1 /* $NetBSD: npf_impl.h,v 1.11 2012/02/20 00:18:19 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) && !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 #define NPF_DECISION_BLOCK 0 95 #define NPF_DECISION_PASS 1 96 97 typedef bool (*npf_algfunc_t)(npf_cache_t *, nbuf_t *, void *); 98 99 #define NPF_NCODE_LIMIT 1024 100 #define NPF_TABLE_SLOTS 32 101 102 /* 103 * SESSION STATE STRUCTURES 104 */ 105 106 #define NPF_FLOW_FORW 0 107 #define NPF_FLOW_BACK 1 108 109 typedef struct { 110 uint32_t nst_end; 111 uint32_t nst_maxend; 112 uint32_t nst_maxwin; 113 int nst_wscale; 114 } npf_tcpstate_t; 115 116 typedef struct { 117 kmutex_t nst_lock; 118 int nst_state; 119 npf_tcpstate_t nst_tcpst[2]; 120 } npf_state_t; 121 122 /* 123 * INTERFACES. 124 */ 125 126 /* NPF control, statistics, etc. */ 127 void npf_core_enter(void); 128 npf_ruleset_t * npf_core_ruleset(void); 129 npf_ruleset_t * npf_core_natset(void); 130 npf_tableset_t *npf_core_tableset(void); 131 void npf_core_exit(void); 132 bool npf_core_locked(void); 133 bool npf_default_pass(void); 134 void npf_reload(npf_ruleset_t *, npf_tableset_t *, 135 npf_ruleset_t *, bool); 136 137 void npflogattach(int); 138 void npflogdetach(void); 139 int npfctl_switch(void *); 140 int npfctl_reload(u_long, void *); 141 int npfctl_sessions_save(u_long, void *); 142 int npfctl_sessions_load(u_long, void *); 143 int npfctl_update_rule(u_long, void *); 144 int npfctl_table(void *); 145 146 void npf_stats_inc(npf_stats_t); 147 void npf_stats_dec(npf_stats_t); 148 149 /* Packet filter hooks. */ 150 int npf_register_pfil(void); 151 void npf_unregister_pfil(void); 152 void npf_log_packet(npf_cache_t *, nbuf_t *, int); 153 154 /* Protocol helpers. */ 155 bool npf_fetch_ip(npf_cache_t *, nbuf_t *, void *); 156 bool npf_fetch_tcp(npf_cache_t *, nbuf_t *, void *); 157 bool npf_fetch_udp(npf_cache_t *, nbuf_t *, void *); 158 bool npf_fetch_icmp(npf_cache_t *, nbuf_t *, void *); 159 int npf_cache_all(npf_cache_t *, nbuf_t *); 160 161 bool npf_rwrip(npf_cache_t *, nbuf_t *, void *, const int, 162 npf_addr_t *); 163 bool npf_rwrport(npf_cache_t *, nbuf_t *, void *, const int, 164 in_port_t); 165 bool npf_rwrcksum(npf_cache_t *, nbuf_t *, void *, const int, 166 npf_addr_t *, in_port_t); 167 168 uint16_t npf_fixup16_cksum(uint16_t, uint16_t, uint16_t); 169 uint16_t npf_fixup32_cksum(uint16_t, uint32_t, uint32_t); 170 uint16_t npf_addr_cksum(uint16_t, int, npf_addr_t *, npf_addr_t *); 171 uint32_t npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *); 172 int npf_tcpsaw(npf_cache_t *, tcp_seq *, tcp_seq *, uint32_t *); 173 bool npf_fetch_tcpopts(const npf_cache_t *, nbuf_t *, 174 uint16_t *, int *); 175 bool npf_normalize(npf_cache_t *, nbuf_t *, bool, bool, u_int, u_int); 176 void npf_return_block(npf_cache_t *, nbuf_t *, const int); 177 178 /* Complex instructions. */ 179 int npf_match_ether(nbuf_t *, int, int, uint16_t, uint32_t *); 180 int npf_match_table(npf_cache_t *, nbuf_t *, void *, 181 const int, const u_int); 182 int npf_match_ipmask(npf_cache_t *, nbuf_t *, void *, 183 const int, const npf_addr_t *, const npf_netmask_t); 184 int npf_match_tcp_ports(npf_cache_t *, nbuf_t *, void *, 185 const int, const uint32_t); 186 int npf_match_udp_ports(npf_cache_t *, nbuf_t *, void *, 187 const int, const uint32_t); 188 int npf_match_icmp4(npf_cache_t *, nbuf_t *, void *, uint32_t); 189 int npf_match_tcpfl(npf_cache_t *, nbuf_t *, void *, uint32_t); 190 191 /* Tableset interface. */ 192 void npf_tableset_sysinit(void); 193 void npf_tableset_sysfini(void); 194 195 npf_tableset_t *npf_tableset_create(void); 196 void npf_tableset_destroy(npf_tableset_t *); 197 int npf_tableset_insert(npf_tableset_t *, npf_table_t *); 198 npf_tableset_t *npf_tableset_reload(npf_tableset_t *); 199 200 npf_table_t * npf_table_create(u_int, int, size_t); 201 void npf_table_destroy(npf_table_t *); 202 void npf_table_ref(npf_table_t *); 203 void npf_table_unref(npf_table_t *); 204 205 npf_table_t * npf_table_get(npf_tableset_t *, u_int); 206 void npf_table_put(npf_table_t *); 207 int npf_table_check(npf_tableset_t *, u_int, int); 208 int npf_table_add_cidr(npf_tableset_t *, u_int, 209 const npf_addr_t *, const npf_netmask_t); 210 int npf_table_rem_cidr(npf_tableset_t *, u_int, 211 const npf_addr_t *, const npf_netmask_t); 212 int npf_table_match_addr(npf_tableset_t *, u_int, 213 const npf_addr_t *); 214 215 /* Ruleset interface. */ 216 npf_ruleset_t * npf_ruleset_create(void); 217 void npf_ruleset_destroy(npf_ruleset_t *); 218 void npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *); 219 void npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *); 220 npf_rule_t * npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *); 221 npf_rule_t * npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *); 222 npf_rule_t * npf_ruleset_replace(const char *, npf_ruleset_t *); 223 224 npf_rule_t * npf_ruleset_inspect(npf_cache_t *, nbuf_t *, npf_ruleset_t *, 225 ifnet_t *, const int, const int); 226 int npf_rule_apply(npf_cache_t *, nbuf_t *, npf_rule_t *, int *); 227 228 /* Rule interface. */ 229 npf_rule_t * npf_rule_alloc(prop_dictionary_t, npf_rproc_t *, void *, size_t); 230 void npf_rule_free(npf_rule_t *); 231 npf_ruleset_t * npf_rule_subset(npf_rule_t *); 232 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *); 233 void npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *); 234 npf_rproc_t * npf_rule_getrproc(npf_rule_t *); 235 236 npf_rproc_t * npf_rproc_create(prop_dictionary_t); 237 void npf_rproc_acquire(npf_rproc_t *); 238 void npf_rproc_release(npf_rproc_t *); 239 void npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int); 240 241 /* Session handling interface. */ 242 void npf_session_sysinit(void); 243 void npf_session_sysfini(void); 244 int npf_session_tracking(bool); 245 246 npf_sehash_t * sess_htable_create(void); 247 void sess_htable_destroy(npf_sehash_t *); 248 void sess_htable_reload(npf_sehash_t *); 249 250 npf_session_t * npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *); 251 npf_session_t * npf_session_establish(const npf_cache_t *, nbuf_t *, const int); 252 void npf_session_release(npf_session_t *); 253 void npf_session_expire(npf_session_t *); 254 bool npf_session_pass(const npf_session_t *, npf_rproc_t **); 255 void npf_session_setpass(npf_session_t *, npf_rproc_t *); 256 int npf_session_setnat(npf_session_t *, npf_nat_t *, const int); 257 npf_nat_t * npf_session_retnat(npf_session_t *, const int, bool *); 258 259 int npf_session_save(prop_array_t, prop_array_t); 260 int npf_session_restore(npf_sehash_t *, prop_dictionary_t); 261 262 /* State handling. */ 263 bool npf_state_init(const npf_cache_t *, nbuf_t *, npf_state_t *); 264 bool npf_state_inspect(const npf_cache_t *, nbuf_t *, npf_state_t *, 265 const bool); 266 int npf_state_etime(const npf_state_t *, const int); 267 void npf_state_destroy(npf_state_t *); 268 269 bool npf_state_tcp(const npf_cache_t *, nbuf_t *, npf_state_t *, int); 270 int npf_state_tcp_timeout(const npf_state_t *); 271 272 /* NAT. */ 273 void npf_nat_sysinit(void); 274 void npf_nat_sysfini(void); 275 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *); 276 void npf_nat_freepolicy(npf_natpolicy_t *); 277 bool npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *); 278 bool npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *); 279 280 int npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, 281 ifnet_t *, const int); 282 void npf_nat_expire(npf_nat_t *); 283 void npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *); 284 void npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *); 285 void npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t); 286 287 int npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *); 288 npf_nat_t * npf_nat_restore(prop_dictionary_t, npf_session_t *); 289 290 /* ALG interface. */ 291 void npf_alg_sysinit(void); 292 void npf_alg_sysfini(void); 293 npf_alg_t * npf_alg_register(npf_algfunc_t, npf_algfunc_t, 294 npf_algfunc_t, npf_algfunc_t); 295 int npf_alg_unregister(npf_alg_t *); 296 bool npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *); 297 void npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, const int ); 298 bool npf_alg_sessionid(npf_cache_t *, nbuf_t *, npf_cache_t *); 299 300 /* Debugging routines. */ 301 void npf_rulenc_dump(npf_rule_t *); 302 void npf_sessions_dump(void); 303 void npf_state_dump(npf_state_t *); 304 void npf_nat_dump(npf_nat_t *); 305 306 #endif /* _NPF_IMPL_H_ */ 307