npf_impl.h revision 1.28 1 /* $NetBSD: npf_impl.h,v 1.28 2013/02/16 21:11:12 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
100 #define NPF_NCODE_LIMIT 1024
101 #define NPF_TABLE_SLOTS 32
102
103 /*
104 * SESSION STATE STRUCTURES
105 */
106
107 #define NPF_FLOW_FORW 0
108 #define NPF_FLOW_BACK 1
109
110 typedef struct {
111 uint32_t nst_end;
112 uint32_t nst_maxend;
113 uint32_t nst_maxwin;
114 int nst_wscale;
115 } npf_tcpstate_t;
116
117 typedef struct {
118 kmutex_t nst_lock;
119 int nst_state;
120 npf_tcpstate_t nst_tcpst[2];
121 } npf_state_t;
122
123 /*
124 * INTERFACES.
125 */
126
127 /* NPF config, statistics, etc. */
128 void npf_config_init(void);
129 void npf_config_fini(void);
130
131 void npf_config_enter(void);
132 void npf_config_exit(void);
133 void npf_config_sync(void);
134 bool npf_config_locked_p(void);
135 int npf_config_read_enter(void);
136 void npf_config_read_exit(int);
137
138 void npf_config_reload(prop_dictionary_t, npf_ruleset_t *,
139 npf_tableset_t *, npf_ruleset_t *, npf_rprocset_t *, bool);
140 npf_ruleset_t * npf_config_ruleset(void);
141 npf_ruleset_t * npf_config_natset(void);
142 npf_tableset_t *npf_config_tableset(void);
143 prop_dictionary_t npf_config_dict(void);
144 bool npf_default_pass(void);
145
146 void npflogattach(int);
147 void npflogdetach(void);
148 int npfctl_switch(void *);
149 int npfctl_reload(u_long, void *);
150 int npfctl_getconf(u_long, void *);
151 int npfctl_sessions_save(u_long, void *);
152 int npfctl_sessions_load(u_long, void *);
153 int npfctl_rule(u_long, void *);
154 int npfctl_table(void *);
155
156 void npf_stats_inc(npf_stats_t);
157 void npf_stats_dec(npf_stats_t);
158
159 /* Packet filter hooks. */
160 int npf_pfil_register(void);
161 void npf_pfil_unregister(void);
162 bool npf_pfil_registered_p(void);
163 int npf_packet_handler(void *, struct mbuf **, ifnet_t *, int);
164
165 /* Protocol helpers. */
166 int npf_cache_all(npf_cache_t *, nbuf_t *);
167 void npf_recache(npf_cache_t *, nbuf_t *);
168
169 bool npf_rwrip(const npf_cache_t *, int, const npf_addr_t *);
170 bool npf_rwrport(const npf_cache_t *, int, const in_port_t);
171 bool npf_rwrcksum(const npf_cache_t *, const int,
172 const npf_addr_t *, const in_port_t);
173
174 uint16_t npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
175 uint16_t npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
176 uint16_t npf_addr_cksum(uint16_t, int, const npf_addr_t *,
177 const npf_addr_t *);
178 uint32_t npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *);
179 int npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
180 const npf_addr_t *, const npf_netmask_t, const int);
181 void npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
182 const int, npf_addr_t *);
183
184 int npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
185 uint32_t *);
186 bool npf_fetch_tcpopts(npf_cache_t *, nbuf_t *, uint16_t *, int *);
187 bool npf_return_block(npf_cache_t *, nbuf_t *, const int);
188
189 /* Complex instructions. */
190 int npf_match_ether(nbuf_t *, int, uint16_t, uint32_t *);
191 int npf_match_proto(const npf_cache_t *, uint32_t);
192 int npf_match_table(const npf_cache_t *, int, u_int);
193 int npf_match_ipmask(const npf_cache_t *, int,
194 const npf_addr_t *, npf_netmask_t);
195 int npf_match_tcp_ports(const npf_cache_t *, int, uint32_t);
196 int npf_match_udp_ports(const npf_cache_t *, int, uint32_t);
197 int npf_match_icmp4(const npf_cache_t *, uint32_t);
198 int npf_match_icmp6(const npf_cache_t *, uint32_t);
199 int npf_match_tcpfl(const npf_cache_t *, uint32_t);
200
201 /* Tableset interface. */
202 void npf_tableset_sysinit(void);
203 void npf_tableset_sysfini(void);
204
205 extern const pt_tree_ops_t npf_table_ptree_ops;
206
207 npf_tableset_t *npf_tableset_create(void);
208 void npf_tableset_destroy(npf_tableset_t *);
209 int npf_tableset_insert(npf_tableset_t *, npf_table_t *);
210 void npf_tableset_reload(npf_tableset_t *, npf_tableset_t *);
211
212 npf_table_t * npf_table_create(u_int, int, size_t);
213 void npf_table_destroy(npf_table_t *);
214
215 int npf_table_check(const npf_tableset_t *, u_int, int);
216 int npf_table_insert(npf_tableset_t *, u_int,
217 const int, const npf_addr_t *, const npf_netmask_t);
218 int npf_table_remove(npf_tableset_t *, u_int,
219 const int, const npf_addr_t *, const npf_netmask_t);
220 int npf_table_lookup(npf_tableset_t *, u_int,
221 const int, const npf_addr_t *);
222 int npf_table_list(npf_tableset_t *, u_int, void *, size_t);
223
224 /* Ruleset interface. */
225 npf_ruleset_t * npf_ruleset_create(size_t);
226 void npf_ruleset_destroy(npf_ruleset_t *);
227 void npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
228 void npf_ruleset_reload(npf_ruleset_t *, npf_ruleset_t *);
229 void npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *);
230 npf_rule_t * npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
231 npf_rule_t * npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
232 void npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
233
234 int npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
235 int npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
236 int npf_ruleset_remkey(npf_ruleset_t *, const char *,
237 const void *, size_t);
238 prop_dictionary_t npf_ruleset_list(npf_ruleset_t *, const char *);
239 int npf_ruleset_flush(npf_ruleset_t *, const char *);
240 void npf_ruleset_gc(npf_ruleset_t *);
241
242 npf_rule_t * npf_ruleset_inspect(npf_cache_t *, nbuf_t *,
243 const npf_ruleset_t *, const int, const int);
244 int npf_rule_conclude(const npf_rule_t *, int *);
245
246 /* Rule interface. */
247 npf_rule_t * npf_rule_alloc(prop_dictionary_t);
248 void npf_rule_setcode(npf_rule_t *, int, void *, size_t);
249 void npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
250 void npf_rule_free(npf_rule_t *);
251 uint64_t npf_rule_getid(const npf_rule_t *);
252 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
253 void npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
254 npf_rproc_t * npf_rule_getrproc(npf_rule_t *);
255
256 void npf_ext_sysinit(void);
257 void npf_ext_sysfini(void);
258 int npf_ext_construct(const char *,
259 npf_rproc_t *, prop_dictionary_t);
260
261 npf_rprocset_t *npf_rprocset_create(void);
262 void npf_rprocset_destroy(npf_rprocset_t *);
263 npf_rproc_t * npf_rprocset_lookup(npf_rprocset_t *, const char *);
264 void npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
265
266 npf_rproc_t * npf_rproc_create(prop_dictionary_t);
267 void npf_rproc_acquire(npf_rproc_t *);
268 void npf_rproc_release(npf_rproc_t *);
269 void npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int *);
270
271 /* Session handling interface. */
272 void npf_session_sysinit(void);
273 void npf_session_sysfini(void);
274 int npf_session_tracking(bool);
275
276 npf_sehash_t * sess_htable_create(void);
277 void sess_htable_destroy(npf_sehash_t *);
278 void sess_htable_reload(npf_sehash_t *);
279
280 npf_session_t * npf_session_lookup(const npf_cache_t *, const nbuf_t *,
281 const int, bool *);
282 npf_session_t * npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
283 npf_session_t * npf_session_establish(npf_cache_t *, nbuf_t *, const int);
284 void npf_session_release(npf_session_t *);
285 void npf_session_expire(npf_session_t *);
286 bool npf_session_pass(const npf_session_t *, npf_rproc_t **);
287 void npf_session_setpass(npf_session_t *, npf_rproc_t *);
288 int npf_session_setnat(npf_session_t *, npf_nat_t *, const int);
289 npf_nat_t * npf_session_retnat(npf_session_t *, const int, bool *);
290
291 int npf_session_save(prop_array_t, prop_array_t);
292 int npf_session_restore(npf_sehash_t *, prop_dictionary_t);
293
294 /* State handling. */
295 bool npf_state_init(npf_cache_t *, nbuf_t *, npf_state_t *);
296 bool npf_state_inspect(npf_cache_t *, nbuf_t *, npf_state_t *,
297 const bool);
298 int npf_state_etime(const npf_state_t *, const int);
299 void npf_state_destroy(npf_state_t *);
300
301 bool npf_state_tcp(npf_cache_t *, nbuf_t *, npf_state_t *, int);
302 int npf_state_tcp_timeout(const npf_state_t *);
303
304 /* NAT. */
305 void npf_nat_sysinit(void);
306 void npf_nat_sysfini(void);
307 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
308 void npf_nat_freepolicy(npf_natpolicy_t *);
309 bool npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
310 bool npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
311 void npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
312
313 int npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, const int);
314 int npf_nat_translate(npf_cache_t *, nbuf_t *, npf_nat_t *,
315 const bool, const int);
316 void npf_nat_expire(npf_nat_t *);
317 void npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
318 void npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
319 void npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
320
321 int npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
322 npf_nat_t * npf_nat_restore(prop_dictionary_t, npf_session_t *);
323
324 /* ALG interface. */
325 void npf_alg_sysinit(void);
326 void npf_alg_sysfini(void);
327 npf_alg_t * npf_alg_register(npf_alg_func_t, npf_alg_func_t,
328 npf_alg_sfunc_t);
329 int npf_alg_unregister(npf_alg_t *);
330 bool npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
331 void npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
332 npf_session_t * npf_alg_session(npf_cache_t *, nbuf_t *, int);
333
334 /* Debugging routines. */
335 void npf_addr_dump(const npf_addr_t *);
336 void npf_rulenc_dump(const npf_rule_t *);
337 void npf_sessions_dump(void);
338 void npf_state_dump(const npf_state_t *);
339 void npf_nat_dump(const npf_nat_t *);
340 void npf_state_setsampler(void (*)(npf_state_t *, bool));
341
342 #endif /* _NPF_IMPL_H_ */
343