1
2 /*
3 * Copyright (C) 2012 by Darren Reed.
4 *
5 * See the IPFILTER.LICENCE file for details on licencing.
6 */
7
8 #if defined(KERNEL) || defined(_KERNEL)
9 # undef KERNEL
10 # undef _KERNEL
11 # define KERNEL 1
12 # define _KERNEL 1
13 #endif
14 #if defined(__FreeBSD__) && \
15 !defined(KLD_MODULE) && !defined(IPFILTER_LKM)
16 # include "opt_inet6.h"
17 #endif
18 #include <sys/param.h>
19 #include <sys/eventhandler.h>
20 #include <sys/conf.h>
21 #include <sys/errno.h>
22 #include <sys/types.h>
23 #include <sys/file.h>
24 #include <sys/fcntl.h>
25 #include <sys/filio.h>
26 #include <sys/time.h>
27 #include <sys/systm.h>
28 #include <sys/dirent.h>
29 #if defined(__FreeBSD__)
30 # include <sys/jail.h>
31 #endif
32 #include <sys/malloc.h>
33 #include <sys/mbuf.h>
34 #include <sys/sockopt.h>
35 #include <sys/socket.h>
36 #include <sys/selinfo.h>
37 #include <net/if.h>
38 #include <net/if_var.h>
39 #include <net/netisr.h>
40 #include <net/route.h>
41 #include <net/route/nhop.h>
42 #include <netinet/in.h>
43 #include <netinet/in_fib.h>
44 #include <netinet/in_pcb.h>
45 #include <netinet/in_var.h>
46 #include <netinet/in_systm.h>
47 #include <netinet/ip.h>
48 #include <netinet/ip_var.h>
49 #include <netinet/tcp.h>
50 #include <netinet/tcp_var.h>
51 #include <net/vnet.h>
52 #include <netinet/udp.h>
53 #include <netinet/tcpip.h>
54 #include <netinet/ip_icmp.h>
55 #include "netinet/ip_compat.h"
56 #ifdef USE_INET6
57 # include <netinet/icmp6.h>
58 #endif
59 #include "netinet/ip_fil.h"
60 #include "netinet/ip_nat.h"
61 #include "netinet/ip_frag.h"
62 #include "netinet/ip_state.h"
63 #include "netinet/ip_proxy.h"
64 #include "netinet/ip_auth.h"
65 #include "netinet/ip_sync.h"
66 #include "netinet/ip_lookup.h"
67 #include "netinet/ip_dstlist.h"
68 #ifdef IPFILTER_SCAN
69 # include "netinet/ip_scan.h"
70 #endif
71 #include "netinet/ip_pool.h"
72 #include <sys/malloc.h>
73 #include <sys/kernel.h>
74 #ifdef CSUM_DATA_VALID
75 # include <machine/in_cksum.h>
76 #endif
77 extern int ip_optcopy(struct ip *, struct ip *);
78
79 #ifdef IPFILTER_M_IPFILTER
80 MALLOC_DEFINE(M_IPFILTER, "ipfilter", "IP Filter packet filter data structures");
81 #endif
82
83
84 static int ipf_send_ip(fr_info_t *, mb_t *);
85 static void ipf_timer_func(void *arg);
86
87 VNET_DEFINE(ipf_main_softc_t, ipfmain) = {
88 .ipf_running = -2,
89 };
90 #define V_ipfmain VNET(ipfmain)
91 #define V0_ipfmain VNET_VNET(vnet0,ipfmain)
92
93 #include <sys/conf.h>
94 #include <net/pfil.h>
95
96 VNET_DEFINE_STATIC(eventhandler_tag, ipf_arrivetag);
97 VNET_DEFINE_STATIC(eventhandler_tag, ipf_departtag);
98 #define V_ipf_arrivetag VNET(ipf_arrivetag)
99 #define V_ipf_departtag VNET(ipf_departtag)
100
101 static void ipf_ifevent(void *arg, struct ifnet *ifp);
102
ipf_ifevent(void * arg,struct ifnet * ifp)103 static void ipf_ifevent(void *arg, struct ifnet *ifp)
104 {
105
106 CURVNET_SET(ifp->if_vnet);
107 if (V_ipfmain.ipf_running > 0)
108 ipf_sync(&V_ipfmain, NULL);
109 CURVNET_RESTORE();
110 }
111
112
113
114 static pfil_return_t
ipf_check_wrapper(struct mbuf ** mp,struct ifnet * ifp,int flags,void * ruleset __unused,struct inpcb * inp)115 ipf_check_wrapper(struct mbuf **mp, struct ifnet *ifp, int flags,
116 void *ruleset __unused, struct inpcb *inp)
117 {
118 struct ip *ip = mtod(*mp, struct ip *);
119 pfil_return_t rv;
120
121 CURVNET_SET(ifp->if_vnet);
122 rv = ipf_check(&V_ipfmain, ip, ip->ip_hl << 2, ifp,
123 !!(flags & PFIL_OUT), mp);
124 CURVNET_RESTORE();
125 if (rv == 0 && *mp == NULL)
126 return (PFIL_CONSUMED);
127 return (rv == 0 ? PFIL_PASS : PFIL_DROPPED);
128 }
129
130 #ifdef USE_INET6
131 static pfil_return_t
ipf_check_wrapper6(struct mbuf ** mp,struct ifnet * ifp,int flags,void * ruleset __unused,struct inpcb * inp)132 ipf_check_wrapper6(struct mbuf **mp, struct ifnet *ifp, int flags,
133 void *ruleset __unused, struct inpcb *inp)
134 {
135 pfil_return_t rv;
136
137 CURVNET_SET(ifp->if_vnet);
138 rv = ipf_check(&V_ipfmain, mtod(*mp, struct ip *),
139 sizeof(struct ip6_hdr), ifp, !!(flags & PFIL_OUT), mp);
140 CURVNET_RESTORE();
141 if (rv == 0 && *mp == NULL)
142 return (PFIL_CONSUMED);
143
144 return (rv == 0 ? PFIL_PASS : PFIL_DROPPED);
145 }
146 # endif
147 #if defined(IPFILTER_LKM)
ipf_identify(char * s)148 int ipf_identify(char *s)
149 {
150 if (strcmp(s, "ipl") == 0)
151 return (1);
152 return (0);
153 }
154 #endif /* IPFILTER_LKM */
155
156
157 static void
ipf_timer_func(void * arg)158 ipf_timer_func(void *arg)
159 {
160 ipf_main_softc_t *softc = arg;
161 SPL_INT(s);
162
163 SPL_NET(s);
164
165 if (softc->ipf_running > 0)
166 ipf_slowtimer(softc);
167
168 if (softc->ipf_running == -1 || softc->ipf_running == 1) {
169 callout_reset(&softc->ipf_slow_ch,
170 (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT,
171 ipf_timer_func, softc);
172 }
173 SPL_X(s);
174 }
175
176
177 int
ipfattach(ipf_main_softc_t * softc)178 ipfattach(ipf_main_softc_t *softc)
179 {
180 #ifdef USE_SPL
181 int s;
182 #endif
183
184 SPL_NET(s);
185 if (softc->ipf_running > 0) {
186 SPL_X(s);
187 return (EBUSY);
188 }
189
190 if (ipf_init_all(softc) < 0) {
191 SPL_X(s);
192 return (EIO);
193 }
194
195
196 bzero((char *)V_ipfmain.ipf_selwait, sizeof(V_ipfmain.ipf_selwait));
197 softc->ipf_running = 1;
198
199 if (softc->ipf_control_forwarding & 1)
200 V_ipforwarding = 1;
201
202 SPL_X(s);
203 callout_init_rw(&softc->ipf_slow_ch, &softc->ipf_global.ipf_lk, CALLOUT_SHAREDLOCK);
204 callout_reset(&softc->ipf_slow_ch, (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT,
205 ipf_timer_func, softc);
206 return (0);
207 }
208
209
210 /*
211 * Disable the filter by removing the hooks from the IP input/output
212 * stream.
213 */
214 int
ipfdetach(ipf_main_softc_t * softc)215 ipfdetach(ipf_main_softc_t *softc)
216 {
217 #ifdef USE_SPL
218 int s;
219 #endif
220
221 if (softc->ipf_control_forwarding & 2)
222 V_ipforwarding = 0;
223
224 SPL_NET(s);
225
226 callout_drain(&softc->ipf_slow_ch);
227
228 ipf_fini_all(softc);
229
230 softc->ipf_running = -2;
231
232 SPL_X(s);
233
234 return (0);
235 }
236
237
238 /*
239 * Filter ioctl interface.
240 */
241 int
ipfioctl(struct cdev * dev,ioctlcmd_t cmd,caddr_t data,int mode,struct thread * p)242 ipfioctl(struct cdev *dev, ioctlcmd_t cmd, caddr_t data,
243 int mode, struct thread *p)
244 #define p_cred td_ucred
245 #define p_uid td_ucred->cr_ruid
246 {
247 int error = 0, unit = 0;
248 SPL_INT(s);
249
250 CURVNET_SET(TD_TO_VNET(p));
251 if (securelevel_ge(p->p_cred, 3) && (mode & FWRITE))
252 {
253 V_ipfmain.ipf_interror = 130001;
254 CURVNET_RESTORE();
255 return (EPERM);
256 }
257
258 /*
259 * Remember, the host system (with its vnet0) controls
260 * whether a jail is allowed to use ipfilter or not.
261 * The default is ipfilter cannot be used by a jail
262 * unless the sysctl allows it.
263 */
264 if (V0_ipfmain.ipf_jail_allowed == 0) {
265 if (jailed(p->p_cred)) {
266 V_ipfmain.ipf_interror = 130019;
267 CURVNET_RESTORE();
268 return (EOPNOTSUPP);
269 }
270 }
271
272 if (jailed_without_vnet(p->p_cred)) {
273 V_ipfmain.ipf_interror = 130018;
274 CURVNET_RESTORE();
275 return (EOPNOTSUPP);
276 }
277
278 unit = GET_MINOR(dev);
279 if ((IPL_LOGMAX < unit) || (unit < 0)) {
280 V_ipfmain.ipf_interror = 130002;
281 CURVNET_RESTORE();
282 return (ENXIO);
283 }
284
285 if (V_ipfmain.ipf_running <= 0) {
286 if (unit != IPL_LOGIPF && cmd != SIOCIPFINTERROR) {
287 V_ipfmain.ipf_interror = 130003;
288 CURVNET_RESTORE();
289 return (EIO);
290 }
291 if (cmd != SIOCIPFGETNEXT && cmd != SIOCIPFGET &&
292 cmd != SIOCIPFSET && cmd != SIOCFRENB &&
293 cmd != SIOCGETFS && cmd != SIOCGETFF &&
294 cmd != SIOCIPFINTERROR) {
295 V_ipfmain.ipf_interror = 130004;
296 CURVNET_RESTORE();
297 return (EIO);
298 }
299 }
300
301 SPL_NET(s);
302
303 error = ipf_ioctlswitch(&V_ipfmain, unit, data, cmd, mode, p->p_uid, p);
304 CURVNET_RESTORE();
305 if (error != -1) {
306 SPL_X(s);
307 return (error);
308 }
309
310 SPL_X(s);
311
312 return (error);
313 }
314
315
316 /*
317 * ipf_send_reset - this could conceivably be a call to tcp_respond(), but that
318 * requires a large amount of setting up and isn't any more efficient.
319 */
320 int
ipf_send_reset(fr_info_t * fin)321 ipf_send_reset(fr_info_t *fin)
322 {
323 struct tcphdr *tcp, *tcp2;
324 int tlen = 0, hlen;
325 struct mbuf *m;
326 #ifdef USE_INET6
327 ip6_t *ip6;
328 #endif
329 ip_t *ip;
330
331 tcp = fin->fin_dp;
332 if (tcp_get_flags(tcp) & TH_RST)
333 return (-1); /* feedback loop */
334
335 if (ipf_checkl4sum(fin) == -1)
336 return (-1);
337
338 tlen = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
339 ((tcp_get_flags(tcp) & TH_SYN) ? 1 : 0) +
340 ((tcp_get_flags(tcp) & TH_FIN) ? 1 : 0);
341
342 #ifdef USE_INET6
343 hlen = (fin->fin_v == 6) ? sizeof(ip6_t) : sizeof(ip_t);
344 #else
345 hlen = sizeof(ip_t);
346 #endif
347 #ifdef MGETHDR
348 MGETHDR(m, M_NOWAIT, MT_HEADER);
349 #else
350 MGET(m, M_NOWAIT, MT_HEADER);
351 #endif
352 if (m == NULL)
353 return (-1);
354 if (sizeof(*tcp2) + hlen > MLEN) {
355 if (!(MCLGET(m, M_NOWAIT))) {
356 FREE_MB_T(m);
357 return (-1);
358 }
359 }
360
361 m->m_len = sizeof(*tcp2) + hlen;
362 m->m_data += max_linkhdr;
363 m->m_pkthdr.len = m->m_len;
364 m->m_pkthdr.rcvif = (struct ifnet *)0;
365 ip = mtod(m, struct ip *);
366 bzero((char *)ip, hlen);
367 #ifdef USE_INET6
368 ip6 = (ip6_t *)ip;
369 #endif
370 tcp2 = (struct tcphdr *)((char *)ip + hlen);
371 tcp2->th_sport = tcp->th_dport;
372 tcp2->th_dport = tcp->th_sport;
373
374 if (tcp_get_flags(tcp) & TH_ACK) {
375 tcp2->th_seq = tcp->th_ack;
376 tcp_set_flags(tcp2, TH_RST);
377 tcp2->th_ack = 0;
378 } else {
379 tcp2->th_seq = 0;
380 tcp2->th_ack = ntohl(tcp->th_seq);
381 tcp2->th_ack += tlen;
382 tcp2->th_ack = htonl(tcp2->th_ack);
383 tcp_set_flags(tcp2, TH_RST|TH_ACK);
384 }
385 TCP_OFF_A(tcp2, sizeof(*tcp2) >> 2);
386 tcp2->th_win = tcp->th_win;
387 tcp2->th_sum = 0;
388 tcp2->th_urp = 0;
389
390 #ifdef USE_INET6
391 if (fin->fin_v == 6) {
392 ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
393 ip6->ip6_plen = htons(sizeof(struct tcphdr));
394 ip6->ip6_nxt = IPPROTO_TCP;
395 ip6->ip6_hlim = 0;
396 ip6->ip6_src = fin->fin_dst6.in6;
397 ip6->ip6_dst = fin->fin_src6.in6;
398 tcp2->th_sum = in6_cksum(m, IPPROTO_TCP,
399 sizeof(*ip6), sizeof(*tcp2));
400 return (ipf_send_ip(fin, m));
401 }
402 #endif
403 ip->ip_p = IPPROTO_TCP;
404 ip->ip_len = htons(sizeof(struct tcphdr));
405 ip->ip_src.s_addr = fin->fin_daddr;
406 ip->ip_dst.s_addr = fin->fin_saddr;
407 tcp2->th_sum = in_cksum(m, hlen + sizeof(*tcp2));
408 ip->ip_len = htons(hlen + sizeof(*tcp2));
409 return (ipf_send_ip(fin, m));
410 }
411
412
413 /*
414 * ip_len must be in network byte order when called.
415 */
416 static int
ipf_send_ip(fr_info_t * fin,mb_t * m)417 ipf_send_ip(fr_info_t *fin, mb_t *m)
418 {
419 fr_info_t fnew;
420 ip_t *ip, *oip;
421 int hlen;
422
423 ip = mtod(m, ip_t *);
424 bzero((char *)&fnew, sizeof(fnew));
425 fnew.fin_main_soft = fin->fin_main_soft;
426
427 IP_V_A(ip, fin->fin_v);
428 switch (fin->fin_v)
429 {
430 case 4 :
431 oip = fin->fin_ip;
432 hlen = sizeof(*oip);
433 fnew.fin_v = 4;
434 fnew.fin_p = ip->ip_p;
435 fnew.fin_plen = ntohs(ip->ip_len);
436 IP_HL_A(ip, sizeof(*oip) >> 2);
437 ip->ip_tos = oip->ip_tos;
438 ip->ip_id = fin->fin_ip->ip_id;
439 ip->ip_off = htons(V_path_mtu_discovery ? IP_DF : 0);
440 ip->ip_ttl = V_ip_defttl;
441 ip->ip_sum = 0;
442 break;
443 #ifdef USE_INET6
444 case 6 :
445 {
446 ip6_t *ip6 = (ip6_t *)ip;
447
448 ip6->ip6_vfc = 0x60;
449 ip6->ip6_hlim = IPDEFTTL;
450
451 hlen = sizeof(*ip6);
452 fnew.fin_p = ip6->ip6_nxt;
453 fnew.fin_v = 6;
454 fnew.fin_plen = ntohs(ip6->ip6_plen) + hlen;
455 break;
456 }
457 #endif
458 default :
459 return (EINVAL);
460 }
461 #ifdef IPSEC_SUPPORT
462 m->m_pkthdr.rcvif = NULL;
463 #endif
464
465 fnew.fin_ifp = fin->fin_ifp;
466 fnew.fin_flx = FI_NOCKSUM;
467 fnew.fin_m = m;
468 fnew.fin_ip = ip;
469 fnew.fin_mp = &m;
470 fnew.fin_hlen = hlen;
471 fnew.fin_dp = (char *)ip + hlen;
472 (void) ipf_makefrip(hlen, ip, &fnew);
473
474 return (ipf_fastroute(m, &m, &fnew, NULL));
475 }
476
477
478 int
ipf_send_icmp_err(int type,fr_info_t * fin,int dst)479 ipf_send_icmp_err(int type, fr_info_t *fin, int dst)
480 {
481 int err, hlen, xtra, iclen, ohlen, avail;
482 struct in_addr dst4;
483 struct icmp *icmp;
484 struct mbuf *m;
485 i6addr_t dst6;
486 void *ifp;
487 #ifdef USE_INET6
488 int code;
489 ip6_t *ip6;
490 #endif
491 ip_t *ip, *ip2;
492
493 if ((type < 0) || (type >= ICMP_MAXTYPE))
494 return (-1);
495
496 #ifdef USE_INET6
497 code = fin->fin_icode;
498 /* See NetBSD ip_fil_netbsd.c r1.4: */
499 if ((code < 0) || (code >= sizeof(icmptoicmp6unreach)/sizeof(int)))
500 return (-1);
501 #endif
502
503 if (ipf_checkl4sum(fin) == -1)
504 return (-1);
505 #ifdef MGETHDR
506 MGETHDR(m, M_NOWAIT, MT_HEADER);
507 #else
508 MGET(m, M_NOWAIT, MT_HEADER);
509 #endif
510 if (m == NULL)
511 return (-1);
512 avail = MHLEN;
513
514 xtra = 0;
515 hlen = 0;
516 ohlen = 0;
517 dst4.s_addr = 0;
518 ifp = fin->fin_ifp;
519 if (fin->fin_v == 4) {
520 if ((fin->fin_p == IPPROTO_ICMP) && !(fin->fin_flx & FI_SHORT))
521 switch (ntohs(fin->fin_data[0]) >> 8)
522 {
523 case ICMP_ECHO :
524 case ICMP_TSTAMP :
525 case ICMP_IREQ :
526 case ICMP_MASKREQ :
527 break;
528 default :
529 FREE_MB_T(m);
530 return (0);
531 }
532
533 if (dst == 0) {
534 if (ipf_ifpaddr(&V_ipfmain, 4, FRI_NORMAL, ifp,
535 &dst6, NULL) == -1) {
536 FREE_MB_T(m);
537 return (-1);
538 }
539 dst4 = dst6.in4;
540 } else
541 dst4.s_addr = fin->fin_daddr;
542
543 hlen = sizeof(ip_t);
544 ohlen = fin->fin_hlen;
545 iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
546 if (fin->fin_hlen < fin->fin_plen)
547 xtra = MIN(fin->fin_dlen, 8);
548 else
549 xtra = 0;
550 }
551
552 #ifdef USE_INET6
553 else if (fin->fin_v == 6) {
554 hlen = sizeof(ip6_t);
555 ohlen = sizeof(ip6_t);
556 iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
557 type = icmptoicmp6types[type];
558 if (type == ICMP6_DST_UNREACH)
559 code = icmptoicmp6unreach[code];
560
561 if (iclen + max_linkhdr + fin->fin_plen > avail) {
562 if (!(MCLGET(m, M_NOWAIT))) {
563 FREE_MB_T(m);
564 return (-1);
565 }
566 avail = MCLBYTES;
567 }
568 xtra = MIN(fin->fin_plen, avail - iclen - max_linkhdr);
569 xtra = MIN(xtra, IPV6_MMTU - iclen);
570 if (dst == 0) {
571 if (ipf_ifpaddr(&V_ipfmain, 6, FRI_NORMAL, ifp,
572 &dst6, NULL) == -1) {
573 FREE_MB_T(m);
574 return (-1);
575 }
576 } else
577 dst6 = fin->fin_dst6;
578 }
579 #endif
580 else {
581 FREE_MB_T(m);
582 return (-1);
583 }
584
585 avail -= (max_linkhdr + iclen);
586 if (avail < 0) {
587 FREE_MB_T(m);
588 return (-1);
589 }
590 if (xtra > avail)
591 xtra = avail;
592 iclen += xtra;
593 m->m_data += max_linkhdr;
594 m->m_pkthdr.rcvif = (struct ifnet *)0;
595 m->m_pkthdr.len = iclen;
596 m->m_len = iclen;
597 ip = mtod(m, ip_t *);
598 icmp = (struct icmp *)((char *)ip + hlen);
599 ip2 = (ip_t *)&icmp->icmp_ip;
600
601 icmp->icmp_type = type;
602 icmp->icmp_code = fin->fin_icode;
603 icmp->icmp_cksum = 0;
604 #ifdef icmp_nextmtu
605 if (type == ICMP_UNREACH && fin->fin_icode == ICMP_UNREACH_NEEDFRAG) {
606 if (fin->fin_mtu != 0) {
607 icmp->icmp_nextmtu = htons(fin->fin_mtu);
608
609 } else if (ifp != NULL) {
610 icmp->icmp_nextmtu = htons(GETIFMTU_4(ifp));
611
612 } else { /* make up a number... */
613 icmp->icmp_nextmtu = htons(fin->fin_plen - 20);
614 }
615 }
616 #endif
617
618 bcopy((char *)fin->fin_ip, (char *)ip2, ohlen);
619
620 #ifdef USE_INET6
621 ip6 = (ip6_t *)ip;
622 if (fin->fin_v == 6) {
623 ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
624 ip6->ip6_plen = htons(iclen - hlen);
625 ip6->ip6_nxt = IPPROTO_ICMPV6;
626 ip6->ip6_hlim = 0;
627 ip6->ip6_src = dst6.in6;
628 ip6->ip6_dst = fin->fin_src6.in6;
629 if (xtra > 0)
630 bcopy((char *)fin->fin_ip + ohlen,
631 (char *)&icmp->icmp_ip + ohlen, xtra);
632 icmp->icmp_cksum = in6_cksum(m, IPPROTO_ICMPV6,
633 sizeof(*ip6), iclen - hlen);
634 } else
635 #endif
636 {
637 ip->ip_p = IPPROTO_ICMP;
638 ip->ip_src.s_addr = dst4.s_addr;
639 ip->ip_dst.s_addr = fin->fin_saddr;
640
641 if (xtra > 0)
642 bcopy((char *)fin->fin_ip + ohlen,
643 (char *)&icmp->icmp_ip + ohlen, xtra);
644 icmp->icmp_cksum = ipf_cksum((u_short *)icmp,
645 sizeof(*icmp) + 8);
646 ip->ip_len = htons(iclen);
647 ip->ip_p = IPPROTO_ICMP;
648 }
649 err = ipf_send_ip(fin, m);
650 return (err);
651 }
652
653
654
655
656 /*
657 * m0 - pointer to mbuf where the IP packet starts
658 * mpp - pointer to the mbuf pointer that is the start of the mbuf chain
659 */
660 int
ipf_fastroute(mb_t * m0,mb_t ** mpp,fr_info_t * fin,frdest_t * fdp)661 ipf_fastroute(mb_t *m0, mb_t **mpp, fr_info_t *fin, frdest_t *fdp)
662 {
663 register struct ip *ip, *mhip;
664 register struct mbuf *m = *mpp;
665 int len, off, error = 0, hlen, code;
666 struct ifnet *ifp, *sifp;
667 struct route ro;
668 struct sockaddr_in *dst;
669 const struct sockaddr *gw;
670 struct nhop_object *nh;
671 u_long fibnum = 0;
672 u_short ip_off;
673 frdest_t node;
674 frentry_t *fr;
675
676 #ifdef M_WRITABLE
677 /*
678 * HOT FIX/KLUDGE:
679 *
680 * If the mbuf we're about to send is not writable (because of
681 * a cluster reference, for example) we'll need to make a copy
682 * of it since this routine modifies the contents.
683 *
684 * If you have non-crappy network hardware that can transmit data
685 * from the mbuf, rather than making a copy, this is gonna be a
686 * problem.
687 */
688 if (M_WRITABLE(m) == 0) {
689 m0 = m_dup(m, M_NOWAIT);
690 if (m0 != NULL) {
691 FREE_MB_T(m);
692 m = m0;
693 *mpp = m;
694 } else {
695 error = ENOBUFS;
696 FREE_MB_T(m);
697 goto done;
698 }
699 }
700 #endif
701
702 #ifdef USE_INET6
703 if (fin->fin_v == 6) {
704 /*
705 * currently "to <if>" and "to <if>:ip#" are not supported
706 * for IPv6
707 */
708 return (ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL));
709 }
710 #endif
711
712 hlen = fin->fin_hlen;
713 ip = mtod(m0, struct ip *);
714 ifp = NULL;
715
716 /*
717 * Route packet.
718 */
719 bzero(&ro, sizeof (ro));
720 dst = (struct sockaddr_in *)&ro.ro_dst;
721 dst->sin_family = AF_INET;
722 dst->sin_addr = ip->ip_dst;
723 dst->sin_len = sizeof(dst);
724 gw = (const struct sockaddr *)dst;
725
726 fr = fin->fin_fr;
727 if ((fr != NULL) && !(fr->fr_flags & FR_KEEPSTATE) && (fdp != NULL) &&
728 (fdp->fd_type == FRD_DSTLIST)) {
729 if (ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, &node) == 0)
730 fdp = &node;
731 }
732
733 if (fdp != NULL)
734 ifp = fdp->fd_ptr;
735 else
736 ifp = fin->fin_ifp;
737
738 if ((ifp == NULL) && ((fr == NULL) || !(fr->fr_flags & FR_FASTROUTE))) {
739 error = -2;
740 goto bad;
741 }
742
743 if ((fdp != NULL) && (fdp->fd_ip.s_addr != 0))
744 dst->sin_addr = fdp->fd_ip;
745
746 fibnum = M_GETFIB(m0);
747 NET_EPOCH_ASSERT();
748 nh = fib4_lookup(fibnum, dst->sin_addr, 0, NHR_NONE, 0);
749 if (nh == NULL) {
750 if (in_localaddr(ip->ip_dst))
751 error = EHOSTUNREACH;
752 else
753 error = ENETUNREACH;
754 goto bad;
755 }
756
757 if (ifp == NULL)
758 ifp = nh->nh_ifp;
759 if (nh->nh_flags & NHF_GATEWAY) {
760 gw = &nh->gw_sa;
761 ro.ro_flags |= RT_HAS_GW;
762 }
763
764 /*
765 * For input packets which are being "fastrouted", they won't
766 * go back through output filtering and miss their chance to get
767 * NAT'd and counted. Duplicated packets aren't considered to be
768 * part of the normal packet stream, so do not NAT them or pass
769 * them through stateful checking, etc.
770 */
771 if ((fdp != &fr->fr_dif) && (fin->fin_out == 0)) {
772 sifp = fin->fin_ifp;
773 fin->fin_ifp = ifp;
774 fin->fin_out = 1;
775 (void) ipf_acctpkt(fin, NULL);
776 fin->fin_fr = NULL;
777 if (!fr || !(fr->fr_flags & FR_RETMASK)) {
778 u_32_t pass;
779
780 (void) ipf_state_check(fin, &pass);
781 }
782
783 switch (ipf_nat_checkout(fin, NULL))
784 {
785 case 0 :
786 break;
787 case 1 :
788 ip->ip_sum = 0;
789 break;
790 case -1 :
791 error = -1;
792 goto bad;
793 break;
794 }
795
796 fin->fin_ifp = sifp;
797 fin->fin_out = 0;
798 } else
799 ip->ip_sum = 0;
800 /*
801 * If small enough for interface, can just send directly.
802 */
803 if (ntohs(ip->ip_len) <= ifp->if_mtu) {
804 if (!ip->ip_sum)
805 ip->ip_sum = in_cksum(m, hlen);
806 error = (*ifp->if_output)(ifp, m, gw, &ro);
807 goto done;
808 }
809 /*
810 * Too large for interface; fragment if possible.
811 * Must be able to put at least 8 bytes per fragment.
812 */
813 ip_off = ntohs(ip->ip_off);
814 if (ip_off & IP_DF) {
815 error = EMSGSIZE;
816 goto bad;
817 }
818 len = (ifp->if_mtu - hlen) &~ 7;
819 if (len < 8) {
820 error = EMSGSIZE;
821 goto bad;
822 }
823
824 {
825 int mhlen, firstlen = len;
826 struct mbuf **mnext = &m->m_act;
827
828 /*
829 * Loop through length of segment after first fragment,
830 * make new header and copy data of each part and link onto chain.
831 */
832 m0 = m;
833 mhlen = sizeof (struct ip);
834 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) {
835 #ifdef MGETHDR
836 MGETHDR(m, M_NOWAIT, MT_HEADER);
837 #else
838 MGET(m, M_NOWAIT, MT_HEADER);
839 #endif
840 if (m == NULL) {
841 m = m0;
842 error = ENOBUFS;
843 goto bad;
844 }
845 m->m_data += max_linkhdr;
846 mhip = mtod(m, struct ip *);
847 bcopy((char *)ip, (char *)mhip, sizeof(*ip));
848 if (hlen > sizeof (struct ip)) {
849 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
850 IP_HL_A(mhip, mhlen >> 2);
851 }
852 m->m_len = mhlen;
853 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
854 if (off + len >= ntohs(ip->ip_len))
855 len = ntohs(ip->ip_len) - off;
856 else
857 mhip->ip_off |= IP_MF;
858 mhip->ip_len = htons((u_short)(len + mhlen));
859 *mnext = m;
860 m->m_next = m_copym(m0, off, len, M_NOWAIT);
861 if (m->m_next == 0) {
862 error = ENOBUFS; /* ??? */
863 goto sendorfree;
864 }
865 m->m_pkthdr.len = mhlen + len;
866 m->m_pkthdr.rcvif = NULL;
867 mhip->ip_off = htons((u_short)mhip->ip_off);
868 mhip->ip_sum = 0;
869 mhip->ip_sum = in_cksum(m, mhlen);
870 mnext = &m->m_act;
871 }
872 /*
873 * Update first fragment by trimming what's been copied out
874 * and updating header, then send each fragment (in order).
875 */
876 m_adj(m0, hlen + firstlen - ip->ip_len);
877 ip->ip_len = htons((u_short)(hlen + firstlen));
878 ip->ip_off = htons((u_short)IP_MF);
879 ip->ip_sum = 0;
880 ip->ip_sum = in_cksum(m0, hlen);
881 sendorfree:
882 for (m = m0; m; m = m0) {
883 m0 = m->m_act;
884 m->m_act = 0;
885 if (error == 0)
886 error = (*ifp->if_output)(ifp, m, gw, &ro);
887 else
888 FREE_MB_T(m);
889 }
890 }
891 done:
892 if (!error)
893 V_ipfmain.ipf_frouteok[0]++;
894 else
895 V_ipfmain.ipf_frouteok[1]++;
896
897 return (0);
898 bad:
899 if (error == EMSGSIZE) {
900 sifp = fin->fin_ifp;
901 code = fin->fin_icode;
902 fin->fin_icode = ICMP_UNREACH_NEEDFRAG;
903 fin->fin_ifp = ifp;
904 (void) ipf_send_icmp_err(ICMP_UNREACH, fin, 1);
905 fin->fin_ifp = sifp;
906 fin->fin_icode = code;
907 }
908 FREE_MB_T(m);
909 goto done;
910 }
911
912
913 int
ipf_verifysrc(fr_info_t * fin)914 ipf_verifysrc(fr_info_t *fin)
915 {
916 struct nhop_object *nh;
917
918 NET_EPOCH_ASSERT();
919 nh = fib4_lookup(RT_DEFAULT_FIB, fin->fin_src, 0, NHR_NONE, 0);
920 if (nh == NULL)
921 return (0);
922 return (fin->fin_ifp == nh->nh_ifp);
923 }
924
925
926 /*
927 * return the first IP Address associated with an interface
928 */
929 int
ipf_ifpaddr(ipf_main_softc_t * softc,int v,int atype,void * ifptr,i6addr_t * inp,i6addr_t * inpmask)930 ipf_ifpaddr(ipf_main_softc_t *softc, int v, int atype, void *ifptr,
931 i6addr_t *inp, i6addr_t *inpmask)
932 {
933 #ifdef USE_INET6
934 struct in6_addr *ia6 = NULL;
935 #endif
936 struct sockaddr *sock, *mask;
937 struct sockaddr_in *sin;
938 struct ifaddr *ifa;
939 struct ifnet *ifp;
940
941 if ((ifptr == NULL) || (ifptr == (void *)-1))
942 return (-1);
943
944 sin = NULL;
945 ifp = ifptr;
946
947 if (v == 4)
948 inp->in4.s_addr = 0;
949 #ifdef USE_INET6
950 else if (v == 6)
951 bzero((char *)inp, sizeof(*inp));
952 #endif
953 ifa = CK_STAILQ_FIRST(&ifp->if_addrhead);
954
955 sock = ifa->ifa_addr;
956 while (sock != NULL && ifa != NULL) {
957 sin = (struct sockaddr_in *)sock;
958 if ((v == 4) && (sin->sin_family == AF_INET))
959 break;
960 #ifdef USE_INET6
961 if ((v == 6) && (sin->sin_family == AF_INET6)) {
962 ia6 = &((struct sockaddr_in6 *)sin)->sin6_addr;
963 if (!IN6_IS_ADDR_LINKLOCAL(ia6) &&
964 !IN6_IS_ADDR_LOOPBACK(ia6))
965 break;
966 }
967 #endif
968 ifa = CK_STAILQ_NEXT(ifa, ifa_link);
969 if (ifa != NULL)
970 sock = ifa->ifa_addr;
971 }
972
973 if (ifa == NULL || sin == NULL)
974 return (-1);
975
976 mask = ifa->ifa_netmask;
977 if (atype == FRI_BROADCAST)
978 sock = ifa->ifa_broadaddr;
979 else if (atype == FRI_PEERADDR)
980 sock = ifa->ifa_dstaddr;
981
982 if (sock == NULL)
983 return (-1);
984
985 #ifdef USE_INET6
986 if (v == 6) {
987 return (ipf_ifpfillv6addr(atype, (struct sockaddr_in6 *)sock,
988 (struct sockaddr_in6 *)mask,
989 inp, inpmask));
990 }
991 #endif
992 return (ipf_ifpfillv4addr(atype, (struct sockaddr_in *)sock,
993 (struct sockaddr_in *)mask,
994 &inp->in4, &inpmask->in4));
995 }
996
997
998 u_32_t
ipf_newisn(fr_info_t * fin)999 ipf_newisn(fr_info_t *fin)
1000 {
1001 u_32_t newiss;
1002 newiss = arc4random();
1003 return (newiss);
1004 }
1005
1006
1007 int
ipf_checkv4sum(fr_info_t * fin)1008 ipf_checkv4sum(fr_info_t *fin)
1009 {
1010 #ifdef CSUM_DATA_VALID
1011 int manual = 0;
1012 u_short sum;
1013 ip_t *ip;
1014 mb_t *m;
1015
1016 if ((fin->fin_flx & FI_NOCKSUM) != 0)
1017 return (0);
1018
1019 if ((fin->fin_flx & FI_SHORT) != 0)
1020 return (1);
1021
1022 if (fin->fin_cksum != FI_CK_NEEDED)
1023 return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1024
1025 m = fin->fin_m;
1026 if (m == NULL) {
1027 manual = 1;
1028 goto skipauto;
1029 }
1030 ip = fin->fin_ip;
1031
1032 if ((m->m_pkthdr.csum_flags & (CSUM_IP_CHECKED|CSUM_IP_VALID)) ==
1033 CSUM_IP_CHECKED) {
1034 fin->fin_cksum = FI_CK_BAD;
1035 fin->fin_flx |= FI_BAD;
1036 DT2(ipf_fi_bad_checkv4sum_csum_ip_checked, fr_info_t *, fin, u_int, m->m_pkthdr.csum_flags & (CSUM_IP_CHECKED|CSUM_IP_VALID));
1037 return (-1);
1038 }
1039 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
1040 /* Depending on the driver, UDP may have zero checksum */
1041 if (fin->fin_p == IPPROTO_UDP && (fin->fin_flx &
1042 (FI_FRAG|FI_SHORT|FI_BAD)) == 0) {
1043 udphdr_t *udp = fin->fin_dp;
1044 if (udp->uh_sum == 0) {
1045 /*
1046 * we're good no matter what the hardware
1047 * checksum flags and csum_data say (handling
1048 * of csum_data for zero UDP checksum is not
1049 * consistent across all drivers)
1050 */
1051 fin->fin_cksum = 1;
1052 return (0);
1053 }
1054 }
1055
1056 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
1057 sum = m->m_pkthdr.csum_data;
1058 else
1059 sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
1060 htonl(m->m_pkthdr.csum_data +
1061 fin->fin_dlen + fin->fin_p));
1062 sum ^= 0xffff;
1063 if (sum != 0) {
1064 fin->fin_cksum = FI_CK_BAD;
1065 fin->fin_flx |= FI_BAD;
1066 DT2(ipf_fi_bad_checkv4sum_sum, fr_info_t *, fin, u_int, sum);
1067 } else {
1068 fin->fin_cksum = FI_CK_SUMOK;
1069 return (0);
1070 }
1071 } else {
1072 if (m->m_pkthdr.csum_flags == CSUM_DELAY_DATA) {
1073 fin->fin_cksum = FI_CK_L4FULL;
1074 return (0);
1075 } else if (m->m_pkthdr.csum_flags == CSUM_TCP ||
1076 m->m_pkthdr.csum_flags == CSUM_UDP ||
1077 m->m_pkthdr.csum_flags == CSUM_IP) {
1078 fin->fin_cksum = FI_CK_L4PART;
1079 return (0);
1080 } else {
1081 manual = 1;
1082 }
1083 }
1084 skipauto:
1085 if (manual != 0) {
1086 if (ipf_checkl4sum(fin) == -1) {
1087 fin->fin_flx |= FI_BAD;
1088 DT2(ipf_fi_bad_checkv4sum_manual, fr_info_t *, fin, u_int, manual);
1089 return (-1);
1090 }
1091 }
1092 #else
1093 if (ipf_checkl4sum(fin) == -1) {
1094 fin->fin_flx |= FI_BAD;
1095 DT2(ipf_fi_bad_checkv4sum_checkl4sum, fr_info_t *, fin, u_int, -1);
1096 return (-1);
1097 }
1098 #endif
1099 return (0);
1100 }
1101
1102
1103 #ifdef USE_INET6
1104 int
ipf_checkv6sum(fr_info_t * fin)1105 ipf_checkv6sum(fr_info_t *fin)
1106 {
1107 if ((fin->fin_flx & FI_NOCKSUM) != 0) {
1108 DT(ipf_checkv6sum_fi_nocksum);
1109 return (0);
1110 }
1111
1112 if ((fin->fin_flx & FI_SHORT) != 0) {
1113 DT(ipf_checkv6sum_fi_short);
1114 return (1);
1115 }
1116
1117 if (fin->fin_cksum != FI_CK_NEEDED) {
1118 DT(ipf_checkv6sum_fi_ck_needed);
1119 return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1120 }
1121
1122 if (ipf_checkl4sum(fin) == -1) {
1123 fin->fin_flx |= FI_BAD;
1124 DT2(ipf_fi_bad_checkv6sum_checkl4sum, fr_info_t *, fin, u_int, -1);
1125 return (-1);
1126 }
1127 return (0);
1128 }
1129 #endif /* USE_INET6 */
1130
1131
1132 size_t
mbufchainlen(struct mbuf * m0)1133 mbufchainlen(struct mbuf *m0)
1134 {
1135 size_t len;
1136
1137 if ((m0->m_flags & M_PKTHDR) != 0) {
1138 len = m0->m_pkthdr.len;
1139 } else {
1140 struct mbuf *m;
1141
1142 for (m = m0, len = 0; m != NULL; m = m->m_next)
1143 len += m->m_len;
1144 }
1145 return (len);
1146 }
1147
1148
1149 /* ------------------------------------------------------------------------ */
1150 /* Function: ipf_pullup */
1151 /* Returns: NULL == pullup failed, else pointer to protocol header */
1152 /* Parameters: xmin(I)- pointer to buffer where data packet starts */
1153 /* fin(I) - pointer to packet information */
1154 /* len(I) - number of bytes to pullup */
1155 /* */
1156 /* Attempt to move at least len bytes (from the start of the buffer) into a */
1157 /* single buffer for ease of access. Operating system native functions are */
1158 /* used to manage buffers - if necessary. If the entire packet ends up in */
1159 /* a single buffer, set the FI_COALESCE flag even though ipf_coalesce() has */
1160 /* not been called. Both fin_ip and fin_dp are updated before exiting _IF_ */
1161 /* and ONLY if the pullup succeeds. */
1162 /* */
1163 /* We assume that 'xmin' is a pointer to a buffer that is part of the chain */
1164 /* of buffers that starts at *fin->fin_mp. */
1165 /* ------------------------------------------------------------------------ */
1166 ip_t *
ipf_pullup(mb_t * xmin,fr_info_t * fin,int len)1167 ipf_pullup(mb_t *xmin, fr_info_t *fin, int len)
1168 {
1169 int dpoff, ipoff;
1170 mb_t *m = xmin;
1171 ip_t *ip;
1172
1173 if (m == NULL)
1174 return (NULL);
1175
1176 ip = fin->fin_ip;
1177 if ((fin->fin_flx & FI_COALESCE) != 0)
1178 return (ip);
1179
1180 ipoff = fin->fin_ipoff;
1181 if (fin->fin_dp != NULL)
1182 dpoff = (char *)fin->fin_dp - (char *)ip;
1183 else
1184 dpoff = 0;
1185
1186 if (M_LEN(m) < len) {
1187 mb_t *n = *fin->fin_mp;
1188 /*
1189 * Assume that M_PKTHDR is set and just work with what is left
1190 * rather than check..
1191 * Should not make any real difference, anyway.
1192 */
1193 if (m != n) {
1194 /*
1195 * Record the mbuf that points to the mbuf that we're
1196 * about to go to work on so that we can update the
1197 * m_next appropriately later.
1198 */
1199 for (; n->m_next != m; n = n->m_next)
1200 ;
1201 } else {
1202 n = NULL;
1203 }
1204
1205 #ifdef MHLEN
1206 if (len > MHLEN)
1207 #else
1208 if (len > MLEN)
1209 #endif
1210 {
1211 #ifdef HAVE_M_PULLDOWN
1212 if (m_pulldown(m, 0, len, NULL) == NULL)
1213 m = NULL;
1214 #else
1215 FREE_MB_T(*fin->fin_mp);
1216 m = NULL;
1217 n = NULL;
1218 #endif
1219 } else
1220 {
1221
1222 m = m_pullup(m, len);
1223 }
1224 if (n != NULL)
1225 n->m_next = m;
1226 if (m == NULL) {
1227 /*
1228 * When n is non-NULL, it indicates that m pointed to
1229 * a sub-chain (tail) of the mbuf and that the head
1230 * of this chain has not yet been free'd.
1231 */
1232 if (n != NULL) {
1233 FREE_MB_T(*fin->fin_mp);
1234 }
1235
1236 *fin->fin_mp = NULL;
1237 fin->fin_m = NULL;
1238 return (NULL);
1239 }
1240
1241 if (n == NULL)
1242 *fin->fin_mp = m;
1243
1244 while (M_LEN(m) == 0) {
1245 m = m->m_next;
1246 }
1247 fin->fin_m = m;
1248 ip = MTOD(m, ip_t *) + ipoff;
1249
1250 fin->fin_ip = ip;
1251 if (fin->fin_dp != NULL)
1252 fin->fin_dp = (char *)fin->fin_ip + dpoff;
1253 if (fin->fin_fraghdr != NULL)
1254 fin->fin_fraghdr = (char *)ip +
1255 ((char *)fin->fin_fraghdr -
1256 (char *)fin->fin_ip);
1257 }
1258
1259 if (len == fin->fin_plen)
1260 fin->fin_flx |= FI_COALESCE;
1261 return (ip);
1262 }
1263
1264
1265 int
ipf_inject(fr_info_t * fin,mb_t * m)1266 ipf_inject(fr_info_t *fin, mb_t *m)
1267 {
1268 struct epoch_tracker et;
1269 int error = 0;
1270
1271 NET_EPOCH_ENTER(et);
1272 if (fin->fin_out == 0) {
1273 netisr_dispatch(NETISR_IP, m);
1274 } else {
1275 fin->fin_ip->ip_len = ntohs(fin->fin_ip->ip_len);
1276 fin->fin_ip->ip_off = ntohs(fin->fin_ip->ip_off);
1277 error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL);
1278 }
1279 NET_EPOCH_EXIT(et);
1280
1281 return (error);
1282 }
1283
1284 VNET_DEFINE_STATIC(pfil_hook_t, ipf_inet_hook);
1285 VNET_DEFINE_STATIC(pfil_hook_t, ipf_inet6_hook);
1286 #define V_ipf_inet_hook VNET(ipf_inet_hook)
1287 #define V_ipf_inet6_hook VNET(ipf_inet6_hook)
1288
ipf_pfil_unhook(void)1289 int ipf_pfil_unhook(void) {
1290
1291 pfil_remove_hook(V_ipf_inet_hook);
1292
1293 #ifdef USE_INET6
1294 pfil_remove_hook(V_ipf_inet6_hook);
1295 #endif
1296
1297 return (0);
1298 }
1299
ipf_pfil_hook(void)1300 int ipf_pfil_hook(void) {
1301 int error, error6;
1302
1303 struct pfil_hook_args pha = {
1304 .pa_version = PFIL_VERSION,
1305 .pa_flags = PFIL_IN | PFIL_OUT,
1306 .pa_modname = "ipfilter",
1307 .pa_rulname = "default-ip4",
1308 .pa_mbuf_chk = ipf_check_wrapper,
1309 .pa_type = PFIL_TYPE_IP4,
1310 };
1311 V_ipf_inet_hook = pfil_add_hook(&pha);
1312
1313 #ifdef USE_INET6
1314 pha.pa_rulname = "default-ip6";
1315 pha.pa_mbuf_chk = ipf_check_wrapper6;
1316 pha.pa_type = PFIL_TYPE_IP6;
1317 V_ipf_inet6_hook = pfil_add_hook(&pha);
1318 #endif
1319
1320 struct pfil_link_args pla = {
1321 .pa_version = PFIL_VERSION,
1322 .pa_flags = PFIL_IN | PFIL_OUT | PFIL_HEADPTR | PFIL_HOOKPTR,
1323 .pa_head = V_inet_pfil_head,
1324 .pa_hook = V_ipf_inet_hook,
1325 };
1326 error = pfil_link(&pla);
1327
1328 error6 = 0;
1329 #ifdef USE_INET6
1330 pla.pa_head = V_inet6_pfil_head;
1331 pla.pa_hook = V_ipf_inet6_hook;
1332 error6 = pfil_link(&pla);
1333 #endif
1334
1335 if (error || error6)
1336 error = ENODEV;
1337 else
1338 error = 0;
1339
1340 return (error);
1341 }
1342
1343 void
ipf_event_reg(void)1344 ipf_event_reg(void)
1345 {
1346 V_ipf_arrivetag = EVENTHANDLER_REGISTER(ifnet_arrival_event, \
1347 ipf_ifevent, NULL, \
1348 EVENTHANDLER_PRI_ANY);
1349 V_ipf_departtag = EVENTHANDLER_REGISTER(ifnet_departure_event, \
1350 ipf_ifevent, NULL, \
1351 EVENTHANDLER_PRI_ANY);
1352 }
1353
1354 void
ipf_event_dereg(void)1355 ipf_event_dereg(void)
1356 {
1357 if (V_ipf_arrivetag != NULL) {
1358 EVENTHANDLER_DEREGISTER(ifnet_arrival_event, V_ipf_arrivetag);
1359 }
1360 if (V_ipf_departtag != NULL) {
1361 EVENTHANDLER_DEREGISTER(ifnet_departure_event, V_ipf_departtag);
1362 }
1363 }
1364
1365
1366 u_32_t
ipf_random(void)1367 ipf_random(void)
1368 {
1369 return (arc4random());
1370 }
1371
1372
1373 u_int
ipf_pcksum(fr_info_t * fin,int hlen,u_int sum)1374 ipf_pcksum(fr_info_t *fin, int hlen, u_int sum)
1375 {
1376 struct mbuf *m;
1377 u_int sum2;
1378 int off;
1379
1380 m = fin->fin_m;
1381 off = (char *)fin->fin_dp - (char *)fin->fin_ip;
1382 m->m_data += hlen;
1383 m->m_len -= hlen;
1384 sum2 = in_cksum(fin->fin_m, fin->fin_plen - off);
1385 m->m_len += hlen;
1386 m->m_data -= hlen;
1387
1388 /*
1389 * Both sum and sum2 are partial sums, so combine them together.
1390 */
1391 sum += ~sum2 & 0xffff;
1392 while (sum > 0xffff)
1393 sum = (sum & 0xffff) + (sum >> 16);
1394 sum2 = ~sum & 0xffff;
1395 return (sum2);
1396 }
1397
1398 #ifdef USE_INET6
1399 u_int
ipf_pcksum6(struct mbuf * m,ip6_t * ip6,u_int32_t off,u_int32_t len)1400 ipf_pcksum6(struct mbuf *m, ip6_t *ip6, u_int32_t off, u_int32_t len)
1401 {
1402 #ifdef _KERNEL
1403 int sum;
1404
1405 if (m->m_len < sizeof(struct ip6_hdr)) {
1406 return (0xffff);
1407 }
1408
1409 sum = in6_cksum(m, ip6->ip6_nxt, off, len);
1410 return (sum);
1411 #else
1412 u_short *sp;
1413 u_int sum;
1414
1415 sp = (u_short *)&ip6->ip6_src;
1416 sum = *sp++; /* ip6_src */
1417 sum += *sp++;
1418 sum += *sp++;
1419 sum += *sp++;
1420 sum += *sp++;
1421 sum += *sp++;
1422 sum += *sp++;
1423 sum += *sp++;
1424 sum += *sp++; /* ip6_dst */
1425 sum += *sp++;
1426 sum += *sp++;
1427 sum += *sp++;
1428 sum += *sp++;
1429 sum += *sp++;
1430 sum += *sp++;
1431 sum += *sp++;
1432 return (ipf_pcksum(fin, off, sum));
1433 #endif
1434 }
1435 #endif
1436
1437 void
ipf_fbsd_kenv_get(ipf_main_softc_t * softc)1438 ipf_fbsd_kenv_get(ipf_main_softc_t *softc)
1439 {
1440 TUNABLE_INT_FETCH("net.inet.ipf.large_nat",
1441 &softc->ipf_large_nat);
1442 }
1443