npf_impl.h revision 1.18 1 /* $NetBSD: npf_impl.h,v 1.18 2012/07/15 00:23:00 rmind Exp $ */
2
3 /*-
4 * Copyright (c) 2009-2012 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_nat;
74 struct npf_session;
75
76 typedef struct npf_ruleset npf_ruleset_t;
77 typedef struct npf_rule npf_rule_t;
78 typedef struct npf_nat npf_nat_t;
79 typedef struct npf_alg npf_alg_t;
80 typedef struct npf_natpolicy npf_natpolicy_t;
81 typedef struct npf_session npf_session_t;
82
83 struct npf_sehash;
84 struct npf_tblent;
85 struct npf_table;
86
87 typedef struct npf_sehash npf_sehash_t;
88 typedef struct npf_tblent npf_tblent_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 #define NPF_DECISION_BLOCK 0
98 #define NPF_DECISION_PASS 1
99
100 typedef bool (*npf_algfunc_t)(npf_cache_t *, nbuf_t *, void *);
101
102 #define NPF_NCODE_LIMIT 1024
103 #define NPF_TABLE_SLOTS 32
104
105 /*
106 * SESSION STATE STRUCTURES
107 */
108
109 #define NPF_FLOW_FORW 0
110 #define NPF_FLOW_BACK 1
111
112 typedef struct {
113 uint32_t nst_end;
114 uint32_t nst_maxend;
115 uint32_t nst_maxwin;
116 int nst_wscale;
117 } npf_tcpstate_t;
118
119 typedef struct {
120 kmutex_t nst_lock;
121 int nst_state;
122 npf_tcpstate_t nst_tcpst[2];
123 } npf_state_t;
124
125 #if defined(_NPF_TESTING)
126 void npf_state_sample(npf_state_t *, bool);
127 #define NPF_TCP_STATE_SAMPLE(n, r) npf_state_sample(n, r)
128 #else
129 #define NPF_TCP_STATE_SAMPLE(n, r)
130 #endif
131
132 /*
133 * INTERFACES.
134 */
135
136 /* NPF control, statistics, etc. */
137 void npf_core_enter(void);
138 npf_ruleset_t * npf_core_ruleset(void);
139 npf_ruleset_t * npf_core_natset(void);
140 npf_tableset_t *npf_core_tableset(void);
141 void npf_core_exit(void);
142 bool npf_core_locked(void);
143 bool npf_default_pass(void);
144 prop_dictionary_t npf_core_dict(void);
145
146 void npf_reload(prop_dictionary_t, npf_ruleset_t *,
147 npf_tableset_t *, npf_ruleset_t *, bool);
148
149 void npflogattach(int);
150 void npflogdetach(void);
151 int npfctl_switch(void *);
152 int npfctl_reload(u_long, void *);
153 int npfctl_getconf(u_long, void *);
154 int npfctl_sessions_save(u_long, void *);
155 int npfctl_sessions_load(u_long, void *);
156 int npfctl_update_rule(u_long, void *);
157 int npfctl_table(void *);
158
159 void npf_stats_inc(npf_stats_t);
160 void npf_stats_dec(npf_stats_t);
161
162 /* Packet filter hooks. */
163 int npf_pfil_register(void);
164 void npf_pfil_unregister(void);
165 bool npf_pfil_registered_p(void);
166 int npf_packet_handler(void *, struct mbuf **, ifnet_t *, int);
167 void npf_log_packet(npf_cache_t *, nbuf_t *, int);
168
169 /* Protocol helpers. */
170 bool npf_fetch_ip(npf_cache_t *, nbuf_t *, void *);
171 bool npf_fetch_tcp(npf_cache_t *, nbuf_t *, void *);
172 bool npf_fetch_udp(npf_cache_t *, nbuf_t *, void *);
173 bool npf_fetch_icmp(npf_cache_t *, nbuf_t *, void *);
174 int npf_cache_all(npf_cache_t *, nbuf_t *);
175
176 bool npf_rwrip(npf_cache_t *, nbuf_t *, void *, const int,
177 npf_addr_t *);
178 bool npf_rwrport(npf_cache_t *, nbuf_t *, void *, const int,
179 in_port_t);
180 bool npf_rwrcksum(npf_cache_t *, nbuf_t *, void *, const int,
181 npf_addr_t *, in_port_t);
182
183 uint16_t npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
184 uint16_t npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
185 uint16_t npf_addr_cksum(uint16_t, int, npf_addr_t *, npf_addr_t *);
186 uint32_t npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *);
187 int npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
188 const npf_addr_t *, const npf_netmask_t, const int);
189 void npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
190 const int, npf_addr_t *);
191
192 int npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
193 uint32_t *);
194 bool npf_fetch_tcpopts(const npf_cache_t *, nbuf_t *,
195 uint16_t *, int *);
196 bool npf_normalize(npf_cache_t *, nbuf_t *, bool, bool, u_int, u_int);
197 bool npf_return_block(npf_cache_t *, nbuf_t *, const int);
198
199 /* Complex instructions. */
200 int npf_match_ether(nbuf_t *, int, int, uint16_t, uint32_t *);
201 int npf_match_proto(npf_cache_t *, nbuf_t *, void *, uint32_t);
202 int npf_match_table(npf_cache_t *, nbuf_t *, void *,
203 const int, const u_int);
204 int npf_match_ipmask(npf_cache_t *, nbuf_t *, void *,
205 const int, const npf_addr_t *, const npf_netmask_t);
206 int npf_match_tcp_ports(npf_cache_t *, nbuf_t *, void *,
207 const int, const uint32_t);
208 int npf_match_udp_ports(npf_cache_t *, nbuf_t *, void *,
209 const int, const uint32_t);
210 int npf_match_icmp4(npf_cache_t *, nbuf_t *, void *, uint32_t);
211 int npf_match_tcpfl(npf_cache_t *, nbuf_t *, void *, uint32_t);
212
213 /* Tableset interface. */
214 void npf_tableset_sysinit(void);
215 void npf_tableset_sysfini(void);
216
217 const pt_tree_ops_t npf_table_ptree_ops;
218
219 npf_tableset_t *npf_tableset_create(void);
220 void npf_tableset_destroy(npf_tableset_t *);
221 int npf_tableset_insert(npf_tableset_t *, npf_table_t *);
222 npf_tableset_t *npf_tableset_reload(npf_tableset_t *);
223
224 npf_table_t * npf_table_create(u_int, int, size_t);
225 void npf_table_destroy(npf_table_t *);
226 void npf_table_ref(npf_table_t *);
227 void npf_table_unref(npf_table_t *);
228
229 npf_table_t * npf_table_get(npf_tableset_t *, u_int);
230 void npf_table_put(npf_table_t *);
231 int npf_table_check(const npf_tableset_t *, u_int, int);
232 int npf_table_insert(npf_tableset_t *, u_int,
233 const int, const npf_addr_t *, const npf_netmask_t);
234 int npf_table_remove(npf_tableset_t *, u_int,
235 const int, const npf_addr_t *, const npf_netmask_t);
236 int npf_table_lookup(npf_tableset_t *, u_int,
237 const int, const npf_addr_t *);
238
239 /* Ruleset interface. */
240 npf_ruleset_t * npf_ruleset_create(void);
241 void npf_ruleset_destroy(npf_ruleset_t *);
242 void npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
243 void npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *);
244 npf_rule_t * npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
245 npf_rule_t * npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
246 npf_rule_t * npf_ruleset_replace(const char *, npf_ruleset_t *);
247 void npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
248
249 npf_rule_t * npf_ruleset_inspect(npf_cache_t *, nbuf_t *, npf_ruleset_t *,
250 ifnet_t *, const int, const int);
251 int npf_rule_apply(npf_cache_t *, nbuf_t *, npf_rule_t *, int *);
252
253 /* Rule interface. */
254 npf_rule_t * npf_rule_alloc(prop_dictionary_t, npf_rproc_t *, void *, size_t);
255 void npf_rule_free(npf_rule_t *);
256 npf_ruleset_t * npf_rule_subset(npf_rule_t *);
257 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
258 void npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
259 npf_rproc_t * npf_rule_getrproc(npf_rule_t *);
260
261 npf_rproc_t * npf_rproc_create(prop_dictionary_t);
262 void npf_rproc_acquire(npf_rproc_t *);
263 void npf_rproc_release(npf_rproc_t *);
264 void npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int);
265
266 /* Session handling interface. */
267 void npf_session_sysinit(void);
268 void npf_session_sysfini(void);
269 int npf_session_tracking(bool);
270
271 npf_sehash_t * sess_htable_create(void);
272 void sess_htable_destroy(npf_sehash_t *);
273 void sess_htable_reload(npf_sehash_t *);
274
275 npf_session_t * npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
276 npf_session_t * npf_session_establish(const npf_cache_t *, nbuf_t *, const int);
277 void npf_session_release(npf_session_t *);
278 void npf_session_expire(npf_session_t *);
279 bool npf_session_pass(const npf_session_t *, npf_rproc_t **);
280 void npf_session_setpass(npf_session_t *, npf_rproc_t *);
281 int npf_session_setnat(npf_session_t *, npf_nat_t *, const int);
282 npf_nat_t * npf_session_retnat(npf_session_t *, const int, bool *);
283
284 int npf_session_save(prop_array_t, prop_array_t);
285 int npf_session_restore(npf_sehash_t *, prop_dictionary_t);
286
287 /* State handling. */
288 bool npf_state_init(const npf_cache_t *, nbuf_t *, npf_state_t *);
289 bool npf_state_inspect(const npf_cache_t *, nbuf_t *, npf_state_t *,
290 const bool);
291 int npf_state_etime(const npf_state_t *, const int);
292 void npf_state_destroy(npf_state_t *);
293
294 bool npf_state_tcp(const npf_cache_t *, nbuf_t *, npf_state_t *, int);
295 int npf_state_tcp_timeout(const npf_state_t *);
296
297 /* NAT. */
298 void npf_nat_sysinit(void);
299 void npf_nat_sysfini(void);
300 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
301 void npf_nat_freepolicy(npf_natpolicy_t *);
302 bool npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
303 bool npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
304 void npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
305
306 int npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *,
307 ifnet_t *, const int);
308 void npf_nat_expire(npf_nat_t *);
309 void npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
310 void npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
311 void npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
312
313 int npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
314 npf_nat_t * npf_nat_restore(prop_dictionary_t, npf_session_t *);
315
316 /* ALG interface. */
317 void npf_alg_sysinit(void);
318 void npf_alg_sysfini(void);
319 npf_alg_t * npf_alg_register(npf_algfunc_t, npf_algfunc_t,
320 npf_algfunc_t, npf_algfunc_t);
321 int npf_alg_unregister(npf_alg_t *);
322 bool npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *);
323 void npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, const int );
324 bool npf_alg_sessionid(npf_cache_t *, nbuf_t *, npf_cache_t *);
325
326 /* Debugging routines. */
327 void npf_addr_dump(const npf_addr_t *);
328 void npf_rulenc_dump(const npf_rule_t *);
329 void npf_sessions_dump(void);
330 void npf_state_dump(const npf_state_t *);
331 void npf_nat_dump(const npf_nat_t *);
332
333 #endif /* _NPF_IMPL_H_ */
334