xref: /netbsd-src/sys/net/npf/npf_impl.h (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: npf_impl.h,v 1.70 2017/12/10 01:18:21 rmind Exp $	*/
2 
3 /*-
4  * Copyright (c) 2009-2014 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This material is based upon work partially supported by The
8  * NetBSD Foundation under a contract with Mindaugas Rasiukevicius.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Private NPF structures and interfaces.
34  * For internal use within NPF core only.
35  */
36 
37 #ifndef _NPF_IMPL_H_
38 #define _NPF_IMPL_H_
39 
40 #if !defined(_KERNEL) && !defined(_NPF_STANDALONE)
41 #error "Kernel-level header only"
42 #endif
43 
44 #ifdef _KERNEL_OPT
45 /* For INET/INET6 definitions. */
46 #include "opt_inet.h"
47 #include "opt_inet6.h"
48 #endif
49 
50 #ifdef _KERNEL
51 #include <sys/types.h>
52 #include <sys/queue.h>
53 #include <sys/rbtree.h>
54 
55 #include <net/bpf.h>
56 #include <net/bpfjit.h>
57 #include <net/if.h>
58 #endif
59 
60 #include "npf.h"
61 #include "npfkern.h"
62 
63 #ifdef _NPF_DEBUG
64 #define	NPF_PRINTF(x)	printf x
65 #else
66 #define	NPF_PRINTF(x)
67 #endif
68 
69 /*
70  * STRUCTURE DECLARATIONS.
71  */
72 
73 struct npf_ruleset;
74 struct npf_rule;
75 struct npf_rprocset;
76 struct npf_nat;
77 struct npf_conn;
78 struct npf_config;
79 
80 typedef struct npf_ruleset	npf_ruleset_t;
81 typedef struct npf_rule		npf_rule_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 typedef struct npf_config	npf_config_t;
88 
89 struct npf_conndb;
90 struct npf_table;
91 struct npf_tableset;
92 struct npf_algset;
93 struct npf_ifmap;
94 
95 typedef struct npf_conndb	npf_conndb_t;
96 typedef struct npf_table	npf_table_t;
97 typedef struct npf_tableset	npf_tableset_t;
98 typedef struct npf_algset	npf_algset_t;
99 
100 /*
101  * DEFINITIONS.
102  */
103 
104 typedef void (*npf_workfunc_t)(npf_t *);
105 
106 /*
107  * Some artificial limits.
108  * Note: very unlikely to have many ALGs.
109  */
110 #define	NPF_MAX_RULES		(1024 * 1024)
111 #define	NPF_MAX_TABLES		128
112 #define	NPF_MAX_RPROCS		128
113 #define	NPF_MAX_IFMAP		64
114 #define	NPF_MAX_ALGS		4
115 #define	NPF_MAX_WORKS		4
116 
117 /*
118  * CONNECTION STATE STRUCTURES
119  */
120 
121 #define	NPF_FLOW_FORW		0
122 #define	NPF_FLOW_BACK		1
123 
124 typedef struct {
125 	uint32_t	nst_end;
126 	uint32_t	nst_maxend;
127 	uint32_t	nst_maxwin;
128 	int		nst_wscale;
129 } npf_tcpstate_t;
130 
131 typedef struct {
132 	u_int		nst_state;
133 	npf_tcpstate_t	nst_tcpst[2];
134 } npf_state_t;
135 
136 /*
137  * ALG FUNCTIONS.
138  */
139 
140 typedef struct {
141 	bool		(*match)(npf_cache_t *, npf_nat_t *, int);
142 	bool		(*translate)(npf_cache_t *, npf_nat_t *, bool);
143 	npf_conn_t *	(*inspect)(npf_cache_t *, int);
144 } npfa_funcs_t;
145 
146 /*
147  * NBUF STRUCTURE.
148  */
149 
150 struct nbuf {
151 	struct mbuf *	nb_mbuf0;
152 	struct mbuf *	nb_mbuf;
153 	void *		nb_nptr;
154 	const ifnet_t *	nb_ifp;
155 	unsigned	nb_ifid;
156 	int		nb_flags;
157 	const npf_mbufops_t *nb_mops;
158 };
159 
160 /*
161  * NPF INSTANCE (CONTEXT) STRUCTURE AND AUXILIARY OPERATIONS.
162  */
163 
164 struct npf {
165 	/* Active NPF configuration. */
166 	kmutex_t		config_lock;
167 	pserialize_t		qsbr;
168 	npf_config_t *		config;
169 
170 	/* BPF byte-code context. */
171 	bpf_ctx_t *		bpfctx;
172 	const npf_mbufops_t *	mbufops;
173 
174 	/*
175 	 * Connection tracking state: disabled (off) or enabled (on).
176 	 * Connection tracking database, connection cache and the lock.
177 	 */
178 	volatile int		conn_tracking;
179 	kmutex_t		conn_lock;
180 	npf_conndb_t *		conn_db;
181 	pool_cache_t		conn_cache;
182 
183 	/* ALGs. */
184 	npf_algset_t *		algset;
185 
186 	/* Interface mapping. */
187 	const npf_ifops_t *	ifops;
188 	struct npf_ifmap *	ifmap;
189 	unsigned		ifmap_cnt;
190 
191 	/* Associated worker thread. */
192 	unsigned		worker_id;
193 	void *			worker_entry;
194 
195 	/* List of extensions and its lock. */
196 	LIST_HEAD(, npf_ext)	ext_list;
197 	kmutex_t		ext_lock;
198 
199 	/* Statistics. */
200 	percpu_t *		stats_percpu;
201 };
202 
203 /*
204  * INTERFACES.
205  */
206 
207 /* NPF config, statistics, etc. */
208 void		npf_config_init(npf_t *);
209 void		npf_config_fini(npf_t *);
210 
211 void		npf_config_enter(npf_t *);
212 void		npf_config_exit(npf_t *);
213 void		npf_config_sync(npf_t *);
214 bool		npf_config_locked_p(npf_t *);
215 int		npf_config_read_enter(void);
216 void		npf_config_read_exit(int s);
217 
218 void		npf_config_load(npf_t *, npf_ruleset_t *, npf_tableset_t *,
219 		    npf_ruleset_t *, npf_rprocset_t *, npf_conndb_t *, bool);
220 npf_ruleset_t *	npf_config_ruleset(npf_t *npf);
221 npf_ruleset_t *	npf_config_natset(npf_t *npf);
222 npf_tableset_t *npf_config_tableset(npf_t *npf);
223 npf_rprocset_t *npf_config_rprocs(npf_t *);
224 bool		npf_default_pass(npf_t *);
225 
226 int		npf_worker_sysinit(unsigned);
227 void		npf_worker_sysfini(void);
228 void		npf_worker_signal(npf_t *);
229 void		npf_worker_register(npf_t *, npf_workfunc_t);
230 void		npf_worker_unregister(npf_t *, npf_workfunc_t);
231 
232 int		npfctl_switch(void *);
233 int		npfctl_reload(u_long, void *);
234 int		npfctl_save(npf_t *, u_long, void *);
235 int		npfctl_load(npf_t *, u_long, void *);
236 int		npfctl_rule(npf_t *, u_long, void *);
237 int		npfctl_conn_lookup(npf_t *, u_long, void *);
238 int		npfctl_table(npf_t *, void *);
239 
240 void		npf_stats_inc(npf_t *, npf_stats_t);
241 void		npf_stats_dec(npf_t *, npf_stats_t);
242 
243 void		npf_ifmap_init(npf_t *, const npf_ifops_t *);
244 void		npf_ifmap_fini(npf_t *);
245 u_int		npf_ifmap_register(npf_t *, const char *);
246 void		npf_ifmap_flush(npf_t *);
247 u_int		npf_ifmap_getid(npf_t *, const ifnet_t *);
248 const char *	npf_ifmap_getname(npf_t *, const u_int);
249 void		npf_ifmap_copyname(npf_t *, u_int, char *, size_t);
250 
251 void		npf_ifaddr_sync(npf_t *, ifnet_t *);
252 void		npf_ifaddr_flush(npf_t *, ifnet_t *);
253 void		npf_ifaddr_syncall(npf_t *);
254 
255 /* Packet filter hooks. */
256 int		npf_pfil_register(bool);
257 void		npf_pfil_unregister(bool);
258 bool		npf_pfil_registered_p(void);
259 
260 /* Protocol helpers. */
261 int		npf_cache_all(npf_cache_t *);
262 void		npf_recache(npf_cache_t *);
263 
264 bool		npf_rwrip(const npf_cache_t *, u_int, const npf_addr_t *);
265 bool		npf_rwrport(const npf_cache_t *, u_int, const in_port_t);
266 bool		npf_rwrcksum(const npf_cache_t *, u_int,
267 		    const npf_addr_t *, const in_port_t);
268 int		npf_napt_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
269 		    const in_addr_t);
270 int		npf_npt66_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
271 		    npf_netmask_t, uint16_t);
272 
273 uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
274 uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
275 uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
276 		    const npf_addr_t *);
277 uint32_t	npf_addr_mix(const int, const npf_addr_t *, const npf_addr_t *);
278 int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
279 		    const npf_addr_t *, const npf_netmask_t, const int);
280 void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
281 		    const int, npf_addr_t *);
282 
283 int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
284 		    uint32_t *);
285 bool		npf_fetch_tcpopts(npf_cache_t *, uint16_t *, int *);
286 bool		npf_return_block(npf_cache_t *, const int);
287 
288 /* BPF interface. */
289 void		npf_bpf_sysinit(void);
290 void		npf_bpf_sysfini(void);
291 void		npf_bpf_prepare(npf_cache_t *, bpf_args_t *, uint32_t *);
292 int		npf_bpf_filter(bpf_args_t *, const void *, bpfjit_func_t);
293 void *		npf_bpf_compile(void *, size_t);
294 bool		npf_bpf_validate(const void *, size_t);
295 
296 /* Tableset interface. */
297 void		npf_tableset_sysinit(void);
298 void		npf_tableset_sysfini(void);
299 
300 npf_tableset_t *npf_tableset_create(u_int);
301 void		npf_tableset_destroy(npf_tableset_t *);
302 int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
303 npf_table_t *	npf_tableset_getbyname(npf_tableset_t *, const char *);
304 npf_table_t *	npf_tableset_getbyid(npf_tableset_t *, u_int);
305 npf_table_t *	npf_tableset_swap(npf_tableset_t *, npf_table_t *);
306 void		npf_tableset_reload(npf_t *, npf_tableset_t *, npf_tableset_t *);
307 int		npf_tableset_export(npf_t *, const npf_tableset_t *, prop_array_t);
308 
309 npf_table_t *	npf_table_create(const char *, u_int, int, void *, size_t);
310 void		npf_table_destroy(npf_table_t *);
311 
312 u_int		npf_table_getid(npf_table_t *);
313 int		npf_table_check(npf_tableset_t *, const char *, u_int, int);
314 int		npf_table_insert(npf_table_t *, const int,
315 		    const npf_addr_t *, const npf_netmask_t);
316 int		npf_table_remove(npf_table_t *, const int,
317 		    const npf_addr_t *, const npf_netmask_t);
318 int		npf_table_lookup(npf_table_t *, const int, const npf_addr_t *);
319 int		npf_table_list(npf_table_t *, void *, size_t);
320 int		npf_table_flush(npf_table_t *);
321 
322 /* Ruleset interface. */
323 npf_ruleset_t *	npf_ruleset_create(size_t);
324 void		npf_ruleset_destroy(npf_ruleset_t *);
325 void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
326 void		npf_ruleset_reload(npf_t *, npf_ruleset_t *,
327 		    npf_ruleset_t *, bool);
328 npf_rule_t *	npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
329 npf_natpolicy_t *npf_ruleset_findnat(npf_ruleset_t *, uint64_t);
330 void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
331 int		npf_ruleset_export(npf_t *, const npf_ruleset_t *, prop_array_t);
332 
333 npf_rule_t *	npf_ruleset_lookup(npf_ruleset_t *, const char *);
334 int		npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
335 int		npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
336 int		npf_ruleset_remkey(npf_ruleset_t *, const char *,
337 		    const void *, size_t);
338 prop_dictionary_t npf_ruleset_list(npf_t *, npf_ruleset_t *, const char *);
339 int		npf_ruleset_flush(npf_ruleset_t *, const char *);
340 void		npf_ruleset_gc(npf_ruleset_t *);
341 
342 npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, const npf_ruleset_t *,
343 		    const int, const int);
344 int		npf_rule_conclude(const npf_rule_t *, npf_match_info_t *);
345 
346 /* Rule interface. */
347 npf_rule_t *	npf_rule_alloc(npf_t *, prop_dictionary_t);
348 void		npf_rule_setcode(npf_rule_t *, int, void *, size_t);
349 void		npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
350 void		npf_rule_free(npf_rule_t *);
351 uint64_t	npf_rule_getid(const npf_rule_t *);
352 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
353 void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
354 npf_rproc_t *	npf_rule_getrproc(const npf_rule_t *);
355 
356 void		npf_ext_init(npf_t *);
357 void		npf_ext_fini(npf_t *);
358 int		npf_ext_construct(npf_t *, const char *,
359 		    npf_rproc_t *, prop_dictionary_t);
360 
361 npf_rprocset_t *npf_rprocset_create(void);
362 void		npf_rprocset_destroy(npf_rprocset_t *);
363 npf_rproc_t *	npf_rprocset_lookup(npf_rprocset_t *, const char *);
364 void		npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
365 int		npf_rprocset_export(const npf_rprocset_t *, prop_array_t);
366 
367 npf_rproc_t *	npf_rproc_create(prop_dictionary_t);
368 void		npf_rproc_acquire(npf_rproc_t *);
369 void		npf_rproc_release(npf_rproc_t *);
370 const char *	npf_rproc_getname(const npf_rproc_t *);
371 bool		npf_rproc_run(npf_cache_t *, npf_rproc_t *,
372 		    const npf_match_info_t *, int *);
373 
374 /* State handling. */
375 bool		npf_state_init(npf_cache_t *, npf_state_t *);
376 bool		npf_state_inspect(npf_cache_t *, npf_state_t *, const bool);
377 int		npf_state_etime(const npf_state_t *, const int);
378 void		npf_state_destroy(npf_state_t *);
379 
380 bool		npf_state_tcp(npf_cache_t *, npf_state_t *, int);
381 int		npf_state_tcp_timeout(const npf_state_t *);
382 
383 /* NAT. */
384 void		npf_nat_sysinit(void);
385 void		npf_nat_sysfini(void);
386 npf_natpolicy_t *npf_nat_newpolicy(npf_t *, prop_dictionary_t, npf_ruleset_t *);
387 int		npf_nat_policyexport(const npf_natpolicy_t *, prop_dictionary_t);
388 void		npf_nat_freepolicy(npf_natpolicy_t *);
389 bool		npf_nat_cmppolicy(npf_natpolicy_t *, npf_natpolicy_t *);
390 bool		npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
391 void		npf_nat_setid(npf_natpolicy_t *, uint64_t);
392 uint64_t	npf_nat_getid(const npf_natpolicy_t *);
393 void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
394 
395 int		npf_do_nat(npf_cache_t *, npf_conn_t *, const int);
396 void		npf_nat_destroy(npf_nat_t *);
397 void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
398 void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
399 void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
400 
401 void		npf_nat_export(prop_dictionary_t, npf_nat_t *);
402 npf_nat_t *	npf_nat_import(npf_t *, prop_dictionary_t, npf_ruleset_t *,
403 		    npf_conn_t *);
404 
405 /* ALG interface. */
406 void		npf_alg_init(npf_t *);
407 void		npf_alg_fini(npf_t *);
408 npf_alg_t *	npf_alg_register(npf_t *, const char *, const npfa_funcs_t *);
409 int		npf_alg_unregister(npf_t *, npf_alg_t *);
410 npf_alg_t *	npf_alg_construct(npf_t *, const char *);
411 bool		npf_alg_match(npf_cache_t *, npf_nat_t *, int);
412 void		npf_alg_exec(npf_cache_t *, npf_nat_t *, bool);
413 npf_conn_t *	npf_alg_conn(npf_cache_t *, int);
414 prop_array_t	npf_alg_export(npf_t *);
415 
416 /* Debugging routines. */
417 const char *	npf_addr_dump(const npf_addr_t *, int);
418 void		npf_state_dump(const npf_state_t *);
419 void		npf_nat_dump(const npf_nat_t *);
420 void		npf_ruleset_dump(npf_t *, const char *);
421 void		npf_state_setsampler(void (*)(npf_state_t *, bool));
422 
423 /* In-kernel routines. */
424 void		npf_setkernctx(npf_t *);
425 npf_t *		npf_getkernctx(void);
426 
427 #ifdef __NetBSD__
428 #define	pserialize_register(x)
429 #define	pserialize_checkpoint(x)
430 #endif
431 
432 #endif	/* _NPF_IMPL_H_ */
433