xref: /netbsd-src/sys/net/npf/npf_impl.h (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*-
2  * Copyright (c) 2009-2014 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_nat;
76 struct npf_conn;
77 struct npf_config;
78 
79 typedef struct npf_ruleset	npf_ruleset_t;
80 typedef struct npf_rule		npf_rule_t;
81 typedef struct npf_nat		npf_nat_t;
82 typedef struct npf_rprocset	npf_rprocset_t;
83 typedef struct npf_alg		npf_alg_t;
84 typedef struct npf_natpolicy	npf_natpolicy_t;
85 typedef struct npf_conn		npf_conn_t;
86 typedef struct npf_config	npf_config_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 /*
100  * DEFINITIONS.
101  */
102 
103 typedef void (*npf_workfunc_t)(npf_t *);
104 
105 typedef struct {
106 	uint64_t	mi_rid;
107 	unsigned	mi_retfl;
108 	unsigned	mi_di;
109 } npf_match_info_t;
110 
111 /*
112  * Some artificial limits.
113  * Note: very unlikely to have many ALGs.
114  */
115 #define	NPF_MAX_RULES		(1024 * 1024)
116 #define	NPF_MAX_TABLES		128
117 #define	NPF_MAX_RPROCS		128
118 #define	NPF_MAX_IFMAP		64
119 #define	NPF_MAX_ALGS		4
120 #define	NPF_MAX_WORKS		4
121 
122 /*
123  * CONNECTION STATE STRUCTURES
124  */
125 
126 #define	NPF_FLOW_FORW		0
127 #define	NPF_FLOW_BACK		1
128 
129 typedef struct {
130 	uint32_t	nst_end;
131 	uint32_t	nst_maxend;
132 	uint32_t	nst_maxwin;
133 	int		nst_wscale;
134 } npf_tcpstate_t;
135 
136 typedef struct {
137 	u_int		nst_state;
138 	npf_tcpstate_t	nst_tcpst[2];
139 } npf_state_t;
140 
141 /*
142  * ALG FUNCTIONS.
143  */
144 
145 typedef struct {
146 	bool		(*match)(npf_cache_t *, npf_nat_t *, int);
147 	bool		(*translate)(npf_cache_t *, npf_nat_t *, bool);
148 	npf_conn_t *	(*inspect)(npf_cache_t *, int);
149 } npfa_funcs_t;
150 
151 /*
152  * NBUF STRUCTURE.
153  */
154 
155 struct nbuf {
156 	struct mbuf *	nb_mbuf0;
157 	struct mbuf *	nb_mbuf;
158 	void *		nb_nptr;
159 	const ifnet_t *	nb_ifp;
160 	unsigned	nb_ifid;
161 	int		nb_flags;
162 	const npf_mbufops_t *nb_mops;
163 };
164 
165 /*
166  * NPF INSTANCE (CONTEXT) STRUCTURE AND AUXILIARY OPERATIONS.
167  */
168 
169 struct npf {
170 	/* Active NPF configuration. */
171 	kmutex_t		config_lock;
172 	pserialize_t		qsbr;
173 	npf_config_t *		config;
174 
175 	/* BPF byte-code context. */
176 	bpf_ctx_t *		bpfctx;
177 	const npf_mbufops_t *	mbufops;
178 
179 	/*
180 	 * Connection tracking state: disabled (off) or enabled (on).
181 	 * Connection tracking database, connection cache and the lock.
182 	 */
183 	volatile int		conn_tracking;
184 	kmutex_t		conn_lock;
185 	npf_conndb_t *		conn_db;
186 	pool_cache_t		conn_cache;
187 
188 	/* ALGs. */
189 	npf_algset_t *		algset;
190 
191 	/* Interface mapping. */
192 	const npf_ifops_t *	ifops;
193 	struct npf_ifmap *	ifmap;
194 	unsigned		ifmap_cnt;
195 
196 	/* Associated worker thread. */
197 	unsigned		worker_id;
198 	void *			worker_entry;
199 	bool			sync_registered;
200 
201 	/* List of extensions and its lock. */
202 	LIST_HEAD(, npf_ext)	ext_list;
203 	kmutex_t		ext_lock;
204 
205 	/* Statistics. */
206 	percpu_t *		stats_percpu;
207 };
208 
209 
210 /*
211  * NPF extensions and rule procedure interface.
212  */
213 
214 struct npf_rproc;
215 typedef struct npf_rproc npf_rproc_t;
216 
217 typedef struct {
218 	u_int	version;
219 	void *	ctx;
220 	int	(*ctor)(npf_rproc_t *, const nvlist_t *);
221 	void	(*dtor)(npf_rproc_t *, void *);
222 	bool	(*proc)(npf_cache_t *, void *, const npf_match_info_t *, int *);
223 } npf_ext_ops_t;
224 
225 void *		npf_ext_register(npf_t *, const char *, const npf_ext_ops_t *);
226 int		npf_ext_unregister(npf_t *, void *);
227 void		npf_rproc_assign(npf_rproc_t *, void *);
228 
229 /*
230  * INTERFACES.
231  */
232 
233 /* NPF config, statistics, etc. */
234 void		npf_config_init(npf_t *);
235 void		npf_config_fini(npf_t *);
236 
237 void		npf_config_enter(npf_t *);
238 void		npf_config_exit(npf_t *);
239 void		npf_config_sync(npf_t *);
240 bool		npf_config_locked_p(npf_t *);
241 int		npf_config_read_enter(void);
242 void		npf_config_read_exit(int s);
243 
244 void		npf_config_load(npf_t *, npf_ruleset_t *, npf_tableset_t *,
245 		    npf_ruleset_t *, npf_rprocset_t *, npf_conndb_t *, bool);
246 npf_ruleset_t *	npf_config_ruleset(npf_t *npf);
247 npf_ruleset_t *	npf_config_natset(npf_t *npf);
248 npf_tableset_t *npf_config_tableset(npf_t *npf);
249 npf_rprocset_t *npf_config_rprocs(npf_t *);
250 bool		npf_default_pass(npf_t *);
251 
252 int		npf_worker_sysinit(unsigned);
253 void		npf_worker_sysfini(void);
254 void		npf_worker_signal(npf_t *);
255 void		npf_worker_register(npf_t *, npf_workfunc_t);
256 void		npf_worker_unregister(npf_t *, npf_workfunc_t);
257 
258 int		npfctl_switch(void *);
259 int		npfctl_reload(u_long, void *);
260 int		npfctl_save(npf_t *, u_long, void *);
261 int		npfctl_load(npf_t *, u_long, void *);
262 int		npfctl_rule(npf_t *, u_long, void *);
263 int		npfctl_conn_lookup(npf_t *, u_long, void *);
264 int		npfctl_table(npf_t *, void *);
265 
266 void		npf_stats_inc(npf_t *, npf_stats_t);
267 void		npf_stats_dec(npf_t *, npf_stats_t);
268 
269 void		npf_ifmap_init(npf_t *, const npf_ifops_t *);
270 void		npf_ifmap_fini(npf_t *);
271 u_int		npf_ifmap_register(npf_t *, const char *);
272 void		npf_ifmap_flush(npf_t *);
273 u_int		npf_ifmap_getid(npf_t *, const ifnet_t *);
274 const char *	npf_ifmap_getname(npf_t *, const u_int);
275 void		npf_ifmap_copyname(npf_t *, u_int, char *, size_t);
276 
277 void		npf_ifaddr_sync(npf_t *, ifnet_t *);
278 void		npf_ifaddr_flush(npf_t *, ifnet_t *);
279 void		npf_ifaddr_syncall(npf_t *);
280 
281 /* Packet filter hooks. */
282 int		npf_pfil_register(bool);
283 void		npf_pfil_unregister(bool);
284 bool		npf_pfil_registered_p(void);
285 
286 /* Protocol helpers. */
287 int		npf_cache_all(npf_cache_t *);
288 void		npf_recache(npf_cache_t *);
289 
290 bool		npf_rwrip(const npf_cache_t *, u_int, const npf_addr_t *);
291 bool		npf_rwrport(const npf_cache_t *, u_int, const in_port_t);
292 bool		npf_rwrcksum(const npf_cache_t *, u_int,
293 		    const npf_addr_t *, const in_port_t);
294 int		npf_napt_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
295 		    const in_addr_t);
296 int		npf_npt66_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
297 		    npf_netmask_t, uint16_t);
298 
299 uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
300 uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
301 uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
302 		    const npf_addr_t *);
303 uint32_t	npf_addr_mix(const int, const npf_addr_t *, const npf_addr_t *);
304 int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
305 		    const npf_addr_t *, const npf_netmask_t, const int);
306 void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
307 		    const int, npf_addr_t *);
308 void		npf_addr_bitor(const npf_addr_t *, const npf_netmask_t,
309 		    const int, npf_addr_t *);
310 
311 int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
312 		    uint32_t *);
313 bool		npf_fetch_tcpopts(npf_cache_t *, uint16_t *, int *);
314 bool		npf_set_mss(npf_cache_t *, uint16_t, uint16_t *, uint16_t *,
315 		    bool *);
316 bool		npf_return_block(npf_cache_t *, const int);
317 
318 /* BPF interface. */
319 void		npf_bpf_sysinit(void);
320 void		npf_bpf_sysfini(void);
321 void		npf_bpf_prepare(npf_cache_t *, bpf_args_t *, uint32_t *);
322 int		npf_bpf_filter(bpf_args_t *, const void *, bpfjit_func_t);
323 void *		npf_bpf_compile(void *, size_t);
324 bool		npf_bpf_validate(const void *, size_t);
325 
326 /* Tableset interface. */
327 void		npf_tableset_sysinit(void);
328 void		npf_tableset_sysfini(void);
329 
330 npf_tableset_t *npf_tableset_create(u_int);
331 void		npf_tableset_destroy(npf_tableset_t *);
332 int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
333 npf_table_t *	npf_tableset_getbyname(npf_tableset_t *, const char *);
334 npf_table_t *	npf_tableset_getbyid(npf_tableset_t *, u_int);
335 npf_table_t *	npf_tableset_swap(npf_tableset_t *, npf_table_t *);
336 void		npf_tableset_reload(npf_t *, npf_tableset_t *, npf_tableset_t *);
337 int		npf_tableset_export(npf_t *, const npf_tableset_t *, nvlist_t *);
338 
339 npf_table_t *	npf_table_create(const char *, u_int, int, const void *, size_t);
340 void		npf_table_destroy(npf_table_t *);
341 
342 u_int		npf_table_getid(npf_table_t *);
343 int		npf_table_check(npf_tableset_t *, const char *, uint64_t, uint64_t);
344 int		npf_table_insert(npf_table_t *, const int,
345 		    const npf_addr_t *, const npf_netmask_t);
346 int		npf_table_remove(npf_table_t *, const int,
347 		    const npf_addr_t *, const npf_netmask_t);
348 int		npf_table_lookup(npf_table_t *, const int, const npf_addr_t *);
349 npf_addr_t *	npf_table_getsome(npf_table_t *, const int, unsigned);
350 int		npf_table_list(npf_table_t *, void *, size_t);
351 int		npf_table_flush(npf_table_t *);
352 void		npf_table_gc(npf_t *, npf_table_t *);
353 
354 /* Ruleset interface. */
355 npf_ruleset_t *	npf_ruleset_create(size_t);
356 void		npf_ruleset_destroy(npf_ruleset_t *);
357 void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
358 void		npf_ruleset_reload(npf_t *, npf_ruleset_t *,
359 		    npf_ruleset_t *, bool);
360 npf_rule_t *	npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
361 npf_natpolicy_t *npf_ruleset_findnat(npf_ruleset_t *, uint64_t);
362 void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
363 int		npf_ruleset_export(npf_t *, const npf_ruleset_t *,
364 		    const char *, nvlist_t *);
365 
366 npf_rule_t *	npf_ruleset_lookup(npf_ruleset_t *, const char *);
367 int		npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
368 int		npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
369 int		npf_ruleset_remkey(npf_ruleset_t *, const char *,
370 		    const void *, size_t);
371 nvlist_t *	npf_ruleset_list(npf_t *, npf_ruleset_t *, const char *);
372 int		npf_ruleset_flush(npf_ruleset_t *, const char *);
373 void		npf_ruleset_gc(npf_ruleset_t *);
374 
375 npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, const npf_ruleset_t *,
376 		    const int, const int);
377 int		npf_rule_conclude(const npf_rule_t *, npf_match_info_t *);
378 
379 /* Rule interface. */
380 npf_rule_t *	npf_rule_alloc(npf_t *, const nvlist_t *);
381 void		npf_rule_setcode(npf_rule_t *, int, void *, size_t);
382 void		npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
383 void		npf_rule_free(npf_rule_t *);
384 uint64_t	npf_rule_getid(const npf_rule_t *);
385 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
386 void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
387 npf_rproc_t *	npf_rule_getrproc(const npf_rule_t *);
388 
389 void		npf_ext_init(npf_t *);
390 void		npf_ext_fini(npf_t *);
391 int		npf_ext_construct(npf_t *, const char *,
392 		    npf_rproc_t *, const nvlist_t *);
393 
394 npf_rprocset_t *npf_rprocset_create(void);
395 void		npf_rprocset_destroy(npf_rprocset_t *);
396 npf_rproc_t *	npf_rprocset_lookup(npf_rprocset_t *, const char *);
397 void		npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
398 int		npf_rprocset_export(const npf_rprocset_t *, nvlist_t *);
399 
400 npf_rproc_t *	npf_rproc_create(const nvlist_t *);
401 void		npf_rproc_acquire(npf_rproc_t *);
402 void		npf_rproc_release(npf_rproc_t *);
403 const char *	npf_rproc_getname(const npf_rproc_t *);
404 bool		npf_rproc_run(npf_cache_t *, npf_rproc_t *,
405 		    const npf_match_info_t *, int *);
406 
407 /* State handling. */
408 bool		npf_state_init(npf_cache_t *, npf_state_t *);
409 bool		npf_state_inspect(npf_cache_t *, npf_state_t *, const bool);
410 int		npf_state_etime(const npf_state_t *, const int);
411 void		npf_state_destroy(npf_state_t *);
412 
413 bool		npf_state_tcp(npf_cache_t *, npf_state_t *, int);
414 int		npf_state_tcp_timeout(const npf_state_t *);
415 
416 /* NAT. */
417 void		npf_nat_sysinit(void);
418 void		npf_nat_sysfini(void);
419 npf_natpolicy_t *npf_nat_newpolicy(npf_t *, const nvlist_t *, npf_ruleset_t *);
420 int		npf_nat_policyexport(const npf_natpolicy_t *, nvlist_t *);
421 void		npf_nat_freepolicy(npf_natpolicy_t *);
422 bool		npf_nat_cmppolicy(npf_natpolicy_t *, npf_natpolicy_t *);
423 bool		npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
424 void		npf_nat_setid(npf_natpolicy_t *, uint64_t);
425 uint64_t	npf_nat_getid(const npf_natpolicy_t *);
426 void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
427 
428 int		npf_do_nat(npf_cache_t *, npf_conn_t *, const int);
429 void		npf_nat_destroy(npf_nat_t *);
430 void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
431 void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
432 void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
433 
434 void		npf_nat_export(nvlist_t *, npf_nat_t *);
435 npf_nat_t *	npf_nat_import(npf_t *, const nvlist_t *, npf_ruleset_t *,
436 		    npf_conn_t *);
437 
438 /* ALG interface. */
439 void		npf_alg_sysinit(void);
440 void		npf_alg_sysfini(void);
441 void		npf_alg_init(npf_t *);
442 void		npf_alg_fini(npf_t *);
443 npf_alg_t *	npf_alg_register(npf_t *, const char *, const npfa_funcs_t *);
444 int		npf_alg_unregister(npf_t *, npf_alg_t *);
445 npf_alg_t *	npf_alg_construct(npf_t *, const char *);
446 bool		npf_alg_match(npf_cache_t *, npf_nat_t *, int);
447 void		npf_alg_exec(npf_cache_t *, npf_nat_t *, bool);
448 npf_conn_t *	npf_alg_conn(npf_cache_t *, int);
449 int		npf_alg_export(npf_t *, nvlist_t *);
450 
451 /* Debugging routines. */
452 const char *	npf_addr_dump(const npf_addr_t *, int);
453 void		npf_state_dump(const npf_state_t *);
454 void		npf_nat_dump(const npf_nat_t *);
455 void		npf_ruleset_dump(npf_t *, const char *);
456 void		npf_state_setsampler(void (*)(npf_state_t *, bool));
457 
458 /* In-kernel routines. */
459 void		npf_setkernctx(npf_t *);
460 npf_t *		npf_getkernctx(void);
461 
462 #ifdef __NetBSD__
463 #define	pserialize_register(x)
464 #define	pserialize_checkpoint(x)
465 #define	pserialize_unregister(x)
466 #endif
467 
468 #endif	/* _NPF_IMPL_H_ */
469