2091 		vifp->tbf_n_tok = MAX_BKT_SIZE;
2092 
2093 	splx(s);
2094 }
2095 
2096 static int
priority(struct vif * vifp,struct ip * ip)2097 priority(struct vif *vifp, struct ip *ip)
2098 {
2099 	int prio = 50;	/* the lowest priority -- default case */
2100 
2101 	/* temporary hack; may add general packet classifier some day */
2102 
2103 	/*
2104 	 * XXX XXX: We're reading the UDP header, but we didn't ensure
2105 	 * it was present in the packet.
2106 	 */
2107 
2108 	/*
2109 	 * The UDP port space is divided up into four priority ranges:
2110 	 * [0, 16384)     : unclassified - lowest priority
2111 	 * [16384, 32768) : audio - highest priority
2112 	 * [32768, 49152) : whiteboard - medium priority
2113 	 * [49152, 65536) : video - low priority
2114 	 */
2115 	if (ip->ip_p == IPPROTO_UDP) {
2116 		struct udphdr *udp = (struct udphdr *)(((char *)ip) + (ip->ip_hl << 2));
2117 
2118 		switch (ntohs(udp->uh_dport) & 0xc000) {
2119 		case 0x4000:
2120 			prio = 70;
2121 			break;
2122 		case 0x8000:
2123 			prio = 60;
2124 			break;
2125 		case 0xc000:
2126 			prio = 55;
2127 			break;
2128 		}
2129 
2130 		if (tbfdebug > 1)
2131 			log(LOG_DEBUG, "port %x prio %d\n",
2132 			    ntohs(udp->uh_dport), prio);
2133 	}
2134 
2135 	return prio;
2136 }
2137 
2138 /*
2139  * Code for bandwidth monitors
2140  */
2141 
2142 /*
2143  * Define common interface for timeval-related methods
2144  */
2145 #define	BW_TIMEVALCMP(tvp, uvp, cmp) timercmp((tvp), (uvp), cmp)
2146 #define	BW_TIMEVALDECR(vvp, uvp) timersub((vvp), (uvp), (vvp))
2147 #define	BW_TIMEVALADD(vvp, uvp) timeradd((vvp), (uvp), (vvp))
2148 
2149 static uint32_t
compute_bw_meter_flags(struct bw_upcall * req)2150 compute_bw_meter_flags(struct bw_upcall *req)
2151 {
2152 	uint32_t flags = 0;
2153 
2154 	if (req->bu_flags & BW_UPCALL_UNIT_PACKETS)
2155 		flags |= BW_METER_UNIT_PACKETS;
2156 	if (req->bu_flags & BW_UPCALL_UNIT_BYTES)
2157 		flags |= BW_METER_UNIT_BYTES;
2158 	if (req->bu_flags & BW_UPCALL_GEQ)
2159 		flags |= BW_METER_GEQ;
2160 	if (req->bu_flags & BW_UPCALL_LEQ)
2161 		flags |= BW_METER_LEQ;
2162 
2163 	return flags;
2164 }
2165 
2166 /*
2167  * Add a bw_meter entry
2168  */
2169 static int
add_bw_upcall(struct bw_upcall * req)2170 add_bw_upcall(struct bw_upcall *req)
2171 {
2172 	int s;
2173 	struct mfc *mfc;
2174 	struct timeval delta = { BW_UPCALL_THRESHOLD_INTERVAL_MIN_SEC,
2175 		BW_UPCALL_THRESHOLD_INTERVAL_MIN_USEC };
2176 	struct timeval now;
2177 	struct bw_meter *x;
2178 	uint32_t flags;
2179 
2180 	if (!(mrt_api_config & MRT_MFC_BW_UPCALL))
2181 		return EOPNOTSUPP;
2182 
2183 	/* Test if the flags are valid */
2184 	if (!(req->bu_flags & (BW_UPCALL_UNIT_PACKETS | BW_UPCALL_UNIT_BYTES)))
2185 		return EINVAL;
2186 	if (!(req->bu_flags & (BW_UPCALL_GEQ | BW_UPCALL_LEQ)))
2187 		return EINVAL;
2188 	if ((req->bu_flags & (BW_UPCALL_GEQ | BW_UPCALL_LEQ))
2189 	    == (BW_UPCALL_GEQ | BW_UPCALL_LEQ))
2190 		return EINVAL;
2191 
2192 	/* Test if the threshold time interval is valid */
2193 	if (BW_TIMEVALCMP(&req->bu_threshold.b_time, &delta, <))
2194 		return EINVAL;
2195 
2196 	flags = compute_bw_meter_flags(req);
2197 
2198 	/*
2199 	 * Find if we have already same bw_meter entry
2200 	 */
2201 	s = splsoftnet();
2202 	mfc = mfc_find(&req->bu_src, &req->bu_dst);
2203 	if (mfc == NULL) {
2204 		splx(s);
2205 		return EADDRNOTAVAIL;
2206 	}
2207 	for (x = mfc->mfc_bw_meter; x != NULL; x = x->bm_mfc_next) {
2208 		if ((BW_TIMEVALCMP(&x->bm_threshold.b_time,
2209 		    &req->bu_threshold.b_time, ==)) &&
2210 		    (x->bm_threshold.b_packets == req->bu_threshold.b_packets) &&
2211 		    (x->bm_threshold.b_bytes == req->bu_threshold.b_bytes) &&
2212 		    (x->bm_flags & BW_METER_USER_FLAGS) == flags)  {
2213 			splx(s);
2214 			return 0;		/* XXX Already installed */
2215 		}
2216 	}
2217 
2218 	/* Allocate the new bw_meter entry */
2219 	x = kmem_intr_alloc(sizeof(*x), KM_NOSLEEP);
2220 	if (x == NULL) {
2221 		splx(s);
2222 		return ENOBUFS;
2223 	}
2224 
2225 	/* Set the new bw_meter entry */
2226 	x->bm_threshold.b_time = req->bu_threshold.b_time;
2227 	microtime(&now);
2228 	x->bm_start_time = now;
2229 	x->bm_threshold.b_packets = req->bu_threshold.b_packets;
2230 	x->bm_threshold.b_bytes = req->bu_threshold.b_bytes;
2231 	x->bm_measured.b_packets = 0;
2232 	x->bm_measured.b_bytes = 0;
2233 	x->bm_flags = flags;
2234 	x->bm_time_next = NULL;
2235 	x->bm_time_hash = BW_METER_BUCKETS;
2236 
2237 	/* Add the new bw_meter entry to the front of entries for this MFC */
2238 	x->bm_mfc = mfc;
2239 	x->bm_mfc_next = mfc->mfc_bw_meter;
2240 	mfc->mfc_bw_meter = x;
2241 	schedule_bw_meter(x, &now);
2242 	splx(s);
2243 
2244 	return 0;
2245 }
2246 
2247 static void
free_bw_list(struct bw_meter * list)2248 free_bw_list(struct bw_meter *list)
2249 {
2250 	while (list != NULL) {
2251 		struct bw_meter *x = list;
2252 
2253 		list = list->bm_mfc_next;
2254 		unschedule_bw_meter(x);
2255 		kmem_intr_free(x, sizeof(*x));
2256 	}
2257 }
2258 
2259 /*
2260  * Delete one or multiple bw_meter entries
2261  */
2262 static int
del_bw_upcall(struct bw_upcall * req)2263 del_bw_upcall(struct bw_upcall *req)
2264 {
2265 	int s;
2266 	struct mfc *mfc;
2267 	struct bw_meter *x;
2268 
2269 	if (!(mrt_api_config & MRT_MFC_BW_UPCALL))
2270 		return EOPNOTSUPP;
2271 
2272 	s = splsoftnet();
2273 	/* Find the corresponding MFC entry */
2274 	mfc = mfc_find(&req->bu_src, &req->bu_dst);
2275 	if (mfc == NULL) {
2276 		splx(s);
2277 		return EADDRNOTAVAIL;
2278 	} else if (req->bu_flags & BW_UPCALL_DELETE_ALL) {
2279 		/*
2280 		 * Delete all bw_meter entries for this mfc
2281 		 */
2282 		struct bw_meter *list;
2283 
2284 		list = mfc->mfc_bw_meter;
2285 		mfc->mfc_bw_meter = NULL;
2286 		free_bw_list(list);
2287 		splx(s);
2288 		return 0;
2289 	} else {			/* Delete a single bw_meter entry */
2290 		struct bw_meter *prev;
2291 		uint32_t flags = 0;
2292 
2293 		flags = compute_bw_meter_flags(req);
2294 
2295 		/* Find the bw_meter entry to delete */
2296 		for (prev = NULL, x = mfc->mfc_bw_meter; x != NULL;
2297 		     prev = x, x = x->bm_mfc_next) {
2298 			if ((BW_TIMEVALCMP(&x->bm_threshold.b_time,
2299 			    &req->bu_threshold.b_time, ==)) &&
2300 			    (x->bm_threshold.b_packets == req->bu_threshold.b_packets) &&
2301 			    (x->bm_threshold.b_bytes == req->bu_threshold.b_bytes) &&
2302 			    (x->bm_flags & BW_METER_USER_FLAGS) == flags)
2303 				break;
2304 		}
2305 		if (x != NULL) { /* Delete entry from the list for this MFC */
2306 			if (prev != NULL)
2307 				prev->bm_mfc_next = x->bm_mfc_next;	/* remove from middle*/
2308 			else
2309 				x->bm_mfc->mfc_bw_meter = x->bm_mfc_next;/* new head of list */
2310 
2311 			unschedule_bw_meter(x);
2312 			splx(s);
2313 			/* Free the bw_meter entry */
2314 			kmem_intr_free(x, sizeof(*x));
2315 			return 0;
2316 		} else {
2317 			splx(s);
2318 			return EINVAL;
2319 		}
2320 	}
2321 	/* NOTREACHED */
2322 }
2323 
2324 /*
2325  * Perform bandwidth measurement processing that may result in an upcall
2326  */
2327 static void
bw_meter_receive_packet(struct bw_meter * x,int plen,struct timeval * nowp)2328 bw_meter_receive_packet(struct bw_meter *x, int plen, struct timeval *nowp)
2329 {
2330 	struct timeval delta;
2331 
2332 	delta = *nowp;
2333 	BW_TIMEVALDECR(&delta, &x->bm_start_time);
2334 
2335 	if (x->bm_flags & BW_METER_GEQ) {
2336 		/*
2337 		 * Processing for ">=" type of bw_meter entry
2338 		 */
2339 		if (BW_TIMEVALCMP(&delta, &x->bm_threshold.b_time, >)) {
2340 			/* Reset the bw_meter entry */
2341 			x->bm_start_time = *nowp;
2342 			x->bm_measured.b_packets = 0;
2343 			x->bm_measured.b_bytes = 0;
2344 			x->bm_flags &= ~BW_METER_UPCALL_DELIVERED;
2345 		}
2346 
2347 		/* Record that a packet is received */
2348 		x->bm_measured.b_packets++;
2349 		x->bm_measured.b_bytes += plen;
2350 
2351 		/*
2352 		 * Test if we should deliver an upcall
2353 		 */
2354 		if (!(x->bm_flags & BW_METER_UPCALL_DELIVERED)) {
2355 			if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
2356 				 (x->bm_measured.b_packets >= x->bm_threshold.b_packets)) ||
2357 				((x->bm_flags & BW_METER_UNIT_BYTES) &&
2358 				 (x->bm_measured.b_bytes >= x->bm_threshold.b_bytes))) {
2359 				/* Prepare an upcall for delivery */
2360 				bw_meter_prepare_upcall(x, nowp);
2361 				x->bm_flags |= BW_METER_UPCALL_DELIVERED;
2362 			}
2363 		}
2364 	} else if (x->bm_flags & BW_METER_LEQ) {
2365 		/*
2366 		 * Processing for "<=" type of bw_meter entry
2367 		 */
2368 		if (BW_TIMEVALCMP(&delta, &x->bm_threshold.b_time, >)) {
2369 			/*
2370 			 * We are behind time with the multicast forwarding table
2371 			 * scanning for "<=" type of bw_meter entries, so test now
2372 			 * if we should deliver an upcall.
2373 			 */
2374 			if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
2375 				 (x->bm_measured.b_packets <= x->bm_threshold.b_packets)) ||
2376 				((x->bm_flags & BW_METER_UNIT_BYTES) &&
2377 				 (x->bm_measured.b_bytes <= x->bm_threshold.b_bytes))) {
2378 				/* Prepare an upcall for delivery */
2379 				bw_meter_prepare_upcall(x, nowp);
2380 			}
2381 			/* Reschedule the bw_meter entry */
2382 			unschedule_bw_meter(x);
2383 			schedule_bw_meter(x, nowp);
2384 		}
2385 
2386 		/* Record that a packet is received */
2387 		x->bm_measured.b_packets++;
2388 		x->bm_measured.b_bytes += plen;
2389 
2390 		/*
2391 		 * Test if we should restart the measuring interval
2392 		 */
2393 		if ((x->bm_flags & BW_METER_UNIT_PACKETS &&
2394 		     x->bm_measured.b_packets <= x->bm_threshold.b_packets) ||
2395 		    (x->bm_flags & BW_METER_UNIT_BYTES &&
2396 		     x->bm_measured.b_bytes <= x->bm_threshold.b_bytes)) {
2397 			/* Don't restart the measuring interval */
2398 		} else {
2399 			/* Do restart the measuring interval */
2400 			/*
2401 			 * XXX: note that we don't unschedule and schedule, because this
2402 			 * might be too much overhead per packet. Instead, when we process
2403 			 * all entries for a given timer hash bin, we check whether it is
2404 			 * really a timeout. If not, we reschedule at that time.
2405 			 */
2406 			x->bm_start_time = *nowp;
2407 			x->bm_measured.b_packets = 0;
2408 			x->bm_measured.b_bytes = 0;
2409 			x->bm_flags &= ~BW_METER_UPCALL_DELIVERED;
2410 		}
2411 	}
2412 }
2413 
2414 /*
2415  * Prepare a bandwidth-related upcall
2416  */
2417 static void
bw_meter_prepare_upcall(struct bw_meter * x,struct timeval * nowp)2418 bw_meter_prepare_upcall(struct bw_meter *x, struct timeval *nowp)
2419 {
2420 	struct timeval delta;
2421 	struct bw_upcall *u;
2422 
2423 	/*
2424 	 * Compute the measured time interval
2425 	 */
2426 	delta = *nowp;
2427 	BW_TIMEVALDECR(&delta, &x->bm_start_time);
2428 
2429 	/*
2430 	 * If there are too many pending upcalls, deliver them now
2431 	 */
2432 	if (bw_upcalls_n >= BW_UPCALLS_MAX)
2433 		bw_upcalls_send();
2434 
2435 	/*
2436 	 * Set the bw_upcall entry
2437 	 */
2438 	u = &bw_upcalls[bw_upcalls_n++];
2439 	u->bu_src = x->bm_mfc->mfc_origin;
2440 	u->bu_dst = x->bm_mfc->mfc_mcastgrp;
2441 	u->bu_threshold.b_time = x->bm_threshold.b_time;
2442 	u->bu_threshold.b_packets = x->bm_threshold.b_packets;
2443 	u->bu_threshold.b_bytes = x->bm_threshold.b_bytes;
2444 	u->bu_measured.b_time = delta;
2445 	u->bu_measured.b_packets = x->bm_measured.b_packets;
2446 	u->bu_measured.b_bytes = x->bm_measured.b_bytes;
2447 	u->bu_flags = 0;
2448 	if (x->bm_flags & BW_METER_UNIT_PACKETS)
2449 		u->bu_flags |= BW_UPCALL_UNIT_PACKETS;
2450 	if (x->bm_flags & BW_METER_UNIT_BYTES)
2451 		u->bu_flags |= BW_UPCALL_UNIT_BYTES;
2452 	if (x->bm_flags & BW_METER_GEQ)
2453 		u->bu_flags |= BW_UPCALL_GEQ;
2454 	if (x->bm_flags & BW_METER_LEQ)
2455 		u->bu_flags |= BW_UPCALL_LEQ;
2456 }
2457 
2458 /*
2459  * Send the pending bandwidth-related upcalls
2460  */
2461 static void
bw_upcalls_send(void)2462 bw_upcalls_send(void)
2463 {
2464 	struct mbuf *m;
2465 	int len = bw_upcalls_n * sizeof(bw_upcalls[0]);
2466 	struct sockaddr_in k_igmpsrc = {
2467 		.sin_len = sizeof(k_igmpsrc),
2468 		.sin_family = AF_INET,
2469 	};
2470 	static struct igmpmsg igmpmsg = {
2471 		0,		/* unused1 */
2472 		0,		/* unused2 */
2473 		IGMPMSG_BW_UPCALL,/* im_msgtype */
2474 		0,		/* im_mbz */
2475 		0,		/* im_vif */
2476 		0,		/* unused3 */
2477 		{ 0 },		/* im_src */
2478 		{ 0 }		/* im_dst */
2479 	};
2480 
2481 	if (bw_upcalls_n == 0)
2482 		return;			/* No pending upcalls */
2483 
2484 	bw_upcalls_n = 0;
2485 
2486 	/*
2487 	 * Allocate a new mbuf, initialize it with the header and
2488 	 * the payload for the pending calls.
2489 	 */
2490 	MGETHDR(m, M_DONTWAIT, MT_HEADER);
2491 	if (m == NULL) {
2492 		log(LOG_WARNING, "bw_upcalls_send: cannot allocate mbuf\n");
2493 		return;
2494 	}
2495 
2496 	m->m_len = m->m_pkthdr.len = 0;
2497 	m_copyback(m, 0, sizeof(struct igmpmsg), (void *)&igmpmsg);
2498 	m_copyback(m, sizeof(struct igmpmsg), len, (void *)&bw_upcalls[0]);
2499 
2500 	/*
2501 	 * Send the upcalls
2502 	 * XXX do we need to set the address in k_igmpsrc ?
2503 	 */
2504 	mrtstat.mrts_upcalls++;
2505 	if (socket_send(ip_mrouter, m, &k_igmpsrc) < 0) {
2506 		log(LOG_WARNING, "bw_upcalls_send: ip_mrouter socket queue full\n");
2507 		++mrtstat.mrts_upq_sockfull;
2508 	}
2509 }
2510 
2511 /*
2512  * Compute the timeout hash value for the bw_meter entries
2513  */
2514 #define	BW_METER_TIMEHASH(bw_meter, hash)				\
2515     do {								\
2516 	struct timeval next_timeval = (bw_meter)->bm_start_time;	\
2517 	BW_TIMEVALADD(&next_timeval, &(bw_meter)->bm_threshold.b_time);	\
2518 	(hash) = next_timeval.tv_sec;					\
2519 	if (next_timeval.tv_usec)					\
2520 		(hash)++; /* XXX: make sure we don't timeout early */	\
2521 	(hash) %= BW_METER_BUCKETS;					\
2522     } while (/*CONSTCOND*/ 0)
2523 
2524 /*
2525  * Schedule a timer to process periodically bw_meter entry of type "<="
2526  * by linking the entry in the proper hash bucket.
2527  */
2528 static void
schedule_bw_meter(struct bw_meter * x,struct timeval * nowp)2529 schedule_bw_meter(struct bw_meter *x, struct timeval *nowp)
2530 {
2531 	int time_hash;
2532 
2533 	if (!(x->bm_flags & BW_METER_LEQ))
2534 		return;		/* XXX: we schedule timers only for "<=" entries */
2535 
2536 	/*
2537 	 * Reset the bw_meter entry
2538 	 */
2539 	x->bm_start_time = *nowp;
2540 	x->bm_measured.b_packets = 0;
2541 	x->bm_measured.b_bytes = 0;
2542 	x->bm_flags &= ~BW_METER_UPCALL_DELIVERED;
2543 
2544 	/*
2545 	 * Compute the timeout hash value and insert the entry
2546 	 */
2547 	BW_METER_TIMEHASH(x, time_hash);
2548 	x->bm_time_next = bw_meter_timers[time_hash];
2549 	bw_meter_timers[time_hash] = x;
2550 	x->bm_time_hash = time_hash;
2551 }
2552 
2553 /*
2554  * Unschedule the periodic timer that processes bw_meter entry of type "<="
2555  * by removing the entry from the proper hash bucket.
2556  */
2557 static void
unschedule_bw_meter(struct bw_meter * x)2558 unschedule_bw_meter(struct bw_meter *x)
2559 {
2560 	int time_hash;
2561 	struct bw_meter *prev, *tmp;
2562 
2563 	if (!(x->bm_flags & BW_METER_LEQ))
2564 		return;		/* XXX: we schedule timers only for "<=" entries */
2565 
2566 	/*
2567 	 * Compute the timeout hash value and delete the entry
2568 	 */
2569 	time_hash = x->bm_time_hash;
2570 	if (time_hash >= BW_METER_BUCKETS)
2571 		return;		/* Entry was not scheduled */
2572 
2573 	for (prev = NULL, tmp = bw_meter_timers[time_hash];
2574 	     tmp != NULL; prev = tmp, tmp = tmp->bm_time_next)
2575 		if (tmp == x)
2576 			break;
2577 
2578 	if (tmp == NULL)
2579 		panic("unschedule_bw_meter: bw_meter entry not found");
2580 
2581 	if (prev != NULL)
2582 		prev->bm_time_next = x->bm_time_next;
2583 	else
2584 		bw_meter_timers[time_hash] = x->bm_time_next;
2585 
2586 	x->bm_time_next = NULL;
2587 	x->bm_time_hash = BW_METER_BUCKETS;
2588 }
2589 
2590 /*
2591  * Process all "<=" type of bw_meter that should be processed now,
2592  * and for each entry prepare an upcall if necessary. Each processed
2593  * entry is rescheduled again for the (periodic) processing.
2594  *
2595  * This is run periodically (once per second normally). On each round,
2596  * all the potentially matching entries are in the hash slot that we are
2597  * looking at.
2598  */
2599 static void
bw_meter_process(void)2600 bw_meter_process(void)
2601 {
2602 	int s;
2603 	static uint32_t last_tv_sec;	/* last time we processed this */
2604 
2605 	uint32_t loops;
2606 	int i;
2607 	struct timeval now, process_endtime;
2608 
2609 	microtime(&now);
2610 	if (last_tv_sec == now.tv_sec)
2611 		return;		/* nothing to do */
2612 
2613 	loops = now.tv_sec - last_tv_sec;
2614 	last_tv_sec = now.tv_sec;
2615 	if (loops > BW_METER_BUCKETS)
2616 		loops = BW_METER_BUCKETS;
2617 
2618 	s = splsoftnet();
2619 	/*
2620 	 * Process all bins of bw_meter entries from the one after the last
2621 	 * processed to the current one. On entry, i points to the last bucket
2622 	 * visited, so we need to increment i at the beginning of the loop.
2623 	 */
2624 	for (i = (now.tv_sec - loops) % BW_METER_BUCKETS; loops > 0; loops--) {
2625 		struct bw_meter *x, *tmp_list;
2626 
2627 		if (++i >= BW_METER_BUCKETS)
2628 			i = 0;
2629 
2630 		/* Disconnect the list of bw_meter entries from the bin */
2631 		tmp_list = bw_meter_timers[i];
2632 		bw_meter_timers[i] = NULL;
2633 
2634 		/* Process the list of bw_meter entries */
2635 		while (tmp_list != NULL) {
2636 			x = tmp_list;
2637 			tmp_list = tmp_list->bm_time_next;
2638 
2639 			/* Test if the time interval is over */
2640 			process_endtime = x->bm_start_time;
2641 			BW_TIMEVALADD(&process_endtime, &x->bm_threshold.b_time);
2642 			if (BW_TIMEVALCMP(&process_endtime, &now, >)) {
2643 				/* Not yet: reschedule, but don't reset */
2644 				int time_hash;
2645 
2646 				BW_METER_TIMEHASH(x, time_hash);
2647 				if (time_hash == i && process_endtime.tv_sec == now.tv_sec) {
2648 					/*
2649 					 * XXX: somehow the bin processing is a bit ahead of time.
2650 					 * Put the entry in the next bin.
2651 					 */
2652 					if (++time_hash >= BW_METER_BUCKETS)
2653 						time_hash = 0;
2654 				}
2655 				x->bm_time_next = bw_meter_timers[time_hash];
2656 				bw_meter_timers[time_hash] = x;
2657 				x->bm_time_hash = time_hash;
2658 
2659 				continue;
2660 			}
2661 
2662 			/*
2663 			 * Test if we should deliver an upcall
2664 			 */
2665 			if (((x->bm_flags & BW_METER_UNIT_PACKETS) &&
2666 			    (x->bm_measured.b_packets <= x->bm_threshold.b_packets)) ||
2667 			    ((x->bm_flags & BW_METER_UNIT_BYTES) &&
2668 			    (x->bm_measured.b_bytes <= x->bm_threshold.b_bytes))) {
2669 				/* Prepare an upcall for delivery */
2670 				bw_meter_prepare_upcall(x, &now);
2671 			}
2672 
2673 			/*
2674 			  * Reschedule for next processing
2675 			 */
2676 			schedule_bw_meter(x, &now);
2677 		}
2678 	}
2679 
2680 	/* Send all upcalls that are pending delivery */
2681 	bw_upcalls_send();
2682 
2683 	splx(s);
2684 }
2685 
2686 /*
2687  * A periodic function for sending all upcalls that are pending delivery
2688  */
2689 static void
expire_bw_upcalls_send(void * unused)2690 expire_bw_upcalls_send(void *unused)
2691 {
2692 	int s;
2693 
2694 	s = splsoftnet();
2695 	bw_upcalls_send();
2696 	splx(s);
2697 
2698 	callout_reset(&bw_upcalls_ch, BW_UPCALLS_PERIOD,
2699 	    expire_bw_upcalls_send, NULL);
2700 }
2701 
2702 /*
2703  * A periodic function for periodic scanning of the multicast forwarding
2704  * table for processing all "<=" bw_meter entries.
2705  */
2706 static void
expire_bw_meter_process(void * unused)2707 expire_bw_meter_process(void *unused)
2708 {
2709 	if (mrt_api_config & MRT_MFC_BW_UPCALL)
2710 		bw_meter_process();
2711 
2712 	callout_reset(&bw_meter_ch, BW_METER_PERIOD,
2713 	    expire_bw_meter_process, NULL);
2714 }
2715 
2716 /*
2717  * End of bandwidth monitoring code
2718  */
2719 
2720 #ifdef PIM
2721 /*
2722  * Send the packet up to the user daemon, or eventually do kernel encapsulation
2723  */
2724 static int
pim_register_send(struct ip * ip,struct vif * vifp,struct mbuf * m,struct mfc * rt)2725 pim_register_send(struct ip *ip, struct vif *vifp, struct mbuf *m,
2726     struct mfc *rt)
2727 {
2728 	struct mbuf *mb_copy, *mm;
2729 
2730 	if (mrtdebug & DEBUG_PIM)
2731 		log(LOG_DEBUG, "pim_register_send: \n");
2732 
2733 	mb_copy = pim_register_prepare(ip, m);
2734 	if (mb_copy == NULL)
2735 		return ENOBUFS;
2736 
2737 	/*
2738 	 * Send all the fragments. Note that the mbuf for each fragment
2739 	 * is freed by the sending machinery.
2740 	 */
2741 	for (mm = mb_copy; mm; mm = mb_copy) {
2742 		mb_copy = mm->m_nextpkt;
2743 		mm->m_nextpkt = NULL;
2744 		mm = m_pullup(mm, sizeof(struct ip));
2745 		if (mm != NULL) {
2746 			ip = mtod(mm, struct ip *);
2747 			if ((mrt_api_config & MRT_MFC_RP) &&
2748 			    !in_nullhost(rt->mfc_rp)) {
2749 				pim_register_send_rp(ip, vifp, mm, rt);
2750 			} else {
2751 				pim_register_send_upcall(ip, vifp, mm, rt);
2752 			}
2753 		}
2754 	}
2755 
2756 	return 0;
2757 }
2758 
2759 /*
2760  * Return a copy of the data packet that is ready for PIM Register
2761  * encapsulation.
2762  * XXX: Note that in the returned copy the IP header is a valid one.
2763  */
2764 static struct mbuf *
pim_register_prepare(struct ip * ip,struct mbuf * m)2765 pim_register_prepare(struct ip *ip, struct mbuf *m)
2766 {
2767 	struct mbuf *mb_copy = NULL;
2768 	int mtu;
2769 
2770 	/* Take care of delayed checksums */
2771 	if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
2772 		in_undefer_cksum_tcpudp(m);
2773 		m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4);
2774 	}
2775 
2776 	/*
2777 	 * Copy the old packet & pullup its IP header into the
2778 	 * new mbuf so we can modify it.
2779 	 */
2780 	mb_copy = m_copypacket(m, M_DONTWAIT);
2781 	if (mb_copy == NULL)
2782 		return NULL;
2783 	mb_copy = m_pullup(mb_copy, ip->ip_hl << 2);
2784 	if (mb_copy == NULL)
2785 		return NULL;
2786 
2787 	/* take care of the TTL */
2788 	ip = mtod(mb_copy, struct ip *);
2789 	--ip->ip_ttl;
2790 
2791 	/* Compute the MTU after the PIM Register encapsulation */
2792 	mtu = 0xffff - sizeof(pim_encap_iphdr) - sizeof(pim_encap_pimhdr);
2793 
2794 	if (ntohs(ip->ip_len) <= mtu) {
2795 		/* Turn the IP header into a valid one */
2796 		ip->ip_sum = 0;
2797 		ip->ip_sum = in_cksum(mb_copy, ip->ip_hl << 2);
2798 	} else {
2799 		/* Fragment the packet */
2800 		if (ip_fragment(mb_copy, NULL, mtu) != 0) {
2801 			/* XXX: mb_copy was freed by ip_fragment() */
2802 			return NULL;
2803 		}
2804 	}
2805 	return mb_copy;
2806 }
2807 
2808 /*
2809  * Send an upcall with the data packet to the user-level process.
2810  */
2811 static int
pim_register_send_upcall(struct ip * ip,struct vif * vifp,struct mbuf * mb_copy,struct mfc * rt)2812 pim_register_send_upcall(struct ip *ip, struct vif *vifp,
2813     struct mbuf *mb_copy, struct mfc *rt)
2814 {
2815 	struct mbuf *mb_first;
2816 	int len = ntohs(ip->ip_len);
2817 	struct igmpmsg *im;
2818 	struct sockaddr_in k_igmpsrc = {
2819 		.sin_len = sizeof(k_igmpsrc),
2820 		.sin_family = AF_INET,
2821 	};
2822 
2823 	/*
2824 	 * Add a new mbuf with an upcall header
2825 	 */
2826 	MGETHDR(mb_first, M_DONTWAIT, MT_HEADER);
2827 	if (mb_first == NULL) {
2828 		m_freem(mb_copy);
2829 		return ENOBUFS;
2830 	}
2831 	mb_first->m_data += max_linkhdr;
2832 	mb_first->m_pkthdr.len = len + sizeof(struct igmpmsg);
2833 	mb_first->m_len = sizeof(struct igmpmsg);
2834 	mb_first->m_next = mb_copy;
2835 
2836 	/* Send message to routing daemon */
2837 	im = mtod(mb_first, struct igmpmsg *);
2838 	im->im_msgtype	= IGMPMSG_WHOLEPKT;
2839 	im->im_mbz	= 0;
2840 	im->im_vif	= vifp - viftable;
2841 	im->im_src	= ip->ip_src;
2842 	im->im_dst	= ip->ip_dst;
2843 
2844 	k_igmpsrc.sin_addr	= ip->ip_src;
2845 
2846 	mrtstat.mrts_upcalls++;
2847 
2848 	if (socket_send(ip_mrouter, mb_first, &k_igmpsrc) < 0) {
2849 		if (mrtdebug & DEBUG_PIM)
2850 			log(LOG_WARNING,
2851 			    "mcast: pim_register_send_upcall: ip_mrouter socket queue full\n");
2852 		++mrtstat.mrts_upq_sockfull;
2853 		return ENOBUFS;
2854 	}
2855 
2856 	/* Keep statistics */
2857 	pimstat.pims_snd_registers_msgs++;
2858 	pimstat.pims_snd_registers_bytes += len;
2859 
2860 	return 0;
2861 }
2862 
2863 /*
2864  * Encapsulate the data packet in PIM Register message and send it to the RP.
2865  */
2866 static int
pim_register_send_rp(struct ip * ip,struct vif * vifp,struct mbuf * mb_copy,struct mfc * rt)2867 pim_register_send_rp(struct ip *ip, struct vif *vifp,
2868     struct mbuf *mb_copy, struct mfc *rt)
2869 {
2870 	struct mbuf *mb_first;
2871 	struct ip *ip_outer;
2872 	struct pim_encap_pimhdr *pimhdr;
2873 	int len = ntohs(ip->ip_len);
2874 	vifi_t vifi = rt->mfc_parent;
2875 
2876 	if ((vifi >= numvifs) || in_nullhost(viftable[vifi].v_lcl_addr)) {
2877 		m_freem(mb_copy);
2878 		return EADDRNOTAVAIL;		/* The iif vif is invalid */
2879 	}
2880 
2881 	/*
2882 	 * Add a new mbuf with the encapsulating header
2883 	 */
2884 	MGETHDR(mb_first, M_DONTWAIT, MT_HEADER);
2885 	if (mb_first == NULL) {
2886 		m_freem(mb_copy);
2887 		return ENOBUFS;
2888 	}
2889 	mb_first->m_data += max_linkhdr;
2890 	mb_first->m_len = sizeof(pim_encap_iphdr) + sizeof(pim_encap_pimhdr);
2891 	mb_first->m_next = mb_copy;
2892 
2893 	mb_first->m_pkthdr.len = len + mb_first->m_len;
2894 
2895 	/*
2896 	 * Fill in the encapsulating IP and PIM header
2897 	 */
2898 	ip_outer = mtod(mb_first, struct ip *);
2899 	*ip_outer = pim_encap_iphdr;
2900 	if (mb_first->m_pkthdr.len < IP_MINFRAGSIZE)
2901 		ip_outer->ip_id = 0;
2902 	else
2903 		ip_outer->ip_id = ip_newid(NULL);
2904 	ip_outer->ip_len = htons(len + sizeof(pim_encap_iphdr) +
2905 	    sizeof(pim_encap_pimhdr));
2906 	ip_outer->ip_src = viftable[vifi].v_lcl_addr;
2907 	ip_outer->ip_dst = rt->mfc_rp;
2908 	/*
2909 	 * Copy the inner header TOS to the outer header, and take care of the
2910 	 * IP_DF bit.
2911 	 */
2912 	ip_outer->ip_tos = ip->ip_tos;
2913 	if (ntohs(ip->ip_off) & IP_DF)
2914 		ip_outer->ip_off |= htons(IP_DF);
2915 	pimhdr = (struct pim_encap_pimhdr *)((char *)ip_outer
2916 	    + sizeof(pim_encap_iphdr));
2917 	*pimhdr = pim_encap_pimhdr;
2918 	/* If the iif crosses a border, set the Border-bit */
2919 	if (rt->mfc_flags[vifi] & MRT_MFC_FLAGS_BORDER_VIF & mrt_api_config)
2920 		pimhdr->flags |= htonl(PIM_BORDER_REGISTER);
2921 
2922 	mb_first->m_data += sizeof(pim_encap_iphdr);
2923 	pimhdr->pim.pim_cksum = in_cksum(mb_first, sizeof(pim_encap_pimhdr));
2924 	mb_first->m_data -= sizeof(pim_encap_iphdr);
2925 
2926 	if (vifp->v_rate_limit == 0)
2927 		tbf_send_packet(vifp, mb_first);
2928 	else
2929 		tbf_control(vifp, mb_first, ip, ntohs(ip_outer->ip_len));
2930 
2931 	/* Keep statistics */
2932 	pimstat.pims_snd_registers_msgs++;
2933 	pimstat.pims_snd_registers_bytes += len;
2934 
2935 	return 0;
2936 }
2937 
2938 /*
2939  * PIM-SMv2 and PIM-DM messages processing.
2940  * Receives and verifies the PIM control messages, and passes them
2941  * up to the listening socket, using rip_input().
2942  * The only message with special processing is the PIM_REGISTER message
2943  * (used by PIM-SM): the PIM header is stripped off, and the inner packet
2944  * is passed to if_simloop().
2945  */
2946 void
pim_input(struct mbuf * m,int off,int proto)2947 pim_input(struct mbuf *m, int off, int proto)
2948 {
2949 	struct ip *ip = mtod(m, struct ip *);
2950 	struct pim *pim;
2951 	int minlen;
2952 	int datalen;
2953 	int ip_tos;
2954 	int iphlen;
2955 
2956 	iphlen = off;
2957 	datalen = ntohs(ip->ip_len) - iphlen;
2958 
2959 	/* Keep statistics */
2960 	pimstat.pims_rcv_total_msgs++;
2961 	pimstat.pims_rcv_total_bytes += datalen;
2962 
2963 	/*
2964 	 * Validate lengths
2965 	 */
2966 	if (datalen < PIM_MINLEN) {
2967 		pimstat.pims_rcv_tooshort++;
2968 		log(LOG_ERR, "pim_input: packet size too small %d from %lx\n",
2969 		    datalen, (u_long)ip->ip_src.s_addr);
2970 		m_freem(m);
2971 		return;
2972 	}
2973 
2974 	/*
2975 	 * If the packet is at least as big as a REGISTER, go ahead
2976 	 * and grab the PIM REGISTER header size, to avoid another
2977 	 * possible m_pullup() later.
2978 	 *
2979 	 * PIM_MINLEN       == pimhdr + u_int32_t == 4 + 4 = 8
2980 	 * PIM_REG_MINLEN   == pimhdr + reghdr + encap_iphdr == 4 + 4 + 20 = 28
2981 	 */
2982 	minlen = iphlen + (datalen >= PIM_REG_MINLEN ? PIM_REG_MINLEN : PIM_MINLEN);
2983 
2984 	/*
2985 	 * Get the IP and PIM headers in contiguous memory, and
2986 	 * possibly the PIM REGISTER header.
2987 	 */
2988 	if ((m->m_flags & M_EXT || m->m_len < minlen) &&
2989 	    (m = m_pullup(m, minlen)) == NULL) {
2990 		log(LOG_ERR, "pim_input: m_pullup failure\n");
2991 		return;
2992 	}
2993 	ip = mtod(m, struct ip *);
2994 	ip_tos = ip->ip_tos;
2995 
2996 	/* adjust mbuf to point to the PIM header */
2997 	m->m_data += iphlen;
2998 	m->m_len  -= iphlen;
2999 	pim = mtod(m, struct pim *);
3000 
3001 	/*
3002 	 * Validate checksum. If PIM REGISTER, exclude the data packet.
3003 	 *
3004 	 * XXX: some older PIMv2 implementations don't make this distinction,
3005 	 * so for compatibility reason perform the checksum over part of the
3006 	 * message, and if error, then over the whole message.
3007 	 */
3008 	if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER && in_cksum(m, PIM_MINLEN) == 0) {
3009 		/* do nothing, checksum okay */
3010 	} else if (in_cksum(m, datalen)) {
3011 		pimstat.pims_rcv_badsum++;
3012 		if (mrtdebug & DEBUG_PIM)
3013 			log(LOG_DEBUG, "pim_input: invalid checksum\n");
3014 		m_freem(m);
3015 		return;
3016 	}
3017 
3018 	/* PIM version check */
3019 	if (PIM_VT_V(pim->pim_vt) < PIM_VERSION) {
3020 		pimstat.pims_rcv_badversion++;
3021 		log(LOG_ERR, "pim_input: incorrect version %d, expecting %d\n",
3022 		    PIM_VT_V(pim->pim_vt), PIM_VERSION);
3023 		m_freem(m);
3024 		return;
3025 	}
3026 
3027 	/* restore mbuf back to the outer IP */
3028 	m->m_data -= iphlen;
3029 	m->m_len  += iphlen;
3030 
3031 	if (PIM_VT_T(pim->pim_vt) == PIM_REGISTER) {
3032 		/*
3033 		 * Since this is a REGISTER, we'll make a copy of the register
3034 		 * headers ip + pim + u_int32 + encap_ip, to be passed up to the
3035 		 * routing daemon.
3036 		 */
3037 		int s;
3038 		struct sockaddr_in dst = {
3039 			.sin_len = sizeof(dst),
3040 			.sin_family = AF_INET,
3041 		};
3042 		struct mbuf *mcp;
3043 		struct ip *encap_ip;
3044 		u_int32_t *reghdr;
3045 		struct ifnet *vifp;
3046 
3047 		s = splsoftnet();
3048 		if ((reg_vif_num >= numvifs) || (reg_vif_num == VIFI_INVALID)) {
3049 			splx(s);
3050 			if (mrtdebug & DEBUG_PIM)
3051 				log(LOG_DEBUG,
3052 				    "pim_input: register vif not set: %d\n", reg_vif_num);
3053 			m_freem(m);
3054 			return;
3055 		}
3056 		/* XXX need refcnt? */
3057 		vifp = viftable[reg_vif_num].v_ifp;
3058 		splx(s);
3059 
3060 		/*
3061 		 * Validate length
3062 		 */
3063 		if (datalen < PIM_REG_MINLEN) {
3064 			pimstat.pims_rcv_tooshort++;
3065 			pimstat.pims_rcv_badregisters++;
3066 			log(LOG_ERR,
3067 			    "pim_input: register packet size too small %d from %lx\n",
3068 			    datalen, (u_long)ip->ip_src.s_addr);
3069 			m_freem(m);
3070 			return;
3071 		}
3072 
3073 		reghdr = (u_int32_t *)(pim + 1);
3074 		encap_ip = (struct ip *)(reghdr + 1);
3075 
3076 		if (mrtdebug & DEBUG_PIM) {
3077 			log(LOG_DEBUG,
3078 			    "pim_input[register], encap_ip: %lx -> %lx, encap_ip len %d\n",
3079 			    (u_long)ntohl(encap_ip->ip_src.s_addr),
3080 			    (u_long)ntohl(encap_ip->ip_dst.s_addr),
3081 			    ntohs(encap_ip->ip_len));
3082 		}
3083 
3084 		/* verify the version number of the inner packet */
3085 		if (encap_ip->ip_v != IPVERSION) {
3086 			pimstat.pims_rcv_badregisters++;
3087 			if (mrtdebug & DEBUG_PIM) {
3088 				log(LOG_DEBUG, "pim_input: invalid IP version (%d) "
3089 				    "of the inner packet\n", encap_ip->ip_v);
3090 			}
3091 			m_freem(m);
3092 			return;
3093 		}
3094 
3095 		/* verify the inner packet doesn't have options */
3096 		if (encap_ip->ip_hl != (sizeof(struct ip) >> 2)) {
3097 			pimstat.pims_rcv_badregisters++;
3098 			m_freem(m);
3099 			return;
3100 		}
3101 
3102 		/* verify the inner packet is destined to a mcast group */
3103 		if (!IN_MULTICAST(encap_ip->ip_dst.s_addr)) {
3104 			pimstat.pims_rcv_badregisters++;
3105 			 if (mrtdebug & DEBUG_PIM)
3106 				log(LOG_DEBUG,
3107 				    "pim_input: inner packet of register is not "
3108 				    "multicast %lx\n",
3109 				    (u_long)ntohl(encap_ip->ip_dst.s_addr));
3110 			m_freem(m);
3111 			return;
3112 		}
3113 
3114 		/* If a NULL_REGISTER, pass it to the daemon */
3115 		if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
3116 			goto pim_input_to_daemon;
3117 
3118 		/*
3119 		 * Copy the TOS from the outer IP header to the inner IP header.
3120 		 */
3121 		if (encap_ip->ip_tos != ip_tos) {
3122 			/* Outer TOS -> inner TOS */
3123 			encap_ip->ip_tos = ip_tos;
3124 			/* Recompute the inner header checksum. Sigh... */
3125 
3126 			/* adjust mbuf to point to the inner IP header */
3127 			m->m_data += (iphlen + PIM_MINLEN);
3128 			m->m_len  -= (iphlen + PIM_MINLEN);
3129 
3130 			encap_ip->ip_sum = 0;
3131 			encap_ip->ip_sum = in_cksum(m, encap_ip->ip_hl << 2);
3132 
3133 			/* restore mbuf to point back to the outer IP header */
3134 			m->m_data -= (iphlen + PIM_MINLEN);
3135 			m->m_len  += (iphlen + PIM_MINLEN);
3136 		}
3137 
3138 		/*
3139 		 * Decapsulate the inner IP packet and loopback to forward it
3140 		 * as a normal multicast packet. Also, make a copy of the
3141 		 *     outer_iphdr + pimhdr + reghdr + encap_iphdr
3142 		 * to pass to the daemon later, so it can take the appropriate
3143 		 * actions (e.g., send back PIM_REGISTER_STOP).
3144 		 * XXX: here m->m_data points to the outer IP header.
3145 		 */
3146 		mcp = m_copym(m, 0, iphlen + PIM_REG_MINLEN, M_DONTWAIT);
3147 		if (mcp == NULL) {
3148 			log(LOG_ERR,
3149 			    "pim_input: pim register: could not copy register head\n");
3150 			m_freem(m);
3151 			return;
3152 		}
3153 
3154 		/* Keep statistics */
3155 		/* XXX: registers_bytes include only the encap. mcast pkt */
3156 		pimstat.pims_rcv_registers_msgs++;
3157 		pimstat.pims_rcv_registers_bytes += ntohs(encap_ip->ip_len);
3158 
3159 		/*
3160 		 * forward the inner ip packet; point m_data at the inner ip.
3161 		 */
3162 		m_adj(m, iphlen + PIM_MINLEN);
3163 
3164 		if (mrtdebug & DEBUG_PIM) {
3165 			log(LOG_DEBUG,
3166 			    "pim_input: forwarding decapsulated register: "
3167 			    "src %lx, dst %lx, vif %d\n",
3168 			    (u_long)ntohl(encap_ip->ip_src.s_addr),
3169 			    (u_long)ntohl(encap_ip->ip_dst.s_addr),
3170 			    reg_vif_num);
3171 		}
3172 		/* NB: vifp was collected above; can it change on us? */
3173 		looutput(vifp, m, (struct sockaddr *)&dst, NULL);
3174 
3175 		/* prepare the register head to send to the mrouting daemon */
3176 		m = mcp;
3177 	}
3178 
3179 pim_input_to_daemon:
3180 	/*
3181 	 * Pass the PIM message up to the daemon; if it is a Register message,
3182 	 * pass the 'head' only up to the daemon. This includes the
3183 	 * outer IP header, PIM header, PIM-Register header and the
3184 	 * inner IP header.
3185 	 * XXX: the outer IP header pkt size of a Register is not adjust to
3186 	 * reflect the fact that the inner multicast data is truncated.
3187 	 */
3188 	/*
3189 	 * Currently, pim_input() is always called holding softnet_lock
3190 	 * by ipintr()(!NET_MPSAFE) or PR_INPUT_WRAP()(NET_MPSAFE).
3191 	 */
3192 	KASSERT(mutex_owned(softnet_lock));
3193 	rip_input(m, iphlen, proto);
3194 
3195 	return;
3196 }
3197 #endif /* PIM */
3198