1/*	$NetBSD$	*/
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
71struct npf_ruleset;
72struct npf_rule;
73struct npf_rprocset;
74struct npf_nat;
75struct npf_session;
76
77typedef struct npf_ruleset	npf_ruleset_t;
78typedef struct npf_rule		npf_rule_t;
79typedef struct npf_nat		npf_nat_t;
80typedef struct npf_rprocset	npf_rprocset_t;
81typedef struct npf_alg		npf_alg_t;
82typedef struct npf_natpolicy	npf_natpolicy_t;
83typedef struct npf_session	npf_session_t;
84
85struct npf_sehash;
86struct npf_table;
87
88typedef struct npf_sehash	npf_sehash_t;
89typedef struct npf_table	npf_table_t;
90
91typedef npf_table_t *		npf_tableset_t;
92
93/*
94 * DEFINITIONS.
95 */
96
97typedef bool (*npf_alg_func_t)(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
98typedef 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
110typedef 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
117typedef 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. */
128void		npf_config_init(void);
129void		npf_config_fini(void);
130
131void		npf_config_enter(void);
132void		npf_config_exit(void);
133void		npf_config_sync(void);
134bool		npf_config_locked_p(void);
135int		npf_config_read_enter(void);
136void		npf_config_read_exit(int);
137
138void		npf_config_reload(prop_dictionary_t, npf_ruleset_t *,
139		    npf_tableset_t *, npf_ruleset_t *, npf_rprocset_t *, bool);
140npf_ruleset_t *	npf_config_ruleset(void);
141npf_ruleset_t *	npf_config_natset(void);
142npf_tableset_t *npf_config_tableset(void);
143prop_dictionary_t npf_config_dict(void);
144bool		npf_default_pass(void);
145
146void		npflogattach(int);
147void		npflogdetach(void);
148int		npfctl_switch(void *);
149int		npfctl_reload(u_long, void *);
150int		npfctl_getconf(u_long, void *);
151int		npfctl_sessions_save(u_long, void *);
152int		npfctl_sessions_load(u_long, void *);
153int		npfctl_rule(u_long, void *);
154int		npfctl_table(void *);
155
156void		npf_stats_inc(npf_stats_t);
157void		npf_stats_dec(npf_stats_t);
158
159/* Packet filter hooks. */
160int		npf_pfil_register(void);
161void		npf_pfil_unregister(void);
162bool		npf_pfil_registered_p(void);
163int		npf_packet_handler(void *, struct mbuf **, ifnet_t *, int);
164
165/* Protocol helpers. */
166int		npf_cache_all(npf_cache_t *, nbuf_t *);
167void		npf_recache(npf_cache_t *, nbuf_t *);
168
169bool		npf_rwrip(const npf_cache_t *, int, const npf_addr_t *);
170bool		npf_rwrport(const npf_cache_t *, int, const in_port_t);
171bool		npf_rwrcksum(const npf_cache_t *, const int,
172		    const npf_addr_t *, const in_port_t);
173
174uint16_t	npf_fixup16_cksum(uint16_t, uint16_t, uint16_t);
175uint16_t	npf_fixup32_cksum(uint16_t, uint32_t, uint32_t);
176uint16_t	npf_addr_cksum(uint16_t, int, const npf_addr_t *,
177		    const npf_addr_t *);
178uint32_t	npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *);
179int		npf_addr_cmp(const npf_addr_t *, const npf_netmask_t,
180		    const npf_addr_t *, const npf_netmask_t, const int);
181void		npf_addr_mask(const npf_addr_t *, const npf_netmask_t,
182		    const int, npf_addr_t *);
183
184int		npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *,
185		    uint32_t *);
186bool		npf_fetch_tcpopts(npf_cache_t *, nbuf_t *, uint16_t *, int *);
187bool		npf_return_block(npf_cache_t *, nbuf_t *, const int);
188
189/* Complex instructions. */
190int		npf_match_ether(nbuf_t *, int, uint16_t, uint32_t *);
191int		npf_match_proto(const npf_cache_t *, uint32_t);
192int		npf_match_table(const npf_cache_t *, int, u_int);
193int		npf_match_ipmask(const npf_cache_t *, int,
194		    const npf_addr_t *, npf_netmask_t);
195int		npf_match_tcp_ports(const npf_cache_t *, int, uint32_t);
196int		npf_match_udp_ports(const npf_cache_t *, int, uint32_t);
197int		npf_match_icmp4(const npf_cache_t *, uint32_t);
198int		npf_match_icmp6(const npf_cache_t *, uint32_t);
199int		npf_match_tcpfl(const npf_cache_t *, uint32_t);
200
201/* Tableset interface. */
202void		npf_tableset_sysinit(void);
203void		npf_tableset_sysfini(void);
204
205extern const pt_tree_ops_t npf_table_ptree_ops;
206
207npf_tableset_t *npf_tableset_create(void);
208void		npf_tableset_destroy(npf_tableset_t *);
209int		npf_tableset_insert(npf_tableset_t *, npf_table_t *);
210void		npf_tableset_reload(npf_tableset_t *, npf_tableset_t *);
211
212npf_table_t *	npf_table_create(u_int, int, size_t);
213void		npf_table_destroy(npf_table_t *);
214
215int		npf_table_check(const npf_tableset_t *, u_int, int);
216int		npf_table_insert(npf_tableset_t *, u_int,
217		    const int, const npf_addr_t *, const npf_netmask_t);
218int		npf_table_remove(npf_tableset_t *, u_int,
219		    const int, const npf_addr_t *, const npf_netmask_t);
220int		npf_table_lookup(npf_tableset_t *, u_int,
221		    const int, const npf_addr_t *);
222int		npf_table_list(npf_tableset_t *, u_int, void *, size_t);
223
224/* Ruleset interface. */
225npf_ruleset_t *	npf_ruleset_create(size_t);
226void		npf_ruleset_destroy(npf_ruleset_t *);
227void		npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *);
228void		npf_ruleset_reload(npf_ruleset_t *, npf_ruleset_t *);
229void		npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *);
230npf_rule_t *	npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *);
231npf_rule_t *	npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *);
232void		npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *);
233
234int		npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *);
235int		npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t);
236int		npf_ruleset_remkey(npf_ruleset_t *, const char *,
237		    const void *, size_t);
238prop_dictionary_t npf_ruleset_list(npf_ruleset_t *, const char *);
239int		npf_ruleset_flush(npf_ruleset_t *, const char *);
240void		npf_ruleset_gc(npf_ruleset_t *);
241
242npf_rule_t *	npf_ruleset_inspect(npf_cache_t *, nbuf_t *,
243		    const npf_ruleset_t *, const int, const int);
244int		npf_rule_conclude(const npf_rule_t *, int *);
245
246/* Rule interface. */
247npf_rule_t *	npf_rule_alloc(prop_dictionary_t);
248void		npf_rule_setcode(npf_rule_t *, int, void *, size_t);
249void		npf_rule_setrproc(npf_rule_t *, npf_rproc_t *);
250void		npf_rule_free(npf_rule_t *);
251uint64_t	npf_rule_getid(const npf_rule_t *);
252npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *);
253void		npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *);
254npf_rproc_t *	npf_rule_getrproc(npf_rule_t *);
255
256void		npf_ext_sysinit(void);
257void		npf_ext_sysfini(void);
258int		npf_ext_construct(const char *,
259		    npf_rproc_t *, prop_dictionary_t);
260
261npf_rprocset_t *npf_rprocset_create(void);
262void		npf_rprocset_destroy(npf_rprocset_t *);
263npf_rproc_t *	npf_rprocset_lookup(npf_rprocset_t *, const char *);
264void		npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *);
265
266npf_rproc_t *	npf_rproc_create(prop_dictionary_t);
267void		npf_rproc_acquire(npf_rproc_t *);
268void		npf_rproc_release(npf_rproc_t *);
269void		npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int *);
270
271/* Session handling interface. */
272void		npf_session_sysinit(void);
273void		npf_session_sysfini(void);
274int		npf_session_tracking(bool);
275
276npf_sehash_t *	sess_htable_create(void);
277void		sess_htable_destroy(npf_sehash_t *);
278void		sess_htable_reload(npf_sehash_t *);
279
280npf_session_t *	npf_session_lookup(const npf_cache_t *, const nbuf_t *,
281		    const int, bool *);
282npf_session_t *	npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *);
283npf_session_t *	npf_session_establish(npf_cache_t *, nbuf_t *, const int);
284void		npf_session_release(npf_session_t *);
285void		npf_session_expire(npf_session_t *);
286bool		npf_session_pass(const npf_session_t *, npf_rproc_t **);
287void		npf_session_setpass(npf_session_t *, npf_rproc_t *);
288int		npf_session_setnat(npf_session_t *, npf_nat_t *, u_int);
289npf_nat_t *	npf_session_retnat(npf_session_t *, const int, bool *);
290
291int		npf_session_save(prop_array_t, prop_array_t);
292int		npf_session_restore(npf_sehash_t *, prop_dictionary_t);
293
294/* State handling. */
295bool		npf_state_init(npf_cache_t *, nbuf_t *, npf_state_t *);
296bool		npf_state_inspect(npf_cache_t *, nbuf_t *, npf_state_t *,
297		    const bool);
298int		npf_state_etime(const npf_state_t *, const int);
299void		npf_state_destroy(npf_state_t *);
300
301bool		npf_state_tcp(npf_cache_t *, nbuf_t *, npf_state_t *, int);
302int		npf_state_tcp_timeout(const npf_state_t *);
303
304/* NAT. */
305void		npf_nat_sysinit(void);
306void		npf_nat_sysfini(void);
307npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *);
308void		npf_nat_freepolicy(npf_natpolicy_t *);
309bool		npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *);
310bool		npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *);
311void		npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *);
312
313int		npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, const int);
314int		npf_nat_translate(npf_cache_t *, nbuf_t *, npf_nat_t *,
315		    const bool, const int);
316void		npf_nat_expire(npf_nat_t *);
317void		npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *);
318void		npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *);
319void		npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t);
320
321int		npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *);
322npf_nat_t *	npf_nat_restore(prop_dictionary_t, npf_session_t *);
323
324/* ALG interface. */
325void		npf_alg_sysinit(void);
326void		npf_alg_sysfini(void);
327npf_alg_t *	npf_alg_register(npf_alg_func_t, npf_alg_func_t,
328		    npf_alg_sfunc_t);
329int		npf_alg_unregister(npf_alg_t *);
330bool		npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
331void		npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, int);
332npf_session_t *	npf_alg_session(npf_cache_t *, nbuf_t *, int);
333
334/* Debugging routines. */
335void		npf_addr_dump(const npf_addr_t *);
336void		npf_rulenc_dump(const npf_rule_t *);
337void		npf_sessions_dump(void);
338void		npf_state_dump(const npf_state_t *);
339void		npf_nat_dump(const npf_nat_t *);
340void		npf_state_setsampler(void (*)(npf_state_t *, bool));
341
342#endif	/* _NPF_IMPL_H_ */
343