xref: /netbsd-src/sys/net/npf/npf_impl.h (revision 7788a0781fe6ff2cce37368b4578a7ade0850cb1)
1 /*	$NetBSD: npf_impl.h,v 1.31 2013/06/02 02:20:04 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 #include <net/if.h>
57 
58 #include "npf.h"
59 #include "npf_ncode.h"
60 
61 #ifdef _NPF_DEBUG
62 #define	NPF_PRINTF(x)	printf x
63 #else
64 #define	NPF_PRINTF(x)
65 #endif
66 
67 /*
68  * STRUCTURE DECLARATIONS.
69  */
70 
71 struct npf_ruleset;
72 struct npf_rule;
73 struct npf_rprocset;
74 struct npf_nat;
75 struct npf_session;
76 
77 typedef struct npf_ruleset	npf_ruleset_t;
78 typedef struct npf_rule		npf_rule_t;
79 typedef struct npf_nat		npf_nat_t;
80 typedef struct npf_rprocset	npf_rprocset_t;
81 typedef struct npf_alg		npf_alg_t;
82 typedef struct npf_natpolicy	npf_natpolicy_t;
83 typedef struct npf_session	npf_session_t;
84 
85 struct npf_sehash;
86 struct npf_table;
87 
88 typedef struct npf_sehash	npf_sehash_t;
89 typedef struct npf_table	npf_table_t;
90 
91 typedef npf_table_t *		npf_tableset_t;
92 
93 /*
94  * DEFINITIONS.
95  */
96 
97 typedef bool (*npf_alg_func_t)(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
98 typedef npf_session_t *(*npf_alg_sfunc_t)(npf_cache_t *, nbuf_t *, int);
99 typedef void (*npf_workfunc_t)(void);
100 
101 #define	NPF_NCODE_LIMIT		1024
102 #define	NPF_TABLE_SLOTS		32
103 
104 /*
105  * SESSION STATE STRUCTURES
106  */
107 
108 #define	NPF_FLOW_FORW		0
109 #define	NPF_FLOW_BACK		1
110 
111 typedef struct {
112 	uint32_t	nst_end;
113 	uint32_t	nst_maxend;
114 	uint32_t	nst_maxwin;
115 	int		nst_wscale;
116 } npf_tcpstate_t;
117 
118 typedef struct {
119 	kmutex_t	nst_lock;
120 	int		nst_state;
121 	npf_tcpstate_t	nst_tcpst[2];
122 } npf_state_t;
123 
124 /*
125  * INTERFACES.
126  */
127 
128 /* NPF config, statistics, etc. */
129 void		npf_config_init(void);
130 void		npf_config_fini(void);
131 
132 void		npf_config_enter(void);
133 void		npf_config_exit(void);
134 void		npf_config_sync(void);
135 bool		npf_config_locked_p(void);
136 int		npf_config_read_enter(void);
137 void		npf_config_read_exit(int);
138 
139 void		npf_config_reload(prop_dictionary_t, npf_ruleset_t *,
140 		    npf_tableset_t *, npf_ruleset_t *, npf_rprocset_t *, bool);
141 npf_ruleset_t *	npf_config_ruleset(void);
142 npf_ruleset_t *	npf_config_natset(void);
143 npf_tableset_t *npf_config_tableset(void);
144 prop_dictionary_t npf_config_dict(void);
145 bool		npf_default_pass(void);
146 
147 int		npf_worker_sysinit(void);
148 void		npf_worker_sysfini(void);
149 void		npf_worker_signal(void);
150 void		npf_worker_register(npf_workfunc_t);
151 void		npf_worker_unregister(npf_workfunc_t);
152 
153 void		npflogattach(int);
154 void		npflogdetach(void);
155 int		npfctl_switch(void *);
156 int		npfctl_reload(u_long, void *);
157 int		npfctl_getconf(u_long, void *);
158 int		npfctl_sessions_save(u_long, void *);
159 int		npfctl_sessions_load(u_long, void *);
160 int		npfctl_rule(u_long, void *);
161 int		npfctl_table(void *);
162 
163 void		npf_stats_inc(npf_stats_t);
164 void		npf_stats_dec(npf_stats_t);
165 
166 /* Packet filter hooks. */
167 int		npf_pfil_register(void);
168 void		npf_pfil_unregister(void);
169 bool		npf_pfil_registered_p(void);
170 int		npf_packet_handler(void *, struct mbuf **, ifnet_t *, int);
171 
172 /* Protocol helpers. */
173 int		npf_cache_all(npf_cache_t *, nbuf_t *);
174 void		npf_recache(npf_cache_t *, nbuf_t *);
175 
176 bool		npf_rwrip(const npf_cache_t *, int, const npf_addr_t *);
177 bool		npf_rwrport(const npf_cache_t *, int, const in_port_t);
178 bool		npf_rwrcksum(const npf_cache_t *, const int,
179 		    const npf_addr_t *, const in_port_t);
180 
181 uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
182 uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
183 uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
184 		    const npf_addr_t *);
185 uint32_t	npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *);
186 int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
187 		    const npf_addr_t *, const npf_netmask_t, const int);
188 void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
189 		    const int, npf_addr_t *);
190 
191 int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
192 		    uint32_t *);
193 bool		npf_fetch_tcpopts(npf_cache_t *, nbuf_t *, uint16_t *, int *);
194 bool		npf_return_block(npf_cache_t *, nbuf_t *, const int);
195 
196 /* Complex instructions. */
197 int		npf_match_ether(nbuf_t *, int, uint16_t, uint32_t *);
198 int		npf_match_proto(const npf_cache_t *, uint32_t);
199 int		npf_match_table(const npf_cache_t *, int, u_int);
200 int		npf_match_ipmask(const npf_cache_t *, int,
201 		    const npf_addr_t *, npf_netmask_t);
202 int		npf_match_tcp_ports(const npf_cache_t *, int, uint32_t);
203 int		npf_match_udp_ports(const npf_cache_t *, int, uint32_t);
204 int		npf_match_icmp4(const npf_cache_t *, uint32_t);
205 int		npf_match_icmp6(const npf_cache_t *, uint32_t);
206 int		npf_match_tcpfl(const npf_cache_t *, uint32_t);
207 
208 /* Tableset interface. */
209 void		npf_tableset_sysinit(void);
210 void		npf_tableset_sysfini(void);
211 
212 extern const pt_tree_ops_t npf_table_ptree_ops;
213 
214 npf_tableset_t *npf_tableset_create(void);
215 void		npf_tableset_destroy(npf_tableset_t *);
216 int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
217 void		npf_tableset_reload(npf_tableset_t *, npf_tableset_t *);
218 
219 npf_table_t *	npf_table_create(u_int, int, size_t);
220 void		npf_table_destroy(npf_table_t *);
221 
222 int		npf_table_check(const npf_tableset_t *, u_int, int);
223 int		npf_table_insert(npf_tableset_t *, u_int,
224 		    const int, const npf_addr_t *, const npf_netmask_t);
225 int		npf_table_remove(npf_tableset_t *, u_int,
226 		    const int, const npf_addr_t *, const npf_netmask_t);
227 int		npf_table_lookup(npf_tableset_t *, u_int,
228 		    const int, const npf_addr_t *);
229 int		npf_table_list(npf_tableset_t *, u_int, void *, size_t);
230 int		npf_table_flush(npf_tableset_t *, u_int);
231 
232 /* Ruleset interface. */
233 npf_ruleset_t *	npf_ruleset_create(size_t);
234 void		npf_ruleset_destroy(npf_ruleset_t *);
235 void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
236 void		npf_ruleset_reload(npf_ruleset_t *, npf_ruleset_t *);
237 void		npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *);
238 npf_rule_t *	npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
239 npf_rule_t *	npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
240 void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
241 
242 int		npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
243 int		npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
244 int		npf_ruleset_remkey(npf_ruleset_t *, const char *,
245 		    const void *, size_t);
246 prop_dictionary_t npf_ruleset_list(npf_ruleset_t *, const char *);
247 int		npf_ruleset_flush(npf_ruleset_t *, const char *);
248 void		npf_ruleset_gc(npf_ruleset_t *);
249 
250 npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, nbuf_t *,
251 		    const npf_ruleset_t *, const int, const int);
252 int		npf_rule_conclude(const npf_rule_t *, int *);
253 
254 /* Rule interface. */
255 npf_rule_t *	npf_rule_alloc(prop_dictionary_t);
256 void		npf_rule_setcode(npf_rule_t *, int, void *, size_t);
257 void		npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
258 void		npf_rule_free(npf_rule_t *);
259 uint64_t	npf_rule_getid(const npf_rule_t *);
260 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
261 void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
262 npf_rproc_t *	npf_rule_getrproc(npf_rule_t *);
263 
264 void		npf_ext_sysinit(void);
265 void		npf_ext_sysfini(void);
266 int		npf_ext_construct(const char *,
267 		    npf_rproc_t *, prop_dictionary_t);
268 
269 npf_rprocset_t *npf_rprocset_create(void);
270 void		npf_rprocset_destroy(npf_rprocset_t *);
271 npf_rproc_t *	npf_rprocset_lookup(npf_rprocset_t *, const char *);
272 void		npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
273 
274 npf_rproc_t *	npf_rproc_create(prop_dictionary_t);
275 void		npf_rproc_acquire(npf_rproc_t *);
276 void		npf_rproc_release(npf_rproc_t *);
277 void		npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int *);
278 
279 /* Session handling interface. */
280 void		npf_session_sysinit(void);
281 void		npf_session_sysfini(void);
282 void		npf_session_tracking(bool);
283 
284 npf_sehash_t *	sess_htable_create(void);
285 void		sess_htable_destroy(npf_sehash_t *);
286 
287 npf_session_t *	npf_session_lookup(const npf_cache_t *, const nbuf_t *,
288 		    const int, bool *);
289 npf_session_t *	npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
290 npf_session_t *	npf_session_establish(npf_cache_t *, nbuf_t *, const int);
291 void		npf_session_release(npf_session_t *);
292 void		npf_session_expire(npf_session_t *);
293 bool		npf_session_pass(const npf_session_t *, npf_rproc_t **);
294 void		npf_session_setpass(npf_session_t *, npf_rproc_t *);
295 int		npf_session_setnat(npf_session_t *, npf_nat_t *, const int);
296 npf_nat_t *	npf_session_retnat(npf_session_t *, const int, bool *);
297 
298 void		npf_session_load(npf_sehash_t *);
299 int		npf_session_save(prop_array_t, prop_array_t);
300 int		npf_session_restore(npf_sehash_t *, prop_dictionary_t);
301 
302 /* State handling. */
303 bool		npf_state_init(npf_cache_t *, nbuf_t *, npf_state_t *);
304 bool		npf_state_inspect(npf_cache_t *, nbuf_t *, npf_state_t *,
305 		    const bool);
306 int		npf_state_etime(const npf_state_t *, const int);
307 void		npf_state_destroy(npf_state_t *);
308 
309 bool		npf_state_tcp(npf_cache_t *, nbuf_t *, npf_state_t *, int);
310 int		npf_state_tcp_timeout(const npf_state_t *);
311 
312 /* NAT. */
313 void		npf_nat_sysinit(void);
314 void		npf_nat_sysfini(void);
315 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
316 void		npf_nat_freepolicy(npf_natpolicy_t *);
317 bool		npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
318 bool		npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
319 void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
320 
321 int		npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, const int);
322 int		npf_nat_translate(npf_cache_t *, nbuf_t *, npf_nat_t *,
323 		    const bool, const int);
324 void		npf_nat_expire(npf_nat_t *);
325 void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
326 void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
327 void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
328 
329 int		npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
330 npf_nat_t *	npf_nat_restore(prop_dictionary_t, npf_session_t *);
331 
332 /* ALG interface. */
333 void		npf_alg_sysinit(void);
334 void		npf_alg_sysfini(void);
335 npf_alg_t *	npf_alg_register(const char *, npf_alg_func_t, npf_alg_func_t,
336 		    npf_alg_sfunc_t);
337 int		npf_alg_unregister(npf_alg_t *);
338 npf_alg_t *	npf_alg_construct(const char *);
339 bool		npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
340 void		npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
341 npf_session_t *	npf_alg_session(npf_cache_t *, nbuf_t *, int);
342 
343 /* Debugging routines. */
344 void		npf_addr_dump(const npf_addr_t *);
345 void		npf_rulenc_dump(const npf_rule_t *);
346 void		npf_sessions_dump(void);
347 void		npf_state_dump(const npf_state_t *);
348 void		npf_nat_dump(const npf_nat_t *);
349 void		npf_state_setsampler(void (*)(npf_state_t *, bool));
350 
351 #endif	/* _NPF_IMPL_H_ */
352