xref: /netbsd-src/sys/net/npf/npf_impl.h (revision 96fc3e30a7c3f7bba53384bf41dad5f78306fac4)
1 /*	$NetBSD: npf_impl.h,v 1.25 2012/12/24 19:05:43 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_table;
85 
86 typedef struct npf_sehash	npf_sehash_t;
87 typedef struct npf_table	npf_table_t;
88 
89 typedef npf_table_t *		npf_tableset_t;
90 
91 /*
92  * DEFINITIONS.
93  */
94 
95 typedef bool (*npf_alg_func_t)(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
96 typedef npf_session_t *(*npf_alg_sfunc_t)(npf_cache_t *, nbuf_t *, int);
97 
98 #define	NPF_NCODE_LIMIT		1024
99 #define	NPF_TABLE_SLOTS		32
100 
101 /*
102  * SESSION STATE STRUCTURES
103  */
104 
105 #define	NPF_FLOW_FORW		0
106 #define	NPF_FLOW_BACK		1
107 
108 typedef struct {
109 	uint32_t	nst_end;
110 	uint32_t	nst_maxend;
111 	uint32_t	nst_maxwin;
112 	int		nst_wscale;
113 } npf_tcpstate_t;
114 
115 typedef struct {
116 	kmutex_t	nst_lock;
117 	int		nst_state;
118 	npf_tcpstate_t	nst_tcpst[2];
119 } npf_state_t;
120 
121 /*
122  * INTERFACES.
123  */
124 
125 /* NPF control, statistics, etc. */
126 void		npf_core_enter(void);
127 npf_ruleset_t *	npf_core_ruleset(void);
128 npf_ruleset_t *	npf_core_natset(void);
129 npf_tableset_t *npf_core_tableset(void);
130 void		npf_core_exit(void);
131 bool		npf_core_locked(void);
132 bool		npf_default_pass(void);
133 prop_dictionary_t npf_core_dict(void);
134 
135 void		npf_reload(prop_dictionary_t, npf_ruleset_t *,
136 		    npf_tableset_t *, npf_ruleset_t *, bool);
137 
138 void		npflogattach(int);
139 void		npflogdetach(void);
140 int		npfctl_switch(void *);
141 int		npfctl_reload(u_long, void *);
142 int		npfctl_getconf(u_long, void *);
143 int		npfctl_sessions_save(u_long, void *);
144 int		npfctl_sessions_load(u_long, void *);
145 int		npfctl_update_rule(u_long, void *);
146 int		npfctl_table(void *);
147 
148 void		npf_stats_inc(npf_stats_t);
149 void		npf_stats_dec(npf_stats_t);
150 
151 /* Packet filter hooks. */
152 int		npf_pfil_register(void);
153 void		npf_pfil_unregister(void);
154 bool		npf_pfil_registered_p(void);
155 int		npf_packet_handler(void *, struct mbuf **, ifnet_t *, int);
156 
157 /* Protocol helpers. */
158 int		npf_cache_all(npf_cache_t *, nbuf_t *);
159 void		npf_recache(npf_cache_t *, nbuf_t *);
160 
161 bool		npf_rwrip(const npf_cache_t *, int, const npf_addr_t *);
162 bool		npf_rwrport(const npf_cache_t *, int, const in_port_t);
163 bool		npf_rwrcksum(const npf_cache_t *, const int,
164 		    const npf_addr_t *, const in_port_t);
165 
166 uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
167 uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
168 uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
169 		    const npf_addr_t *);
170 uint32_t	npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *);
171 int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
172 		    const npf_addr_t *, const npf_netmask_t, const int);
173 void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
174 		    const int, npf_addr_t *);
175 
176 int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
177 		    uint32_t *);
178 bool		npf_fetch_tcpopts(npf_cache_t *, nbuf_t *, uint16_t *, int *);
179 bool		npf_return_block(npf_cache_t *, nbuf_t *, const int);
180 
181 /* Complex instructions. */
182 int		npf_match_ether(nbuf_t *, int, uint16_t, uint32_t *);
183 int		npf_match_proto(const npf_cache_t *, uint32_t);
184 int		npf_match_table(const npf_cache_t *, int, u_int);
185 int		npf_match_ipmask(const npf_cache_t *, int,
186 		    const npf_addr_t *, npf_netmask_t);
187 int		npf_match_tcp_ports(const npf_cache_t *, int, uint32_t);
188 int		npf_match_udp_ports(const npf_cache_t *, int, uint32_t);
189 int		npf_match_icmp4(const npf_cache_t *, uint32_t);
190 int		npf_match_icmp6(const npf_cache_t *, uint32_t);
191 int		npf_match_tcpfl(const npf_cache_t *, uint32_t);
192 
193 /* Tableset interface. */
194 void		npf_tableset_sysinit(void);
195 void		npf_tableset_sysfini(void);
196 
197 extern const pt_tree_ops_t npf_table_ptree_ops;
198 
199 npf_tableset_t *npf_tableset_create(void);
200 void		npf_tableset_destroy(npf_tableset_t *);
201 int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
202 void		npf_tableset_reload(npf_tableset_t *, npf_tableset_t *);
203 
204 npf_table_t *	npf_table_create(u_int, int, size_t);
205 void		npf_table_destroy(npf_table_t *);
206 
207 int		npf_table_check(const npf_tableset_t *, u_int, int);
208 int		npf_table_insert(npf_tableset_t *, u_int,
209 		    const int, const npf_addr_t *, const npf_netmask_t);
210 int		npf_table_remove(npf_tableset_t *, u_int,
211 		    const int, const npf_addr_t *, const npf_netmask_t);
212 int		npf_table_lookup(npf_tableset_t *, u_int,
213 		    const int, const npf_addr_t *);
214 int		npf_table_list(npf_tableset_t *, u_int, void *, size_t);
215 
216 /* Ruleset interface. */
217 npf_ruleset_t *	npf_ruleset_create(void);
218 void		npf_ruleset_destroy(npf_ruleset_t *);
219 void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
220 void		npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *);
221 npf_rule_t *	npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
222 npf_rule_t *	npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
223 npf_rule_t *	npf_ruleset_replace(const char *, npf_ruleset_t *);
224 void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
225 
226 npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, nbuf_t *,
227 		    const npf_ruleset_t *, const int, const int);
228 int		npf_rule_apply(npf_cache_t *, nbuf_t *, npf_rule_t *, int *);
229 
230 /* Rule interface. */
231 npf_rule_t *	npf_rule_alloc(prop_dictionary_t, npf_rproc_t *, void *, size_t);
232 void		npf_rule_free(npf_rule_t *);
233 npf_ruleset_t *	npf_rule_subset(npf_rule_t *);
234 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
235 void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
236 npf_rproc_t *	npf_rule_getrproc(npf_rule_t *);
237 
238 void		npf_ext_sysinit(void);
239 void		npf_ext_sysfini(void);
240 int		npf_ext_construct(const char *,
241 		    npf_rproc_t *, prop_dictionary_t);
242 
243 npf_rproc_t *	npf_rproc_create(prop_dictionary_t);
244 void		npf_rproc_acquire(npf_rproc_t *);
245 void		npf_rproc_release(npf_rproc_t *);
246 void		npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int *);
247 
248 /* Session handling interface. */
249 void		npf_session_sysinit(void);
250 void		npf_session_sysfini(void);
251 int		npf_session_tracking(bool);
252 
253 npf_sehash_t *	sess_htable_create(void);
254 void		sess_htable_destroy(npf_sehash_t *);
255 void		sess_htable_reload(npf_sehash_t *);
256 
257 npf_session_t *	npf_session_lookup(const npf_cache_t *, const nbuf_t *,
258 		    const int, bool *);
259 npf_session_t *	npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
260 npf_session_t *	npf_session_establish(npf_cache_t *, nbuf_t *, const int);
261 void		npf_session_release(npf_session_t *);
262 void		npf_session_expire(npf_session_t *);
263 bool		npf_session_pass(const npf_session_t *, npf_rproc_t **);
264 void		npf_session_setpass(npf_session_t *, npf_rproc_t *);
265 int		npf_session_setnat(npf_session_t *, npf_nat_t *, const int);
266 npf_nat_t *	npf_session_retnat(npf_session_t *, const int, bool *);
267 
268 int		npf_session_save(prop_array_t, prop_array_t);
269 int		npf_session_restore(npf_sehash_t *, prop_dictionary_t);
270 
271 /* State handling. */
272 bool		npf_state_init(npf_cache_t *, nbuf_t *, npf_state_t *);
273 bool		npf_state_inspect(npf_cache_t *, nbuf_t *, npf_state_t *,
274 		    const bool);
275 int		npf_state_etime(const npf_state_t *, const int);
276 void		npf_state_destroy(npf_state_t *);
277 
278 bool		npf_state_tcp(npf_cache_t *, nbuf_t *, npf_state_t *, int);
279 int		npf_state_tcp_timeout(const npf_state_t *);
280 
281 /* NAT. */
282 void		npf_nat_sysinit(void);
283 void		npf_nat_sysfini(void);
284 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
285 void		npf_nat_freepolicy(npf_natpolicy_t *);
286 bool		npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
287 bool		npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
288 void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
289 
290 int		npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, const int);
291 int		npf_nat_translate(npf_cache_t *, nbuf_t *, npf_nat_t *,
292 		    const bool, const int);
293 void		npf_nat_expire(npf_nat_t *);
294 void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
295 void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
296 void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
297 
298 int		npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
299 npf_nat_t *	npf_nat_restore(prop_dictionary_t, npf_session_t *);
300 
301 /* ALG interface. */
302 void		npf_alg_sysinit(void);
303 void		npf_alg_sysfini(void);
304 npf_alg_t *	npf_alg_register(npf_alg_func_t, npf_alg_func_t,
305 		    npf_alg_sfunc_t);
306 int		npf_alg_unregister(npf_alg_t *);
307 bool		npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
308 void		npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
309 npf_session_t *	npf_alg_session(npf_cache_t *, nbuf_t *, int);
310 
311 /* Debugging routines. */
312 void		npf_addr_dump(const npf_addr_t *);
313 void		npf_rulenc_dump(const npf_rule_t *);
314 void		npf_sessions_dump(void);
315 void		npf_state_dump(const npf_state_t *);
316 void		npf_nat_dump(const npf_nat_t *);
317 void		npf_state_setsampler(void (*)(npf_state_t *, bool));
318 
319 #endif	/* _NPF_IMPL_H_ */
320