1 /* $NetBSD: npf_impl.h,v 1.9 2011/11/29 20:05:30 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 *); 229 230 npf_rproc_t * npf_rproc_create(prop_dictionary_t); 231 npf_rproc_t * npf_rproc_return(npf_rule_t *); 232 void npf_rproc_release(npf_rproc_t *); 233 void npf_rproc_run(npf_cache_t *, nbuf_t *, npf_rproc_t *, int); 234 235 /* Session handling interface. */ 236 void npf_session_sysinit(void); 237 void npf_session_sysfini(void); 238 int npf_session_tracking(bool); 239 240 npf_sehash_t * sess_htable_create(void); 241 void sess_htable_destroy(npf_sehash_t *); 242 void sess_htable_reload(npf_sehash_t *); 243 244 npf_session_t * npf_session_inspect(npf_cache_t *, nbuf_t *, const int, int *); 245 npf_session_t * npf_session_establish(const npf_cache_t *, nbuf_t *, const int); 246 void npf_session_release(npf_session_t *); 247 void npf_session_expire(npf_session_t *); 248 bool npf_session_pass(const npf_session_t *, npf_rproc_t **); 249 void npf_session_setpass(npf_session_t *, npf_rproc_t *); 250 int npf_session_setnat(npf_session_t *, npf_nat_t *, const int); 251 npf_nat_t * npf_session_retnat(npf_session_t *, const int, bool *); 252 253 int npf_session_save(prop_array_t, prop_array_t); 254 int npf_session_restore(npf_sehash_t *, prop_dictionary_t); 255 256 /* State handling. */ 257 bool npf_state_init(const npf_cache_t *, nbuf_t *, npf_state_t *); 258 bool npf_state_inspect(const npf_cache_t *, nbuf_t *, npf_state_t *, 259 const bool); 260 int npf_state_etime(const npf_state_t *, const int); 261 void npf_state_destroy(npf_state_t *); 262 263 bool npf_state_tcp(const npf_cache_t *, nbuf_t *, npf_state_t *, int); 264 int npf_state_tcp_timeout(const npf_state_t *); 265 266 /* NAT. */ 267 void npf_nat_sysinit(void); 268 void npf_nat_sysfini(void); 269 npf_natpolicy_t *npf_nat_newpolicy(prop_dictionary_t, npf_ruleset_t *); 270 void npf_nat_freepolicy(npf_natpolicy_t *); 271 bool npf_nat_matchpolicy(npf_natpolicy_t *, npf_natpolicy_t *); 272 bool npf_nat_sharepm(npf_natpolicy_t *, npf_natpolicy_t *); 273 274 int npf_do_nat(npf_cache_t *, npf_session_t *, nbuf_t *, 275 ifnet_t *, const int); 276 void npf_nat_expire(npf_nat_t *); 277 void npf_nat_getorig(npf_nat_t *, npf_addr_t **, in_port_t *); 278 void npf_nat_gettrans(npf_nat_t *, npf_addr_t **, in_port_t *); 279 void npf_nat_setalg(npf_nat_t *, npf_alg_t *, uintptr_t); 280 281 int npf_nat_save(prop_dictionary_t, prop_array_t, npf_nat_t *); 282 npf_nat_t * npf_nat_restore(prop_dictionary_t, npf_session_t *); 283 284 /* ALG interface. */ 285 void npf_alg_sysinit(void); 286 void npf_alg_sysfini(void); 287 npf_alg_t * npf_alg_register(npf_algfunc_t, npf_algfunc_t, 288 npf_algfunc_t, npf_algfunc_t); 289 int npf_alg_unregister(npf_alg_t *); 290 bool npf_alg_match(npf_cache_t *, nbuf_t *, npf_nat_t *); 291 void npf_alg_exec(npf_cache_t *, nbuf_t *, npf_nat_t *, const int ); 292 bool npf_alg_sessionid(npf_cache_t *, nbuf_t *, npf_cache_t *); 293 294 /* Debugging routines. */ 295 void npf_rulenc_dump(npf_rule_t *); 296 void npf_sessions_dump(void); 297 void npf_state_dump(npf_state_t *); 298 void npf_nat_dump(npf_nat_t *); 299 300 #endif /* _NPF_IMPL_H_ */ 301