xref: /netbsd-src/sys/net/npf/npf_impl.h (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: npf_impl.h,v 1.53 2014/06/25 00:20:06 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)
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 #include <sys/types.h>
51 #include <sys/queue.h>
52 #include <sys/hash.h>
53 #include <sys/rbtree.h>
54 #include <sys/ptree.h>
55 #include <sys/rwlock.h>
56 
57 #include <net/bpf.h>
58 #include <net/bpfjit.h>
59 #include <net/if.h>
60 
61 #include "npf.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_session;
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_session	npf_session_t;
86 
87 struct npf_sehash;
88 struct npf_table;
89 struct npf_tableset;
90 
91 typedef struct npf_sehash	npf_sehash_t;
92 typedef struct npf_table	npf_table_t;
93 typedef struct npf_tableset	npf_tableset_t;
94 
95 /*
96  * DEFINITIONS.
97  */
98 
99 typedef void (*npf_workfunc_t)(void);
100 
101 /*
102  * Some artificial limits.
103  * Note: very unlikely to have many ALGs.
104  */
105 #define	NPF_MAX_RULES		(1024 * 1024)
106 #define	NPF_MAX_ALGS		4
107 #define	NPF_MAX_TABLES		128
108 #define	NPF_MAX_RPROCS		128
109 #define	NPF_MAX_IFMAP		64
110 
111 /*
112  * SESSION STATE STRUCTURES
113  */
114 
115 #define	NPF_FLOW_FORW		0
116 #define	NPF_FLOW_BACK		1
117 
118 typedef struct {
119 	uint32_t	nst_end;
120 	uint32_t	nst_maxend;
121 	uint32_t	nst_maxwin;
122 	int		nst_wscale;
123 } npf_tcpstate_t;
124 
125 typedef struct {
126 	kmutex_t	nst_lock;
127 	u_int		nst_state;
128 	npf_tcpstate_t	nst_tcpst[2];
129 } npf_state_t;
130 
131 /*
132  * ALG FUNCTIONS.
133  */
134 
135 typedef struct {
136 	bool		(*match)(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
137 	bool		(*translate)(npf_cache_t *, nbuf_t *, npf_nat_t *, bool);
138 	npf_session_t * (*inspect)(npf_cache_t *, nbuf_t *, int);
139 } npfa_funcs_t;
140 
141 /*
142  * INTERFACES.
143  */
144 
145 /* NPF config, statistics, etc. */
146 void		npf_config_init(void);
147 void		npf_config_fini(void);
148 
149 void		npf_config_enter(void);
150 void		npf_config_exit(void);
151 void		npf_config_sync(void);
152 bool		npf_config_locked_p(void);
153 int		npf_config_read_enter(void);
154 void		npf_config_read_exit(int);
155 
156 void		npf_config_reload(prop_dictionary_t, npf_ruleset_t *,
157 		    npf_tableset_t *, npf_ruleset_t *, npf_rprocset_t *, bool);
158 npf_ruleset_t *	npf_config_ruleset(void);
159 npf_ruleset_t *	npf_config_natset(void);
160 npf_tableset_t *npf_config_tableset(void);
161 prop_dictionary_t npf_config_dict(void);
162 bool		npf_default_pass(void);
163 
164 int		npf_worker_sysinit(void);
165 void		npf_worker_sysfini(void);
166 void		npf_worker_signal(void);
167 void		npf_worker_register(npf_workfunc_t);
168 void		npf_worker_unregister(npf_workfunc_t);
169 
170 void		npflogattach(int);
171 void		npflogdetach(void);
172 int		npfctl_switch(void *);
173 int		npfctl_reload(u_long, void *);
174 int		npfctl_getconf(u_long, void *);
175 int		npfctl_sessions_save(u_long, void *);
176 int		npfctl_sessions_load(u_long, void *);
177 int		npfctl_rule(u_long, void *);
178 int		npfctl_table(void *);
179 
180 void		npf_stats_inc(npf_stats_t);
181 void		npf_stats_dec(npf_stats_t);
182 
183 u_int		npf_ifmap_register(const char *);
184 void		npf_ifmap_flush(void);
185 void		npf_ifmap_attach(ifnet_t *);
186 void		npf_ifmap_detach(ifnet_t *);
187 u_int		npf_ifmap_id(const ifnet_t *);
188 
189 /* Packet filter hooks. */
190 int		npf_pfil_register(bool);
191 void		npf_pfil_unregister(bool);
192 bool		npf_pfil_registered_p(void);
193 int		npf_packet_handler(void *, struct mbuf **, ifnet_t *, int);
194 
195 /* Protocol helpers. */
196 int		npf_cache_all(npf_cache_t *, nbuf_t *);
197 void		npf_recache(npf_cache_t *, nbuf_t *);
198 
199 bool		npf_rwrip(const npf_cache_t *, u_int, const npf_addr_t *);
200 bool		npf_rwrport(const npf_cache_t *, u_int, const in_port_t);
201 bool		npf_rwrcksum(const npf_cache_t *, u_int,
202 		    const npf_addr_t *, const in_port_t);
203 int		npf_napt_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
204 		    const in_addr_t);
205 int		npf_npt66_rwr(const npf_cache_t *, u_int, const npf_addr_t *,
206 		    npf_netmask_t, uint16_t);
207 
208 uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
209 uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
210 uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
211 		    const npf_addr_t *);
212 uint32_t	npf_addr_mix(const int, const npf_addr_t *, const npf_addr_t *);
213 int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
214 		    const npf_addr_t *, const npf_netmask_t, const int);
215 void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
216 		    const int, npf_addr_t *);
217 
218 int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
219 		    uint32_t *);
220 bool		npf_fetch_tcpopts(npf_cache_t *, nbuf_t *, uint16_t *, int *);
221 bool		npf_return_block(npf_cache_t *, nbuf_t *, const int);
222 
223 /* BPF interface. */
224 void		npf_bpf_sysinit(void);
225 void		npf_bpf_sysfini(void);
226 void		npf_bpf_prepare(npf_cache_t *, nbuf_t *, bpf_args_t *, uint32_t *);
227 int		npf_bpf_filter(bpf_args_t *, const void *, bpfjit_func_t);
228 void *		npf_bpf_compile(void *, size_t);
229 bool		npf_bpf_validate(const void *, size_t);
230 
231 /* Tableset interface. */
232 void		npf_tableset_sysinit(void);
233 void		npf_tableset_sysfini(void);
234 
235 extern const pt_tree_ops_t npf_table_ptree_ops;
236 
237 npf_tableset_t *npf_tableset_create(u_int);
238 void		npf_tableset_destroy(npf_tableset_t *);
239 int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
240 npf_table_t *	npf_tableset_getbyname(npf_tableset_t *, const char *);
241 npf_table_t *	npf_tableset_getbyid(npf_tableset_t *, u_int);
242 void		npf_tableset_reload(npf_tableset_t *, npf_tableset_t *);
243 void		npf_tableset_syncdict(const npf_tableset_t *, prop_dictionary_t);
244 
245 npf_table_t *	npf_table_create(const char *, u_int, int, void *, size_t);
246 void		npf_table_destroy(npf_table_t *);
247 
248 int		npf_table_check(npf_tableset_t *, const char *, u_int, int);
249 int		npf_table_insert(npf_table_t *, const int,
250 		    const npf_addr_t *, const npf_netmask_t);
251 int		npf_table_remove(npf_table_t *, const int,
252 		    const npf_addr_t *, const npf_netmask_t);
253 int		npf_table_lookup(npf_table_t *, const int, const npf_addr_t *);
254 int		npf_table_list(npf_table_t *, void *, size_t);
255 int		npf_table_flush(npf_table_t *);
256 
257 /* Ruleset interface. */
258 npf_ruleset_t *	npf_ruleset_create(size_t);
259 void		npf_ruleset_destroy(npf_ruleset_t *);
260 void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
261 void		npf_ruleset_reload(npf_ruleset_t *, npf_ruleset_t *);
262 npf_rule_t *	npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
263 npf_rule_t *	npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
264 void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
265 
266 int		npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
267 int		npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
268 int		npf_ruleset_remkey(npf_ruleset_t *, const char *,
269 		    const void *, size_t);
270 prop_dictionary_t npf_ruleset_list(npf_ruleset_t *, const char *);
271 int		npf_ruleset_flush(npf_ruleset_t *, const char *);
272 void		npf_ruleset_gc(npf_ruleset_t *);
273 
274 npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, nbuf_t *,
275 		    const npf_ruleset_t *, const int, const int);
276 int		npf_rule_conclude(const npf_rule_t *, int *);
277 
278 /* Rule interface. */
279 npf_rule_t *	npf_rule_alloc(prop_dictionary_t);
280 void		npf_rule_setcode(npf_rule_t *, int, void *, size_t);
281 void		npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
282 void		npf_rule_free(npf_rule_t *);
283 uint64_t	npf_rule_getid(const npf_rule_t *);
284 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
285 void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
286 npf_rproc_t *	npf_rule_getrproc(const npf_rule_t *);
287 
288 void		npf_ext_sysinit(void);
289 void		npf_ext_sysfini(void);
290 int		npf_ext_construct(const char *,
291 		    npf_rproc_t *, prop_dictionary_t);
292 
293 npf_rprocset_t *npf_rprocset_create(void);
294 void		npf_rprocset_destroy(npf_rprocset_t *);
295 npf_rproc_t *	npf_rprocset_lookup(npf_rprocset_t *, const char *);
296 void		npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
297 
298 npf_rproc_t *	npf_rproc_create(prop_dictionary_t);
299 void		npf_rproc_acquire(npf_rproc_t *);
300 void		npf_rproc_release(npf_rproc_t *);
301 bool		npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int *);
302 
303 /* Session handling interface. */
304 void		npf_session_sysinit(void);
305 void		npf_session_sysfini(void);
306 void		npf_session_tracking(bool);
307 
308 npf_sehash_t *	sess_htable_create(void);
309 void		sess_htable_destroy(npf_sehash_t *);
310 
311 npf_session_t *	npf_session_lookup(const npf_cache_t *, const nbuf_t *,
312 		    const int, bool *);
313 npf_session_t *	npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
314 npf_session_t *	npf_session_establish(npf_cache_t *, nbuf_t *, int, bool);
315 void		npf_session_release(npf_session_t *);
316 void		npf_session_expire(npf_session_t *);
317 bool		npf_session_pass(const npf_session_t *, npf_rproc_t **);
318 void		npf_session_setpass(npf_session_t *, npf_rproc_t *);
319 int		npf_session_setnat(npf_session_t *, npf_nat_t *, u_int);
320 npf_nat_t *	npf_session_retnat(npf_session_t *, const int, bool *);
321 
322 void		npf_session_load(npf_sehash_t *);
323 int		npf_session_save(prop_array_t, prop_array_t);
324 int		npf_session_restore(npf_sehash_t *, prop_dictionary_t);
325 
326 /* State handling. */
327 bool		npf_state_init(npf_cache_t *, nbuf_t *, npf_state_t *);
328 bool		npf_state_inspect(npf_cache_t *, nbuf_t *, npf_state_t *,
329 		    const bool);
330 int		npf_state_etime(const npf_state_t *, const int);
331 void		npf_state_destroy(npf_state_t *);
332 
333 bool		npf_state_tcp(npf_cache_t *, nbuf_t *, npf_state_t *, int);
334 int		npf_state_tcp_timeout(const npf_state_t *);
335 
336 /* NAT. */
337 void		npf_nat_sysinit(void);
338 void		npf_nat_sysfini(void);
339 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
340 void		npf_nat_freepolicy(npf_natpolicy_t *);
341 bool		npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
342 bool		npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
343 void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
344 
345 int		npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, const int);
346 void		npf_nat_destroy(npf_nat_t *);
347 void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
348 void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
349 void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
350 
351 int		npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
352 npf_nat_t *	npf_nat_restore(prop_dictionary_t, npf_session_t *);
353 
354 /* ALG interface. */
355 void		npf_alg_sysinit(void);
356 void		npf_alg_sysfini(void);
357 npf_alg_t *	npf_alg_register(const char *, const npfa_funcs_t *);
358 int		npf_alg_unregister(npf_alg_t *);
359 npf_alg_t *	npf_alg_construct(const char *);
360 bool		npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
361 void		npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, bool);
362 npf_session_t *	npf_alg_session(npf_cache_t *, nbuf_t *, int);
363 
364 /* Debugging routines. */
365 void		npf_addr_dump(const npf_addr_t *);
366 void		npf_sessions_dump(void);
367 void		npf_state_dump(const npf_state_t *);
368 void		npf_nat_dump(const npf_nat_t *);
369 void		npf_state_setsampler(void (*)(npf_state_t *, bool));
370 
371 #endif	/* _NPF_IMPL_H_ */
372