npf_impl.h revision 1.10 1 /* $NetBSD: npf_impl.h,v 1.10 2012/02/06 23:30:14 rmind Exp $ */
2
3 /*-
4 * Copyright (c) 2009-2011 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) && !defined(_NPF_TESTING)
41 #error "Kernel-level header only"
42 #endif
43
44 #include <sys/types.h>
45 #include <sys/queue.h>
46 #include <sys/hash.h>
47 #include <sys/rbtree.h>
48 #include <sys/rwlock.h>
49 #include <net/if.h>
50
51 #include "npf.h"
52 #include "npf_ncode.h"
53
54 #ifdef _NPF_TESTING
55 #include "testing.h"
56 #endif
57
58 #ifdef _NPF_DEBUG
59 #define NPF_PRINTF(x) printf x
60 #else
61 #define NPF_PRINTF(x)
62 #endif
63
64 /*
65 * STRUCTURE DECLARATIONS.
66 */
67
68 struct npf_ruleset;
69 struct npf_rule;
70 struct npf_nat;
71 struct npf_session;
72
73 typedef struct npf_ruleset npf_ruleset_t;
74 typedef struct npf_rule npf_rule_t;
75 typedef struct npf_nat npf_nat_t;
76 typedef struct npf_alg npf_alg_t;
77 typedef struct npf_natpolicy npf_natpolicy_t;
78 typedef struct npf_session npf_session_t;
79
80 struct npf_sehash;
81 struct npf_tblent;
82 struct npf_table;
83
84 typedef struct npf_sehash npf_sehash_t;
85 typedef struct npf_tblent npf_tblent_t;
86 typedef struct npf_table npf_table_t;
87
88 typedef npf_table_t * npf_tableset_t;
89
90 /*
91 * DEFINITIONS.
92 */
93
94 typedef bool (*npf_algfunc_t)(npf_cache_t *, nbuf_t *, void *);
95
96 #define NPF_NCODE_LIMIT 1024
97 #define NPF_TABLE_SLOTS 32
98
99 /*
100 * SESSION STATE STRUCTURES
101 */
102
103 #define NPF_FLOW_FORW 0
104 #define NPF_FLOW_BACK 1
105
106 typedef struct {
107 uint32_t nst_end;
108 uint32_t nst_maxend;
109 uint32_t nst_maxwin;
110 int nst_wscale;
111 } npf_tcpstate_t;
112
113 typedef struct {
114 kmutex_t nst_lock;
115 int nst_state;
116 npf_tcpstate_t nst_tcpst[2];
117 } npf_state_t;
118
119 /*
120 * INTERFACES.
121 */
122
123 /* NPF control, statistics, etc. */
124 void npf_core_enter(void);
125 npf_ruleset_t * npf_core_ruleset(void);
126 npf_ruleset_t * npf_core_natset(void);
127 npf_tableset_t *npf_core_tableset(void);
128 void npf_core_exit(void);
129 bool npf_core_locked(void);
130 void npf_reload(npf_ruleset_t *, npf_tableset_t *, npf_ruleset_t *);
131
132 void npflogattach(int);
133 void npflogdetach(void);
134 int npfctl_switch(void *);
135 int npfctl_reload(u_long, void *);
136 int npfctl_sessions_save(u_long, void *);
137 int npfctl_sessions_load(u_long, void *);
138 int npfctl_update_rule(u_long, void *);
139 int npfctl_table(void *);
140
141 void npf_stats_inc(npf_stats_t);
142 void npf_stats_dec(npf_stats_t);
143
144 /* Packet filter hooks. */
145 int npf_register_pfil(void);
146 void npf_unregister_pfil(void);
147 void npf_log_packet(npf_cache_t *, nbuf_t *, int);
148
149 /* Protocol helpers. */
150 bool npf_fetch_ip(npf_cache_t *, nbuf_t *, void *);
151 bool npf_fetch_tcp(npf_cache_t *, nbuf_t *, void *);
152 bool npf_fetch_udp(npf_cache_t *, nbuf_t *, void *);
153 bool npf_fetch_icmp(npf_cache_t *, nbuf_t *, void *);
154 int npf_cache_all(npf_cache_t *, nbuf_t *);
155
156 bool npf_rwrip(npf_cache_t *, nbuf_t *, void *, const int,
157 npf_addr_t *);
158 bool npf_rwrport(npf_cache_t *, nbuf_t *, void *, const int,
159 in_port_t);
160 bool npf_rwrcksum(npf_cache_t *, nbuf_t *, void *, const int,
161 npf_addr_t *, in_port_t);
162
163 uint16_t npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
164 uint16_t npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
165 uint16_t npf_addr_cksum(uint16_t, int, npf_addr_t *, npf_addr_t *);
166 uint32_t npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *);
167 int npf_tcpsaw(npf_cache_t *, tcp_seq *, tcp_seq *, uint32_t *);
168 bool npf_fetch_tcpopts(const npf_cache_t *, nbuf_t *,
169 uint16_t *, int *);
170 bool npf_normalize(npf_cache_t *, nbuf_t *, bool, bool, u_int, u_int);
171 void npf_return_block(npf_cache_t *, nbuf_t *, const int);
172
173 /* Complex instructions. */
174 int npf_match_ether(nbuf_t *, int, int, uint16_t, uint32_t *);
175 int npf_match_table(npf_cache_t *, nbuf_t *, void *,
176 const int, const u_int);
177 int npf_match_ipmask(npf_cache_t *, nbuf_t *, void *,
178 const int, const npf_addr_t *, const npf_netmask_t);
179 int npf_match_tcp_ports(npf_cache_t *, nbuf_t *, void *,
180 const int, const uint32_t);
181 int npf_match_udp_ports(npf_cache_t *, nbuf_t *, void *,
182 const int, const uint32_t);
183 int npf_match_icmp4(npf_cache_t *, nbuf_t *, void *, uint32_t);
184 int npf_match_tcpfl(npf_cache_t *, nbuf_t *, void *, uint32_t);
185
186 /* Tableset interface. */
187 void npf_tableset_sysinit(void);
188 void npf_tableset_sysfini(void);
189
190 npf_tableset_t *npf_tableset_create(void);
191 void npf_tableset_destroy(npf_tableset_t *);
192 int npf_tableset_insert(npf_tableset_t *, npf_table_t *);
193 npf_tableset_t *npf_tableset_reload(npf_tableset_t *);
194
195 npf_table_t * npf_table_create(u_int, int, size_t);
196 void npf_table_destroy(npf_table_t *);
197 void npf_table_ref(npf_table_t *);
198 void npf_table_unref(npf_table_t *);
199
200 npf_table_t * npf_table_get(npf_tableset_t *, u_int);
201 void npf_table_put(npf_table_t *);
202 int npf_table_check(npf_tableset_t *, u_int, int);
203 int npf_table_add_cidr(npf_tableset_t *, u_int,
204 const npf_addr_t *, const npf_netmask_t);
205 int npf_table_rem_cidr(npf_tableset_t *, u_int,
206 const npf_addr_t *, const npf_netmask_t);
207 int npf_table_match_addr(npf_tableset_t *, u_int,
208 const npf_addr_t *);
209
210 /* Ruleset interface. */
211 npf_ruleset_t * npf_ruleset_create(void);
212 void npf_ruleset_destroy(npf_ruleset_t *);
213 void npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
214 void npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *);
215 npf_rule_t * npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
216 npf_rule_t * npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
217 npf_rule_t * npf_ruleset_replace(const char *, npf_ruleset_t *);
218
219 npf_rule_t * npf_ruleset_inspect(npf_cache_t *, nbuf_t *, npf_ruleset_t *,
220 ifnet_t *, const int, const int);
221 int npf_rule_apply(npf_cache_t *, nbuf_t *, npf_rule_t *, int *);
222
223 /* Rule interface. */
224 npf_rule_t * npf_rule_alloc(prop_dictionary_t, npf_rproc_t *, void *, size_t);
225 void npf_rule_free(npf_rule_t *);
226 npf_ruleset_t * npf_rule_subset(npf_rule_t *);
227 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
228 void npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
229 npf_rproc_t * npf_rule_getrproc(npf_rule_t *);
230
231 npf_rproc_t * npf_rproc_create(prop_dictionary_t);
232 void npf_rproc_acquire(npf_rproc_t *);
233 void npf_rproc_release(npf_rproc_t *);
234 void npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int);
235
236 /* Session handling interface. */
237 void npf_session_sysinit(void);
238 void npf_session_sysfini(void);
239 int npf_session_tracking(bool);
240
241 npf_sehash_t * sess_htable_create(void);
242 void sess_htable_destroy(npf_sehash_t *);
243 void sess_htable_reload(npf_sehash_t *);
244
245 npf_session_t * npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
246 npf_session_t * npf_session_establish(const npf_cache_t *, nbuf_t *, const int);
247 void npf_session_release(npf_session_t *);
248 void npf_session_expire(npf_session_t *);
249 bool npf_session_pass(const npf_session_t *, npf_rproc_t **);
250 void npf_session_setpass(npf_session_t *, npf_rproc_t *);
251 int npf_session_setnat(npf_session_t *, npf_nat_t *, const int);
252 npf_nat_t * npf_session_retnat(npf_session_t *, const int, bool *);
253
254 int npf_session_save(prop_array_t, prop_array_t);
255 int npf_session_restore(npf_sehash_t *, prop_dictionary_t);
256
257 /* State handling. */
258 bool npf_state_init(const npf_cache_t *, nbuf_t *, npf_state_t *);
259 bool npf_state_inspect(const npf_cache_t *, nbuf_t *, npf_state_t *,
260 const bool);
261 int npf_state_etime(const npf_state_t *, const int);
262 void npf_state_destroy(npf_state_t *);
263
264 bool npf_state_tcp(const npf_cache_t *, nbuf_t *, npf_state_t *, int);
265 int npf_state_tcp_timeout(const npf_state_t *);
266
267 /* NAT. */
268 void npf_nat_sysinit(void);
269 void npf_nat_sysfini(void);
270 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
271 void npf_nat_freepolicy(npf_natpolicy_t *);
272 bool npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
273 bool npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
274
275 int npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *,
276 ifnet_t *, const int);
277 void npf_nat_expire(npf_nat_t *);
278 void npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
279 void npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
280 void npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
281
282 int npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
283 npf_nat_t * npf_nat_restore(prop_dictionary_t, npf_session_t *);
284
285 /* ALG interface. */
286 void npf_alg_sysinit(void);
287 void npf_alg_sysfini(void);
288 npf_alg_t * npf_alg_register(npf_algfunc_t, npf_algfunc_t,
289 npf_algfunc_t, npf_algfunc_t);
290 int npf_alg_unregister(npf_alg_t *);
291 bool npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *);
292 void npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, const int );
293 bool npf_alg_sessionid(npf_cache_t *, nbuf_t *, npf_cache_t *);
294
295 /* Debugging routines. */
296 void npf_rulenc_dump(npf_rule_t *);
297 void npf_sessions_dump(void);
298 void npf_state_dump(npf_state_t *);
299 void npf_nat_dump(npf_nat_t *);
300
301 #endif /* _NPF_IMPL_H_ */
302