xref: /netbsd-src/sys/net/npf/npf_impl.h (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: npf_impl.h,v 1.45 2013/12/06 01:33:37 rmind Exp $	*/
2 
3 /*-
4  * Copyright (c) 2009-2013 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 bool (*npf_alg_func_t)(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
100 typedef npf_session_t *(*npf_alg_sfunc_t)(npf_cache_t *, nbuf_t *, int);
101 typedef void (*npf_workfunc_t)(void);
102 
103 /*
104  * Some artificial limits.
105  * Note: very unlikely to have many ALGs.
106  */
107 #define	NPF_MAX_RULES		(1024 * 1024)
108 #define	NPF_MAX_ALGS		4
109 #define	NPF_MAX_TABLES		128
110 #define	NPF_MAX_RPROCS		128
111 #define	NPF_MAX_IFMAP		64
112 
113 /*
114  * SESSION STATE STRUCTURES
115  */
116 
117 #define	NPF_FLOW_FORW		0
118 #define	NPF_FLOW_BACK		1
119 
120 typedef struct {
121 	uint32_t	nst_end;
122 	uint32_t	nst_maxend;
123 	uint32_t	nst_maxwin;
124 	int		nst_wscale;
125 } npf_tcpstate_t;
126 
127 typedef struct {
128 	kmutex_t	nst_lock;
129 	u_int		nst_state;
130 	npf_tcpstate_t	nst_tcpst[2];
131 } npf_state_t;
132 
133 /*
134  * INTERFACES.
135  */
136 
137 /* NPF config, statistics, etc. */
138 void		npf_config_init(void);
139 void		npf_config_fini(void);
140 
141 void		npf_config_enter(void);
142 void		npf_config_exit(void);
143 void		npf_config_sync(void);
144 bool		npf_config_locked_p(void);
145 int		npf_config_read_enter(void);
146 void		npf_config_read_exit(int);
147 
148 void		npf_config_reload(prop_dictionary_t, npf_ruleset_t *,
149 		    npf_tableset_t *, npf_ruleset_t *, npf_rprocset_t *, bool);
150 npf_ruleset_t *	npf_config_ruleset(void);
151 npf_ruleset_t *	npf_config_natset(void);
152 npf_tableset_t *npf_config_tableset(void);
153 prop_dictionary_t npf_config_dict(void);
154 bool		npf_default_pass(void);
155 
156 int		npf_worker_sysinit(void);
157 void		npf_worker_sysfini(void);
158 void		npf_worker_signal(void);
159 void		npf_worker_register(npf_workfunc_t);
160 void		npf_worker_unregister(npf_workfunc_t);
161 
162 void		npflogattach(int);
163 void		npflogdetach(void);
164 int		npfctl_switch(void *);
165 int		npfctl_reload(u_long, void *);
166 int		npfctl_getconf(u_long, void *);
167 int		npfctl_sessions_save(u_long, void *);
168 int		npfctl_sessions_load(u_long, void *);
169 int		npfctl_rule(u_long, void *);
170 int		npfctl_table(void *);
171 
172 void		npf_stats_inc(npf_stats_t);
173 void		npf_stats_dec(npf_stats_t);
174 
175 u_int		npf_ifmap_register(const char *);
176 void		npf_ifmap_flush(void);
177 void		npf_ifmap_attach(ifnet_t *);
178 void		npf_ifmap_detach(ifnet_t *);
179 u_int		npf_ifmap_id(const ifnet_t *);
180 
181 /* Packet filter hooks. */
182 int		npf_pfil_register(bool);
183 void		npf_pfil_unregister(bool);
184 bool		npf_pfil_registered_p(void);
185 int		npf_packet_handler(void *, struct mbuf **, ifnet_t *, int);
186 
187 /* Protocol helpers. */
188 int		npf_cache_all(npf_cache_t *, nbuf_t *);
189 void		npf_recache(npf_cache_t *, nbuf_t *);
190 
191 bool		npf_rwrip(const npf_cache_t *, u_int, const npf_addr_t *);
192 bool		npf_rwrport(const npf_cache_t *, u_int, const in_port_t);
193 bool		npf_rwrcksum(const npf_cache_t *, u_int,
194 		    const npf_addr_t *, const in_port_t);
195 
196 uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
197 uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
198 uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
199 		    const npf_addr_t *);
200 uint32_t	npf_addr_mix(const int, const npf_addr_t *, const npf_addr_t *);
201 int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
202 		    const npf_addr_t *, const npf_netmask_t, const int);
203 void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
204 		    const int, npf_addr_t *);
205 
206 int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
207 		    uint32_t *);
208 bool		npf_fetch_tcpopts(npf_cache_t *, nbuf_t *, uint16_t *, int *);
209 bool		npf_return_block(npf_cache_t *, nbuf_t *, const int);
210 
211 /* BPF interface. */
212 void		npf_bpf_sysinit(void);
213 void		npf_bpf_sysfini(void);
214 int		npf_bpf_filter(bpf_args_t *, const void *, bpfjit_func_t);
215 void *		npf_bpf_compile(void *, size_t);
216 bool		npf_bpf_validate(const void *, size_t);
217 
218 /* Tableset interface. */
219 void		npf_tableset_sysinit(void);
220 void		npf_tableset_sysfini(void);
221 
222 extern const pt_tree_ops_t npf_table_ptree_ops;
223 
224 npf_tableset_t *npf_tableset_create(u_int);
225 void		npf_tableset_destroy(npf_tableset_t *);
226 int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
227 npf_table_t *	npf_tableset_getbyname(npf_tableset_t *, const char *);
228 npf_table_t *	npf_tableset_getbyid(npf_tableset_t *, u_int);
229 void		npf_tableset_reload(npf_tableset_t *, npf_tableset_t *);
230 void		npf_tableset_syncdict(const npf_tableset_t *, prop_dictionary_t);
231 
232 npf_table_t *	npf_table_create(const char *, u_int, int, size_t);
233 void		npf_table_destroy(npf_table_t *);
234 
235 int		npf_table_check(npf_tableset_t *, const char *, u_int, int);
236 int		npf_table_insert(npf_table_t *, const int,
237 		    const npf_addr_t *, const npf_netmask_t);
238 int		npf_table_remove(npf_table_t *, const int,
239 		    const npf_addr_t *, const npf_netmask_t);
240 int		npf_table_lookup(npf_table_t *, const int, const npf_addr_t *);
241 int		npf_table_list(npf_table_t *, void *, size_t);
242 int		npf_table_flush(npf_table_t *);
243 
244 /* Ruleset interface. */
245 npf_ruleset_t *	npf_ruleset_create(size_t);
246 void		npf_ruleset_destroy(npf_ruleset_t *);
247 void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
248 void		npf_ruleset_reload(npf_ruleset_t *, npf_ruleset_t *);
249 void		npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *);
250 npf_rule_t *	npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
251 npf_rule_t *	npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
252 void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
253 
254 int		npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
255 int		npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
256 int		npf_ruleset_remkey(npf_ruleset_t *, const char *,
257 		    const void *, size_t);
258 prop_dictionary_t npf_ruleset_list(npf_ruleset_t *, const char *);
259 int		npf_ruleset_flush(npf_ruleset_t *, const char *);
260 void		npf_ruleset_gc(npf_ruleset_t *);
261 
262 npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, nbuf_t *,
263 		    const npf_ruleset_t *, const int, const int);
264 int		npf_rule_conclude(const npf_rule_t *, int *);
265 
266 /* Rule interface. */
267 npf_rule_t *	npf_rule_alloc(prop_dictionary_t);
268 void		npf_rule_setcode(npf_rule_t *, int, void *, size_t);
269 void		npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
270 void		npf_rule_free(npf_rule_t *);
271 uint64_t	npf_rule_getid(const npf_rule_t *);
272 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
273 void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
274 npf_rproc_t *	npf_rule_getrproc(const npf_rule_t *);
275 
276 void		npf_ext_sysinit(void);
277 void		npf_ext_sysfini(void);
278 int		npf_ext_construct(const char *,
279 		    npf_rproc_t *, prop_dictionary_t);
280 
281 npf_rprocset_t *npf_rprocset_create(void);
282 void		npf_rprocset_destroy(npf_rprocset_t *);
283 npf_rproc_t *	npf_rprocset_lookup(npf_rprocset_t *, const char *);
284 void		npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
285 
286 npf_rproc_t *	npf_rproc_create(prop_dictionary_t);
287 void		npf_rproc_acquire(npf_rproc_t *);
288 void		npf_rproc_release(npf_rproc_t *);
289 void		npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int *);
290 
291 /* Session handling interface. */
292 void		npf_session_sysinit(void);
293 void		npf_session_sysfini(void);
294 void		npf_session_tracking(bool);
295 
296 npf_sehash_t *	sess_htable_create(void);
297 void		sess_htable_destroy(npf_sehash_t *);
298 
299 npf_session_t *	npf_session_lookup(const npf_cache_t *, const nbuf_t *,
300 		    const int, bool *);
301 npf_session_t *	npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
302 npf_session_t *	npf_session_establish(npf_cache_t *, nbuf_t *, const int);
303 void		npf_session_release(npf_session_t *);
304 void		npf_session_expire(npf_session_t *);
305 bool		npf_session_pass(const npf_session_t *, npf_rproc_t **);
306 void		npf_session_setpass(npf_session_t *, npf_rproc_t *);
307 int		npf_session_setnat(npf_session_t *, npf_nat_t *, u_int);
308 npf_nat_t *	npf_session_retnat(npf_session_t *, const int, bool *);
309 
310 void		npf_session_load(npf_sehash_t *);
311 int		npf_session_save(prop_array_t, prop_array_t);
312 int		npf_session_restore(npf_sehash_t *, prop_dictionary_t);
313 
314 /* State handling. */
315 bool		npf_state_init(npf_cache_t *, nbuf_t *, npf_state_t *);
316 bool		npf_state_inspect(npf_cache_t *, nbuf_t *, npf_state_t *,
317 		    const bool);
318 int		npf_state_etime(const npf_state_t *, const int);
319 void		npf_state_destroy(npf_state_t *);
320 
321 bool		npf_state_tcp(npf_cache_t *, nbuf_t *, npf_state_t *, int);
322 int		npf_state_tcp_timeout(const npf_state_t *);
323 
324 /* NAT. */
325 void		npf_nat_sysinit(void);
326 void		npf_nat_sysfini(void);
327 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
328 void		npf_nat_freepolicy(npf_natpolicy_t *);
329 bool		npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
330 bool		npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
331 void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
332 
333 int		npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, const int);
334 int		npf_nat_translate(npf_cache_t *, nbuf_t *, npf_nat_t *, bool);
335 void		npf_nat_destroy(npf_nat_t *);
336 void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
337 void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
338 void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
339 
340 int		npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
341 npf_nat_t *	npf_nat_restore(prop_dictionary_t, npf_session_t *);
342 
343 /* ALG interface. */
344 void		npf_alg_sysinit(void);
345 void		npf_alg_sysfini(void);
346 npf_alg_t *	npf_alg_register(const char *, npf_alg_func_t, npf_alg_func_t,
347 		    npf_alg_sfunc_t);
348 int		npf_alg_unregister(npf_alg_t *);
349 npf_alg_t *	npf_alg_construct(const char *);
350 bool		npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
351 void		npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, bool);
352 npf_session_t *	npf_alg_session(npf_cache_t *, nbuf_t *, int);
353 
354 /* Debugging routines. */
355 void		npf_addr_dump(const npf_addr_t *);
356 void		npf_sessions_dump(void);
357 void		npf_state_dump(const npf_state_t *);
358 void		npf_nat_dump(const npf_nat_t *);
359 void		npf_state_setsampler(void (*)(npf_state_t *, bool));
360 
361 #endif	/* _NPF_IMPL_H_ */
362