1 /* $NetBSD: npf_impl.h,v 1.29 2013/03/20 00:29:47 christos Exp $ */ 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 71 struct npf_ruleset; 72 struct npf_rule; 73 struct npf_rprocset; 74 struct npf_nat; 75 struct npf_session; 76 77 typedef struct npf_ruleset npf_ruleset_t; 78 typedef struct npf_rule npf_rule_t; 79 typedef struct npf_nat npf_nat_t; 80 typedef struct npf_rprocset npf_rprocset_t; 81 typedef struct npf_alg npf_alg_t; 82 typedef struct npf_natpolicy npf_natpolicy_t; 83 typedef struct npf_session npf_session_t; 84 85 struct npf_sehash; 86 struct npf_table; 87 88 typedef struct npf_sehash npf_sehash_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 typedef bool (*npf_alg_func_t)(npf_cache_t *, nbuf_t *, npf_nat_t *, int); 98 typedef 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 1 109 110 typedef struct { 111 uint32_t nst_end; 112 uint32_t nst_maxend; 113 uint32_t nst_maxwin; 114 int nst_wscale; 115 } npf_tcpstate_t; 116 117 typedef 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. */ 128 void npf_config_init(void); 129 void npf_config_fini(void); 130 131 void npf_config_enter(void); 132 void npf_config_exit(void); 133 void npf_config_sync(void); 134 bool npf_config_locked_p(void); 135 int npf_config_read_enter(void); 136 void npf_config_read_exit(int); 137 138 void npf_config_reload(prop_dictionary_t, npf_ruleset_t *, 139 npf_tableset_t *, npf_ruleset_t *, npf_rprocset_t *, bool); 140 npf_ruleset_t * npf_config_ruleset(void); 141 npf_ruleset_t * npf_config_natset(void); 142 npf_tableset_t *npf_config_tableset(void); 143 prop_dictionary_t npf_config_dict(void); 144 bool npf_default_pass(void); 145 146 void npflogattach(int); 147 void npflogdetach(void); 148 int npfctl_switch(void *); 149 int npfctl_reload(u_long, void *); 150 int npfctl_getconf(u_long, void *); 151 int npfctl_sessions_save(u_long, void *); 152 int npfctl_sessions_load(u_long, void *); 153 int npfctl_rule(u_long, void *); 154 int npfctl_table(void *); 155 156 void npf_stats_inc(npf_stats_t); 157 void npf_stats_dec(npf_stats_t); 158 159 /* Packet filter hooks. */ 160 int npf_pfil_register(void); 161 void npf_pfil_unregister(void); 162 bool npf_pfil_registered_p(void); 163 int npf_packet_handler(void *, struct mbuf **, ifnet_t *, int); 164 165 /* Protocol helpers. */ 166 int npf_cache_all(npf_cache_t *, nbuf_t *); 167 void npf_recache(npf_cache_t *, nbuf_t *); 168 169 bool npf_rwrip(const npf_cache_t *, int, const npf_addr_t *); 170 bool npf_rwrport(const npf_cache_t *, int, const in_port_t); 171 bool npf_rwrcksum(const npf_cache_t *, const int, 172 const npf_addr_t *, const in_port_t); 173 174 uint16_t npf_fixup16_cksum(uint16_t, uint16_t, uint16_t); 175 uint16_t npf_fixup32_cksum(uint16_t, uint32_t, uint32_t); 176 uint16_t npf_addr_cksum(uint16_t, int, const npf_addr_t *, 177 const npf_addr_t *); 178 uint32_t npf_addr_sum(const int, const npf_addr_t *, const npf_addr_t *); 179 int npf_addr_cmp(const npf_addr_t *, const npf_netmask_t, 180 const npf_addr_t *, const npf_netmask_t, const int); 181 void npf_addr_mask(const npf_addr_t *, const npf_netmask_t, 182 const int, npf_addr_t *); 183 184 int npf_tcpsaw(const npf_cache_t *, tcp_seq *, tcp_seq *, 185 uint32_t *); 186 bool npf_fetch_tcpopts(npf_cache_t *, nbuf_t *, uint16_t *, int *); 187 bool npf_return_block(npf_cache_t *, nbuf_t *, const int); 188 189 /* Complex instructions. */ 190 int npf_match_ether(nbuf_t *, int, uint16_t, uint32_t *); 191 int npf_match_proto(const npf_cache_t *, uint32_t); 192 int npf_match_table(const npf_cache_t *, int, u_int); 193 int npf_match_ipmask(const npf_cache_t *, int, 194 const npf_addr_t *, npf_netmask_t); 195 int npf_match_tcp_ports(const npf_cache_t *, int, uint32_t); 196 int npf_match_udp_ports(const npf_cache_t *, int, uint32_t); 197 int npf_match_icmp4(const npf_cache_t *, uint32_t); 198 int npf_match_icmp6(const npf_cache_t *, uint32_t); 199 int npf_match_tcpfl(const npf_cache_t *, uint32_t); 200 201 /* Tableset interface. */ 202 void npf_tableset_sysinit(void); 203 void npf_tableset_sysfini(void); 204 205 extern const pt_tree_ops_t npf_table_ptree_ops; 206 207 npf_tableset_t *npf_tableset_create(void); 208 void npf_tableset_destroy(npf_tableset_t *); 209 int npf_tableset_insert(npf_tableset_t *, npf_table_t *); 210 void npf_tableset_reload(npf_tableset_t *, npf_tableset_t *); 211 212 npf_table_t * npf_table_create(u_int, int, size_t); 213 void npf_table_destroy(npf_table_t *); 214 215 int npf_table_check(const npf_tableset_t *, u_int, int); 216 int npf_table_insert(npf_tableset_t *, u_int, 217 const int, const npf_addr_t *, const npf_netmask_t); 218 int npf_table_remove(npf_tableset_t *, u_int, 219 const int, const npf_addr_t *, const npf_netmask_t); 220 int npf_table_lookup(npf_tableset_t *, u_int, 221 const int, const npf_addr_t *); 222 int npf_table_list(npf_tableset_t *, u_int, void *, size_t); 223 224 /* Ruleset interface. */ 225 npf_ruleset_t * npf_ruleset_create(size_t); 226 void npf_ruleset_destroy(npf_ruleset_t *); 227 void npf_ruleset_insert(npf_ruleset_t *, npf_rule_t *); 228 void npf_ruleset_reload(npf_ruleset_t *, npf_ruleset_t *); 229 void npf_ruleset_natreload(npf_ruleset_t *, npf_ruleset_t *); 230 npf_rule_t * npf_ruleset_matchnat(npf_ruleset_t *, npf_natpolicy_t *); 231 npf_rule_t * npf_ruleset_sharepm(npf_ruleset_t *, npf_natpolicy_t *); 232 void npf_ruleset_freealg(npf_ruleset_t *, npf_alg_t *); 233 234 int npf_ruleset_add(npf_ruleset_t *, const char *, npf_rule_t *); 235 int npf_ruleset_remove(npf_ruleset_t *, const char *, uint64_t); 236 int npf_ruleset_remkey(npf_ruleset_t *, const char *, 237 const void *, size_t); 238 prop_dictionary_t npf_ruleset_list(npf_ruleset_t *, const char *); 239 int npf_ruleset_flush(npf_ruleset_t *, const char *); 240 void npf_ruleset_gc(npf_ruleset_t *); 241 242 npf_rule_t * npf_ruleset_inspect(npf_cache_t *, nbuf_t *, 243 const npf_ruleset_t *, const int, const int); 244 int npf_rule_conclude(const npf_rule_t *, int *); 245 246 /* Rule interface. */ 247 npf_rule_t * npf_rule_alloc(prop_dictionary_t); 248 void npf_rule_setcode(npf_rule_t *, int, void *, size_t); 249 void npf_rule_setrproc(npf_rule_t *, npf_rproc_t *); 250 void npf_rule_free(npf_rule_t *); 251 uint64_t npf_rule_getid(const npf_rule_t *); 252 npf_natpolicy_t *npf_rule_getnat(const npf_rule_t *); 253 void npf_rule_setnat(npf_rule_t *, npf_natpolicy_t *); 254 npf_rproc_t * npf_rule_getrproc(npf_rule_t *); 255 256 void npf_ext_sysinit(void); 257 void npf_ext_sysfini(void); 258 int npf_ext_construct(const char *, 259 npf_rproc_t *, prop_dictionary_t); 260 261 npf_rprocset_t *npf_rprocset_create(void); 262 void npf_rprocset_destroy(npf_rprocset_t *); 263 npf_rproc_t * npf_rprocset_lookup(npf_rprocset_t *, const char *); 264 void npf_rprocset_insert(npf_rprocset_t *, npf_rproc_t *); 265 266 npf_rproc_t * npf_rproc_create(prop_dictionary_t); 267 void npf_rproc_acquire(npf_rproc_t *); 268 void npf_rproc_release(npf_rproc_t *); 269 void npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int *); 270 271 /* Session handling interface. */ 272 void npf_session_sysinit(void); 273 void npf_session_sysfini(void); 274 int npf_session_tracking(bool); 275 276 npf_sehash_t * sess_htable_create(void); 277 void sess_htable_destroy(npf_sehash_t *); 278 void sess_htable_reload(npf_sehash_t *); 279 280 npf_session_t * npf_session_lookup(const npf_cache_t *, const nbuf_t *, 281 const int, bool *); 282 npf_session_t * npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *); 283 npf_session_t * npf_session_establish(npf_cache_t *, nbuf_t *, const int); 284 void npf_session_release(npf_session_t *); 285 void npf_session_expire(npf_session_t *); 286 bool npf_session_pass(const npf_session_t *, npf_rproc_t **); 287 void npf_session_setpass(npf_session_t *, npf_rproc_t *); 288 int npf_session_setnat(npf_session_t *, npf_nat_t *, const int); 289 npf_nat_t * npf_session_retnat(npf_session_t *, const int, bool *); 290 291 int npf_session_save(prop_array_t, prop_array_t); 292 int npf_session_restore(npf_sehash_t *, prop_dictionary_t); 293 294 /* State handling. */ 295 bool npf_state_init(npf_cache_t *, nbuf_t *, npf_state_t *); 296 bool npf_state_inspect(npf_cache_t *, nbuf_t *, npf_state_t *, 297 const bool); 298 int npf_state_etime(const npf_state_t *, const int); 299 void npf_state_destroy(npf_state_t *); 300 301 bool npf_state_tcp(npf_cache_t *, nbuf_t *, npf_state_t *, int); 302 int npf_state_tcp_timeout(const npf_state_t *); 303 304 /* NAT. */ 305 void npf_nat_sysinit(void); 306 void npf_nat_sysfini(void); 307 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *); 308 void npf_nat_freepolicy(npf_natpolicy_t *); 309 bool npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *); 310 bool npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *); 311 void npf_nat_freealg(npf_natpolicy_t *, npf_alg_t *); 312 313 int npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, const int); 314 int npf_nat_translate(npf_cache_t *, nbuf_t *, npf_nat_t *, 315 const bool, const int); 316 void npf_nat_expire(npf_nat_t *); 317 void npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *); 318 void npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *); 319 void npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t); 320 321 int npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *); 322 npf_nat_t * npf_nat_restore(prop_dictionary_t, npf_session_t *); 323 324 /* ALG interface. */ 325 void npf_alg_sysinit(void); 326 void npf_alg_sysfini(void); 327 npf_alg_t * npf_alg_register(const char *, npf_alg_func_t, npf_alg_func_t, 328 npf_alg_sfunc_t); 329 int npf_alg_unregister(npf_alg_t *); 330 npf_alg_t * npf_alg_construct(const char *); 331 bool npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *, int); 332 void npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, int); 333 npf_session_t * npf_alg_session(npf_cache_t *, nbuf_t *, int); 334 335 /* Debugging routines. */ 336 void npf_addr_dump(const npf_addr_t *); 337 void npf_rulenc_dump(const npf_rule_t *); 338 void npf_sessions_dump(void); 339 void npf_state_dump(const npf_state_t *); 340 void npf_nat_dump(const npf_nat_t *); 341 void npf_state_setsampler(void (*)(npf_state_t *, bool)); 342 343 #endif /* _NPF_IMPL_H_ */ 344