xref: /netbsd-src/sys/external/bsd/ipf/netinet/ip_fil_netbsd.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: ip_fil_netbsd.c,v 1.7 2013/11/01 06:42:23 mrg Exp $	*/
2 
3 /*
4  * Copyright (C) 2012 by Darren Reed.
5  *
6  * See the IPFILTER.LICENCE file for details on licencing.
7  */
8 #if !defined(lint)
9 #if defined(__NetBSD__)
10 #include <sys/cdefs.h>
11 __KERNEL_RCSID(0, "$NetBSD: ip_fil_netbsd.c,v 1.7 2013/11/01 06:42:23 mrg Exp $");
12 #else
13 static const char sccsid[] = "@(#)ip_fil.c	2.41 6/5/96 (C) 1993-2000 Darren Reed";
14 static const char rcsid[] = "@(#)Id: ip_fil_netbsd.c,v 1.1.1.2 2012/07/22 13:45:17 darrenr Exp";
15 #endif
16 #endif
17 
18 #if defined(KERNEL) || defined(_KERNEL)
19 # undef KERNEL
20 # undef _KERNEL
21 # define        KERNEL	1
22 # define        _KERNEL	1
23 #endif
24 #include <sys/param.h>
25 #if (NetBSD >= 199905) && !defined(IPFILTER_LKM)
26 # include "opt_ipsec.h"
27 #endif
28 #include <sys/errno.h>
29 #include <sys/types.h>
30 #include <sys/file.h>
31 #include <sys/ioctl.h>
32 #include <sys/time.h>
33 #include <sys/systm.h>
34 #include <sys/select.h>
35 #if (NetBSD > 199609)
36 # include <sys/dirent.h>
37 #else
38 # include <sys/dir.h>
39 #endif
40 #if (__NetBSD_Version__ >= 599005900)
41 # include <sys/cprng.h>
42 #endif
43 #include <sys/mbuf.h>
44 #include <sys/protosw.h>
45 #include <sys/socket.h>
46 #include <sys/poll.h>
47 #if (__NetBSD_Version__ >= 399002000)
48 # include <sys/kauth.h>
49 #endif
50 
51 #include <net/if.h>
52 #include <net/route.h>
53 #include <netinet/in.h>
54 #include <netinet/in_var.h>
55 #include <netinet/in_systm.h>
56 #include <netinet/ip.h>
57 #include <netinet/ip_var.h>
58 #include <netinet/tcp.h>
59 #if __NetBSD_Version__ >= 105190000	/* 1.5T */
60 # include <netinet/tcp_timer.h>
61 # include <netinet/tcp_var.h>
62 #endif
63 #include <netinet/udp.h>
64 #include <netinet/tcpip.h>
65 #include <netinet/ip_icmp.h>
66 #include "netinet/ip_compat.h"
67 #ifdef USE_INET6
68 # include <netinet/icmp6.h>
69 # if (__NetBSD_Version__ >= 106000000)
70 #  include <netinet6/nd6.h>
71 # endif
72 #endif
73 #include "netinet/ip_fil.h"
74 #include "netinet/ip_nat.h"
75 #include "netinet/ip_frag.h"
76 #include "netinet/ip_state.h"
77 #include "netinet/ip_proxy.h"
78 #include "netinet/ip_auth.h"
79 #include "netinet/ip_sync.h"
80 #include "netinet/ip_lookup.h"
81 #include "netinet/ip_dstlist.h"
82 #ifdef	IPFILTER_SCAN
83 #include "netinet/ip_scan.h"
84 #endif
85 #include <sys/md5.h>
86 #include <sys/kernel.h>
87 #include <sys/conf.h>
88 #ifdef INET
89 extern	int	ip_optcopy (struct ip *, struct ip *);
90 #endif
91 
92 #ifdef IPFILTER_M_IPFILTER
93 MALLOC_DEFINE(M_IPFILTER, "IP Filter", "IP Filter packet filter data structures");
94 #endif
95 
96 #if __NetBSD_Version__ >= 105009999
97 # define	csuminfo	csum_flags
98 #endif
99 
100 #if __NetBSD_Version__ < 200000000
101 extern	struct	protosw	inetsw[];
102 #endif
103 
104 #if (__NetBSD_Version__ >= 599002000)
105 static kauth_listener_t ipf_listener;
106 #endif
107 
108 #if (__NetBSD_Version__ < 399001400)
109 extern int ip6_getpmtu (struct route_in6 *, struct route_in6 *,
110 			    struct ifnet *, struct in6_addr *, u_long *,
111 			    int *);
112 #endif
113 #if (NetBSD >= 199511)
114 static  int     ipfopen(dev_t dev, int flags, int devtype, PROC_T *p);
115 static  int     ipfclose(dev_t dev, int flags, int devtype, PROC_T *p);
116 #else
117 # if (__NetBSD_Version__ >= 399001400)
118 static  int     ipfopen(dev_t dev, int flags, struct lwp *);
119 static  int     ipfclose(dev_t dev, int flags, struct lwp *);
120 # else
121 static  int     ipfopen(dev_t dev, int flags);
122 static  int     ipfclose(dev_t dev, int flags);
123 # endif /* __NetBSD_Version__ >= 399001400 */
124 #endif
125 static  int     ipfread(dev_t, struct uio *, int ioflag);
126 static  int     ipfwrite(dev_t, struct uio *, int ioflag);
127 static  int     ipfpoll(dev_t, int events, PROC_T *);
128 static	void	ipf_timer_func(void *ptr);
129 
130 const struct cdevsw ipl_cdevsw = {
131 	ipfopen, ipfclose, ipfread, ipfwrite, ipfioctl,
132 	nostop, notty, ipfpoll, nommap,
133 #if  (__NetBSD_Version__ >= 200000000)
134 	nokqfilter,
135 #endif
136 #ifdef D_OTHER
137 	D_OTHER,
138 #endif
139 };
140 
141 ipf_main_softc_t ipfmain;
142 
143 static	u_short	ipid = 0;
144 static	int	(*ipf_savep)(void *, ip_t *, int, void *, int, struct mbuf **);
145 static	int	ipf_send_ip(fr_info_t *, mb_t *);
146 #ifdef USE_INET6
147 static int ipf_fastroute6(struct mbuf *, struct mbuf **,
148 			      fr_info_t *, frdest_t *);
149 #endif
150 
151 #if defined(NETBSD_PF)
152 # include <net/pfil.h>
153 /*
154  * We provide the ipf_checkp name just to minimize changes later.
155  */
156 int (*ipf_checkp)(void *, ip_t *ip, int hlen, void *ifp, int out, mb_t **mp);
157 #endif /* NETBSD_PF */
158 
159 #if defined(__NetBSD_Version__) && (__NetBSD_Version__ >= 105110000)
160 # include <net/pfil.h>
161 
162 static int ipf_check_wrapper(void *, struct mbuf **, struct ifnet *, int );
163 
164 static int
165 ipf_check_wrapper(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
166 {
167 	struct ip *ip;
168 	int rv, hlen;
169 
170 #if __NetBSD_Version__ >= 200080000
171 	/*
172 	 * ensure that mbufs are writable beforehand
173 	 * as it's assumed by ipf code.
174 	 * XXX inefficient
175 	 */
176 	int error = m_makewritable(mp, 0, M_COPYALL, M_DONTWAIT);
177 
178 	if (error) {
179 		m_freem(*mp);
180 		*mp = NULL;
181 		return error;
182 	}
183 #endif
184 	ip = mtod(*mp, struct ip *);
185 	hlen = ip->ip_hl << 2;
186 
187 #ifdef INET
188 #if defined(M_CSUM_TCPv4)
189 	/*
190 	 * If the packet is out-bound, we can't delay checksums
191 	 * here.  For in-bound, the checksum has already been
192 	 * validated.
193 	 */
194 	if (dir == PFIL_OUT) {
195 		if ((*mp)->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
196 			in_delayed_cksum(*mp);
197 			(*mp)->m_pkthdr.csum_flags &=
198 			    ~(M_CSUM_TCPv4|M_CSUM_UDPv4);
199 		}
200 	}
201 #endif /* M_CSUM_TCPv4 */
202 #endif /* INET */
203 
204 	/*
205 	 * Note, we don't need to update the checksum, because
206 	 * it has already been verified.
207 	 */
208 	rv = ipf_check(&ipfmain, ip, hlen, ifp, (dir == PFIL_OUT), mp);
209 
210 	return (rv);
211 }
212 
213 # ifdef USE_INET6
214 #  include <netinet/ip6.h>
215 
216 static int ipf_check_wrapper6(void *, struct mbuf **, struct ifnet *, int );
217 
218 static int
219 ipf_check_wrapper6(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
220 {
221 #if defined(INET6)
222 #  if defined(M_CSUM_TCPv6) && (__NetBSD_Version__ > 200000000)
223 	/*
224 	 * If the packet is out-bound, we can't delay checksums
225 	 * here.  For in-bound, the checksum has already been
226 	 * validated.
227 	 */
228 	if (dir == PFIL_OUT) {
229 		if ((*mp)->m_pkthdr.csum_flags & (M_CSUM_TCPv6|M_CSUM_UDPv6)) {
230 #   if (__NetBSD_Version__ > 399000600)
231 			in6_delayed_cksum(*mp);
232 #   endif
233 			(*mp)->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv6|
234 							M_CSUM_UDPv6);
235 		}
236 	}
237 #  endif
238 #endif /* INET6 */
239 
240 	return (ipf_check(&ipfmain, mtod(*mp, struct ip *), sizeof(struct ip6_hdr),
241 	    ifp, (dir == PFIL_OUT), mp));
242 }
243 # endif
244 
245 
246 # if defined(PFIL_TYPE_IFNET) && defined(PFIL_IFNET)
247 static int ipf_pfilsync(void *, struct mbuf **, struct ifnet *, int);
248 
249 static int
250 ipf_pfilsync(void *hdr, struct mbuf **mp, struct ifnet *ifp, int dir)
251 {
252 	/*
253 	 * The interface pointer is useless for create (we have nothing to
254 	 * compare it to) and at detach, the interface name is still in the
255 	 * list of active NICs (albeit, down, but that's not any real
256 	 * indicator) and doing ifunit() on the name will still return the
257 	 * pointer, so it's not much use then, either.
258 	 */
259 	ipf_sync(&ipfmain, NULL);
260 	return 0;
261 }
262 # endif
263 
264 #endif /* __NetBSD_Version__ >= 105110000 */
265 
266 
267 #if defined(IPFILTER_LKM)
268 int
269 ipf_identify(s)
270 	char *s;
271 {
272 	if (strcmp(s, "ipl") == 0)
273 		return 1;
274 	return 0;
275 }
276 #endif /* IPFILTER_LKM */
277 
278 #if (__NetBSD_Version__ >= 599002000)
279 static int
280 ipf_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
281     void *arg0, void *arg1, void *arg2, void *arg3)
282 {
283 	int result;
284 	enum kauth_network_req req;
285 
286 	result = KAUTH_RESULT_DEFER;
287 	req = (enum kauth_network_req)arg0;
288 
289 	if (action != KAUTH_NETWORK_FIREWALL)
290 		return result;
291 
292 	/* These must have came from device context. */
293 	if ((req == KAUTH_REQ_NETWORK_FIREWALL_FW) ||
294 	    (req == KAUTH_REQ_NETWORK_FIREWALL_NAT))
295 		result = KAUTH_RESULT_ALLOW;
296 
297 	return result;
298 }
299 #endif
300 
301 /*
302  * Try to detect the case when compiling for NetBSD with pseudo-device
303  */
304 void
305 ipfilterattach(int count)
306 {
307 
308 #if (__NetBSD_Version__ >= 599002000)
309 	ipf_listener = kauth_listen_scope(KAUTH_SCOPE_NETWORK,
310 	    ipf_listener_cb, NULL);
311 #endif
312 
313 	if (ipf_load_all() == 0)
314 		(void) ipf_create_all(&ipfmain);
315 }
316 
317 
318 int
319 ipfattach(ipf_main_softc_t *softc)
320 {
321 	SPL_INT(s);
322 #if (__NetBSD_Version__ >= 499005500)
323 	int i;
324 #endif
325 #if defined(NETBSD_PF) && (__NetBSD_Version__ >= 104200000)
326 	int error = 0;
327 # if defined(__NetBSD_Version__) && (__NetBSD_Version__ >= 105110000)
328         pfil_head_t *ph_inet;
329 #  ifdef USE_INET6
330         pfil_head_t *ph_inet6;
331 #  endif
332 #  if defined(PFIL_TYPE_IFNET) && defined(PFIL_IFNET)
333         pfil_head_t *ph_ifsync;
334 #  endif
335 # endif
336 #endif
337 
338 	SPL_NET(s);
339 	if ((softc->ipf_running > 0) || (ipf_checkp == ipf_check)) {
340 		printf("IP Filter: already initialized\n");
341 		SPL_X(s);
342 		IPFERROR(130017);
343 		return EBUSY;
344 	}
345 
346 	if (ipf_init_all(softc) < 0) {
347 		SPL_X(s);
348 		IPFERROR(130015);
349 		return EIO;
350 	}
351 
352 #ifdef NETBSD_PF
353 # if (__NetBSD_Version__ >= 104200000)
354 #  if __NetBSD_Version__ >= 105110000
355 	ph_inet = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET);
356 #   ifdef USE_INET6
357 	ph_inet6 = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET6);
358 #   endif
359 #   if defined(PFIL_TYPE_IFNET) && defined(PFIL_IFNET)
360 	ph_ifsync = pfil_head_get(PFIL_TYPE_IFNET, 0);
361 #   endif
362 
363 	if (ph_inet == NULL
364 #   ifdef USE_INET6
365 	    && ph_inet6 == NULL
366 #   endif
367 #   if defined(PFIL_TYPE_IFNET) && defined(PFIL_IFNET)
368 	    && ph_ifsync == NULL
369 #   endif
370 	   ) {
371 		SPL_X(s);
372 		IPFERROR(130016);
373 		return ENODEV;
374 	}
375 
376 	if (ph_inet != NULL)
377 		error = pfil_add_hook((void *)ipf_check_wrapper, NULL,
378 				      PFIL_IN|PFIL_OUT, ph_inet);
379 	else
380 		error = 0;
381 #  else
382 	error = pfil_add_hook((void *)ipf_check, PFIL_IN|PFIL_OUT,
383 			      &inetsw[ip_protox[IPPROTO_IP]].pr_pfh);
384 #  endif
385 	if (error) {
386 		IPFERROR(130013);
387 		goto pfil_error;
388 	}
389 # else
390 	pfil_add_hook((void *)ipf_check, PFIL_IN|PFIL_OUT);
391 # endif
392 
393 # ifdef USE_INET6
394 #  if __NetBSD_Version__ >= 105110000
395 	if (ph_inet6 != NULL)
396 		error = pfil_add_hook((void *)ipf_check_wrapper6, NULL,
397 				      PFIL_IN|PFIL_OUT, ph_inet6);
398 	else
399 		error = 0;
400 	if (error) {
401 		pfil_remove_hook((void *)ipf_check_wrapper6, NULL,
402 				 PFIL_IN|PFIL_OUT, ph_inet6);
403 		ipfmain.ipf_interror = 130014;
404 		goto pfil_error;
405 	}
406 #  else
407 	error = pfil_add_hook((void *)ipf_check, PFIL_IN|PFIL_OUT,
408 			      &inetsw[ip_protox[IPPROTO_IPV6]].pr_pfh);
409 	if (error) {
410 		pfil_remove_hook((void *)ipf_check, PFIL_IN|PFIL_OUT,
411 				 &inetsw[ip_protox[IPPROTO_IP]].pr_pfh);
412 		IPFERROR(130014);
413 		goto pfil_error;
414 	}
415 #  endif
416 # endif
417 
418 # if defined(PFIL_TYPE_IFNET) && defined(PFIL_IFNET)
419 	if (ph_ifsync != NULL)
420 		(void) pfil_add_hook((void *)ipf_pfilsync, NULL,
421 				     PFIL_IFNET, ph_ifsync);
422 # endif
423 #endif
424 
425 #if (__NetBSD_Version__ >= 499005500)
426 	for (i = 0; i < IPL_LOGSIZE; i++)
427 		selinit(&ipfmain.ipf_selwait[i]);
428 #else
429 	bzero((char *)ipfmain.ipf_selwait, sizeof(ipfmain.ipf_selwait));
430 #endif
431 	ipf_savep = ipf_checkp;
432 	ipf_checkp = ipf_check;
433 
434 #ifdef INET
435 	if (softc->ipf_control_forwarding & 1)
436 		ipforwarding = 1;
437 #endif
438 
439 	ipid = 0;
440 
441 	SPL_X(s);
442 
443 #if (__NetBSD_Version__ >= 104010000)
444 # if (__NetBSD_Version__ >= 499002000)
445 	callout_init(&softc->ipf_slow_ch, 0);
446 # else
447 	callout_init(&softc->ipf_slow_ch);
448 # endif
449 	callout_reset(&softc->ipf_slow_ch, (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT,
450 		     ipf_timer_func, softc);
451 #else
452 	timeout(ipf_timer_func, softc, (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT);
453 #endif
454 
455 	return 0;
456 
457 #if __NetBSD_Version__ >= 105110000
458 pfil_error:
459 	SPL_X(s);
460 	ipf_fini_all(softc);
461 	return error;
462 #endif
463 }
464 
465 static void
466 ipf_timer_func(void *ptr)
467 {
468 	ipf_main_softc_t *softc = ptr;
469 	SPL_INT(s);
470 
471 	SPL_NET(s);
472 	READ_ENTER(&softc->ipf_global);
473 
474 	if (softc->ipf_running > 0)
475 		ipf_slowtimer(softc);
476 
477 	if (softc->ipf_running == -1 || softc->ipf_running == 1) {
478 #if NETBSD_GE_REV(104240000)
479 		callout_reset(&softc->ipf_slow_ch, hz / 2,
480 			      ipf_timer_func, softc);
481 #else
482 		timeout(ipf_timer_func, softc,
483 			(hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT);
484 #endif
485 	}
486 	RWLOCK_EXIT(&softc->ipf_global);
487 	SPL_X(s);
488 }
489 
490 
491 /*
492  * Disable the filter by removing the hooks from the IP input/output
493  * stream.
494  */
495 int
496 ipfdetach(ipf_main_softc_t *softc)
497 {
498 	SPL_INT(s);
499 #if (__NetBSD_Version__ >= 499005500)
500 	int i;
501 #endif
502 #if defined(NETBSD_PF) && (__NetBSD_Version__ >= 104200000)
503 	int error = 0;
504 # if __NetBSD_Version__ >= 105150000
505 	pfil_head_t *ph_inet = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET);
506 #  ifdef USE_INET6
507 	pfil_head_t *ph_inet6 = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET6);
508 #  endif
509 #  if defined(PFIL_TYPE_IFNET) && defined(PFIL_IFNET)
510 	struct pfil_head *ph_ifsync = pfil_head_get(PFIL_TYPE_IFNET, 0);
511 #  endif
512 # endif
513 #endif
514 
515 	SPL_NET(s);
516 
517 #if (__NetBSD_Version__ >= 104010000)
518 	if (softc->ipf_running > 0)
519 		callout_stop(&softc->ipf_slow_ch);
520 #else
521 	untimeout(ipf_slowtimer, NULL);
522 #endif /* NetBSD */
523 
524 	ipf_checkp = ipf_savep;
525 	(void) ipf_flush(softc, IPL_LOGIPF, FR_INQUE|FR_OUTQUE|FR_INACTIVE);
526 	(void) ipf_flush(softc, IPL_LOGIPF, FR_INQUE|FR_OUTQUE);
527 
528 #ifdef INET
529 	if (softc->ipf_control_forwarding & 2)
530 		ipforwarding = 0;
531 #endif
532 
533 #ifdef NETBSD_PF
534 # if (__NetBSD_Version__ >= 104200000)
535 #  if __NetBSD_Version__ >= 105110000
536 #   if defined(PFIL_TYPE_IFNET) && defined(PFIL_IFNET)
537 	(void) pfil_remove_hook((void *)ipf_pfilsync, NULL,
538 				PFIL_IFNET, ph_ifsync);
539 #   endif
540 
541 	if (ph_inet != NULL)
542 		error = pfil_remove_hook((void *)ipf_check_wrapper, NULL,
543 					 PFIL_IN|PFIL_OUT, ph_inet);
544 	else
545 		error = 0;
546 #  else
547 	error = pfil_remove_hook((void *)ipf_check, PFIL_IN|PFIL_OUT,
548 				 &inetsw[ip_protox[IPPROTO_IP]].pr_pfh);
549 #  endif
550 	if (error) {
551 		SPL_X(s);
552 		IPFERROR(130011);
553 		return error;
554 	}
555 # else
556 	pfil_remove_hook((void *)ipf_check, PFIL_IN|PFIL_OUT);
557 # endif
558 # ifdef USE_INET6
559 #  if __NetBSD_Version__ >= 105110000
560 	if (ph_inet6 != NULL)
561 		error = pfil_remove_hook((void *)ipf_check_wrapper6, NULL,
562 					 PFIL_IN|PFIL_OUT, ph_inet6);
563 	else
564 		error = 0;
565 #  else
566 	error = pfil_remove_hook((void *)ipf_check, PFIL_IN|PFIL_OUT,
567 				 &inetsw[ip_protox[IPPROTO_IPV6]].pr_pfh);
568 #  endif
569 	if (error) {
570 		SPL_X(s);
571 		IPFERROR(130012);
572 		return error;
573 	}
574 # endif
575 #endif
576 	SPL_X(s);
577 
578 #if (__NetBSD_Version__ >= 499005500)
579 	for (i = 0; i < IPL_LOGSIZE; i++)
580 		seldestroy(&ipfmain.ipf_selwait[i]);
581 #endif
582 
583 	ipf_fini_all(softc);
584 
585 	return 0;
586 }
587 
588 
589 /*
590  * Filter ioctl interface.
591  */
592 int
593 ipfioctl(dev_t dev, u_long cmd,
594 #if  (__NetBSD_Version__ >= 499001000)
595 	void *data,
596 #else
597 	caddr_t data,
598 #endif
599 	int mode
600 #if (NetBSD >= 199511)
601 # if  (__NetBSD_Version__ >= 399001400)
602 	, struct lwp *p
603 #   if (__NetBSD_Version__ >= 399002000)
604 #     define	UID(l)	kauth_cred_getuid((l)->l_cred)
605 #  else
606 #     define	UID(l)	((l)->l_proc->p_cred->p_ruid)
607 #  endif
608 # else
609 	, struct proc *p
610 #  define	UID(p)	((p)->p_cred->p_ruid)
611 # endif
612 #endif
613 )
614 {
615 	int error = 0, unit = 0;
616 	SPL_INT(s);
617 
618 #if (__NetBSD_Version__ >= 399002000)
619 	if ((mode & FWRITE) &&
620 	    kauth_authorize_network(p->l_cred, KAUTH_NETWORK_FIREWALL,
621 				    KAUTH_REQ_NETWORK_FIREWALL_FW, NULL,
622 				    NULL, NULL)) {
623 		ipfmain.ipf_interror = 130005;
624 		return EPERM;
625 	}
626 #else
627 	if ((securelevel >= 2) && (mode & FWRITE)) {
628 		ipfmain.ipf_interror = 130001;
629 		return EPERM;
630 	}
631 #endif
632 
633   	unit = GET_MINOR(dev);
634   	if ((IPL_LOGMAX < unit) || (unit < 0)) {
635 		ipfmain.ipf_interror = 130002;
636 		return ENXIO;
637 	}
638 
639 	if (ipfmain.ipf_running <= 0) {
640 		if (unit != IPL_LOGIPF && cmd != SIOCIPFINTERROR) {
641 			ipfmain.ipf_interror = 130003;
642 			return EIO;
643 		}
644 		if (cmd != SIOCIPFGETNEXT && cmd != SIOCIPFGET &&
645 		    cmd != SIOCIPFSET && cmd != SIOCFRENB &&
646 		    cmd != SIOCGETFS && cmd != SIOCGETFF &&
647 		    cmd != SIOCIPFINTERROR) {
648 			ipfmain.ipf_interror = 130004;
649 			return EIO;
650 		}
651 	}
652 
653 	SPL_NET(s);
654 
655 	error = ipf_ioctlswitch(&ipfmain, unit, data, cmd, mode, UID(p), p);
656 	if (error != -1) {
657 		SPL_X(s);
658 		return error;
659 	}
660 
661 	SPL_X(s);
662 	return error;
663 }
664 
665 
666 /*
667  * ipf_send_reset - this could conceivably be a call to tcp_respond(), but that
668  * requires a large amount of setting up and isn't any more efficient.
669  */
670 int
671 ipf_send_reset(fr_info_t *fin)
672 {
673 	struct tcphdr *tcp, *tcp2;
674 	int tlen = 0, hlen;
675 	struct mbuf *m;
676 #ifdef USE_INET6
677 	ip6_t *ip6;
678 #endif
679 	ip_t *ip;
680 
681 	tcp = fin->fin_dp;
682 	if (tcp->th_flags & TH_RST)
683 		return -1;		/* feedback loop */
684 
685 	if (ipf_checkl4sum(fin) == -1)
686 		return -1;
687 
688 	tlen = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
689 			((tcp->th_flags & TH_SYN) ? 1 : 0) +
690 			((tcp->th_flags & TH_FIN) ? 1 : 0);
691 
692 #ifdef USE_INET6
693 	hlen = (fin->fin_v == 6) ? sizeof(ip6_t) : sizeof(ip_t);
694 #else
695 	hlen = sizeof(ip_t);
696 #endif
697 #ifdef MGETHDR
698 	MGETHDR(m, M_DONTWAIT, MT_HEADER);
699 #else
700 	MGET(m, M_DONTWAIT, MT_HEADER);
701 #endif
702 	if (m == NULL)
703 		return -1;
704 	if (sizeof(*tcp2) + hlen > MHLEN) {
705 		MCLGET(m, M_DONTWAIT);
706 		if (m == NULL)
707 			return -1;
708 		if ((m->m_flags & M_EXT) == 0) {
709 			FREE_MB_T(m);
710 			return -1;
711 		}
712 	}
713 
714 	m->m_len = sizeof(*tcp2) + hlen;
715 	m->m_data += max_linkhdr;
716 	m->m_pkthdr.len = m->m_len;
717 	m->m_pkthdr.rcvif = (struct ifnet *)0;
718 	ip = mtod(m, struct ip *);
719 	bzero((char *)ip, hlen);
720 #ifdef USE_INET6
721 	ip6 = (ip6_t *)ip;
722 #endif
723 	bzero((char *)ip, sizeof(*tcp2) + hlen);
724 	tcp2 = (struct tcphdr *)((char *)ip + hlen);
725 	tcp2->th_sport = tcp->th_dport;
726 	tcp2->th_dport = tcp->th_sport;
727 
728 	if (tcp->th_flags & TH_ACK) {
729 		tcp2->th_seq = tcp->th_ack;
730 		tcp2->th_flags = TH_RST;
731 		tcp2->th_ack = 0;
732 	} else {
733 		tcp2->th_seq = 0;
734 		tcp2->th_ack = ntohl(tcp->th_seq);
735 		tcp2->th_ack += tlen;
736 		tcp2->th_ack = htonl(tcp2->th_ack);
737 		tcp2->th_flags = TH_RST|TH_ACK;
738 	}
739 	tcp2->th_x2 = 0;
740 	TCP_OFF_A(tcp2, sizeof(*tcp2) >> 2);
741 	tcp2->th_win = tcp->th_win;
742 	tcp2->th_sum = 0;
743 	tcp2->th_urp = 0;
744 
745 #ifdef USE_INET6
746 	if (fin->fin_v == 6) {
747 		ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
748 		ip6->ip6_plen = htons(sizeof(struct tcphdr));
749 		ip6->ip6_nxt = IPPROTO_TCP;
750 		ip6->ip6_hlim = 0;
751 		ip6->ip6_src = fin->fin_dst6.in6;
752 		ip6->ip6_dst = fin->fin_src6.in6;
753 		tcp2->th_sum = in6_cksum(m, IPPROTO_TCP,
754 					 sizeof(*ip6), sizeof(*tcp2));
755 		return ipf_send_ip(fin, m);
756 	}
757 #endif
758 #ifdef INET
759 	ip->ip_p = IPPROTO_TCP;
760 	ip->ip_len = htons(sizeof(struct tcphdr));
761 	ip->ip_src.s_addr = fin->fin_daddr;
762 	ip->ip_dst.s_addr = fin->fin_saddr;
763 	tcp2->th_sum = in_cksum(m, hlen + sizeof(*tcp2));
764 	ip->ip_len = hlen + sizeof(*tcp2);
765 	return ipf_send_ip(fin, m);
766 #else
767 	return 0;
768 #endif
769 }
770 
771 
772 /*
773  * Expects ip_len to be in host byte order when called.
774  */
775 static int
776 ipf_send_ip(fr_info_t *fin, mb_t *m)
777 {
778 	fr_info_t fnew;
779 #ifdef INET
780 	ip_t *oip;
781 #endif
782 	ip_t *ip;
783 	int hlen;
784 
785 	ip = mtod(m, ip_t *);
786 	bzero((char *)&fnew, sizeof(fnew));
787 	fnew.fin_main_soft = fin->fin_main_soft;
788 
789 	IP_V_A(ip, fin->fin_v);
790 	switch (fin->fin_v)
791 	{
792 #ifdef INET
793 	case 4 :
794 		oip = fin->fin_ip;
795 		hlen = sizeof(*oip);
796 		fnew.fin_v = 4;
797 		fnew.fin_p = ip->ip_p;
798 		fnew.fin_plen = ntohs(ip->ip_len);
799 		HTONS(ip->ip_len);
800 		IP_HL_A(ip, sizeof(*oip) >> 2);
801 		ip->ip_tos = oip->ip_tos;
802 		ip->ip_id = ipf_nextipid(fin);
803 		ip->ip_off = htons(ip_mtudisc ? IP_DF : 0);
804 		ip->ip_ttl = ip_defttl;
805 		ip->ip_sum = 0;
806 		break;
807 #endif
808 #ifdef USE_INET6
809 	case 6 :
810 	{
811 		ip6_t *ip6 = (ip6_t *)ip;
812 
813 		ip6->ip6_vfc = 0x60;
814 		ip6->ip6_hlim = IPDEFTTL;
815 
816 		hlen = sizeof(*ip6);
817 		fnew.fin_p = ip6->ip6_nxt;
818 		fnew.fin_v = 6;
819 		fnew.fin_plen = ntohs(ip6->ip6_plen) + hlen;
820 		break;
821 	}
822 #endif
823 	default :
824 		return EINVAL;
825 	}
826 #ifdef KAME_IPSEC
827 	m->m_pkthdr.rcvif = NULL;
828 #endif
829 
830 	fnew.fin_ifp = fin->fin_ifp;
831 	fnew.fin_flx = FI_NOCKSUM;
832 	fnew.fin_m = m;
833 	fnew.fin_ip = ip;
834 	fnew.fin_mp = &m;
835 	fnew.fin_hlen = hlen;
836 	fnew.fin_dp = (char *)ip + hlen;
837 	(void) ipf_makefrip(hlen, ip, &fnew);
838 
839 	return ipf_fastroute(m, &m, &fnew, NULL);
840 }
841 
842 
843 int
844 ipf_send_icmp_err(int type, fr_info_t *fin, int dst)
845 {
846 	int err, hlen, xtra, iclen, ohlen, avail;
847 	struct in_addr dst4;
848 	struct icmp *icmp;
849 	struct mbuf *m;
850 	i6addr_t dst6;
851 	void *ifp;
852 #ifdef USE_INET6
853 	int code;
854 	ip6_t *ip6;
855 #endif
856 	ip_t *ip, *ip2;
857 
858 	if ((type < 0) || (type > ICMP_MAXTYPE))
859 		return -1;
860 
861 #ifdef USE_INET6
862 	code = fin->fin_icode;
863 	if ((code < 0) || (code >= sizeof(icmptoicmp6unreach)/sizeof(int)))
864 		return -1;
865 #endif
866 
867 	if (ipf_checkl4sum(fin) == -1)
868 		return -1;
869 #ifdef MGETHDR
870 	MGETHDR(m, M_DONTWAIT, MT_HEADER);
871 #else
872 	MGET(m, M_DONTWAIT, MT_HEADER);
873 #endif
874 	if (m == NULL)
875 		return -1;
876 	avail = MHLEN;
877 
878 	xtra = 0;
879 	hlen = 0;
880 	ohlen = 0;
881 	dst4.s_addr = 0;
882 	ifp = fin->fin_ifp;
883 	if (fin->fin_v == 4) {
884 		if ((fin->fin_p == IPPROTO_ICMP) && !(fin->fin_flx & FI_SHORT))
885 			switch (ntohs(fin->fin_data[0]) >> 8)
886 			{
887 			case ICMP_ECHO :
888 			case ICMP_TSTAMP :
889 			case ICMP_IREQ :
890 			case ICMP_MASKREQ :
891 				break;
892 			default :
893 				FREE_MB_T(m);
894 				return 0;
895 			}
896 
897 		if (dst == 0) {
898 			if (ipf_ifpaddr(&ipfmain, 4, FRI_NORMAL, ifp,
899 				       &dst6, NULL) == -1) {
900 				FREE_MB_T(m);
901 				return -1;
902 			}
903 			dst4 = dst6.in4;
904 		} else
905 			dst4.s_addr = fin->fin_daddr;
906 
907 		hlen = sizeof(ip_t);
908 		ohlen = fin->fin_hlen;
909 		iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
910 		if (fin->fin_hlen < fin->fin_plen)
911 			xtra = MIN(fin->fin_dlen, 8);
912 		else
913 			xtra = 0;
914 	}
915 
916 #ifdef USE_INET6
917 	else if (fin->fin_v == 6) {
918 		hlen = sizeof(ip6_t);
919 		ohlen = sizeof(ip6_t);
920 		iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
921 		type = icmptoicmp6types[type];
922 		if (type == ICMP6_DST_UNREACH)
923 			code = icmptoicmp6unreach[code];
924 
925 		if (iclen + max_linkhdr + fin->fin_plen > avail) {
926 			MCLGET(m, M_DONTWAIT);
927 			if (m == NULL)
928 				return -1;
929 			if ((m->m_flags & M_EXT) == 0) {
930 				FREE_MB_T(m);
931 				return -1;
932 			}
933 			avail = MCLBYTES;
934 		}
935 		xtra = MIN(fin->fin_plen, avail - iclen - max_linkhdr);
936 		xtra = MIN(xtra, IPV6_MMTU - iclen);
937 		if (dst == 0) {
938 			if (ipf_ifpaddr(&ipfmain, 6, FRI_NORMAL, ifp,
939 				       &dst6, NULL) == -1) {
940 				FREE_MB_T(m);
941 				return -1;
942 			}
943 		} else
944 			dst6 = fin->fin_dst6;
945 	}
946 #endif
947 	else {
948 		FREE_MB_T(m);
949 		return -1;
950 	}
951 
952 	avail -= (max_linkhdr + iclen);
953 	if (avail < 0) {
954 		FREE_MB_T(m);
955 		return -1;
956 	}
957 	if (xtra > avail)
958 		xtra = avail;
959 	iclen += xtra;
960 	m->m_data += max_linkhdr;
961 	m->m_pkthdr.rcvif = (struct ifnet *)0;
962 	m->m_pkthdr.len = iclen;
963 	m->m_len = iclen;
964 	ip = mtod(m, ip_t *);
965 	icmp = (struct icmp *)((char *)ip + hlen);
966 	ip2 = (ip_t *)&icmp->icmp_ip;
967 
968 	icmp->icmp_type = type;
969 	icmp->icmp_code = fin->fin_icode;
970 	icmp->icmp_cksum = 0;
971 #ifdef icmp_nextmtu
972 	if (type == ICMP_UNREACH && fin->fin_icode == ICMP_UNREACH_NEEDFRAG) {
973 		if (fin->fin_mtu != 0) {
974 			icmp->icmp_nextmtu = htons(fin->fin_mtu);
975 
976 		} else if (ifp != NULL) {
977 			icmp->icmp_nextmtu = htons(GETIFMTU_4(ifp));
978 
979 		} else {	/* make up a number... */
980 			icmp->icmp_nextmtu = htons(fin->fin_plen - 20);
981 		}
982 	}
983 #endif
984 
985 	bcopy((char *)fin->fin_ip, (char *)ip2, ohlen);
986 
987 #if defined(M_CSUM_IPv4)
988 	/*
989 	 * Clear any in-bound checksum flags for this packet.
990 	 */
991 	m->m_pkthdr.csuminfo = 0;
992 #endif /* __NetBSD__ && M_CSUM_IPv4 */
993 
994 #ifdef USE_INET6
995 	ip6 = (ip6_t *)ip;
996 	if (fin->fin_v == 6) {
997 		ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
998 		ip6->ip6_plen = htons(iclen - hlen);
999 		ip6->ip6_nxt = IPPROTO_ICMPV6;
1000 		ip6->ip6_hlim = 0;
1001 		ip6->ip6_src = dst6.in6;
1002 		ip6->ip6_dst = fin->fin_src6.in6;
1003 		if (xtra > 0)
1004 			bcopy((char *)fin->fin_ip + ohlen,
1005 			      (char *)&icmp->icmp_ip + ohlen, xtra);
1006 		icmp->icmp_cksum = in6_cksum(m, IPPROTO_ICMPV6,
1007 					     sizeof(*ip6), iclen - hlen);
1008 	} else
1009 #endif
1010 	{
1011 		ip->ip_p = IPPROTO_ICMP;
1012 		ip->ip_src.s_addr = dst4.s_addr;
1013 		ip->ip_dst.s_addr = fin->fin_saddr;
1014 
1015 		if (xtra > 0)
1016 			bcopy((char *)fin->fin_ip + ohlen,
1017 			      (char *)&icmp->icmp_ip + ohlen, xtra);
1018 		icmp->icmp_cksum = ipf_cksum((u_short *)icmp,
1019 					     sizeof(*icmp) + 8);
1020 		ip->ip_len = iclen;
1021 		ip->ip_p = IPPROTO_ICMP;
1022 	}
1023 	err = ipf_send_ip(fin, m);
1024 	return err;
1025 }
1026 
1027 
1028 /*
1029  * m0 - pointer to mbuf where the IP packet starts
1030  * mpp - pointer to the mbuf pointer that is the start of the mbuf chain
1031  */
1032 int
1033 ipf_fastroute(mb_t *m0, mb_t **mpp, fr_info_t *fin, frdest_t *fdp)
1034 {
1035 	register struct ip *ip, *mhip;
1036 	register struct mbuf *m = *mpp;
1037 	register struct route *ro;
1038 	int len, off, error = 0, hlen, code;
1039 	struct ifnet *ifp, *sifp;
1040 	ipf_main_softc_t *softc;
1041 #if __NetBSD_Version__ >= 499001100
1042 	union {
1043 		struct sockaddr         dst;
1044 		struct sockaddr_in      dst4;
1045 	} u;
1046 #else
1047 	struct sockaddr_in *dst4;
1048 #endif
1049 	struct sockaddr *dst;
1050 	u_short ip_off, ip_len;
1051 	struct route iproute;
1052 	struct rtentry *rt;
1053 	frdest_t node;
1054 	frentry_t *fr;
1055 
1056 	if (fin->fin_v == 6) {
1057 #ifdef USE_INET6
1058 		error = ipf_fastroute6(m0, mpp, fin, fdp);
1059 #else
1060 		error = EPROTONOSUPPORT;
1061 #endif
1062 		if ((error != 0) && (*mpp != NULL))
1063 			FREE_MB_T(*mpp);
1064 		return error;
1065 	}
1066 #ifndef INET
1067 	FREE_MB_T(*mpp);
1068 	return EPROTONOSUPPORT;
1069 #else
1070 
1071 	hlen = fin->fin_hlen;
1072 	ip = mtod(m0, struct ip *);
1073 	softc = fin->fin_main_soft;
1074 	rt = NULL;
1075 	ifp = NULL;
1076 
1077 # if defined(M_CSUM_IPv4)
1078 	/*
1079 	 * Clear any in-bound checksum flags for this packet.
1080 	 */
1081 	m0->m_pkthdr.csuminfo = 0;
1082 # endif /* __NetBSD__ && M_CSUM_IPv4 */
1083 
1084 	/*
1085 	 * Route packet.
1086 	 */
1087 	ro = &iproute;
1088 	memset(ro, 0, sizeof(*ro));
1089 	fr = fin->fin_fr;
1090 
1091 	if ((fr != NULL) && !(fr->fr_flags & FR_KEEPSTATE) && (fdp != NULL) &&
1092 	    (fdp->fd_type == FRD_DSTLIST)) {
1093 		if (ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, &node) == 0)
1094 			fdp = &node;
1095 	}
1096 	if (fdp != NULL)
1097 		ifp = fdp->fd_ptr;
1098 	else
1099 		ifp = fin->fin_ifp;
1100 
1101 	if ((ifp == NULL) && ((fr == NULL) || !(fr->fr_flags & FR_FASTROUTE))) {
1102 		error = -2;
1103 		goto bad;
1104 	}
1105 
1106 # if __NetBSD_Version__ >= 499001100
1107 	if ((fdp != NULL) && (fdp->fd_ip.s_addr != 0))
1108 		sockaddr_in_init(&u.dst4, &fdp->fd_ip, 0);
1109 	else
1110 		sockaddr_in_init(&u.dst4, &ip->ip_dst, 0);
1111 	dst = &u.dst;
1112 	rtcache_setdst(ro, dst);
1113 	rt = rtcache_init(ro);
1114 # else
1115 	dst4 = (struct sockaddr_in *)&ro->ro_dst;
1116 	dst = (struct sockaddr *)dst4;
1117 	dst4->sin_family = AF_INET;
1118 	dst4->sin_addr = ip->ip_dst;
1119 
1120 	if ((fdp != NULL) && (fdp->fd_ip.s_addr != 0))
1121 		dst4->sin_addr = fdp->fd_ip;
1122 
1123 	dst4->sin_len = sizeof(*dst);
1124 	rtalloc(ro);
1125 	rt = ro->ro_rt;
1126 # endif
1127 	if ((ifp == NULL) && (rt != NULL))
1128 		ifp = rt->rt_ifp;
1129 	if ((rt == NULL) || (ifp == NULL)) {
1130 #ifdef INET
1131 		if (in_localaddr(ip->ip_dst))
1132 			error = EHOSTUNREACH;
1133 		else
1134 #endif
1135 			error = ENETUNREACH;
1136 		goto bad;
1137 	}
1138 
1139 
1140 	if (rt->rt_flags & RTF_GATEWAY)
1141 		dst = rt->rt_gateway;
1142 
1143 	rt->rt_use++;
1144 
1145 	/*
1146 	 * For input packets which are being "fastrouted", they won't
1147 	 * go back through output filtering and miss their chance to get
1148 	 * NAT'd and counted.  Duplicated packets aren't considered to be
1149 	 * part of the normal packet stream, so do not NAT them or pass
1150 	 * them through stateful checking, etc.
1151 	 */
1152 	if ((fdp != &fr->fr_dif) && (fin->fin_out == 0)) {
1153 		sifp = fin->fin_ifp;
1154 		fin->fin_ifp = ifp;
1155 		fin->fin_out = 1;
1156 		(void) ipf_acctpkt(fin, NULL);
1157 		fin->fin_fr = NULL;
1158 		if (!fr || !(fr->fr_flags & FR_RETMASK)) {
1159 			u_32_t pass;
1160 
1161 			(void) ipf_state_check(fin, &pass);
1162 		}
1163 
1164 		switch (ipf_nat_checkout(fin, NULL))
1165 		{
1166 		case 0 :
1167 			break;
1168 		case 1 :
1169 			ip->ip_sum = 0;
1170 			break;
1171 		case -1 :
1172 			error = -1;
1173 			goto bad;
1174 			break;
1175 		}
1176 
1177 		fin->fin_ifp = sifp;
1178 		fin->fin_out = 0;
1179 	} else
1180 		ip->ip_sum = 0;
1181 	/*
1182 	 * If small enough for interface, can just send directly.
1183 	 */
1184 	m->m_pkthdr.rcvif = ifp;
1185 
1186 	ip_len = ntohs(ip->ip_len);
1187 	if (ip_len <= ifp->if_mtu) {
1188 # if defined(M_CSUM_IPv4)
1189 #  if (__NetBSD_Version__ >= 105009999)
1190 		if (ifp->if_csum_flags_tx & M_CSUM_IPv4)
1191 			m->m_pkthdr.csuminfo |= M_CSUM_IPv4;
1192 #  else
1193 		if (ifp->if_capabilities & IFCAP_CSUM_IPv4)
1194 			m->m_pkthdr.csuminfo |= M_CSUM_IPv4;
1195 #  endif /* (__NetBSD_Version__ >= 105009999) */
1196 		else if (ip->ip_sum == 0)
1197 			ip->ip_sum = in_cksum(m, hlen);
1198 # else
1199 		if (!ip->ip_sum)
1200 			ip->ip_sum = in_cksum(m, hlen);
1201 # endif /* M_CSUM_IPv4 */
1202 
1203 		error = (*ifp->if_output)(ifp, m, dst, rt);
1204 		goto done;
1205 	}
1206 
1207 	/*
1208 	 * Too large for interface; fragment if possible.
1209 	 * Must be able to put at least 8 bytes per fragment.
1210 	 */
1211 	ip_off = ntohs(ip->ip_off);
1212 	if (ip_off & IP_DF) {
1213 		error = EMSGSIZE;
1214 		goto bad;
1215 	}
1216 	len = (ifp->if_mtu - hlen) &~ 7;
1217 	if (len < 8) {
1218 		error = EMSGSIZE;
1219 		goto bad;
1220 	}
1221 
1222     {
1223 	int mhlen, firstlen = len;
1224 	struct mbuf **mnext = &m->m_act;
1225 
1226 	/*
1227 	 * Loop through length of segment after first fragment,
1228 	 * make new header and copy data of each part and link onto chain.
1229 	 */
1230 	m0 = m;
1231 	mhlen = sizeof (struct ip);
1232 	for (off = hlen + len; off < ip_len; off += len) {
1233 # ifdef MGETHDR
1234 		MGETHDR(m, M_DONTWAIT, MT_HEADER);
1235 # else
1236 		MGET(m, M_DONTWAIT, MT_HEADER);
1237 # endif
1238 		if (m == 0) {
1239 			m = m0;
1240 			error = ENOBUFS;
1241 			goto bad;
1242 		}
1243 		m->m_data += max_linkhdr;
1244 		mhip = mtod(m, struct ip *);
1245 		bcopy((char *)ip, (char *)mhip, sizeof(*ip));
1246 #ifdef INET
1247 		if (hlen > sizeof (struct ip)) {
1248 			mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
1249 			IP_HL_A(mhip, mhlen >> 2);
1250 		}
1251 #endif
1252 		m->m_len = mhlen;
1253 		mhip->ip_off = ((off - hlen) >> 3) + ip_off;
1254 		if (off + len >= ip_len)
1255 			len = ip_len - off;
1256 		else
1257 			mhip->ip_off |= IP_MF;
1258 		mhip->ip_len = htons((u_short)(len + mhlen));
1259 		m->m_next = m_copy(m0, off, len);
1260 		if (m->m_next == 0) {
1261 			error = ENOBUFS;	/* ??? */
1262 			goto sendorfree;
1263 		}
1264 		m->m_pkthdr.len = mhlen + len;
1265 		m->m_pkthdr.rcvif = NULL;
1266 		mhip->ip_off = htons((u_short)mhip->ip_off);
1267 		mhip->ip_sum = 0;
1268 #ifdef INET
1269 		mhip->ip_sum = in_cksum(m, mhlen);
1270 #endif
1271 		*mnext = m;
1272 		mnext = &m->m_act;
1273 	}
1274 	/*
1275 	 * Update first fragment by trimming what's been copied out
1276 	 * and updating header, then send each fragment (in order).
1277 	 */
1278 	m_adj(m0, hlen + firstlen - ip_len);
1279 	ip->ip_len = htons((u_short)(hlen + firstlen));
1280 	ip->ip_off = htons((u_short)IP_MF);
1281 	ip->ip_sum = 0;
1282 #ifdef INET
1283 	ip->ip_sum = in_cksum(m0, hlen);
1284 #endif
1285 sendorfree:
1286 	for (m = m0; m; m = m0) {
1287 		m0 = m->m_act;
1288 		m->m_act = 0;
1289 		if (error == 0) {
1290 			error = (*ifp->if_output)(ifp, m, dst, rt);
1291 		} else {
1292 			FREE_MB_T(m);
1293 		}
1294 	}
1295     }
1296 done:
1297 	if (!error)
1298 		softc->ipf_frouteok[0]++;
1299 	else
1300 		softc->ipf_frouteok[1]++;
1301 
1302 # if __NetBSD_Version__ >= 499001100
1303 	rtcache_free(ro);
1304 # else
1305 	if (rt) {
1306 		RTFREE(rt);
1307 	}
1308 # endif
1309 	return error;
1310 bad:
1311 	if (error == EMSGSIZE) {
1312 		sifp = fin->fin_ifp;
1313 		code = fin->fin_icode;
1314 		fin->fin_icode = ICMP_UNREACH_NEEDFRAG;
1315 		fin->fin_ifp = ifp;
1316 		(void) ipf_send_icmp_err(ICMP_UNREACH, fin, 1);
1317 		fin->fin_ifp = sifp;
1318 		fin->fin_icode = code;
1319 	}
1320 	FREE_MB_T(m);
1321 	goto done;
1322 #endif /* INET */
1323 }
1324 
1325 
1326 #if defined(USE_INET6)
1327 /*
1328  * This is the IPv6 specific fastroute code.  It doesn't clean up the mbuf's
1329  * or ensure that it is an IPv6 packet that is being forwarded, those are
1330  * expected to be done by the called (ipf_fastroute).
1331  */
1332 static int
1333 ipf_fastroute6(struct mbuf *m0, struct mbuf **mpp, fr_info_t *fin,
1334     frdest_t *fdp)
1335 {
1336 # if __NetBSD_Version__ >= 499001100
1337 	struct route ip6route;
1338 	const struct sockaddr *dst;
1339 	union {
1340 		struct sockaddr         dst;
1341 		struct sockaddr_in6     dst6;
1342 	} u;
1343 	struct route *ro;
1344 # else
1345 	struct route_in6 ip6route;
1346 	struct sockaddr_in6 *dst6;
1347 	struct route_in6 *ro;
1348 # endif
1349 	struct rtentry *rt;
1350 	struct ifnet *ifp;
1351 	u_long mtu;
1352 	int error;
1353 
1354 	error = 0;
1355 	ro = &ip6route;
1356 
1357 	if (fdp != NULL)
1358 		ifp = fdp->fd_ptr;
1359 	else
1360 		ifp = fin->fin_ifp;
1361 	memset(ro, 0, sizeof(*ro));
1362 # if __NetBSD_Version__ >= 499001100
1363 	if (fdp != NULL && IP6_NOTZERO(&fdp->fd_ip6))
1364 		sockaddr_in6_init(&u.dst6, &fdp->fd_ip6.in6, 0, 0, 0);
1365 	else
1366 		sockaddr_in6_init(&u.dst6, &fin->fin_fi.fi_dst.in6, 0, 0, 0);
1367 	dst = &u.dst;
1368 	rtcache_setdst(ro, dst);
1369 
1370 	rt = rtcache_init(ro);
1371 	if ((ifp == NULL) && (rt != NULL))
1372 		ifp = rt->rt_ifp;
1373 # else
1374 	dst6 = (struct sockaddr_in6 *)&ro->ro_dst;
1375 	dst6->sin6_family = AF_INET6;
1376 	dst6->sin6_len = sizeof(struct sockaddr_in6);
1377 	dst6->sin6_addr = fin->fin_fi.fi_dst.in6;
1378 
1379 	if (fdp != NULL) {
1380 		if (IP6_NOTZERO(&fdp->fd_ip6))
1381 			dst6->sin6_addr = fdp->fd_ip6.in6;
1382 	}
1383 
1384 	rtalloc((struct route *)ro);
1385 
1386 	if ((ifp == NULL) && (ro->ro_rt != NULL))
1387 		ifp = ro->ro_rt->rt_ifp;
1388 	rt = ro->ro_rt;
1389 # endif
1390 	if ((rt == NULL) || (ifp == NULL)) {
1391 
1392 		error = EHOSTUNREACH;
1393 		goto bad;
1394 	}
1395 
1396 	/* KAME */
1397 # if __NetBSD_Version__ >= 499001100
1398 	if (IN6_IS_ADDR_LINKLOCAL(&u.dst6.sin6_addr))
1399 		u.dst6.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
1400 # else
1401 	if (IN6_IS_ADDR_LINKLOCAL(&dst6->sin6_addr))
1402 		dst6->sin6_addr.s6_addr16[1] = htons(ifp->if_index);
1403 # endif
1404 
1405 	{
1406 # if (__NetBSD_Version__ >= 106010000) && !defined(IN6_LINKMTU)
1407 		struct in6_ifextra *ife;
1408 # endif
1409 		if (rt->rt_flags & RTF_GATEWAY)
1410 # if __NetBSD_Version__ >= 499001100
1411 			dst = rt->rt_gateway;
1412 # else
1413 			dst6 = (struct sockaddr_in6 *)rt->rt_gateway;
1414 # endif
1415 		rt->rt_use++;
1416 
1417 		/* Determine path MTU. */
1418 # if (__NetBSD_Version__ <= 106009999)
1419 		mtu = nd_ifinfo[ifp->if_index].linkmtu;
1420 # else
1421 #  ifdef IN6_LINKMTU
1422 		mtu = IN6_LINKMTU(ifp);
1423 #  else
1424 		ife = (struct in6_ifextra *)(ifp)->if_afdata[AF_INET6];
1425 		mtu = ife->nd_ifinfo[ifp->if_index].linkmtu;
1426 #  endif
1427 # endif
1428 		if ((error == 0) && (m0->m_pkthdr.len <= mtu)) {
1429 # if __NetBSD_Version__ >= 499001100
1430 			error = nd6_output(ifp, ifp, m0, satocsin6(dst), rt);
1431 # else
1432 			error = nd6_output(ifp, ifp, m0, dst6, rt);
1433 # endif
1434 		} else {
1435 			error = EMSGSIZE;
1436 		}
1437 	}
1438 bad:
1439 # if __NetBSD_Version__ >= 499001100
1440 	rtcache_free(ro);
1441 # else
1442 	if (ro->ro_rt != NULL) {
1443 		RTFREE(((struct route *)ro)->ro_rt);
1444 	}
1445 # endif
1446 	return error;
1447 }
1448 #endif	/* INET6 */
1449 
1450 
1451 int
1452 ipf_verifysrc(fr_info_t *fin)
1453 {
1454 #if __NetBSD_Version__ >= 499001100
1455 	union {
1456 		struct sockaddr         dst;
1457 		struct sockaddr_in      dst4;
1458 	} u;
1459 	struct rtentry *rt;
1460 #else
1461 	struct sockaddr_in *dst;
1462 #endif
1463 	struct route iproute;
1464 	int rc;
1465 
1466 #if __NetBSD_Version__ >= 499001100
1467 	sockaddr_in_init(&u.dst4, &fin->fin_src, 0);
1468 	rtcache_setdst(&iproute, &u.dst);
1469 	rt = rtcache_init(&iproute);
1470 	if (rt == NULL)
1471 		rc = 0;
1472 	else
1473 		rc = (fin->fin_ifp == rt->rt_ifp);
1474 	rtcache_free(&iproute);
1475 #else
1476 	dst = (struct sockaddr_in *)&iproute.ro_dst;
1477 	dst->sin_len = sizeof(*dst);
1478 	dst->sin_family = AF_INET;
1479 	dst->sin_addr = fin->fin_src;
1480 	rtalloc(&iproute);
1481 	if (iproute.ro_rt == NULL)
1482 		return 0;
1483 	rc = (fin->fin_ifp == iproute.ro_rt->rt_ifp);
1484 	RTFREE(iproute.ro_rt);
1485 #endif
1486 	return rc;
1487 }
1488 
1489 
1490 /*
1491  * return the first IP Address associated with an interface
1492  */
1493 int
1494 ipf_ifpaddr(ipf_main_softc_t *softc, int v, int atype, void *ifptr,
1495     i6addr_t *inp, i6addr_t *inpmask)
1496 {
1497 #ifdef USE_INET6
1498 	struct in6_addr *inp6 = NULL;
1499 #endif
1500 	struct sockaddr *sock, *mask;
1501 	struct sockaddr_in *sin;
1502 	struct ifaddr *ifa;
1503 	struct ifnet *ifp;
1504 
1505 	if ((ifptr == NULL) || (ifptr == (void *)-1))
1506 		return -1;
1507 
1508 	ifp = ifptr;
1509 	mask = NULL;
1510 
1511 	if (v == 4)
1512 		inp->in4.s_addr = 0;
1513 #ifdef USE_INET6
1514 	else if (v == 6)
1515 		bzero((char *)inp, sizeof(*inp));
1516 #endif
1517 
1518 	ifa = IFADDR_FIRST(ifp);
1519 	sock = ifa ? ifa->ifa_addr : NULL;
1520 	while (sock != NULL && ifa != NULL) {
1521 		sin = (struct sockaddr_in *)sock;
1522 		if ((v == 4) && (sin->sin_family == AF_INET))
1523 			break;
1524 #ifdef USE_INET6
1525 		if ((v == 6) && (sin->sin_family == AF_INET6)) {
1526 			inp6 = &((struct sockaddr_in6 *)sin)->sin6_addr;
1527 			if (!IN6_IS_ADDR_LINKLOCAL(inp6) &&
1528 			    !IN6_IS_ADDR_LOOPBACK(inp6))
1529 				break;
1530 		}
1531 #endif
1532 		ifa = IFADDR_NEXT(ifa);
1533 		if (ifa != NULL)
1534 			sock = ifa->ifa_addr;
1535 	}
1536 	if (ifa == NULL || sock == NULL)
1537 		return -1;
1538 
1539 	mask = ifa->ifa_netmask;
1540 	if (atype == FRI_BROADCAST)
1541 		sock = ifa->ifa_broadaddr;
1542 	else if (atype == FRI_PEERADDR)
1543 		sock = ifa->ifa_dstaddr;
1544 
1545 #ifdef USE_INET6
1546 	if (v == 6)
1547 		return ipf_ifpfillv6addr(atype, (struct sockaddr_in6 *)sock,
1548 					(struct sockaddr_in6 *)mask,
1549 					inp, inpmask);
1550 #endif
1551 	return ipf_ifpfillv4addr(atype, (struct sockaddr_in *)sock,
1552 				(struct sockaddr_in *)mask,
1553 				&inp->in4, &inpmask->in4);
1554 }
1555 
1556 
1557 u_32_t
1558 ipf_newisn(fr_info_t *fin)
1559 {
1560 #if __NetBSD_Version__ >= 105190000	/* 1.5T */
1561 	size_t asz;
1562 
1563 	if (fin->fin_v == 4)
1564 		asz = sizeof(struct in_addr);
1565 	else if (fin->fin_v == 6)
1566 		asz = sizeof(fin->fin_src);
1567 	else	/* XXX: no way to return error */
1568 		return 0;
1569 #ifdef INET
1570 	return tcp_new_iss1((void *)&fin->fin_src, (void *)&fin->fin_dst,
1571 			    fin->fin_sport, fin->fin_dport, asz, 0);
1572 #else
1573 	return ENOSYS;
1574 #endif
1575 #else
1576 	static int iss_seq_off = 0;
1577 	u_char hash[16];
1578 	u_32_t newiss;
1579 	MD5_CTX ctx;
1580 
1581 	/*
1582 	 * Compute the base value of the ISS.  It is a hash
1583 	 * of (saddr, sport, daddr, dport, secret).
1584 	 */
1585 	MD5Init(&ctx);
1586 
1587 	MD5Update(&ctx, (u_char *) &fin->fin_fi.fi_src,
1588 		  sizeof(fin->fin_fi.fi_src));
1589 	MD5Update(&ctx, (u_char *) &fin->fin_fi.fi_dst,
1590 		  sizeof(fin->fin_fi.fi_dst));
1591 	MD5Update(&ctx, (u_char *) &fin->fin_dat, sizeof(fin->fin_dat));
1592 
1593 	MD5Update(&ctx, ipf_iss_secret, sizeof(ipf_iss_secret));
1594 
1595 	MD5Final(hash, &ctx);
1596 
1597 	memcpy(&newiss, hash, sizeof(newiss));
1598 
1599 	/*
1600 	 * Now increment our "timer", and add it in to
1601 	 * the computed value.
1602 	 *
1603 	 * XXX Use `addin'?
1604 	 * XXX TCP_ISSINCR too large to use?
1605 	 */
1606 	iss_seq_off += 0x00010000;
1607 	newiss += iss_seq_off;
1608 	return newiss;
1609 #endif
1610 }
1611 
1612 
1613 /* ------------------------------------------------------------------------ */
1614 /* Function:    ipf_nextipid                                                 */
1615 /* Returns:     int - 0 == success, -1 == error (packet should be droppped) */
1616 /* Parameters:  fin(I) - pointer to packet information                      */
1617 /*                                                                          */
1618 /* Returns the next IPv4 ID to use for this packet.                         */
1619 /* ------------------------------------------------------------------------ */
1620 u_short
1621 ipf_nextipid(fr_info_t *fin)
1622 {
1623 #ifdef USE_MUTEXES
1624 	ipf_main_softc_t *softc = fin->fin_main_soft;
1625 #endif
1626 	u_short id;
1627 
1628 	MUTEX_ENTER(&softc->ipf_rw);
1629 	id = ipid++;
1630 	MUTEX_EXIT(&softc->ipf_rw);
1631 
1632 	return id;
1633 }
1634 
1635 
1636 EXTERN_INLINE int
1637 ipf_checkv4sum(fr_info_t *fin)
1638 {
1639 #ifdef M_CSUM_TCP_UDP_BAD
1640 	int manual, pflag, cflags, active;
1641 	mb_t *m;
1642 
1643 	if ((fin->fin_flx & FI_NOCKSUM) != 0)
1644 		return 0;
1645 
1646 	if ((fin->fin_flx & FI_SHORT) != 0)
1647 		return 1;
1648 
1649 	if (fin->fin_cksum != FI_CK_NEEDED)
1650 		return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1651 
1652 	manual = 0;
1653 	m = fin->fin_m;
1654 	if (m == NULL) {
1655 		manual = 1;
1656 		goto skipauto;
1657 	}
1658 
1659 	switch (fin->fin_p)
1660 	{
1661 	case IPPROTO_UDP :
1662 		pflag = M_CSUM_UDPv4;
1663 		break;
1664 	case IPPROTO_TCP :
1665 		pflag = M_CSUM_TCPv4;
1666 		break;
1667 	default :
1668 		pflag = 0;
1669 		manual = 1;
1670 		break;
1671 	}
1672 
1673 	active = ((struct ifnet *)fin->fin_ifp)->if_csum_flags_rx & pflag;
1674 	active |= M_CSUM_TCP_UDP_BAD | M_CSUM_DATA;
1675 	cflags = m->m_pkthdr.csum_flags & active;
1676 
1677 	if (pflag != 0) {
1678 		if (cflags == (pflag | M_CSUM_TCP_UDP_BAD)) {
1679 			fin->fin_flx |= FI_BAD;
1680 			fin->fin_cksum = FI_CK_BAD;
1681 		} else if (cflags == (pflag | M_CSUM_DATA)) {
1682 			if ((m->m_pkthdr.csum_data ^ 0xffff) != 0) {
1683 				fin->fin_flx |= FI_BAD;
1684 				fin->fin_cksum = FI_CK_BAD;
1685 			} else {
1686 				fin->fin_cksum = FI_CK_SUMOK;
1687 			}
1688 		} else if (cflags == pflag) {
1689 			fin->fin_cksum = FI_CK_SUMOK;
1690 		} else {
1691 			manual = 1;
1692 		}
1693 	}
1694 skipauto:
1695 	if (manual != 0) {
1696 		if (ipf_checkl4sum(fin) == -1) {
1697 			fin->fin_flx |= FI_BAD;
1698 			return -1;
1699 		}
1700 	}
1701 #else
1702 	if (ipf_checkl4sum(fin) == -1) {
1703 		fin->fin_flx |= FI_BAD;
1704 		return -1;
1705 	}
1706 #endif
1707 	return 0;
1708 }
1709 
1710 
1711 #ifdef USE_INET6
1712 EXTERN_INLINE int
1713 ipf_checkv6sum(fr_info_t *fin)
1714 {
1715 # ifdef M_CSUM_TCP_UDP_BAD
1716 	int manual, pflag, cflags, active;
1717 	mb_t *m;
1718 
1719 	if ((fin->fin_flx & FI_NOCKSUM) != 0)
1720 		return 0;
1721 
1722 	if ((fin->fin_flx & FI_SHORT) != 0)
1723 		return 1;
1724 
1725 	if (fin->fin_cksum != FI_CK_SUMOK)
1726 		return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1727 
1728 
1729 	manual = 0;
1730 	m = fin->fin_m;
1731 
1732 	switch (fin->fin_p)
1733 	{
1734 	case IPPROTO_UDP :
1735 		pflag = M_CSUM_UDPv6;
1736 		break;
1737 	case IPPROTO_TCP :
1738 		pflag = M_CSUM_TCPv6;
1739 		break;
1740 	default :
1741 		pflag = 0;
1742 		manual = 1;
1743 		break;
1744 	}
1745 
1746 	active = ((struct ifnet *)fin->fin_ifp)->if_csum_flags_rx & pflag;
1747 	active |= M_CSUM_TCP_UDP_BAD | M_CSUM_DATA;
1748 	cflags = m->m_pkthdr.csum_flags & active;
1749 
1750 	if (pflag != 0) {
1751 		if (cflags == (pflag | M_CSUM_TCP_UDP_BAD)) {
1752 			fin->fin_flx |= FI_BAD;
1753 		} else if (cflags == (pflag | M_CSUM_DATA)) {
1754 			if ((m->m_pkthdr.csum_data ^ 0xffff) != 0)
1755 				fin->fin_flx |= FI_BAD;
1756 		} else if (cflags == pflag) {
1757 			;
1758 		} else {
1759 			manual = 1;
1760 		}
1761 	}
1762 	if (manual != 0) {
1763 		if (ipf_checkl4sum(fin) == -1) {
1764 			fin->fin_flx |= FI_BAD;
1765 			return -1;
1766 		}
1767 	}
1768 # else
1769 	if (ipf_checkl4sum(fin) == -1) {
1770 		fin->fin_flx |= FI_BAD;
1771 		return -1;
1772 	}
1773 # endif
1774 	return 0;
1775 }
1776 #endif /* USE_INET6 */
1777 
1778 
1779 size_t
1780 mbufchainlen(struct mbuf *m0)
1781 {
1782 	size_t len;
1783 
1784 	if ((m0->m_flags & M_PKTHDR) != 0) {
1785 		len = m0->m_pkthdr.len;
1786 	} else {
1787 		struct mbuf *m;
1788 
1789 		for (m = m0, len = 0; m != NULL; m = m->m_next)
1790 			len += m->m_len;
1791 	}
1792 	return len;
1793 }
1794 
1795 
1796 /* ------------------------------------------------------------------------ */
1797 /* Function:    ipf_pullup                                                  */
1798 /* Returns:     NULL == pullup failed, else pointer to protocol header      */
1799 /* Parameters:  xmin(I)- pointer to buffer where data packet starts         */
1800 /*              fin(I) - pointer to packet information                      */
1801 /*              len(I) - number of bytes to pullup                          */
1802 /*                                                                          */
1803 /* Attempt to move at least len bytes (from the start of the buffer) into a */
1804 /* single buffer for ease of access.  Operating system native functions are */
1805 /* used to manage buffers - if necessary.  If the entire packet ends up in  */
1806 /* a single buffer, set the FI_COALESCE flag even though ipf_coalesce() has */
1807 /* not been called.  Both fin_ip and fin_dp are updated before exiting _IF_ */
1808 /* and ONLY if the pullup succeeds.                                         */
1809 /*                                                                          */
1810 /* We assume that 'xmin' is a pointer to a buffer that is part of the chain */
1811 /* of buffers that starts at *fin->fin_mp.                                  */
1812 /* ------------------------------------------------------------------------ */
1813 void *
1814 ipf_pullup(mb_t *xmin, fr_info_t *fin, int len)
1815 {
1816 	int dpoff, ipoff;
1817 	mb_t *m = xmin;
1818 	char *ip;
1819 
1820 	if (m == NULL)
1821 		return NULL;
1822 
1823 	ip = (char *)fin->fin_ip;
1824 	if ((fin->fin_flx & FI_COALESCE) != 0)
1825 		return ip;
1826 
1827 	ipoff = fin->fin_ipoff;
1828 	if (fin->fin_dp != NULL)
1829 		dpoff = (char *)fin->fin_dp - (char *)ip;
1830 	else
1831 		dpoff = 0;
1832 
1833 	if (M_LEN(m) < len) {
1834 		mb_t *n = *fin->fin_mp;
1835 		/*
1836 		 * Assume that M_PKTHDR is set and just work with what is left
1837 		 * rather than check..
1838 		 * Should not make any real difference, anyway.
1839 		 */
1840 		if (m != n) {
1841 			/*
1842 			 * Record the mbuf that points to the mbuf that we're
1843 			 * about to go to work on so that we can update the
1844 			 * m_next appropriately later.
1845 			 */
1846 			for (; n->m_next != m; n = n->m_next)
1847 				;
1848 		} else {
1849 			n = NULL;
1850 		}
1851 
1852 #ifdef MHLEN
1853 		if (len > MHLEN)
1854 #else
1855 		if (len > MLEN)
1856 #endif
1857 		{
1858 #ifdef HAVE_M_PULLDOWN
1859 			if (m_pulldown(m, 0, len, NULL) == NULL)
1860 				m = NULL;
1861 #else
1862 			FREE_MB_T(*fin->fin_mp);
1863 			m = NULL;
1864 			n = NULL;
1865 #endif
1866 		} else
1867 		{
1868 			m = m_pullup(m, len);
1869 		}
1870 		if (n != NULL)
1871 			n->m_next = m;
1872 		if (m == NULL) {
1873 			/*
1874 			 * When n is non-NULL, it indicates that m pointed to
1875 			 * a sub-chain (tail) of the mbuf and that the head
1876 			 * of this chain has not yet been free'd.
1877 			 */
1878 			if (n != NULL) {
1879 				FREE_MB_T(*fin->fin_mp);
1880 			}
1881 
1882 			*fin->fin_mp = NULL;
1883 			fin->fin_m = NULL;
1884 			return NULL;
1885 		}
1886 
1887 		if (n == NULL)
1888 			*fin->fin_mp = m;
1889 
1890 		while (M_LEN(m) == 0) {
1891 			m = m->m_next;
1892 		}
1893 		fin->fin_m = m;
1894 		ip = MTOD(m, char *) + ipoff;
1895 
1896 		fin->fin_ip = (ip_t *)ip;
1897 		if (fin->fin_dp != NULL)
1898 			fin->fin_dp = (char *)fin->fin_ip + dpoff;
1899 		if (fin->fin_fraghdr != NULL)
1900 			fin->fin_fraghdr = (char *)ip +
1901 					   ((char *)fin->fin_fraghdr -
1902 					    (char *)fin->fin_ip);
1903 	}
1904 
1905 	if (len == fin->fin_plen)
1906 		fin->fin_flx |= FI_COALESCE;
1907 	return ip;
1908 }
1909 
1910 
1911 int
1912 ipf_inject(fr_info_t *fin, mb_t *m)
1913 {
1914 	int error;
1915 
1916 	if (fin->fin_out == 0) {
1917 		struct ifqueue *ifq;
1918 
1919 		ifq = &ipintrq;
1920 
1921 		if (IF_QFULL(ifq)) {
1922 			IF_DROP(ifq);
1923 			FREE_MB_T(m);
1924 			error = ENOBUFS;
1925 		} else {
1926 			IF_ENQUEUE(ifq, m);
1927 			error = 0;
1928 		}
1929 	} else {
1930 		error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL);
1931 	}
1932 
1933 	return error;
1934 }
1935 
1936 
1937 u_32_t
1938 ipf_random(void)
1939 {
1940 	int number;
1941 
1942 #ifdef _CPRNG_H
1943 	number = cprng_fast32();
1944 #else
1945 	number = arc4random();
1946 #endif
1947 	return number;
1948 }
1949 
1950 
1951 /*
1952  * routines below for saving IP headers to buffer
1953  */
1954 static int ipfopen(dev_t dev, int flags
1955 #if (NetBSD >= 199511)
1956     , int devtype, PROC_T *p
1957 #endif
1958 )
1959 {
1960 	u_int unit = GET_MINOR(dev);
1961 	int error;
1962 
1963 	if (IPL_LOGMAX < unit) {
1964 		error = ENXIO;
1965 	} else {
1966 		switch (unit)
1967 		{
1968 		case IPL_LOGIPF :
1969 		case IPL_LOGNAT :
1970 		case IPL_LOGSTATE :
1971 		case IPL_LOGAUTH :
1972 		case IPL_LOGLOOKUP :
1973 		case IPL_LOGSYNC :
1974 #ifdef IPFILTER_SCAN
1975 		case IPL_LOGSCAN :
1976 #endif
1977 			error = 0;
1978 			break;
1979 		default :
1980 			error = ENXIO;
1981 			break;
1982 		}
1983 	}
1984 	return error;
1985 }
1986 
1987 
1988 static int ipfclose(dev_t dev, int flags
1989 #if (NetBSD >= 199511)
1990 	, int devtype, PROC_T *p
1991 #endif
1992 )
1993 {
1994 	u_int	unit = GET_MINOR(dev);
1995 
1996 	if (IPL_LOGMAX < unit)
1997 		unit = ENXIO;
1998 	else
1999 		unit = 0;
2000 	return unit;
2001 }
2002 
2003 /*
2004  * ipfread/ipflog
2005  * both of these must operate with at least splnet() lest they be
2006  * called during packet processing and cause an inconsistancy to appear in
2007  * the filter lists.
2008  */
2009 static int ipfread(dev_t dev, struct uio *uio, int ioflag)
2010 {
2011 
2012 	if (ipfmain.ipf_running < 1) {
2013 		ipfmain.ipf_interror = 130006;
2014 		return EIO;
2015 	}
2016 
2017 	if (GET_MINOR(dev) == IPL_LOGSYNC)
2018 		return ipf_sync_read(&ipfmain, uio);
2019 
2020 #ifdef IPFILTER_LOG
2021 	return ipf_log_read(&ipfmain, GET_MINOR(dev), uio);
2022 #else
2023 	ipfmain.ipf_interror = 130007;
2024 	return ENXIO;
2025 #endif
2026 }
2027 
2028 
2029 /*
2030  * ipfwrite
2031  * both of these must operate with at least splnet() lest they be
2032  * called during packet processing and cause an inconsistancy to appear in
2033  * the filter lists.
2034  */
2035 static int ipfwrite(dev_t dev, struct uio *uio, int ioflag)
2036 {
2037 
2038 	if (ipfmain.ipf_running < 1) {
2039 		ipfmain.ipf_interror = 130008;
2040 		return EIO;
2041 	}
2042 
2043 	if (GET_MINOR(dev) == IPL_LOGSYNC)
2044 		return ipf_sync_write(&ipfmain, uio);
2045 	ipfmain.ipf_interror = 130009;
2046 	return ENXIO;
2047 }
2048 
2049 
2050 static int ipfpoll(dev_t dev, int events, PROC_T *p)
2051 {
2052 	u_int unit = GET_MINOR(dev);
2053 	int revents = 0;
2054 
2055 	if (IPL_LOGMAX < unit) {
2056 		ipfmain.ipf_interror = 130010;
2057 		return ENXIO;
2058 	}
2059 
2060 	switch (unit)
2061 	{
2062 	case IPL_LOGIPF :
2063 	case IPL_LOGNAT :
2064 	case IPL_LOGSTATE :
2065 #ifdef IPFILTER_LOG
2066 		if ((events & (POLLIN | POLLRDNORM)) &&
2067 		    ipf_log_canread(&ipfmain, unit))
2068 			revents |= events & (POLLIN | POLLRDNORM);
2069 #endif
2070 		break;
2071 	case IPL_LOGAUTH :
2072 		if ((events & (POLLIN | POLLRDNORM)) &&
2073 		    ipf_auth_waiting(&ipfmain))
2074 			revents |= events & (POLLIN | POLLRDNORM);
2075 		break;
2076 	case IPL_LOGSYNC :
2077 		if ((events & (POLLIN | POLLRDNORM)) &&
2078 		    ipf_sync_canread(&ipfmain))
2079 			revents |= events & (POLLIN | POLLRDNORM);
2080 		if ((events & (POLLOUT | POLLWRNORM)) &&
2081 		    ipf_sync_canwrite(&ipfmain))
2082 			revents |= events & (POLLOUT | POLLWRNORM);
2083 		break;
2084 	case IPL_LOGSCAN :
2085 	case IPL_LOGLOOKUP :
2086 	default :
2087 		break;
2088 	}
2089 
2090 	if ((revents == 0) && (((events & (POLLIN|POLLRDNORM)) != 0)))
2091 		selrecord(p, &ipfmain.ipf_selwait[unit]);
2092 	return revents;
2093 }
2094 
2095 u_int
2096 ipf_pcksum(fr_info_t *fin, int hlen, u_int sum)
2097 {
2098 	struct mbuf *m;
2099 	u_int sum2;
2100 	int off;
2101 
2102 	m = fin->fin_m;
2103 	off = (char *)fin->fin_dp - (char *)fin->fin_ip;
2104 	m->m_data += hlen;
2105 	m->m_len -= hlen;
2106 	sum2 = in_cksum(fin->fin_m, fin->fin_plen - off);
2107 	m->m_len += hlen;
2108 	m->m_data -= hlen;
2109 
2110 	/*
2111 	 * Both sum and sum2 are partial sums, so combine them together.
2112 	 */
2113 	sum += ~sum2 & 0xffff;
2114 	while (sum > 0xffff)
2115 		sum = (sum & 0xffff) + (sum >> 16);
2116 	sum2 = ~sum & 0xffff;
2117 	return sum2;
2118 }
2119