xref: /netbsd-src/sys/net/npf/npf_impl.h (revision e6c7e151de239c49d2e38720a061ed9d1fa99309)
1 /*-
2  * Copyright (c) 2009-2019 The NetBSD Foundation, Inc.
3  * All rights reserved.
4  *
5  * This material is based upon work partially supported by The
6  * NetBSD Foundation under a contract with Mindaugas Rasiukevicius.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * Private NPF structures and interfaces.
32  * For internal use within NPF core only.
33  */
34 
35 #ifndef _NPF_IMPL_H_
36 #define _NPF_IMPL_H_
37 
38 #if !defined(_KERNEL) && !defined(_NPF_STANDALONE)
39 #error "Kernel-level header only"
40 #endif
41 
42 #ifdef _KERNEL_OPT
43 /* For INET/INET6 definitions. */
44 #include "opt_inet.h"
45 #include "opt_inet6.h"
46 #endif
47 
48 #ifdef _KERNEL
49 #include <sys/types.h>
50 #include <sys/queue.h>
51 
52 #include <net/bpf.h>
53 #include <net/bpfjit.h>
54 #include <net/if.h>
55 #endif
56 #include <dnv.h>
57 #include <nv.h>
58 
59 #include "npf.h"
60 #include "npfkern.h"
61 
62 #ifdef _NPF_DEBUG
63 #define	NPF_PRINTF(x)	printf x
64 #else
65 #define	NPF_PRINTF(x)
66 #endif
67 
68 /*
69  * STRUCTURE DECLARATIONS.
70  */
71 
72 struct npf_ruleset;
73 struct npf_rule;
74 struct npf_rprocset;
75 struct npf_portmap;
76 struct npf_nat;
77 struct npf_conn;
78 
79 typedef struct npf_ruleset	npf_ruleset_t;
80 typedef struct npf_rule		npf_rule_t;
81 typedef struct npf_portmap	npf_portmap_t;
82 typedef struct npf_nat		npf_nat_t;
83 typedef struct npf_rprocset	npf_rprocset_t;
84 typedef struct npf_alg		npf_alg_t;
85 typedef struct npf_natpolicy	npf_natpolicy_t;
86 typedef struct npf_conn		npf_conn_t;
87 
88 struct npf_conndb;
89 struct npf_table;
90 struct npf_tableset;
91 struct npf_algset;
92 struct npf_ifmap;
93 
94 typedef struct npf_conndb	npf_conndb_t;
95 typedef struct npf_table	npf_table_t;
96 typedef struct npf_tableset	npf_tableset_t;
97 typedef struct npf_algset	npf_algset_t;
98 
99 #ifdef __NetBSD__
100 typedef void			ebr_t;
101 #endif
102 
103 /*
104  * DEFINITIONS.
105  */
106 
107 typedef struct {
108 	npf_ruleset_t *		ruleset;
109 	npf_ruleset_t *		nat_ruleset;
110 	npf_rprocset_t *	rule_procs;
111 	npf_tableset_t *	tableset;
112 	bool			default_pass;
113 } npf_config_t;
114 
115 typedef void (*npf_workfunc_t)(npf_t *);
116 
117 typedef struct {
118 	uint64_t	mi_rid;
119 	unsigned	mi_retfl;
120 	unsigned	mi_di;
121 } npf_match_info_t;
122 
123 /*
124  * Some artificial limits.
125  * Note: very unlikely to have many ALGs.
126  */
127 #define	NPF_MAX_RULES		(1024 * 1024)
128 #define	NPF_MAX_TABLES		128
129 #define	NPF_MAX_RPROCS		128
130 #define	NPF_MAX_IFMAP		64
131 #define	NPF_MAX_ALGS		4
132 #define	NPF_MAX_WORKS		4
133 
134 /*
135  * CONNECTION STATE STRUCTURES
136  */
137 
138 #define	NPF_FLOW_FORW		0
139 #define	NPF_FLOW_BACK		1
140 
141 typedef struct {
142 	uint32_t	nst_end;
143 	uint32_t	nst_maxend;
144 	uint32_t	nst_maxwin;
145 	int		nst_wscale;
146 } npf_tcpstate_t;
147 
148 typedef struct {
149 	unsigned 	nst_state;
150 	npf_tcpstate_t	nst_tcpst[2];
151 } npf_state_t;
152 
153 /*
154  * ALG FUNCTIONS.
155  */
156 
157 typedef struct {
158 	bool		(*match)(npf_cache_t *, npf_nat_t *, int);
159 	bool		(*translate)(npf_cache_t *, npf_nat_t *, bool);
160 	npf_conn_t *	(*inspect)(npf_cache_t *, int);
161 } npfa_funcs_t;
162 
163 /*
164  * NBUF STRUCTURE.
165  */
166 
167 struct nbuf {
168 	struct mbuf *	nb_mbuf0;
169 	struct mbuf *	nb_mbuf;
170 	void *		nb_nptr;
171 	const ifnet_t *	nb_ifp;
172 	unsigned	nb_ifid;
173 	int		nb_flags;
174 	const npf_mbufops_t *nb_mops;
175 };
176 
177 /*
178  * PARAMS.
179  */
180 
181 typedef struct npf_paraminfo npf_paraminfo_t;
182 
183 typedef struct {
184 	const char *	name;
185 	int *		valp;
186 	int		default_val;
187 	/*
188 	 * Minimum and maximum allowed values (inclusive).
189 	 */
190 	int		min;
191 	int		max;
192 } npf_param_t;
193 
194 typedef enum {
195 	NPF_PARAMS_CONNDB = 0,
196 	NPF_PARAMS_GENERIC_STATE,
197 	NPF_PARAMS_TCP_STATE,
198 	NPF_PARAMS_COUNT
199 } npf_paramgroup_t;
200 
201 /*
202  * NPF INSTANCE (CONTEXT) STRUCTURE AND AUXILIARY OPERATIONS.
203  */
204 
205 struct npf {
206 	/* Active NPF configuration. */
207 	kmutex_t		config_lock;
208 	ebr_t *			ebr;
209 	npf_config_t *		config;
210 
211 	/* BPF byte-code context. */
212 	bpf_ctx_t *		bpfctx;
213 	const npf_mbufops_t *	mbufops;
214 
215 	/* Parameters. */
216 	npf_paraminfo_t *	paraminfo;
217 	void *			params[NPF_PARAMS_COUNT];
218 
219 	/*
220 	 * Connection tracking state: disabled (off) or enabled (on).
221 	 * Connection tracking database, connection cache and the lock.
222 	 * There are two caches (pools): for IPv4 and IPv6.
223 	 */
224 	volatile int		conn_tracking;
225 	kmutex_t		conn_lock;
226 	npf_conndb_t *		conn_db;
227 	pool_cache_t		conn_cache[2];
228 
229 	/* NAT and ALGs. */
230 	npf_portmap_t *		portmap;
231 	npf_algset_t *		algset;
232 
233 	/* Interface mapping. */
234 	const npf_ifops_t *	ifops;
235 	struct npf_ifmap *	ifmap;
236 	unsigned		ifmap_cnt;
237 	unsigned		ifmap_off;
238 	kmutex_t		ifmap_lock;
239 
240 	/* Associated worker thread. */
241 	unsigned		worker_id;
242 	void *			worker_entry;
243 	bool			sync_registered;
244 
245 	/* List of extensions and its lock. */
246 	LIST_HEAD(, npf_ext)	ext_list;
247 	kmutex_t		ext_lock;
248 
249 	/* Statistics. */
250 	percpu_t *		stats_percpu;
251 };
252 
253 /*
254  * NPF extensions and rule procedure interface.
255  */
256 
257 struct npf_rproc;
258 typedef struct npf_rproc npf_rproc_t;
259 
260 typedef struct {
261 	u_int	version;
262 	void *	ctx;
263 	int	(*ctor)(npf_rproc_t *, const nvlist_t *);
264 	void	(*dtor)(npf_rproc_t *, void *);
265 	bool	(*proc)(npf_cache_t *, void *, const npf_match_info_t *, int *);
266 } npf_ext_ops_t;
267 
268 void *		npf_ext_register(npf_t *, const char *, const npf_ext_ops_t *);
269 int		npf_ext_unregister(npf_t *, void *);
270 void		npf_rproc_assign(npf_rproc_t *, void *);
271 
272 /*
273  * INTERFACES.
274  */
275 
276 /* NPF config, statistics, etc. */
277 void		npf_config_init(npf_t *);
278 void		npf_config_fini(npf_t *);
279 
280 npf_config_t *	npf_config_enter(npf_t *);
281 void		npf_config_exit(npf_t *);
282 void		npf_config_sync(npf_t *);
283 bool		npf_config_locked_p(npf_t *);
284 int		npf_config_read_enter(npf_t *);
285 void		npf_config_read_exit(npf_t *, int);
286 
287 npf_config_t *	npf_config_create(void);
288 void		npf_config_destroy(npf_config_t *);
289 void		npf_config_load(npf_t *, npf_config_t *, npf_conndb_t *, bool);
290 npf_ruleset_t *	npf_config_ruleset(npf_t *npf);
291 npf_ruleset_t *	npf_config_natset(npf_t *npf);
292 npf_tableset_t *npf_config_tableset(npf_t *npf);
293 bool		npf_default_pass(npf_t *);
294 bool		npf_active_p(void);
295 
296 int		npf_worker_sysinit(unsigned);
297 void		npf_worker_sysfini(void);
298 void		npf_worker_signal(npf_t *);
299 void		npf_worker_register(npf_t *, npf_workfunc_t);
300 void		npf_worker_unregister(npf_t *, npf_workfunc_t);
301 
302 int		npfctl_save(npf_t *, u_long, void *);
303 int		npfctl_load(npf_t *, u_long, void *);
304 int		npfctl_rule(npf_t *, u_long, void *);
305 int		npfctl_conn_lookup(npf_t *, u_long, void *);
306 int		npfctl_table_replace(npf_t *, u_long, void *);
307 int		npfctl_table(npf_t *, void *);
308 
309 void		npf_stats_inc(npf_t *, npf_stats_t);
310 void		npf_stats_dec(npf_t *, npf_stats_t);
311 
312 void		npf_param_init(npf_t *);
313 void		npf_param_fini(npf_t *);
314 void		npf_param_register(npf_t *, npf_param_t *, unsigned);
315 void *		npf_param_allocgroup(npf_t *, npf_paramgroup_t, size_t);
316 void		npf_param_freegroup(npf_t *, npf_paramgroup_t, size_t);
317 int		npf_param_check(npf_t *, const char *, int);
318 
319 void		npf_ifmap_init(npf_t *, const npf_ifops_t *);
320 void		npf_ifmap_fini(npf_t *);
321 u_int		npf_ifmap_register(npf_t *, const char *);
322 void		npf_ifmap_flush(npf_t *);
323 u_int		npf_ifmap_getid(npf_t *, const ifnet_t *);
324 void		npf_ifmap_copylogname(npf_t *, unsigned, char *, size_t);
325 void		npf_ifmap_copyname(npf_t *, unsigned, char *, size_t);
326 
327 void		npf_ifaddr_sync(npf_t *, ifnet_t *);
328 void		npf_ifaddr_flush(npf_t *, ifnet_t *);
329 void		npf_ifaddr_syncall(npf_t *);
330 
331 /* Protocol helpers. */
332 int		npf_cache_all(npf_cache_t *);
333 void		npf_recache(npf_cache_t *);
334 
335 bool		npf_rwrip(const npf_cache_t *, u_int, const npf_addr_t *);
336 bool		npf_rwrport(const npf_cache_t *, u_int, const in_port_t);
337 bool		npf_rwrcksum(const npf_cache_t *, u_int,
338 		    const npf_addr_t *, const in_port_t);
339 int		npf_napt_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
340 		    const in_addr_t);
341 int		npf_npt66_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
342 		    npf_netmask_t, uint16_t);
343 
344 uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
345 uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
346 uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
347 		    const npf_addr_t *);
348 uint32_t	npf_addr_mix(const int, const npf_addr_t *, const npf_addr_t *);
349 int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
350 		    const npf_addr_t *, const npf_netmask_t, const int);
351 void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
352 		    const int, npf_addr_t *);
353 void		npf_addr_bitor(const npf_addr_t *, const npf_netmask_t,
354 		    const int, npf_addr_t *);
355 int		npf_netmask_check(const int, npf_netmask_t);
356 
357 int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
358 		    uint32_t *);
359 bool		npf_fetch_tcpopts(npf_cache_t *, uint16_t *, int *);
360 bool		npf_set_mss(npf_cache_t *, uint16_t, uint16_t *, uint16_t *,
361 		    bool *);
362 bool		npf_return_block(npf_cache_t *, const int);
363 
364 /* BPF interface. */
365 void		npf_bpf_sysinit(void);
366 void		npf_bpf_sysfini(void);
367 void		npf_bpf_prepare(npf_cache_t *, bpf_args_t *, uint32_t *);
368 int		npf_bpf_filter(bpf_args_t *, const void *, bpfjit_func_t);
369 void *		npf_bpf_compile(void *, size_t);
370 bool		npf_bpf_validate(const void *, size_t);
371 
372 /* Tableset interface. */
373 void		npf_tableset_sysinit(void);
374 void		npf_tableset_sysfini(void);
375 
376 npf_tableset_t *npf_tableset_create(u_int);
377 void		npf_tableset_destroy(npf_tableset_t *);
378 int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
379 npf_table_t *	npf_tableset_getbyname(npf_tableset_t *, const char *);
380 npf_table_t *	npf_tableset_getbyid(npf_tableset_t *, u_int);
381 npf_table_t *	npf_tableset_swap(npf_tableset_t *, npf_table_t *);
382 void		npf_tableset_reload(npf_t *, npf_tableset_t *, npf_tableset_t *);
383 int		npf_tableset_export(npf_t *, const npf_tableset_t *, nvlist_t *);
384 
385 npf_table_t *	npf_table_create(const char *, u_int, int, const void *, size_t);
386 void		npf_table_destroy(npf_table_t *);
387 
388 u_int		npf_table_getid(npf_table_t *);
389 int		npf_table_check(npf_tableset_t *, const char *, uint64_t, uint64_t, bool);
390 int		npf_table_insert(npf_table_t *, const int,
391 		    const npf_addr_t *, const npf_netmask_t);
392 int		npf_table_remove(npf_table_t *, const int,
393 		    const npf_addr_t *, const npf_netmask_t);
394 int		npf_table_lookup(npf_table_t *, const int, const npf_addr_t *);
395 npf_addr_t *	npf_table_getsome(npf_table_t *, const int, unsigned);
396 int		npf_table_list(npf_table_t *, void *, size_t);
397 int		npf_table_flush(npf_table_t *);
398 void		npf_table_gc(npf_t *, npf_table_t *);
399 
400 /* Ruleset interface. */
401 npf_ruleset_t *	npf_ruleset_create(size_t);
402 void		npf_ruleset_destroy(npf_ruleset_t *);
403 void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
404 void		npf_ruleset_reload(npf_t *, npf_ruleset_t *,
405 		    npf_ruleset_t *, bool);
406 npf_natpolicy_t *npf_ruleset_findnat(npf_ruleset_t *, uint64_t);
407 void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
408 int		npf_ruleset_export(npf_t *, const npf_ruleset_t *,
409 		    const char *, nvlist_t *);
410 
411 npf_rule_t *	npf_ruleset_lookup(npf_ruleset_t *, const char *);
412 int		npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
413 int		npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
414 int		npf_ruleset_remkey(npf_ruleset_t *, const char *,
415 		    const void *, size_t);
416 nvlist_t *	npf_ruleset_list(npf_t *, npf_ruleset_t *, const char *);
417 int		npf_ruleset_flush(npf_ruleset_t *, const char *);
418 void		npf_ruleset_gc(npf_ruleset_t *);
419 
420 npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, const npf_ruleset_t *,
421 		    const int, const int);
422 int		npf_rule_conclude(const npf_rule_t *, npf_match_info_t *);
423 
424 /* Rule interface. */
425 npf_rule_t *	npf_rule_alloc(npf_t *, const nvlist_t *);
426 void		npf_rule_setcode(npf_rule_t *, int, void *, size_t);
427 void		npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
428 void		npf_rule_free(npf_rule_t *);
429 uint64_t	npf_rule_getid(const npf_rule_t *);
430 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
431 void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
432 npf_rproc_t *	npf_rule_getrproc(const npf_rule_t *);
433 
434 void		npf_ext_init(npf_t *);
435 void		npf_ext_fini(npf_t *);
436 int		npf_ext_construct(npf_t *, const char *,
437 		    npf_rproc_t *, const nvlist_t *);
438 
439 npf_rprocset_t *npf_rprocset_create(void);
440 void		npf_rprocset_destroy(npf_rprocset_t *);
441 npf_rproc_t *	npf_rprocset_lookup(npf_rprocset_t *, const char *);
442 void		npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
443 int		npf_rprocset_export(const npf_rprocset_t *, nvlist_t *);
444 
445 npf_rproc_t *	npf_rproc_create(const nvlist_t *);
446 void		npf_rproc_acquire(npf_rproc_t *);
447 void		npf_rproc_release(npf_rproc_t *);
448 const char *	npf_rproc_getname(const npf_rproc_t *);
449 bool		npf_rproc_run(npf_cache_t *, npf_rproc_t *,
450 		    const npf_match_info_t *, int *);
451 
452 /* State handling. */
453 void		npf_state_sysinit(npf_t *);
454 void		npf_state_sysfini(npf_t *);
455 
456 bool		npf_state_init(npf_cache_t *, npf_state_t *);
457 bool		npf_state_inspect(npf_cache_t *, npf_state_t *, const bool);
458 int		npf_state_etime(npf_t *, const npf_state_t *, const int);
459 void		npf_state_destroy(npf_state_t *);
460 
461 void		npf_state_tcp_sysinit(npf_t *);
462 void		npf_state_tcp_sysfini(npf_t *);
463 bool		npf_state_tcp(npf_cache_t *, npf_state_t *, int);
464 int		npf_state_tcp_timeout(npf_t *, const npf_state_t *);
465 
466 /* Portmap. */
467 void		npf_portmap_init(npf_t *);
468 void		npf_portmap_fini(npf_t *);
469 
470 npf_portmap_t *	npf_portmap_create(int, int);
471 void		npf_portmap_destroy(npf_portmap_t *);
472 
473 in_port_t	npf_portmap_get(npf_portmap_t *, int, const npf_addr_t *);
474 bool		npf_portmap_take(npf_portmap_t *, int, const npf_addr_t *, in_port_t);
475 void		npf_portmap_put(npf_portmap_t *, int, const npf_addr_t *, in_port_t);
476 void		npf_portmap_flush(npf_portmap_t *);
477 
478 /* NAT. */
479 void		npf_nat_sysinit(void);
480 void		npf_nat_sysfini(void);
481 npf_natpolicy_t *npf_nat_newpolicy(npf_t *, const nvlist_t *, npf_ruleset_t *);
482 int		npf_nat_policyexport(const npf_natpolicy_t *, nvlist_t *);
483 void		npf_nat_freepolicy(npf_natpolicy_t *);
484 bool		npf_nat_cmppolicy(npf_natpolicy_t *, npf_natpolicy_t *);
485 void		npf_nat_setid(npf_natpolicy_t *, uint64_t);
486 uint64_t	npf_nat_getid(const npf_natpolicy_t *);
487 void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
488 
489 int		npf_do_nat(npf_cache_t *, npf_conn_t *, const int);
490 void		npf_nat_destroy(npf_nat_t *);
491 void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
492 void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
493 void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
494 
495 void		npf_nat_export(nvlist_t *, npf_nat_t *);
496 npf_nat_t *	npf_nat_import(npf_t *, const nvlist_t *, npf_ruleset_t *,
497 		    npf_conn_t *);
498 
499 /* ALG interface. */
500 void		npf_alg_sysinit(void);
501 void		npf_alg_sysfini(void);
502 void		npf_alg_init(npf_t *);
503 void		npf_alg_fini(npf_t *);
504 npf_alg_t *	npf_alg_register(npf_t *, const char *, const npfa_funcs_t *);
505 int		npf_alg_unregister(npf_t *, npf_alg_t *);
506 npf_alg_t *	npf_alg_construct(npf_t *, const char *);
507 bool		npf_alg_match(npf_cache_t *, npf_nat_t *, int);
508 void		npf_alg_exec(npf_cache_t *, npf_nat_t *, bool);
509 npf_conn_t *	npf_alg_conn(npf_cache_t *, int);
510 int		npf_alg_export(npf_t *, nvlist_t *);
511 
512 /* Wrappers for the reclamation mechanism. */
513 ebr_t *		npf_ebr_create(void);
514 void		npf_ebr_destroy(ebr_t *);
515 void		npf_ebr_register(ebr_t *);
516 void		npf_ebr_unregister(ebr_t *);
517 int		npf_ebr_enter(ebr_t *);
518 void		npf_ebr_exit(ebr_t *, int);
519 void		npf_ebr_full_sync(ebr_t *);
520 bool		npf_ebr_incrit_p(ebr_t *);
521 
522 /* Debugging routines. */
523 const char *	npf_addr_dump(const npf_addr_t *, int);
524 void		npf_state_dump(const npf_state_t *);
525 void		npf_nat_dump(const npf_nat_t *);
526 void		npf_ruleset_dump(npf_t *, const char *);
527 void		npf_state_setsampler(void (*)(npf_state_t *, bool));
528 
529 /* In-kernel routines. */
530 void		npf_setkernctx(npf_t *);
531 npf_t *		npf_getkernctx(void);
532 
533 #endif	/* _NPF_IMPL_H_ */
534