1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2017-2018 Yandex LLC 5 * Copyright (c) 2017-2018 Andrey V. Elsukov <ae@FreeBSD.org> 6 * Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_ipfw.h" 36 #ifndef INET 37 #error IPFIREWALL requires INET. 38 #endif /* INET */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/hash.h> 43 #include <sys/mbuf.h> 44 #include <sys/kernel.h> 45 #include <sys/lock.h> 46 #include <sys/pcpu.h> 47 #include <sys/queue.h> 48 #include <sys/rmlock.h> 49 #include <sys/smp.h> 50 #include <sys/socket.h> 51 #include <sys/sysctl.h> 52 #include <sys/syslog.h> 53 #include <net/ethernet.h> 54 #include <net/if.h> 55 #include <net/if_var.h> 56 #include <net/pfil.h> 57 #include <net/vnet.h> 58 59 #include <netinet/in.h> 60 #include <netinet/ip.h> 61 #include <netinet/ip_var.h> 62 #include <netinet/ip_fw.h> 63 #include <netinet/tcp_var.h> 64 #include <netinet/udp.h> 65 66 #include <netinet/ip6.h> /* IN6_ARE_ADDR_EQUAL */ 67 #ifdef INET6 68 #include <netinet6/in6_var.h> 69 #include <netinet6/ip6_var.h> 70 #include <netinet6/scope6_var.h> 71 #endif 72 73 #include <netpfil/ipfw/ip_fw_private.h> 74 75 #include <machine/in_cksum.h> /* XXX for in_cksum */ 76 77 #ifdef MAC 78 #include <security/mac/mac_framework.h> 79 #endif 80 81 /* 82 * Description of dynamic states. 83 * 84 * Dynamic states are stored in lists accessed through a hash tables 85 * whose size is curr_dyn_buckets. This value can be modified through 86 * the sysctl variable dyn_buckets. 87 * 88 * Currently there are four tables: dyn_ipv4, dyn_ipv6, dyn_ipv4_parent, 89 * and dyn_ipv6_parent. 90 * 91 * When a packet is received, its address fields hashed, then matched 92 * against the entries in the corresponding list by addr_type. 93 * Dynamic states can be used for different purposes: 94 * + stateful rules; 95 * + enforcing limits on the number of sessions; 96 * + in-kernel NAT (not implemented yet) 97 * 98 * The lifetime of dynamic states is regulated by dyn_*_lifetime, 99 * measured in seconds and depending on the flags. 100 * 101 * The total number of dynamic states is equal to UMA zone items count. 102 * The max number of dynamic states is dyn_max. When we reach 103 * the maximum number of rules we do not create anymore. This is 104 * done to avoid consuming too much memory, but also too much 105 * time when searching on each packet (ideally, we should try instead 106 * to put a limit on the length of the list on each bucket...). 107 * 108 * Each state holds a pointer to the parent ipfw rule so we know what 109 * action to perform. Dynamic rules are removed when the parent rule is 110 * deleted. 111 * 112 * There are some limitations with dynamic rules -- we do not 113 * obey the 'randomized match', and we do not do multiple 114 * passes through the firewall. XXX check the latter!!! 115 */ 116 117 /* By default use jenkins hash function */ 118 #define IPFIREWALL_JENKINSHASH 119 120 #define DYN_COUNTER_INC(d, dir, pktlen) do { \ 121 (d)->pcnt_ ## dir++; \ 122 (d)->bcnt_ ## dir += pktlen; \ 123 } while (0) 124 125 struct dyn_data { 126 void *parent; /* pointer to parent rule */ 127 uint32_t chain_id; /* cached ruleset id */ 128 uint32_t f_pos; /* cached rule index */ 129 130 uint32_t hashval; /* hash value used for hash resize */ 131 uint16_t fibnum; /* fib used to send keepalives */ 132 uint8_t _pad[3]; 133 uint8_t set; /* parent rule set number */ 134 uint16_t rulenum; /* parent rule number */ 135 uint32_t ruleid; /* parent rule id */ 136 137 uint32_t state; /* TCP session state and flags */ 138 uint32_t ack_fwd; /* most recent ACKs in forward */ 139 uint32_t ack_rev; /* and reverse direction (used */ 140 /* to generate keepalives) */ 141 uint32_t sync; /* synchronization time */ 142 uint32_t expire; /* expire time */ 143 144 uint64_t pcnt_fwd; /* bytes counter in forward */ 145 uint64_t bcnt_fwd; /* packets counter in forward */ 146 uint64_t pcnt_rev; /* bytes counter in reverse */ 147 uint64_t bcnt_rev; /* packets counter in reverse */ 148 }; 149 150 #define DPARENT_COUNT_DEC(p) do { \ 151 MPASS(p->count > 0); \ 152 ck_pr_dec_32(&(p)->count); \ 153 } while (0) 154 #define DPARENT_COUNT_INC(p) ck_pr_inc_32(&(p)->count) 155 #define DPARENT_COUNT(p) ck_pr_load_32(&(p)->count) 156 struct dyn_parent { 157 void *parent; /* pointer to parent rule */ 158 uint32_t count; /* number of linked states */ 159 uint8_t _pad; 160 uint8_t set; /* parent rule set number */ 161 uint16_t rulenum; /* parent rule number */ 162 uint32_t ruleid; /* parent rule id */ 163 uint32_t hashval; /* hash value used for hash resize */ 164 uint32_t expire; /* expire time */ 165 }; 166 167 struct dyn_ipv4_state { 168 uint8_t type; /* State type */ 169 uint8_t proto; /* UL Protocol */ 170 uint16_t kidx; /* named object index */ 171 uint16_t sport, dport; /* ULP source and destination ports */ 172 in_addr_t src, dst; /* IPv4 source and destination */ 173 174 union { 175 struct dyn_data *data; 176 struct dyn_parent *limit; 177 }; 178 CK_SLIST_ENTRY(dyn_ipv4_state) entry; 179 SLIST_ENTRY(dyn_ipv4_state) expired; 180 }; 181 CK_SLIST_HEAD(dyn_ipv4ck_slist, dyn_ipv4_state); 182 VNET_DEFINE_STATIC(struct dyn_ipv4ck_slist *, dyn_ipv4); 183 VNET_DEFINE_STATIC(struct dyn_ipv4ck_slist *, dyn_ipv4_parent); 184 185 SLIST_HEAD(dyn_ipv4_slist, dyn_ipv4_state); 186 VNET_DEFINE_STATIC(struct dyn_ipv4_slist, dyn_expired_ipv4); 187 #define V_dyn_ipv4 VNET(dyn_ipv4) 188 #define V_dyn_ipv4_parent VNET(dyn_ipv4_parent) 189 #define V_dyn_expired_ipv4 VNET(dyn_expired_ipv4) 190 191 #ifdef INET6 192 struct dyn_ipv6_state { 193 uint8_t type; /* State type */ 194 uint8_t proto; /* UL Protocol */ 195 uint16_t kidx; /* named object index */ 196 uint16_t sport, dport; /* ULP source and destination ports */ 197 struct in6_addr src, dst; /* IPv6 source and destination */ 198 uint32_t zoneid; /* IPv6 scope zone id */ 199 union { 200 struct dyn_data *data; 201 struct dyn_parent *limit; 202 }; 203 CK_SLIST_ENTRY(dyn_ipv6_state) entry; 204 SLIST_ENTRY(dyn_ipv6_state) expired; 205 }; 206 CK_SLIST_HEAD(dyn_ipv6ck_slist, dyn_ipv6_state); 207 VNET_DEFINE_STATIC(struct dyn_ipv6ck_slist *, dyn_ipv6); 208 VNET_DEFINE_STATIC(struct dyn_ipv6ck_slist *, dyn_ipv6_parent); 209 210 SLIST_HEAD(dyn_ipv6_slist, dyn_ipv6_state); 211 VNET_DEFINE_STATIC(struct dyn_ipv6_slist, dyn_expired_ipv6); 212 #define V_dyn_ipv6 VNET(dyn_ipv6) 213 #define V_dyn_ipv6_parent VNET(dyn_ipv6_parent) 214 #define V_dyn_expired_ipv6 VNET(dyn_expired_ipv6) 215 #endif /* INET6 */ 216 217 /* 218 * Per-CPU pointer indicates that specified state is currently in use 219 * and must not be reclaimed by expiration callout. 220 */ 221 static void **dyn_hp_cache; 222 DPCPU_DEFINE_STATIC(void *, dyn_hp); 223 #define DYNSTATE_GET(cpu) ck_pr_load_ptr(DPCPU_ID_PTR((cpu), dyn_hp)) 224 #define DYNSTATE_PROTECT(v) ck_pr_store_ptr(DPCPU_PTR(dyn_hp), (v)) 225 #define DYNSTATE_RELEASE() DYNSTATE_PROTECT(NULL) 226 #define DYNSTATE_CRITICAL_ENTER() critical_enter() 227 #define DYNSTATE_CRITICAL_EXIT() do { \ 228 DYNSTATE_RELEASE(); \ 229 critical_exit(); \ 230 } while (0); 231 232 /* 233 * We keep two version numbers, one is updated when new entry added to 234 * the list. Second is updated when an entry deleted from the list. 235 * Versions are updated under bucket lock. 236 * 237 * Bucket "add" version number is used to know, that in the time between 238 * state lookup (i.e. ipfw_dyn_lookup_state()) and the followed state 239 * creation (i.e. ipfw_dyn_install_state()) another concurrent thread did 240 * not install some state in this bucket. Using this info we can avoid 241 * additional state lookup, because we are sure that we will not install 242 * the state twice. 243 * 244 * Also doing the tracking of bucket "del" version during lookup we can 245 * be sure, that state entry was not unlinked and freed in time between 246 * we read the state pointer and protect it with hazard pointer. 247 * 248 * An entry unlinked from CK list keeps unchanged until it is freed. 249 * Unlinked entries are linked into expired lists using "expired" field. 250 */ 251 252 /* 253 * dyn_expire_lock is used to protect access to dyn_expired_xxx lists. 254 * dyn_bucket_lock is used to get write access to lists in specific bucket. 255 * Currently one dyn_bucket_lock is used for all ipv4, ipv4_parent, ipv6, 256 * and ipv6_parent lists. 257 */ 258 VNET_DEFINE_STATIC(struct mtx, dyn_expire_lock); 259 VNET_DEFINE_STATIC(struct mtx *, dyn_bucket_lock); 260 #define V_dyn_expire_lock VNET(dyn_expire_lock) 261 #define V_dyn_bucket_lock VNET(dyn_bucket_lock) 262 263 /* 264 * Bucket's add/delete generation versions. 265 */ 266 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv4_add); 267 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv4_del); 268 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv4_parent_add); 269 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv4_parent_del); 270 #define V_dyn_ipv4_add VNET(dyn_ipv4_add) 271 #define V_dyn_ipv4_del VNET(dyn_ipv4_del) 272 #define V_dyn_ipv4_parent_add VNET(dyn_ipv4_parent_add) 273 #define V_dyn_ipv4_parent_del VNET(dyn_ipv4_parent_del) 274 275 #ifdef INET6 276 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv6_add); 277 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv6_del); 278 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv6_parent_add); 279 VNET_DEFINE_STATIC(uint32_t *, dyn_ipv6_parent_del); 280 #define V_dyn_ipv6_add VNET(dyn_ipv6_add) 281 #define V_dyn_ipv6_del VNET(dyn_ipv6_del) 282 #define V_dyn_ipv6_parent_add VNET(dyn_ipv6_parent_add) 283 #define V_dyn_ipv6_parent_del VNET(dyn_ipv6_parent_del) 284 #endif /* INET6 */ 285 286 #define DYN_BUCKET(h, b) ((h) & (b - 1)) 287 #define DYN_BUCKET_VERSION(b, v) ck_pr_load_32(&V_dyn_ ## v[(b)]) 288 #define DYN_BUCKET_VERSION_BUMP(b, v) ck_pr_inc_32(&V_dyn_ ## v[(b)]) 289 290 #define DYN_BUCKET_LOCK_INIT(lock, b) \ 291 mtx_init(&lock[(b)], "IPFW dynamic bucket", NULL, MTX_DEF) 292 #define DYN_BUCKET_LOCK_DESTROY(lock, b) mtx_destroy(&lock[(b)]) 293 #define DYN_BUCKET_LOCK(b) mtx_lock(&V_dyn_bucket_lock[(b)]) 294 #define DYN_BUCKET_UNLOCK(b) mtx_unlock(&V_dyn_bucket_lock[(b)]) 295 #define DYN_BUCKET_ASSERT(b) mtx_assert(&V_dyn_bucket_lock[(b)], MA_OWNED) 296 297 #define DYN_EXPIRED_LOCK_INIT() \ 298 mtx_init(&V_dyn_expire_lock, "IPFW expired states list", NULL, MTX_DEF) 299 #define DYN_EXPIRED_LOCK_DESTROY() mtx_destroy(&V_dyn_expire_lock) 300 #define DYN_EXPIRED_LOCK() mtx_lock(&V_dyn_expire_lock) 301 #define DYN_EXPIRED_UNLOCK() mtx_unlock(&V_dyn_expire_lock) 302 303 VNET_DEFINE_STATIC(uint32_t, dyn_buckets_max); 304 VNET_DEFINE_STATIC(uint32_t, curr_dyn_buckets); 305 VNET_DEFINE_STATIC(struct callout, dyn_timeout); 306 #define V_dyn_buckets_max VNET(dyn_buckets_max) 307 #define V_curr_dyn_buckets VNET(curr_dyn_buckets) 308 #define V_dyn_timeout VNET(dyn_timeout) 309 310 /* Maximum length of states chain in a bucket */ 311 VNET_DEFINE_STATIC(uint32_t, curr_max_length); 312 #define V_curr_max_length VNET(curr_max_length) 313 314 VNET_DEFINE_STATIC(uint32_t, dyn_keep_states); 315 #define V_dyn_keep_states VNET(dyn_keep_states) 316 317 VNET_DEFINE_STATIC(uma_zone_t, dyn_data_zone); 318 VNET_DEFINE_STATIC(uma_zone_t, dyn_parent_zone); 319 VNET_DEFINE_STATIC(uma_zone_t, dyn_ipv4_zone); 320 #ifdef INET6 321 VNET_DEFINE_STATIC(uma_zone_t, dyn_ipv6_zone); 322 #define V_dyn_ipv6_zone VNET(dyn_ipv6_zone) 323 #endif /* INET6 */ 324 #define V_dyn_data_zone VNET(dyn_data_zone) 325 #define V_dyn_parent_zone VNET(dyn_parent_zone) 326 #define V_dyn_ipv4_zone VNET(dyn_ipv4_zone) 327 328 /* 329 * Timeouts for various events in handing dynamic rules. 330 */ 331 VNET_DEFINE_STATIC(uint32_t, dyn_ack_lifetime); 332 VNET_DEFINE_STATIC(uint32_t, dyn_syn_lifetime); 333 VNET_DEFINE_STATIC(uint32_t, dyn_fin_lifetime); 334 VNET_DEFINE_STATIC(uint32_t, dyn_rst_lifetime); 335 VNET_DEFINE_STATIC(uint32_t, dyn_udp_lifetime); 336 VNET_DEFINE_STATIC(uint32_t, dyn_short_lifetime); 337 338 #define V_dyn_ack_lifetime VNET(dyn_ack_lifetime) 339 #define V_dyn_syn_lifetime VNET(dyn_syn_lifetime) 340 #define V_dyn_fin_lifetime VNET(dyn_fin_lifetime) 341 #define V_dyn_rst_lifetime VNET(dyn_rst_lifetime) 342 #define V_dyn_udp_lifetime VNET(dyn_udp_lifetime) 343 #define V_dyn_short_lifetime VNET(dyn_short_lifetime) 344 345 /* 346 * Keepalives are sent if dyn_keepalive is set. They are sent every 347 * dyn_keepalive_period seconds, in the last dyn_keepalive_interval 348 * seconds of lifetime of a rule. 349 * dyn_rst_lifetime and dyn_fin_lifetime should be strictly lower 350 * than dyn_keepalive_period. 351 */ 352 #define DYN_KEEPALIVE_MAXQ 512 353 VNET_DEFINE_STATIC(uint32_t, dyn_keepalive_interval); 354 VNET_DEFINE_STATIC(uint32_t, dyn_keepalive_period); 355 VNET_DEFINE_STATIC(uint32_t, dyn_keepalive); 356 VNET_DEFINE_STATIC(time_t, dyn_keepalive_last); 357 358 #define V_dyn_keepalive_interval VNET(dyn_keepalive_interval) 359 #define V_dyn_keepalive_period VNET(dyn_keepalive_period) 360 #define V_dyn_keepalive VNET(dyn_keepalive) 361 #define V_dyn_keepalive_last VNET(dyn_keepalive_last) 362 363 VNET_DEFINE_STATIC(uint32_t, dyn_max); /* max # of dynamic states */ 364 VNET_DEFINE_STATIC(uint32_t, dyn_count); /* number of states */ 365 VNET_DEFINE_STATIC(uint32_t, dyn_parent_max); /* max # of parent states */ 366 VNET_DEFINE_STATIC(uint32_t, dyn_parent_count); /* number of parent states */ 367 368 #define V_dyn_max VNET(dyn_max) 369 #define V_dyn_count VNET(dyn_count) 370 #define V_dyn_parent_max VNET(dyn_parent_max) 371 #define V_dyn_parent_count VNET(dyn_parent_count) 372 373 #define DYN_COUNT_DEC(name) do { \ 374 MPASS((V_ ## name) > 0); \ 375 ck_pr_dec_32(&(V_ ## name)); \ 376 } while (0) 377 #define DYN_COUNT_INC(name) ck_pr_inc_32(&(V_ ## name)) 378 #define DYN_COUNT(name) ck_pr_load_32(&(V_ ## name)) 379 380 static time_t last_log; /* Log ratelimiting */ 381 382 /* 383 * Get/set maximum number of dynamic states in given VNET instance. 384 */ 385 static int 386 sysctl_dyn_max(SYSCTL_HANDLER_ARGS) 387 { 388 uint32_t nstates; 389 int error; 390 391 nstates = V_dyn_max; 392 error = sysctl_handle_32(oidp, &nstates, 0, req); 393 /* Read operation or some error */ 394 if ((error != 0) || (req->newptr == NULL)) 395 return (error); 396 397 V_dyn_max = nstates; 398 uma_zone_set_max(V_dyn_data_zone, V_dyn_max); 399 return (0); 400 } 401 402 static int 403 sysctl_dyn_parent_max(SYSCTL_HANDLER_ARGS) 404 { 405 uint32_t nstates; 406 int error; 407 408 nstates = V_dyn_parent_max; 409 error = sysctl_handle_32(oidp, &nstates, 0, req); 410 /* Read operation or some error */ 411 if ((error != 0) || (req->newptr == NULL)) 412 return (error); 413 414 V_dyn_parent_max = nstates; 415 uma_zone_set_max(V_dyn_parent_zone, V_dyn_parent_max); 416 return (0); 417 } 418 419 static int 420 sysctl_dyn_buckets(SYSCTL_HANDLER_ARGS) 421 { 422 uint32_t nbuckets; 423 int error; 424 425 nbuckets = V_dyn_buckets_max; 426 error = sysctl_handle_32(oidp, &nbuckets, 0, req); 427 /* Read operation or some error */ 428 if ((error != 0) || (req->newptr == NULL)) 429 return (error); 430 431 if (nbuckets > 256) 432 V_dyn_buckets_max = 1 << fls(nbuckets - 1); 433 else 434 return (EINVAL); 435 return (0); 436 } 437 438 SYSCTL_DECL(_net_inet_ip_fw); 439 440 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_count, 441 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(dyn_count), 0, 442 "Current number of dynamic states."); 443 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_parent_count, 444 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(dyn_parent_count), 0, 445 "Current number of parent states. "); 446 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, curr_dyn_buckets, 447 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(curr_dyn_buckets), 0, 448 "Current number of buckets for states hash table."); 449 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, curr_max_length, 450 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(curr_max_length), 0, 451 "Current maximum length of states chains in hash buckets."); 452 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_buckets, 453 CTLFLAG_VNET | CTLTYPE_U32 | CTLFLAG_RW, 0, 0, sysctl_dyn_buckets, 454 "IU", "Max number of buckets for dynamic states hash table."); 455 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_max, 456 CTLFLAG_VNET | CTLTYPE_U32 | CTLFLAG_RW, 0, 0, sysctl_dyn_max, 457 "IU", "Max number of dynamic states."); 458 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_parent_max, 459 CTLFLAG_VNET | CTLTYPE_U32 | CTLFLAG_RW, 0, 0, sysctl_dyn_parent_max, 460 "IU", "Max number of parent dynamic states."); 461 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_ack_lifetime, 462 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_ack_lifetime), 0, 463 "Lifetime of dynamic states for TCP ACK."); 464 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_syn_lifetime, 465 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_syn_lifetime), 0, 466 "Lifetime of dynamic states for TCP SYN."); 467 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_fin_lifetime, 468 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_fin_lifetime), 0, 469 "Lifetime of dynamic states for TCP FIN."); 470 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_rst_lifetime, 471 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_rst_lifetime), 0, 472 "Lifetime of dynamic states for TCP RST."); 473 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_udp_lifetime, 474 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_udp_lifetime), 0, 475 "Lifetime of dynamic states for UDP."); 476 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_short_lifetime, 477 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_short_lifetime), 0, 478 "Lifetime of dynamic states for other situations."); 479 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_keepalive, 480 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_keepalive), 0, 481 "Enable keepalives for dynamic states."); 482 SYSCTL_U32(_net_inet_ip_fw, OID_AUTO, dyn_keep_states, 483 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(dyn_keep_states), 0, 484 "Do not flush dynamic states on rule deletion"); 485 486 487 #ifdef IPFIREWALL_DYNDEBUG 488 #define DYN_DEBUG(fmt, ...) do { \ 489 printf("%s: " fmt "\n", __func__, __VA_ARGS__); \ 490 } while (0) 491 #else 492 #define DYN_DEBUG(fmt, ...) 493 #endif /* !IPFIREWALL_DYNDEBUG */ 494 495 #ifdef INET6 496 /* Functions to work with IPv6 states */ 497 static struct dyn_ipv6_state *dyn_lookup_ipv6_state( 498 const struct ipfw_flow_id *, uint32_t, const void *, 499 struct ipfw_dyn_info *, int); 500 static int dyn_lookup_ipv6_state_locked(const struct ipfw_flow_id *, 501 uint32_t, const void *, int, uint32_t, uint16_t); 502 static struct dyn_ipv6_state *dyn_alloc_ipv6_state( 503 const struct ipfw_flow_id *, uint32_t, uint16_t, uint8_t); 504 static int dyn_add_ipv6_state(void *, uint32_t, uint16_t, uint8_t, 505 const struct ipfw_flow_id *, uint32_t, const void *, int, uint32_t, 506 struct ipfw_dyn_info *, uint16_t, uint16_t, uint8_t); 507 static void dyn_export_ipv6_state(const struct dyn_ipv6_state *, 508 ipfw_dyn_rule *); 509 510 static uint32_t dyn_getscopeid(const struct ip_fw_args *); 511 static void dyn_make_keepalive_ipv6(struct mbuf *, const struct in6_addr *, 512 const struct in6_addr *, uint32_t, uint32_t, uint32_t, uint16_t, 513 uint16_t); 514 static void dyn_enqueue_keepalive_ipv6(struct mbufq *, 515 const struct dyn_ipv6_state *); 516 static void dyn_send_keepalive_ipv6(struct ip_fw_chain *); 517 518 static struct dyn_ipv6_state *dyn_lookup_ipv6_parent( 519 const struct ipfw_flow_id *, uint32_t, const void *, uint32_t, uint16_t, 520 uint32_t); 521 static struct dyn_ipv6_state *dyn_lookup_ipv6_parent_locked( 522 const struct ipfw_flow_id *, uint32_t, const void *, uint32_t, uint16_t, 523 uint32_t); 524 static struct dyn_ipv6_state *dyn_add_ipv6_parent(void *, uint32_t, uint16_t, 525 uint8_t, const struct ipfw_flow_id *, uint32_t, uint32_t, uint32_t, 526 uint16_t); 527 #endif /* INET6 */ 528 529 /* Functions to work with limit states */ 530 static void *dyn_get_parent_state(const struct ipfw_flow_id *, uint32_t, 531 struct ip_fw *, uint32_t, uint32_t, uint16_t); 532 static struct dyn_ipv4_state *dyn_lookup_ipv4_parent( 533 const struct ipfw_flow_id *, const void *, uint32_t, uint16_t, uint32_t); 534 static struct dyn_ipv4_state *dyn_lookup_ipv4_parent_locked( 535 const struct ipfw_flow_id *, const void *, uint32_t, uint16_t, uint32_t); 536 static struct dyn_parent *dyn_alloc_parent(void *, uint32_t, uint16_t, 537 uint8_t, uint32_t); 538 static struct dyn_ipv4_state *dyn_add_ipv4_parent(void *, uint32_t, uint16_t, 539 uint8_t, const struct ipfw_flow_id *, uint32_t, uint32_t, uint16_t); 540 541 static void dyn_tick(void *); 542 static void dyn_expire_states(struct ip_fw_chain *, ipfw_range_tlv *); 543 static void dyn_free_states(struct ip_fw_chain *); 544 static void dyn_export_parent(const struct dyn_parent *, uint16_t, 545 ipfw_dyn_rule *); 546 static void dyn_export_data(const struct dyn_data *, uint16_t, uint8_t, 547 ipfw_dyn_rule *); 548 static uint32_t dyn_update_tcp_state(struct dyn_data *, 549 const struct ipfw_flow_id *, const struct tcphdr *, int); 550 static void dyn_update_proto_state(struct dyn_data *, 551 const struct ipfw_flow_id *, const void *, int, int); 552 553 /* Functions to work with IPv4 states */ 554 struct dyn_ipv4_state *dyn_lookup_ipv4_state(const struct ipfw_flow_id *, 555 const void *, struct ipfw_dyn_info *, int); 556 static int dyn_lookup_ipv4_state_locked(const struct ipfw_flow_id *, 557 const void *, int, uint32_t, uint16_t); 558 static struct dyn_ipv4_state *dyn_alloc_ipv4_state( 559 const struct ipfw_flow_id *, uint16_t, uint8_t); 560 static int dyn_add_ipv4_state(void *, uint32_t, uint16_t, uint8_t, 561 const struct ipfw_flow_id *, const void *, int, uint32_t, 562 struct ipfw_dyn_info *, uint16_t, uint16_t, uint8_t); 563 static void dyn_export_ipv4_state(const struct dyn_ipv4_state *, 564 ipfw_dyn_rule *); 565 566 /* 567 * Named states support. 568 */ 569 static char *default_state_name = "default"; 570 struct dyn_state_obj { 571 struct named_object no; 572 char name[64]; 573 }; 574 575 #define DYN_STATE_OBJ(ch, cmd) \ 576 ((struct dyn_state_obj *)SRV_OBJECT(ch, (cmd)->arg1)) 577 /* 578 * Classifier callback. 579 * Return 0 if opcode contains object that should be referenced 580 * or rewritten. 581 */ 582 static int 583 dyn_classify(ipfw_insn *cmd, uint16_t *puidx, uint8_t *ptype) 584 { 585 586 DYN_DEBUG("opcode %d, arg1 %d", cmd->opcode, cmd->arg1); 587 /* Don't rewrite "check-state any" */ 588 if (cmd->arg1 == 0 && 589 cmd->opcode == O_CHECK_STATE) 590 return (1); 591 592 *puidx = cmd->arg1; 593 *ptype = 0; 594 return (0); 595 } 596 597 static void 598 dyn_update(ipfw_insn *cmd, uint16_t idx) 599 { 600 601 cmd->arg1 = idx; 602 DYN_DEBUG("opcode %d, arg1 %d", cmd->opcode, cmd->arg1); 603 } 604 605 static int 606 dyn_findbyname(struct ip_fw_chain *ch, struct tid_info *ti, 607 struct named_object **pno) 608 { 609 ipfw_obj_ntlv *ntlv; 610 const char *name; 611 612 DYN_DEBUG("uidx %d", ti->uidx); 613 if (ti->uidx != 0) { 614 if (ti->tlvs == NULL) 615 return (EINVAL); 616 /* Search ntlv in the buffer provided by user */ 617 ntlv = ipfw_find_name_tlv_type(ti->tlvs, ti->tlen, ti->uidx, 618 IPFW_TLV_STATE_NAME); 619 if (ntlv == NULL) 620 return (EINVAL); 621 name = ntlv->name; 622 } else 623 name = default_state_name; 624 /* 625 * Search named object with corresponding name. 626 * Since states objects are global - ignore the set value 627 * and use zero instead. 628 */ 629 *pno = ipfw_objhash_lookup_name_type(CHAIN_TO_SRV(ch), 0, 630 IPFW_TLV_STATE_NAME, name); 631 /* 632 * We always return success here. 633 * The caller will check *pno and mark object as unresolved, 634 * then it will automatically create "default" object. 635 */ 636 return (0); 637 } 638 639 static struct named_object * 640 dyn_findbykidx(struct ip_fw_chain *ch, uint16_t idx) 641 { 642 643 DYN_DEBUG("kidx %d", idx); 644 return (ipfw_objhash_lookup_kidx(CHAIN_TO_SRV(ch), idx)); 645 } 646 647 static int 648 dyn_create(struct ip_fw_chain *ch, struct tid_info *ti, 649 uint16_t *pkidx) 650 { 651 struct namedobj_instance *ni; 652 struct dyn_state_obj *obj; 653 struct named_object *no; 654 ipfw_obj_ntlv *ntlv; 655 char *name; 656 657 DYN_DEBUG("uidx %d", ti->uidx); 658 if (ti->uidx != 0) { 659 if (ti->tlvs == NULL) 660 return (EINVAL); 661 ntlv = ipfw_find_name_tlv_type(ti->tlvs, ti->tlen, ti->uidx, 662 IPFW_TLV_STATE_NAME); 663 if (ntlv == NULL) 664 return (EINVAL); 665 name = ntlv->name; 666 } else 667 name = default_state_name; 668 669 ni = CHAIN_TO_SRV(ch); 670 obj = malloc(sizeof(*obj), M_IPFW, M_WAITOK | M_ZERO); 671 obj->no.name = obj->name; 672 obj->no.etlv = IPFW_TLV_STATE_NAME; 673 strlcpy(obj->name, name, sizeof(obj->name)); 674 675 IPFW_UH_WLOCK(ch); 676 no = ipfw_objhash_lookup_name_type(ni, 0, 677 IPFW_TLV_STATE_NAME, name); 678 if (no != NULL) { 679 /* 680 * Object is already created. 681 * Just return its kidx and bump refcount. 682 */ 683 *pkidx = no->kidx; 684 no->refcnt++; 685 IPFW_UH_WUNLOCK(ch); 686 free(obj, M_IPFW); 687 DYN_DEBUG("\tfound kidx %d", *pkidx); 688 return (0); 689 } 690 if (ipfw_objhash_alloc_idx(ni, &obj->no.kidx) != 0) { 691 DYN_DEBUG("\talloc_idx failed for %s", name); 692 IPFW_UH_WUNLOCK(ch); 693 free(obj, M_IPFW); 694 return (ENOSPC); 695 } 696 ipfw_objhash_add(ni, &obj->no); 697 SRV_OBJECT(ch, obj->no.kidx) = obj; 698 obj->no.refcnt++; 699 *pkidx = obj->no.kidx; 700 IPFW_UH_WUNLOCK(ch); 701 DYN_DEBUG("\tcreated kidx %d", *pkidx); 702 return (0); 703 } 704 705 static void 706 dyn_destroy(struct ip_fw_chain *ch, struct named_object *no) 707 { 708 struct dyn_state_obj *obj; 709 710 IPFW_UH_WLOCK_ASSERT(ch); 711 712 KASSERT(no->refcnt == 1, 713 ("Destroying object '%s' (type %u, idx %u) with refcnt %u", 714 no->name, no->etlv, no->kidx, no->refcnt)); 715 DYN_DEBUG("kidx %d", no->kidx); 716 obj = SRV_OBJECT(ch, no->kidx); 717 SRV_OBJECT(ch, no->kidx) = NULL; 718 ipfw_objhash_del(CHAIN_TO_SRV(ch), no); 719 ipfw_objhash_free_idx(CHAIN_TO_SRV(ch), no->kidx); 720 721 free(obj, M_IPFW); 722 } 723 724 static struct opcode_obj_rewrite dyn_opcodes[] = { 725 { 726 O_KEEP_STATE, IPFW_TLV_STATE_NAME, 727 dyn_classify, dyn_update, 728 dyn_findbyname, dyn_findbykidx, 729 dyn_create, dyn_destroy 730 }, 731 { 732 O_CHECK_STATE, IPFW_TLV_STATE_NAME, 733 dyn_classify, dyn_update, 734 dyn_findbyname, dyn_findbykidx, 735 dyn_create, dyn_destroy 736 }, 737 { 738 O_PROBE_STATE, IPFW_TLV_STATE_NAME, 739 dyn_classify, dyn_update, 740 dyn_findbyname, dyn_findbykidx, 741 dyn_create, dyn_destroy 742 }, 743 { 744 O_LIMIT, IPFW_TLV_STATE_NAME, 745 dyn_classify, dyn_update, 746 dyn_findbyname, dyn_findbykidx, 747 dyn_create, dyn_destroy 748 }, 749 }; 750 751 /* 752 * IMPORTANT: the hash function for dynamic rules must be commutative 753 * in source and destination (ip,port), because rules are bidirectional 754 * and we want to find both in the same bucket. 755 */ 756 #ifndef IPFIREWALL_JENKINSHASH 757 static __inline uint32_t 758 hash_packet(const struct ipfw_flow_id *id) 759 { 760 uint32_t i; 761 762 #ifdef INET6 763 if (IS_IP6_FLOW_ID(id)) 764 i = ntohl((id->dst_ip6.__u6_addr.__u6_addr32[2]) ^ 765 (id->dst_ip6.__u6_addr.__u6_addr32[3]) ^ 766 (id->src_ip6.__u6_addr.__u6_addr32[2]) ^ 767 (id->src_ip6.__u6_addr.__u6_addr32[3])); 768 else 769 #endif /* INET6 */ 770 i = (id->dst_ip) ^ (id->src_ip); 771 i ^= (id->dst_port) ^ (id->src_port); 772 return (i); 773 } 774 775 static __inline uint32_t 776 hash_parent(const struct ipfw_flow_id *id, const void *rule) 777 { 778 779 return (hash_packet(id) ^ ((uintptr_t)rule)); 780 } 781 782 #else /* IPFIREWALL_JENKINSHASH */ 783 784 VNET_DEFINE_STATIC(uint32_t, dyn_hashseed); 785 #define V_dyn_hashseed VNET(dyn_hashseed) 786 787 static __inline int 788 addrcmp4(const struct ipfw_flow_id *id) 789 { 790 791 if (id->src_ip < id->dst_ip) 792 return (0); 793 if (id->src_ip > id->dst_ip) 794 return (1); 795 if (id->src_port <= id->dst_port) 796 return (0); 797 return (1); 798 } 799 800 #ifdef INET6 801 static __inline int 802 addrcmp6(const struct ipfw_flow_id *id) 803 { 804 int ret; 805 806 ret = memcmp(&id->src_ip6, &id->dst_ip6, sizeof(struct in6_addr)); 807 if (ret < 0) 808 return (0); 809 if (ret > 0) 810 return (1); 811 if (id->src_port <= id->dst_port) 812 return (0); 813 return (1); 814 } 815 816 static __inline uint32_t 817 hash_packet6(const struct ipfw_flow_id *id) 818 { 819 struct tuple6 { 820 struct in6_addr addr[2]; 821 uint16_t port[2]; 822 } t6; 823 824 if (addrcmp6(id) == 0) { 825 t6.addr[0] = id->src_ip6; 826 t6.addr[1] = id->dst_ip6; 827 t6.port[0] = id->src_port; 828 t6.port[1] = id->dst_port; 829 } else { 830 t6.addr[0] = id->dst_ip6; 831 t6.addr[1] = id->src_ip6; 832 t6.port[0] = id->dst_port; 833 t6.port[1] = id->src_port; 834 } 835 return (jenkins_hash32((const uint32_t *)&t6, 836 sizeof(t6) / sizeof(uint32_t), V_dyn_hashseed)); 837 } 838 #endif 839 840 static __inline uint32_t 841 hash_packet(const struct ipfw_flow_id *id) 842 { 843 struct tuple4 { 844 in_addr_t addr[2]; 845 uint16_t port[2]; 846 } t4; 847 848 if (IS_IP4_FLOW_ID(id)) { 849 /* All fields are in host byte order */ 850 if (addrcmp4(id) == 0) { 851 t4.addr[0] = id->src_ip; 852 t4.addr[1] = id->dst_ip; 853 t4.port[0] = id->src_port; 854 t4.port[1] = id->dst_port; 855 } else { 856 t4.addr[0] = id->dst_ip; 857 t4.addr[1] = id->src_ip; 858 t4.port[0] = id->dst_port; 859 t4.port[1] = id->src_port; 860 } 861 return (jenkins_hash32((const uint32_t *)&t4, 862 sizeof(t4) / sizeof(uint32_t), V_dyn_hashseed)); 863 } else 864 #ifdef INET6 865 if (IS_IP6_FLOW_ID(id)) 866 return (hash_packet6(id)); 867 #endif 868 return (0); 869 } 870 871 static __inline uint32_t 872 hash_parent(const struct ipfw_flow_id *id, const void *rule) 873 { 874 875 return (jenkins_hash32((const uint32_t *)&rule, 876 sizeof(rule) / sizeof(uint32_t), hash_packet(id))); 877 } 878 #endif /* IPFIREWALL_JENKINSHASH */ 879 880 /* 881 * Print customizable flow id description via log(9) facility. 882 */ 883 static void 884 print_dyn_rule_flags(const struct ipfw_flow_id *id, int dyn_type, 885 int log_flags, char *prefix, char *postfix) 886 { 887 struct in_addr da; 888 #ifdef INET6 889 char src[INET6_ADDRSTRLEN], dst[INET6_ADDRSTRLEN]; 890 #else 891 char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN]; 892 #endif 893 894 #ifdef INET6 895 if (IS_IP6_FLOW_ID(id)) { 896 ip6_sprintf(src, &id->src_ip6); 897 ip6_sprintf(dst, &id->dst_ip6); 898 } else 899 #endif 900 { 901 da.s_addr = htonl(id->src_ip); 902 inet_ntop(AF_INET, &da, src, sizeof(src)); 903 da.s_addr = htonl(id->dst_ip); 904 inet_ntop(AF_INET, &da, dst, sizeof(dst)); 905 } 906 log(log_flags, "ipfw: %s type %d %s %d -> %s %d, %d %s\n", 907 prefix, dyn_type, src, id->src_port, dst, 908 id->dst_port, V_dyn_count, postfix); 909 } 910 911 #define print_dyn_rule(id, dtype, prefix, postfix) \ 912 print_dyn_rule_flags(id, dtype, LOG_DEBUG, prefix, postfix) 913 914 #define TIME_LEQ(a,b) ((int)((a)-(b)) <= 0) 915 #define TIME_LE(a,b) ((int)((a)-(b)) < 0) 916 #define _SEQ_GE(a,b) ((int)((a)-(b)) >= 0) 917 #define BOTH_SYN (TH_SYN | (TH_SYN << 8)) 918 #define BOTH_FIN (TH_FIN | (TH_FIN << 8)) 919 #define TCP_FLAGS (TH_FLAGS | (TH_FLAGS << 8)) 920 #define ACK_FWD 0x00010000 /* fwd ack seen */ 921 #define ACK_REV 0x00020000 /* rev ack seen */ 922 #define ACK_BOTH (ACK_FWD | ACK_REV) 923 924 static uint32_t 925 dyn_update_tcp_state(struct dyn_data *data, const struct ipfw_flow_id *pkt, 926 const struct tcphdr *tcp, int dir) 927 { 928 uint32_t ack, expire; 929 uint32_t state, old; 930 uint8_t th_flags; 931 932 expire = data->expire; 933 old = state = data->state; 934 th_flags = pkt->_flags & (TH_FIN | TH_SYN | TH_RST); 935 state |= (dir == MATCH_FORWARD) ? th_flags: (th_flags << 8); 936 switch (state & TCP_FLAGS) { 937 case TH_SYN: /* opening */ 938 expire = time_uptime + V_dyn_syn_lifetime; 939 break; 940 941 case BOTH_SYN: /* move to established */ 942 case BOTH_SYN | TH_FIN: /* one side tries to close */ 943 case BOTH_SYN | (TH_FIN << 8): 944 if (tcp == NULL) 945 break; 946 ack = ntohl(tcp->th_ack); 947 if (dir == MATCH_FORWARD) { 948 if (data->ack_fwd == 0 || 949 _SEQ_GE(ack, data->ack_fwd)) { 950 state |= ACK_FWD; 951 if (data->ack_fwd != ack) 952 ck_pr_store_32(&data->ack_fwd, ack); 953 } 954 } else { 955 if (data->ack_rev == 0 || 956 _SEQ_GE(ack, data->ack_rev)) { 957 state |= ACK_REV; 958 if (data->ack_rev != ack) 959 ck_pr_store_32(&data->ack_rev, ack); 960 } 961 } 962 if ((state & ACK_BOTH) == ACK_BOTH) { 963 /* 964 * Set expire time to V_dyn_ack_lifetime only if 965 * we got ACKs for both directions. 966 * We use XOR here to avoid possible state 967 * overwriting in concurrent thread. 968 */ 969 expire = time_uptime + V_dyn_ack_lifetime; 970 ck_pr_xor_32(&data->state, ACK_BOTH); 971 } else if ((data->state & ACK_BOTH) != (state & ACK_BOTH)) 972 ck_pr_or_32(&data->state, state & ACK_BOTH); 973 break; 974 975 case BOTH_SYN | BOTH_FIN: /* both sides closed */ 976 if (V_dyn_fin_lifetime >= V_dyn_keepalive_period) 977 V_dyn_fin_lifetime = V_dyn_keepalive_period - 1; 978 expire = time_uptime + V_dyn_fin_lifetime; 979 break; 980 981 default: 982 if (V_dyn_keepalive != 0 && 983 V_dyn_rst_lifetime >= V_dyn_keepalive_period) 984 V_dyn_rst_lifetime = V_dyn_keepalive_period - 1; 985 expire = time_uptime + V_dyn_rst_lifetime; 986 } 987 /* Save TCP state if it was changed */ 988 if ((state & TCP_FLAGS) != (old & TCP_FLAGS)) 989 ck_pr_or_32(&data->state, state & TCP_FLAGS); 990 return (expire); 991 } 992 993 /* 994 * Update ULP specific state. 995 * For TCP we keep sequence numbers and flags. For other protocols 996 * currently we update only expire time. Packets and bytes counters 997 * are also updated here. 998 */ 999 static void 1000 dyn_update_proto_state(struct dyn_data *data, const struct ipfw_flow_id *pkt, 1001 const void *ulp, int pktlen, int dir) 1002 { 1003 uint32_t expire; 1004 1005 /* NOTE: we are in critical section here. */ 1006 switch (pkt->proto) { 1007 case IPPROTO_UDP: 1008 case IPPROTO_UDPLITE: 1009 expire = time_uptime + V_dyn_udp_lifetime; 1010 break; 1011 case IPPROTO_TCP: 1012 expire = dyn_update_tcp_state(data, pkt, ulp, dir); 1013 break; 1014 default: 1015 expire = time_uptime + V_dyn_short_lifetime; 1016 } 1017 /* 1018 * Expiration timer has the per-second granularity, no need to update 1019 * it every time when state is matched. 1020 */ 1021 if (data->expire != expire) 1022 ck_pr_store_32(&data->expire, expire); 1023 1024 if (dir == MATCH_FORWARD) 1025 DYN_COUNTER_INC(data, fwd, pktlen); 1026 else 1027 DYN_COUNTER_INC(data, rev, pktlen); 1028 } 1029 1030 /* 1031 * Lookup IPv4 state. 1032 * Must be called in critical section. 1033 */ 1034 struct dyn_ipv4_state * 1035 dyn_lookup_ipv4_state(const struct ipfw_flow_id *pkt, const void *ulp, 1036 struct ipfw_dyn_info *info, int pktlen) 1037 { 1038 struct dyn_ipv4_state *s; 1039 uint32_t version, bucket; 1040 1041 bucket = DYN_BUCKET(info->hashval, V_curr_dyn_buckets); 1042 info->version = DYN_BUCKET_VERSION(bucket, ipv4_add); 1043 restart: 1044 version = DYN_BUCKET_VERSION(bucket, ipv4_del); 1045 CK_SLIST_FOREACH(s, &V_dyn_ipv4[bucket], entry) { 1046 DYNSTATE_PROTECT(s); 1047 if (version != DYN_BUCKET_VERSION(bucket, ipv4_del)) 1048 goto restart; 1049 if (s->proto != pkt->proto) 1050 continue; 1051 if (info->kidx != 0 && s->kidx != info->kidx) 1052 continue; 1053 if (s->sport == pkt->src_port && s->dport == pkt->dst_port && 1054 s->src == pkt->src_ip && s->dst == pkt->dst_ip) { 1055 info->direction = MATCH_FORWARD; 1056 break; 1057 } 1058 if (s->sport == pkt->dst_port && s->dport == pkt->src_port && 1059 s->src == pkt->dst_ip && s->dst == pkt->src_ip) { 1060 info->direction = MATCH_REVERSE; 1061 break; 1062 } 1063 } 1064 1065 if (s != NULL) 1066 dyn_update_proto_state(s->data, pkt, ulp, pktlen, 1067 info->direction); 1068 return (s); 1069 } 1070 1071 /* 1072 * Lookup IPv4 state. 1073 * Simplifed version is used to check that matching state doesn't exist. 1074 */ 1075 static int 1076 dyn_lookup_ipv4_state_locked(const struct ipfw_flow_id *pkt, 1077 const void *ulp, int pktlen, uint32_t bucket, uint16_t kidx) 1078 { 1079 struct dyn_ipv4_state *s; 1080 int dir; 1081 1082 dir = MATCH_NONE; 1083 DYN_BUCKET_ASSERT(bucket); 1084 CK_SLIST_FOREACH(s, &V_dyn_ipv4[bucket], entry) { 1085 if (s->proto != pkt->proto || 1086 s->kidx != kidx) 1087 continue; 1088 if (s->sport == pkt->src_port && 1089 s->dport == pkt->dst_port && 1090 s->src == pkt->src_ip && s->dst == pkt->dst_ip) { 1091 dir = MATCH_FORWARD; 1092 break; 1093 } 1094 if (s->sport == pkt->dst_port && s->dport == pkt->src_port && 1095 s->src == pkt->dst_ip && s->dst == pkt->src_ip) { 1096 dir = MATCH_REVERSE; 1097 break; 1098 } 1099 } 1100 if (s != NULL) 1101 dyn_update_proto_state(s->data, pkt, ulp, pktlen, dir); 1102 return (s != NULL); 1103 } 1104 1105 struct dyn_ipv4_state * 1106 dyn_lookup_ipv4_parent(const struct ipfw_flow_id *pkt, const void *rule, 1107 uint32_t ruleid, uint16_t rulenum, uint32_t hashval) 1108 { 1109 struct dyn_ipv4_state *s; 1110 uint32_t version, bucket; 1111 1112 bucket = DYN_BUCKET(hashval, V_curr_dyn_buckets); 1113 restart: 1114 version = DYN_BUCKET_VERSION(bucket, ipv4_parent_del); 1115 CK_SLIST_FOREACH(s, &V_dyn_ipv4_parent[bucket], entry) { 1116 DYNSTATE_PROTECT(s); 1117 if (version != DYN_BUCKET_VERSION(bucket, ipv4_parent_del)) 1118 goto restart; 1119 /* 1120 * NOTE: we do not need to check kidx, because parent rule 1121 * can not create states with different kidx. 1122 * And parent rule always created for forward direction. 1123 */ 1124 if (s->limit->parent == rule && 1125 s->limit->ruleid == ruleid && 1126 s->limit->rulenum == rulenum && 1127 s->proto == pkt->proto && 1128 s->sport == pkt->src_port && 1129 s->dport == pkt->dst_port && 1130 s->src == pkt->src_ip && s->dst == pkt->dst_ip) { 1131 if (s->limit->expire != time_uptime + 1132 V_dyn_short_lifetime) 1133 ck_pr_store_32(&s->limit->expire, 1134 time_uptime + V_dyn_short_lifetime); 1135 break; 1136 } 1137 } 1138 return (s); 1139 } 1140 1141 static struct dyn_ipv4_state * 1142 dyn_lookup_ipv4_parent_locked(const struct ipfw_flow_id *pkt, 1143 const void *rule, uint32_t ruleid, uint16_t rulenum, uint32_t bucket) 1144 { 1145 struct dyn_ipv4_state *s; 1146 1147 DYN_BUCKET_ASSERT(bucket); 1148 CK_SLIST_FOREACH(s, &V_dyn_ipv4_parent[bucket], entry) { 1149 if (s->limit->parent == rule && 1150 s->limit->ruleid == ruleid && 1151 s->limit->rulenum == rulenum && 1152 s->proto == pkt->proto && 1153 s->sport == pkt->src_port && 1154 s->dport == pkt->dst_port && 1155 s->src == pkt->src_ip && s->dst == pkt->dst_ip) 1156 break; 1157 } 1158 return (s); 1159 } 1160 1161 1162 #ifdef INET6 1163 static uint32_t 1164 dyn_getscopeid(const struct ip_fw_args *args) 1165 { 1166 1167 /* 1168 * If source or destination address is an scopeid address, we need 1169 * determine the scope zone id to resolve address scope ambiguity. 1170 */ 1171 if (IN6_IS_ADDR_LINKLOCAL(&args->f_id.src_ip6) || 1172 IN6_IS_ADDR_LINKLOCAL(&args->f_id.dst_ip6)) { 1173 MPASS(args->oif != NULL || 1174 args->m->m_pkthdr.rcvif != NULL); 1175 return (in6_getscopezone(args->oif != NULL ? args->oif: 1176 args->m->m_pkthdr.rcvif, IPV6_ADDR_SCOPE_LINKLOCAL)); 1177 } 1178 return (0); 1179 } 1180 1181 /* 1182 * Lookup IPv6 state. 1183 * Must be called in critical section. 1184 */ 1185 static struct dyn_ipv6_state * 1186 dyn_lookup_ipv6_state(const struct ipfw_flow_id *pkt, uint32_t zoneid, 1187 const void *ulp, struct ipfw_dyn_info *info, int pktlen) 1188 { 1189 struct dyn_ipv6_state *s; 1190 uint32_t version, bucket; 1191 1192 bucket = DYN_BUCKET(info->hashval, V_curr_dyn_buckets); 1193 info->version = DYN_BUCKET_VERSION(bucket, ipv6_add); 1194 restart: 1195 version = DYN_BUCKET_VERSION(bucket, ipv6_del); 1196 CK_SLIST_FOREACH(s, &V_dyn_ipv6[bucket], entry) { 1197 DYNSTATE_PROTECT(s); 1198 if (version != DYN_BUCKET_VERSION(bucket, ipv6_del)) 1199 goto restart; 1200 if (s->proto != pkt->proto || s->zoneid != zoneid) 1201 continue; 1202 if (info->kidx != 0 && s->kidx != info->kidx) 1203 continue; 1204 if (s->sport == pkt->src_port && s->dport == pkt->dst_port && 1205 IN6_ARE_ADDR_EQUAL(&s->src, &pkt->src_ip6) && 1206 IN6_ARE_ADDR_EQUAL(&s->dst, &pkt->dst_ip6)) { 1207 info->direction = MATCH_FORWARD; 1208 break; 1209 } 1210 if (s->sport == pkt->dst_port && s->dport == pkt->src_port && 1211 IN6_ARE_ADDR_EQUAL(&s->src, &pkt->dst_ip6) && 1212 IN6_ARE_ADDR_EQUAL(&s->dst, &pkt->src_ip6)) { 1213 info->direction = MATCH_REVERSE; 1214 break; 1215 } 1216 } 1217 if (s != NULL) 1218 dyn_update_proto_state(s->data, pkt, ulp, pktlen, 1219 info->direction); 1220 return (s); 1221 } 1222 1223 /* 1224 * Lookup IPv6 state. 1225 * Simplifed version is used to check that matching state doesn't exist. 1226 */ 1227 static int 1228 dyn_lookup_ipv6_state_locked(const struct ipfw_flow_id *pkt, uint32_t zoneid, 1229 const void *ulp, int pktlen, uint32_t bucket, uint16_t kidx) 1230 { 1231 struct dyn_ipv6_state *s; 1232 int dir; 1233 1234 dir = MATCH_NONE; 1235 DYN_BUCKET_ASSERT(bucket); 1236 CK_SLIST_FOREACH(s, &V_dyn_ipv6[bucket], entry) { 1237 if (s->proto != pkt->proto || s->kidx != kidx || 1238 s->zoneid != zoneid) 1239 continue; 1240 if (s->sport == pkt->src_port && s->dport == pkt->dst_port && 1241 IN6_ARE_ADDR_EQUAL(&s->src, &pkt->src_ip6) && 1242 IN6_ARE_ADDR_EQUAL(&s->dst, &pkt->dst_ip6)) { 1243 dir = MATCH_FORWARD; 1244 break; 1245 } 1246 if (s->sport == pkt->dst_port && s->dport == pkt->src_port && 1247 IN6_ARE_ADDR_EQUAL(&s->src, &pkt->dst_ip6) && 1248 IN6_ARE_ADDR_EQUAL(&s->dst, &pkt->src_ip6)) { 1249 dir = MATCH_REVERSE; 1250 break; 1251 } 1252 } 1253 if (s != NULL) 1254 dyn_update_proto_state(s->data, pkt, ulp, pktlen, dir); 1255 return (s != NULL); 1256 } 1257 1258 static struct dyn_ipv6_state * 1259 dyn_lookup_ipv6_parent(const struct ipfw_flow_id *pkt, uint32_t zoneid, 1260 const void *rule, uint32_t ruleid, uint16_t rulenum, uint32_t hashval) 1261 { 1262 struct dyn_ipv6_state *s; 1263 uint32_t version, bucket; 1264 1265 bucket = DYN_BUCKET(hashval, V_curr_dyn_buckets); 1266 restart: 1267 version = DYN_BUCKET_VERSION(bucket, ipv6_parent_del); 1268 CK_SLIST_FOREACH(s, &V_dyn_ipv6_parent[bucket], entry) { 1269 DYNSTATE_PROTECT(s); 1270 if (version != DYN_BUCKET_VERSION(bucket, ipv6_parent_del)) 1271 goto restart; 1272 /* 1273 * NOTE: we do not need to check kidx, because parent rule 1274 * can not create states with different kidx. 1275 * Also parent rule always created for forward direction. 1276 */ 1277 if (s->limit->parent == rule && 1278 s->limit->ruleid == ruleid && 1279 s->limit->rulenum == rulenum && 1280 s->proto == pkt->proto && 1281 s->sport == pkt->src_port && 1282 s->dport == pkt->dst_port && s->zoneid == zoneid && 1283 IN6_ARE_ADDR_EQUAL(&s->src, &pkt->src_ip6) && 1284 IN6_ARE_ADDR_EQUAL(&s->dst, &pkt->dst_ip6)) { 1285 if (s->limit->expire != time_uptime + 1286 V_dyn_short_lifetime) 1287 ck_pr_store_32(&s->limit->expire, 1288 time_uptime + V_dyn_short_lifetime); 1289 break; 1290 } 1291 } 1292 return (s); 1293 } 1294 1295 static struct dyn_ipv6_state * 1296 dyn_lookup_ipv6_parent_locked(const struct ipfw_flow_id *pkt, uint32_t zoneid, 1297 const void *rule, uint32_t ruleid, uint16_t rulenum, uint32_t bucket) 1298 { 1299 struct dyn_ipv6_state *s; 1300 1301 DYN_BUCKET_ASSERT(bucket); 1302 CK_SLIST_FOREACH(s, &V_dyn_ipv6_parent[bucket], entry) { 1303 if (s->limit->parent == rule && 1304 s->limit->ruleid == ruleid && 1305 s->limit->rulenum == rulenum && 1306 s->proto == pkt->proto && 1307 s->sport == pkt->src_port && 1308 s->dport == pkt->dst_port && s->zoneid == zoneid && 1309 IN6_ARE_ADDR_EQUAL(&s->src, &pkt->src_ip6) && 1310 IN6_ARE_ADDR_EQUAL(&s->dst, &pkt->dst_ip6)) 1311 break; 1312 } 1313 return (s); 1314 } 1315 1316 #endif /* INET6 */ 1317 1318 /* 1319 * Lookup dynamic state. 1320 * pkt - filled by ipfw_chk() ipfw_flow_id; 1321 * ulp - determined by ipfw_chk() upper level protocol header; 1322 * dyn_info - info about matched state to return back; 1323 * Returns pointer to state's parent rule and dyn_info. If there is 1324 * no state, NULL is returned. 1325 * On match ipfw_dyn_lookup() updates state's counters. 1326 */ 1327 struct ip_fw * 1328 ipfw_dyn_lookup_state(const struct ip_fw_args *args, const void *ulp, 1329 int pktlen, const ipfw_insn *cmd, struct ipfw_dyn_info *info) 1330 { 1331 struct dyn_data *data; 1332 struct ip_fw *rule; 1333 1334 IPFW_RLOCK_ASSERT(&V_layer3_chain); 1335 1336 data = NULL; 1337 rule = NULL; 1338 info->kidx = cmd->arg1; 1339 info->direction = MATCH_NONE; 1340 info->hashval = hash_packet(&args->f_id); 1341 1342 DYNSTATE_CRITICAL_ENTER(); 1343 if (IS_IP4_FLOW_ID(&args->f_id)) { 1344 struct dyn_ipv4_state *s; 1345 1346 s = dyn_lookup_ipv4_state(&args->f_id, ulp, info, pktlen); 1347 if (s != NULL) { 1348 /* 1349 * Dynamic states are created using the same 5-tuple, 1350 * so it is assumed, that parent rule for O_LIMIT 1351 * state has the same address family. 1352 */ 1353 data = s->data; 1354 if (s->type == O_LIMIT) { 1355 s = data->parent; 1356 rule = s->limit->parent; 1357 } else 1358 rule = data->parent; 1359 } 1360 } 1361 #ifdef INET6 1362 else if (IS_IP6_FLOW_ID(&args->f_id)) { 1363 struct dyn_ipv6_state *s; 1364 1365 s = dyn_lookup_ipv6_state(&args->f_id, dyn_getscopeid(args), 1366 ulp, info, pktlen); 1367 if (s != NULL) { 1368 data = s->data; 1369 if (s->type == O_LIMIT) { 1370 s = data->parent; 1371 rule = s->limit->parent; 1372 } else 1373 rule = data->parent; 1374 } 1375 } 1376 #endif 1377 if (data != NULL) { 1378 /* 1379 * If cached chain id is the same, we can avoid rule index 1380 * lookup. Otherwise do lookup and update chain_id and f_pos. 1381 * It is safe even if there is concurrent thread that want 1382 * update the same state, because chain->id can be changed 1383 * only under IPFW_WLOCK(). 1384 */ 1385 if (data->chain_id != V_layer3_chain.id) { 1386 data->f_pos = ipfw_find_rule(&V_layer3_chain, 1387 data->rulenum, data->ruleid); 1388 /* 1389 * Check that found state has not orphaned. 1390 * When chain->id being changed the parent 1391 * rule can be deleted. If found rule doesn't 1392 * match the parent pointer, consider this 1393 * result as MATCH_NONE and return NULL. 1394 * 1395 * This will lead to creation of new similar state 1396 * that will be added into head of this bucket. 1397 * And the state that we currently have matched 1398 * should be deleted by dyn_expire_states(). 1399 * 1400 * In case when dyn_keep_states is enabled, return 1401 * pointer to default rule and corresponding f_pos 1402 * value. 1403 * XXX: In this case we lose the cache efficiency, 1404 * since f_pos is not cached, because it seems 1405 * there is no easy way to atomically switch 1406 * all fields related to parent rule of given 1407 * state. 1408 */ 1409 if (V_layer3_chain.map[data->f_pos] == rule) { 1410 data->chain_id = V_layer3_chain.id; 1411 info->f_pos = data->f_pos; 1412 } else if (V_dyn_keep_states != 0) { 1413 rule = V_layer3_chain.default_rule; 1414 info->f_pos = V_layer3_chain.n_rules - 1; 1415 } else { 1416 rule = NULL; 1417 info->direction = MATCH_NONE; 1418 DYN_DEBUG("rule %p [%u, %u] is considered " 1419 "invalid in data %p", rule, data->ruleid, 1420 data->rulenum, data); 1421 /* info->f_pos doesn't matter here. */ 1422 } 1423 } else 1424 info->f_pos = data->f_pos; 1425 } 1426 DYNSTATE_CRITICAL_EXIT(); 1427 #if 0 1428 /* 1429 * Return MATCH_NONE if parent rule is in disabled set. 1430 * This will lead to creation of new similar state that 1431 * will be added into head of this bucket. 1432 * 1433 * XXXAE: we need to be able update state's set when parent 1434 * rule set is changed. 1435 */ 1436 if (rule != NULL && (V_set_disable & (1 << rule->set))) { 1437 rule = NULL; 1438 info->direction = MATCH_NONE; 1439 } 1440 #endif 1441 return (rule); 1442 } 1443 1444 static struct dyn_parent * 1445 dyn_alloc_parent(void *parent, uint32_t ruleid, uint16_t rulenum, 1446 uint8_t set, uint32_t hashval) 1447 { 1448 struct dyn_parent *limit; 1449 1450 limit = uma_zalloc(V_dyn_parent_zone, M_NOWAIT | M_ZERO); 1451 if (limit == NULL) { 1452 if (last_log != time_uptime) { 1453 last_log = time_uptime; 1454 log(LOG_DEBUG, 1455 "ipfw: Cannot allocate parent dynamic state, " 1456 "consider increasing " 1457 "net.inet.ip.fw.dyn_parent_max\n"); 1458 } 1459 return (NULL); 1460 } 1461 1462 limit->parent = parent; 1463 limit->ruleid = ruleid; 1464 limit->rulenum = rulenum; 1465 limit->set = set; 1466 limit->hashval = hashval; 1467 limit->expire = time_uptime + V_dyn_short_lifetime; 1468 return (limit); 1469 } 1470 1471 static struct dyn_data * 1472 dyn_alloc_dyndata(void *parent, uint32_t ruleid, uint16_t rulenum, 1473 uint8_t set, const struct ipfw_flow_id *pkt, const void *ulp, int pktlen, 1474 uint32_t hashval, uint16_t fibnum) 1475 { 1476 struct dyn_data *data; 1477 1478 data = uma_zalloc(V_dyn_data_zone, M_NOWAIT | M_ZERO); 1479 if (data == NULL) { 1480 if (last_log != time_uptime) { 1481 last_log = time_uptime; 1482 log(LOG_DEBUG, 1483 "ipfw: Cannot allocate dynamic state, " 1484 "consider increasing net.inet.ip.fw.dyn_max\n"); 1485 } 1486 return (NULL); 1487 } 1488 1489 data->parent = parent; 1490 data->ruleid = ruleid; 1491 data->rulenum = rulenum; 1492 data->set = set; 1493 data->fibnum = fibnum; 1494 data->hashval = hashval; 1495 data->expire = time_uptime + V_dyn_syn_lifetime; 1496 dyn_update_proto_state(data, pkt, ulp, pktlen, MATCH_FORWARD); 1497 return (data); 1498 } 1499 1500 static struct dyn_ipv4_state * 1501 dyn_alloc_ipv4_state(const struct ipfw_flow_id *pkt, uint16_t kidx, 1502 uint8_t type) 1503 { 1504 struct dyn_ipv4_state *s; 1505 1506 s = uma_zalloc(V_dyn_ipv4_zone, M_NOWAIT | M_ZERO); 1507 if (s == NULL) 1508 return (NULL); 1509 1510 s->type = type; 1511 s->kidx = kidx; 1512 s->proto = pkt->proto; 1513 s->sport = pkt->src_port; 1514 s->dport = pkt->dst_port; 1515 s->src = pkt->src_ip; 1516 s->dst = pkt->dst_ip; 1517 return (s); 1518 } 1519 1520 /* 1521 * Add IPv4 parent state. 1522 * Returns pointer to parent state. When it is not NULL we are in 1523 * critical section and pointer protected by hazard pointer. 1524 * When some error occurs, it returns NULL and exit from critical section 1525 * is not needed. 1526 */ 1527 static struct dyn_ipv4_state * 1528 dyn_add_ipv4_parent(void *rule, uint32_t ruleid, uint16_t rulenum, 1529 uint8_t set, const struct ipfw_flow_id *pkt, uint32_t hashval, 1530 uint32_t version, uint16_t kidx) 1531 { 1532 struct dyn_ipv4_state *s; 1533 struct dyn_parent *limit; 1534 uint32_t bucket; 1535 1536 bucket = DYN_BUCKET(hashval, V_curr_dyn_buckets); 1537 DYN_BUCKET_LOCK(bucket); 1538 if (version != DYN_BUCKET_VERSION(bucket, ipv4_parent_add)) { 1539 /* 1540 * Bucket version has been changed since last lookup, 1541 * do lookup again to be sure that state does not exist. 1542 */ 1543 s = dyn_lookup_ipv4_parent_locked(pkt, rule, ruleid, 1544 rulenum, bucket); 1545 if (s != NULL) { 1546 /* 1547 * Simultaneous thread has already created this 1548 * state. Just return it. 1549 */ 1550 DYNSTATE_CRITICAL_ENTER(); 1551 DYNSTATE_PROTECT(s); 1552 DYN_BUCKET_UNLOCK(bucket); 1553 return (s); 1554 } 1555 } 1556 1557 limit = dyn_alloc_parent(rule, ruleid, rulenum, set, hashval); 1558 if (limit == NULL) { 1559 DYN_BUCKET_UNLOCK(bucket); 1560 return (NULL); 1561 } 1562 1563 s = dyn_alloc_ipv4_state(pkt, kidx, O_LIMIT_PARENT); 1564 if (s == NULL) { 1565 DYN_BUCKET_UNLOCK(bucket); 1566 uma_zfree(V_dyn_parent_zone, limit); 1567 return (NULL); 1568 } 1569 1570 s->limit = limit; 1571 CK_SLIST_INSERT_HEAD(&V_dyn_ipv4_parent[bucket], s, entry); 1572 DYN_COUNT_INC(dyn_parent_count); 1573 DYN_BUCKET_VERSION_BUMP(bucket, ipv4_parent_add); 1574 DYNSTATE_CRITICAL_ENTER(); 1575 DYNSTATE_PROTECT(s); 1576 DYN_BUCKET_UNLOCK(bucket); 1577 return (s); 1578 } 1579 1580 static int 1581 dyn_add_ipv4_state(void *parent, uint32_t ruleid, uint16_t rulenum, 1582 uint8_t set, const struct ipfw_flow_id *pkt, const void *ulp, int pktlen, 1583 uint32_t hashval, struct ipfw_dyn_info *info, uint16_t fibnum, 1584 uint16_t kidx, uint8_t type) 1585 { 1586 struct dyn_ipv4_state *s; 1587 void *data; 1588 uint32_t bucket; 1589 1590 bucket = DYN_BUCKET(hashval, V_curr_dyn_buckets); 1591 DYN_BUCKET_LOCK(bucket); 1592 if (info->direction == MATCH_UNKNOWN || 1593 info->kidx != kidx || 1594 info->hashval != hashval || 1595 info->version != DYN_BUCKET_VERSION(bucket, ipv4_add)) { 1596 /* 1597 * Bucket version has been changed since last lookup, 1598 * do lookup again to be sure that state does not exist. 1599 */ 1600 if (dyn_lookup_ipv4_state_locked(pkt, ulp, pktlen, 1601 bucket, kidx) != 0) { 1602 DYN_BUCKET_UNLOCK(bucket); 1603 return (EEXIST); 1604 } 1605 } 1606 1607 data = dyn_alloc_dyndata(parent, ruleid, rulenum, set, pkt, ulp, 1608 pktlen, hashval, fibnum); 1609 if (data == NULL) { 1610 DYN_BUCKET_UNLOCK(bucket); 1611 return (ENOMEM); 1612 } 1613 1614 s = dyn_alloc_ipv4_state(pkt, kidx, type); 1615 if (s == NULL) { 1616 DYN_BUCKET_UNLOCK(bucket); 1617 uma_zfree(V_dyn_data_zone, data); 1618 return (ENOMEM); 1619 } 1620 1621 s->data = data; 1622 CK_SLIST_INSERT_HEAD(&V_dyn_ipv4[bucket], s, entry); 1623 DYN_COUNT_INC(dyn_count); 1624 DYN_BUCKET_VERSION_BUMP(bucket, ipv4_add); 1625 DYN_BUCKET_UNLOCK(bucket); 1626 return (0); 1627 } 1628 1629 #ifdef INET6 1630 static struct dyn_ipv6_state * 1631 dyn_alloc_ipv6_state(const struct ipfw_flow_id *pkt, uint32_t zoneid, 1632 uint16_t kidx, uint8_t type) 1633 { 1634 struct dyn_ipv6_state *s; 1635 1636 s = uma_zalloc(V_dyn_ipv6_zone, M_NOWAIT | M_ZERO); 1637 if (s == NULL) 1638 return (NULL); 1639 1640 s->type = type; 1641 s->kidx = kidx; 1642 s->zoneid = zoneid; 1643 s->proto = pkt->proto; 1644 s->sport = pkt->src_port; 1645 s->dport = pkt->dst_port; 1646 s->src = pkt->src_ip6; 1647 s->dst = pkt->dst_ip6; 1648 return (s); 1649 } 1650 1651 /* 1652 * Add IPv6 parent state. 1653 * Returns pointer to parent state. When it is not NULL we are in 1654 * critical section and pointer protected by hazard pointer. 1655 * When some error occurs, it return NULL and exit from critical section 1656 * is not needed. 1657 */ 1658 static struct dyn_ipv6_state * 1659 dyn_add_ipv6_parent(void *rule, uint32_t ruleid, uint16_t rulenum, 1660 uint8_t set, const struct ipfw_flow_id *pkt, uint32_t zoneid, 1661 uint32_t hashval, uint32_t version, uint16_t kidx) 1662 { 1663 struct dyn_ipv6_state *s; 1664 struct dyn_parent *limit; 1665 uint32_t bucket; 1666 1667 bucket = DYN_BUCKET(hashval, V_curr_dyn_buckets); 1668 DYN_BUCKET_LOCK(bucket); 1669 if (version != DYN_BUCKET_VERSION(bucket, ipv6_parent_add)) { 1670 /* 1671 * Bucket version has been changed since last lookup, 1672 * do lookup again to be sure that state does not exist. 1673 */ 1674 s = dyn_lookup_ipv6_parent_locked(pkt, zoneid, rule, ruleid, 1675 rulenum, bucket); 1676 if (s != NULL) { 1677 /* 1678 * Simultaneous thread has already created this 1679 * state. Just return it. 1680 */ 1681 DYNSTATE_CRITICAL_ENTER(); 1682 DYNSTATE_PROTECT(s); 1683 DYN_BUCKET_UNLOCK(bucket); 1684 return (s); 1685 } 1686 } 1687 1688 limit = dyn_alloc_parent(rule, ruleid, rulenum, set, hashval); 1689 if (limit == NULL) { 1690 DYN_BUCKET_UNLOCK(bucket); 1691 return (NULL); 1692 } 1693 1694 s = dyn_alloc_ipv6_state(pkt, zoneid, kidx, O_LIMIT_PARENT); 1695 if (s == NULL) { 1696 DYN_BUCKET_UNLOCK(bucket); 1697 uma_zfree(V_dyn_parent_zone, limit); 1698 return (NULL); 1699 } 1700 1701 s->limit = limit; 1702 CK_SLIST_INSERT_HEAD(&V_dyn_ipv6_parent[bucket], s, entry); 1703 DYN_COUNT_INC(dyn_parent_count); 1704 DYN_BUCKET_VERSION_BUMP(bucket, ipv6_parent_add); 1705 DYNSTATE_CRITICAL_ENTER(); 1706 DYNSTATE_PROTECT(s); 1707 DYN_BUCKET_UNLOCK(bucket); 1708 return (s); 1709 } 1710 1711 static int 1712 dyn_add_ipv6_state(void *parent, uint32_t ruleid, uint16_t rulenum, 1713 uint8_t set, const struct ipfw_flow_id *pkt, uint32_t zoneid, 1714 const void *ulp, int pktlen, uint32_t hashval, struct ipfw_dyn_info *info, 1715 uint16_t fibnum, uint16_t kidx, uint8_t type) 1716 { 1717 struct dyn_ipv6_state *s; 1718 struct dyn_data *data; 1719 uint32_t bucket; 1720 1721 bucket = DYN_BUCKET(hashval, V_curr_dyn_buckets); 1722 DYN_BUCKET_LOCK(bucket); 1723 if (info->direction == MATCH_UNKNOWN || 1724 info->kidx != kidx || 1725 info->hashval != hashval || 1726 info->version != DYN_BUCKET_VERSION(bucket, ipv6_add)) { 1727 /* 1728 * Bucket version has been changed since last lookup, 1729 * do lookup again to be sure that state does not exist. 1730 */ 1731 if (dyn_lookup_ipv6_state_locked(pkt, zoneid, ulp, pktlen, 1732 bucket, kidx) != 0) { 1733 DYN_BUCKET_UNLOCK(bucket); 1734 return (EEXIST); 1735 } 1736 } 1737 1738 data = dyn_alloc_dyndata(parent, ruleid, rulenum, set, pkt, ulp, 1739 pktlen, hashval, fibnum); 1740 if (data == NULL) { 1741 DYN_BUCKET_UNLOCK(bucket); 1742 return (ENOMEM); 1743 } 1744 1745 s = dyn_alloc_ipv6_state(pkt, zoneid, kidx, type); 1746 if (s == NULL) { 1747 DYN_BUCKET_UNLOCK(bucket); 1748 uma_zfree(V_dyn_data_zone, data); 1749 return (ENOMEM); 1750 } 1751 1752 s->data = data; 1753 CK_SLIST_INSERT_HEAD(&V_dyn_ipv6[bucket], s, entry); 1754 DYN_COUNT_INC(dyn_count); 1755 DYN_BUCKET_VERSION_BUMP(bucket, ipv6_add); 1756 DYN_BUCKET_UNLOCK(bucket); 1757 return (0); 1758 } 1759 #endif /* INET6 */ 1760 1761 static void * 1762 dyn_get_parent_state(const struct ipfw_flow_id *pkt, uint32_t zoneid, 1763 struct ip_fw *rule, uint32_t hashval, uint32_t limit, uint16_t kidx) 1764 { 1765 char sbuf[24]; 1766 struct dyn_parent *p; 1767 void *ret; 1768 uint32_t bucket, version; 1769 1770 p = NULL; 1771 ret = NULL; 1772 bucket = DYN_BUCKET(hashval, V_curr_dyn_buckets); 1773 DYNSTATE_CRITICAL_ENTER(); 1774 if (IS_IP4_FLOW_ID(pkt)) { 1775 struct dyn_ipv4_state *s; 1776 1777 version = DYN_BUCKET_VERSION(bucket, ipv4_parent_add); 1778 s = dyn_lookup_ipv4_parent(pkt, rule, rule->id, 1779 rule->rulenum, bucket); 1780 if (s == NULL) { 1781 /* 1782 * Exit from critical section because dyn_add_parent() 1783 * will acquire bucket lock. 1784 */ 1785 DYNSTATE_CRITICAL_EXIT(); 1786 1787 s = dyn_add_ipv4_parent(rule, rule->id, 1788 rule->rulenum, rule->set, pkt, hashval, 1789 version, kidx); 1790 if (s == NULL) 1791 return (NULL); 1792 /* Now we are in critical section again. */ 1793 } 1794 ret = s; 1795 p = s->limit; 1796 } 1797 #ifdef INET6 1798 else if (IS_IP6_FLOW_ID(pkt)) { 1799 struct dyn_ipv6_state *s; 1800 1801 version = DYN_BUCKET_VERSION(bucket, ipv6_parent_add); 1802 s = dyn_lookup_ipv6_parent(pkt, zoneid, rule, rule->id, 1803 rule->rulenum, bucket); 1804 if (s == NULL) { 1805 /* 1806 * Exit from critical section because dyn_add_parent() 1807 * can acquire bucket mutex. 1808 */ 1809 DYNSTATE_CRITICAL_EXIT(); 1810 1811 s = dyn_add_ipv6_parent(rule, rule->id, 1812 rule->rulenum, rule->set, pkt, zoneid, hashval, 1813 version, kidx); 1814 if (s == NULL) 1815 return (NULL); 1816 /* Now we are in critical section again. */ 1817 } 1818 ret = s; 1819 p = s->limit; 1820 } 1821 #endif 1822 else { 1823 DYNSTATE_CRITICAL_EXIT(); 1824 return (NULL); 1825 } 1826 1827 /* Check the limit */ 1828 if (DPARENT_COUNT(p) >= limit) { 1829 DYNSTATE_CRITICAL_EXIT(); 1830 if (V_fw_verbose && last_log != time_uptime) { 1831 last_log = time_uptime; 1832 snprintf(sbuf, sizeof(sbuf), "%u drop session", 1833 rule->rulenum); 1834 print_dyn_rule_flags(pkt, O_LIMIT, 1835 LOG_SECURITY | LOG_DEBUG, sbuf, 1836 "too many entries"); 1837 } 1838 return (NULL); 1839 } 1840 1841 /* Take new session into account. */ 1842 DPARENT_COUNT_INC(p); 1843 /* 1844 * We must exit from critical section because the following code 1845 * can acquire bucket mutex. 1846 * We rely on the the 'count' field. The state will not expire 1847 * until it has some child states, i.e. 'count' field is not zero. 1848 * Return state pointer, it will be used by child states as parent. 1849 */ 1850 DYNSTATE_CRITICAL_EXIT(); 1851 return (ret); 1852 } 1853 1854 static int 1855 dyn_install_state(const struct ipfw_flow_id *pkt, uint32_t zoneid, 1856 uint16_t fibnum, const void *ulp, int pktlen, void *rule, 1857 uint32_t ruleid, uint16_t rulenum, uint8_t set, 1858 struct ipfw_dyn_info *info, uint32_t limit, uint16_t limit_mask, 1859 uint16_t kidx, uint8_t type) 1860 { 1861 struct ipfw_flow_id id; 1862 uint32_t hashval, parent_hashval; 1863 int ret; 1864 1865 MPASS(type == O_LIMIT || type == O_KEEP_STATE); 1866 1867 if (type == O_LIMIT) { 1868 /* Create masked flow id and calculate bucket */ 1869 id.addr_type = pkt->addr_type; 1870 id.proto = pkt->proto; 1871 id.fib = fibnum; /* unused */ 1872 id.src_port = (limit_mask & DYN_SRC_PORT) ? 1873 pkt->src_port: 0; 1874 id.dst_port = (limit_mask & DYN_DST_PORT) ? 1875 pkt->dst_port: 0; 1876 if (IS_IP4_FLOW_ID(pkt)) { 1877 id.src_ip = (limit_mask & DYN_SRC_ADDR) ? 1878 pkt->src_ip: 0; 1879 id.dst_ip = (limit_mask & DYN_DST_ADDR) ? 1880 pkt->dst_ip: 0; 1881 } 1882 #ifdef INET6 1883 else if (IS_IP6_FLOW_ID(pkt)) { 1884 if (limit_mask & DYN_SRC_ADDR) 1885 id.src_ip6 = pkt->src_ip6; 1886 else 1887 memset(&id.src_ip6, 0, sizeof(id.src_ip6)); 1888 if (limit_mask & DYN_DST_ADDR) 1889 id.dst_ip6 = pkt->dst_ip6; 1890 else 1891 memset(&id.dst_ip6, 0, sizeof(id.dst_ip6)); 1892 } 1893 #endif 1894 else 1895 return (EAFNOSUPPORT); 1896 1897 parent_hashval = hash_parent(&id, rule); 1898 rule = dyn_get_parent_state(&id, zoneid, rule, parent_hashval, 1899 limit, kidx); 1900 if (rule == NULL) { 1901 #if 0 1902 if (V_fw_verbose && last_log != time_uptime) { 1903 last_log = time_uptime; 1904 snprintf(sbuf, sizeof(sbuf), 1905 "%u drop session", rule->rulenum); 1906 print_dyn_rule_flags(pkt, O_LIMIT, 1907 LOG_SECURITY | LOG_DEBUG, sbuf, 1908 "too many entries"); 1909 } 1910 #endif 1911 return (EACCES); 1912 } 1913 /* 1914 * Limit is not reached, create new state. 1915 * Now rule points to parent state. 1916 */ 1917 } 1918 1919 hashval = hash_packet(pkt); 1920 if (IS_IP4_FLOW_ID(pkt)) 1921 ret = dyn_add_ipv4_state(rule, ruleid, rulenum, set, pkt, 1922 ulp, pktlen, hashval, info, fibnum, kidx, type); 1923 #ifdef INET6 1924 else if (IS_IP6_FLOW_ID(pkt)) 1925 ret = dyn_add_ipv6_state(rule, ruleid, rulenum, set, pkt, 1926 zoneid, ulp, pktlen, hashval, info, fibnum, kidx, type); 1927 #endif /* INET6 */ 1928 else 1929 ret = EAFNOSUPPORT; 1930 1931 if (type == O_LIMIT) { 1932 if (ret != 0) { 1933 /* 1934 * We failed to create child state for O_LIMIT 1935 * opcode. Since we already counted it in the parent, 1936 * we must revert counter back. The 'rule' points to 1937 * parent state, use it to get dyn_parent. 1938 * 1939 * XXXAE: it should be safe to use 'rule' pointer 1940 * without extra lookup, parent state is referenced 1941 * and should not be freed. 1942 */ 1943 if (IS_IP4_FLOW_ID(&id)) 1944 DPARENT_COUNT_DEC( 1945 ((struct dyn_ipv4_state *)rule)->limit); 1946 #ifdef INET6 1947 else if (IS_IP6_FLOW_ID(&id)) 1948 DPARENT_COUNT_DEC( 1949 ((struct dyn_ipv6_state *)rule)->limit); 1950 #endif 1951 } 1952 } 1953 /* 1954 * EEXIST means that simultaneous thread has created this 1955 * state. Consider this as success. 1956 * 1957 * XXXAE: should we invalidate 'info' content here? 1958 */ 1959 if (ret == EEXIST) 1960 return (0); 1961 return (ret); 1962 } 1963 1964 /* 1965 * Install dynamic state. 1966 * chain - ipfw's instance; 1967 * rule - the parent rule that installs the state; 1968 * cmd - opcode that installs the state; 1969 * args - ipfw arguments; 1970 * ulp - upper level protocol header; 1971 * pktlen - packet length; 1972 * info - dynamic state lookup info; 1973 * tablearg - tablearg id. 1974 * 1975 * Returns non-zero value (failure) if state is not installed because 1976 * of errors or because session limitations are enforced. 1977 */ 1978 int 1979 ipfw_dyn_install_state(struct ip_fw_chain *chain, struct ip_fw *rule, 1980 const ipfw_insn_limit *cmd, const struct ip_fw_args *args, 1981 const void *ulp, int pktlen, struct ipfw_dyn_info *info, 1982 uint32_t tablearg) 1983 { 1984 uint32_t limit; 1985 uint16_t limit_mask; 1986 1987 if (cmd->o.opcode == O_LIMIT) { 1988 limit = IP_FW_ARG_TABLEARG(chain, cmd->conn_limit, limit); 1989 limit_mask = cmd->limit_mask; 1990 } else { 1991 limit = 0; 1992 limit_mask = 0; 1993 } 1994 return (dyn_install_state(&args->f_id, 1995 #ifdef INET6 1996 IS_IP6_FLOW_ID(&args->f_id) ? dyn_getscopeid(args): 1997 #endif 1998 0, M_GETFIB(args->m), ulp, pktlen, rule, rule->id, rule->rulenum, 1999 rule->set, info, limit, limit_mask, cmd->o.arg1, cmd->o.opcode)); 2000 } 2001 2002 /* 2003 * Free safe to remove state entries from expired lists. 2004 */ 2005 static void 2006 dyn_free_states(struct ip_fw_chain *chain) 2007 { 2008 struct dyn_ipv4_state *s4, *s4n; 2009 #ifdef INET6 2010 struct dyn_ipv6_state *s6, *s6n; 2011 #endif 2012 int cached_count, i; 2013 2014 /* 2015 * We keep pointers to objects that are in use on each CPU 2016 * in the per-cpu dyn_hp pointer. When object is going to be 2017 * removed, first of it is unlinked from the corresponding 2018 * list. This leads to changing of dyn_bucket_xxx_delver version. 2019 * Unlinked objects is placed into corresponding dyn_expired_xxx 2020 * list. Reader that is going to dereference object pointer checks 2021 * dyn_bucket_xxx_delver version before and after storing pointer 2022 * into dyn_hp. If version is the same, the object is protected 2023 * from freeing and it is safe to dereference. Othervise reader 2024 * tries to iterate list again from the beginning, but this object 2025 * now unlinked and thus will not be accessible. 2026 * 2027 * Copy dyn_hp pointers for each CPU into dyn_hp_cache array. 2028 * It does not matter that some pointer can be changed in 2029 * time while we are copying. We need to check, that objects 2030 * removed in the previous pass are not in use. And if dyn_hp 2031 * pointer does not contain it in the time when we are copying, 2032 * it will not appear there, because it is already unlinked. 2033 * And for new pointers we will not free objects that will be 2034 * unlinked in this pass. 2035 */ 2036 cached_count = 0; 2037 CPU_FOREACH(i) { 2038 dyn_hp_cache[cached_count] = DYNSTATE_GET(i); 2039 if (dyn_hp_cache[cached_count] != NULL) 2040 cached_count++; 2041 } 2042 2043 /* 2044 * Free expired states that are safe to free. 2045 * Check each entry from previous pass in the dyn_expired_xxx 2046 * list, if pointer to the object is in the dyn_hp_cache array, 2047 * keep it until next pass. Otherwise it is safe to free the 2048 * object. 2049 * 2050 * XXXAE: optimize this to use SLIST_REMOVE_AFTER. 2051 */ 2052 #define DYN_FREE_STATES(s, next, name) do { \ 2053 s = SLIST_FIRST(&V_dyn_expired_ ## name); \ 2054 while (s != NULL) { \ 2055 next = SLIST_NEXT(s, expired); \ 2056 for (i = 0; i < cached_count; i++) \ 2057 if (dyn_hp_cache[i] == s) \ 2058 break; \ 2059 if (i == cached_count) { \ 2060 if (s->type == O_LIMIT_PARENT && \ 2061 s->limit->count != 0) { \ 2062 s = next; \ 2063 continue; \ 2064 } \ 2065 SLIST_REMOVE(&V_dyn_expired_ ## name, \ 2066 s, dyn_ ## name ## _state, expired); \ 2067 if (s->type == O_LIMIT_PARENT) \ 2068 uma_zfree(V_dyn_parent_zone, s->limit); \ 2069 else \ 2070 uma_zfree(V_dyn_data_zone, s->data); \ 2071 uma_zfree(V_dyn_ ## name ## _zone, s); \ 2072 } \ 2073 s = next; \ 2074 } \ 2075 } while (0) 2076 2077 /* 2078 * Protect access to expired lists with DYN_EXPIRED_LOCK. 2079 * Userland can invoke ipfw_expire_dyn_states() to delete 2080 * specific states, this will lead to modification of expired 2081 * lists. 2082 * 2083 * XXXAE: do we need DYN_EXPIRED_LOCK? We can just use 2084 * IPFW_UH_WLOCK to protect access to these lists. 2085 */ 2086 DYN_EXPIRED_LOCK(); 2087 DYN_FREE_STATES(s4, s4n, ipv4); 2088 #ifdef INET6 2089 DYN_FREE_STATES(s6, s6n, ipv6); 2090 #endif 2091 DYN_EXPIRED_UNLOCK(); 2092 #undef DYN_FREE_STATES 2093 } 2094 2095 /* 2096 * Returns 1 when state is matched by specified range, otherwise returns 0. 2097 */ 2098 static int 2099 dyn_match_range(uint16_t rulenum, uint8_t set, const ipfw_range_tlv *rt) 2100 { 2101 2102 MPASS(rt != NULL); 2103 /* flush all states */ 2104 if (rt->flags & IPFW_RCFLAG_ALL) 2105 return (1); 2106 if ((rt->flags & IPFW_RCFLAG_SET) != 0 && set != rt->set) 2107 return (0); 2108 if ((rt->flags & IPFW_RCFLAG_RANGE) != 0 && 2109 (rulenum < rt->start_rule || rulenum > rt->end_rule)) 2110 return (0); 2111 return (1); 2112 } 2113 2114 static int 2115 dyn_match_ipv4_state(struct dyn_ipv4_state *s, const ipfw_range_tlv *rt) 2116 { 2117 2118 if (s->type == O_LIMIT_PARENT) 2119 return (dyn_match_range(s->limit->rulenum, 2120 s->limit->set, rt)); 2121 2122 if (s->type == O_LIMIT) 2123 return (dyn_match_range(s->data->rulenum, s->data->set, rt)); 2124 2125 if (V_dyn_keep_states == 0 && 2126 dyn_match_range(s->data->rulenum, s->data->set, rt)) 2127 return (1); 2128 2129 return (0); 2130 } 2131 2132 #ifdef INET6 2133 static int 2134 dyn_match_ipv6_state(struct dyn_ipv6_state *s, const ipfw_range_tlv *rt) 2135 { 2136 2137 if (s->type == O_LIMIT_PARENT) 2138 return (dyn_match_range(s->limit->rulenum, 2139 s->limit->set, rt)); 2140 2141 if (s->type == O_LIMIT) 2142 return (dyn_match_range(s->data->rulenum, s->data->set, rt)); 2143 2144 if (V_dyn_keep_states == 0 && 2145 dyn_match_range(s->data->rulenum, s->data->set, rt)) 2146 return (1); 2147 2148 return (0); 2149 } 2150 #endif 2151 2152 /* 2153 * Unlink expired entries from states lists. 2154 * @rt can be used to specify the range of states for deletion. 2155 */ 2156 static void 2157 dyn_expire_states(struct ip_fw_chain *chain, ipfw_range_tlv *rt) 2158 { 2159 struct dyn_ipv4_slist expired_ipv4; 2160 #ifdef INET6 2161 struct dyn_ipv6_slist expired_ipv6; 2162 struct dyn_ipv6_state *s6, *s6n, *s6p; 2163 #endif 2164 struct dyn_ipv4_state *s4, *s4n, *s4p; 2165 int bucket, removed, length, max_length; 2166 2167 /* 2168 * Unlink expired states from each bucket. 2169 * With acquired bucket lock iterate entries of each lists: 2170 * ipv4, ipv4_parent, ipv6, and ipv6_parent. Check expired time 2171 * and unlink entry from the list, link entry into temporary 2172 * expired_xxx lists then bump "del" bucket version. 2173 * 2174 * When an entry is removed, corresponding states counter is 2175 * decremented. If entry has O_LIMIT type, parent's reference 2176 * counter is decremented. 2177 * 2178 * NOTE: this function can be called from userspace context 2179 * when user deletes rules. In this case all matched states 2180 * will be forcedly unlinked. O_LIMIT_PARENT states will be kept 2181 * in the expired lists until reference counter become zero. 2182 */ 2183 #define DYN_UNLINK_STATES(s, prev, next, exp, af, name, extra) do { \ 2184 length = 0; \ 2185 removed = 0; \ 2186 prev = NULL; \ 2187 s = CK_SLIST_FIRST(&V_dyn_ ## name [bucket]); \ 2188 while (s != NULL) { \ 2189 next = CK_SLIST_NEXT(s, entry); \ 2190 if ((TIME_LEQ((s)->exp, time_uptime) && extra) || \ 2191 (rt != NULL && dyn_match_ ## af ## _state(s, rt))) {\ 2192 if (prev != NULL) \ 2193 CK_SLIST_REMOVE_AFTER(prev, entry); \ 2194 else \ 2195 CK_SLIST_REMOVE_HEAD( \ 2196 &V_dyn_ ## name [bucket], entry); \ 2197 removed++; \ 2198 SLIST_INSERT_HEAD(&expired_ ## af, s, expired); \ 2199 if (s->type == O_LIMIT_PARENT) \ 2200 DYN_COUNT_DEC(dyn_parent_count); \ 2201 else { \ 2202 DYN_COUNT_DEC(dyn_count); \ 2203 if (s->type == O_LIMIT) { \ 2204 s = s->data->parent; \ 2205 DPARENT_COUNT_DEC(s->limit); \ 2206 } \ 2207 } \ 2208 } else { \ 2209 prev = s; \ 2210 length++; \ 2211 } \ 2212 s = next; \ 2213 } \ 2214 if (removed != 0) \ 2215 DYN_BUCKET_VERSION_BUMP(bucket, name ## _del); \ 2216 if (length > max_length) \ 2217 max_length = length; \ 2218 } while (0) 2219 2220 SLIST_INIT(&expired_ipv4); 2221 #ifdef INET6 2222 SLIST_INIT(&expired_ipv6); 2223 #endif 2224 max_length = 0; 2225 for (bucket = 0; bucket < V_curr_dyn_buckets; bucket++) { 2226 DYN_BUCKET_LOCK(bucket); 2227 DYN_UNLINK_STATES(s4, s4p, s4n, data->expire, ipv4, ipv4, 1); 2228 DYN_UNLINK_STATES(s4, s4p, s4n, limit->expire, ipv4, 2229 ipv4_parent, (s4->limit->count == 0)); 2230 #ifdef INET6 2231 DYN_UNLINK_STATES(s6, s6p, s6n, data->expire, ipv6, ipv6, 1); 2232 DYN_UNLINK_STATES(s6, s6p, s6n, limit->expire, ipv6, 2233 ipv6_parent, (s6->limit->count == 0)); 2234 #endif 2235 DYN_BUCKET_UNLOCK(bucket); 2236 } 2237 /* Update curr_max_length for statistics. */ 2238 V_curr_max_length = max_length; 2239 /* 2240 * Concatenate temporary lists with global expired lists. 2241 */ 2242 DYN_EXPIRED_LOCK(); 2243 SLIST_CONCAT(&V_dyn_expired_ipv4, &expired_ipv4, 2244 dyn_ipv4_state, expired); 2245 #ifdef INET6 2246 SLIST_CONCAT(&V_dyn_expired_ipv6, &expired_ipv6, 2247 dyn_ipv6_state, expired); 2248 #endif 2249 DYN_EXPIRED_UNLOCK(); 2250 #undef DYN_UNLINK_STATES 2251 #undef DYN_UNREF_STATES 2252 } 2253 2254 static struct mbuf * 2255 dyn_mgethdr(int len, uint16_t fibnum) 2256 { 2257 struct mbuf *m; 2258 2259 m = m_gethdr(M_NOWAIT, MT_DATA); 2260 if (m == NULL) 2261 return (NULL); 2262 #ifdef MAC 2263 mac_netinet_firewall_send(m); 2264 #endif 2265 M_SETFIB(m, fibnum); 2266 m->m_data += max_linkhdr; 2267 m->m_flags |= M_SKIP_FIREWALL; 2268 m->m_len = m->m_pkthdr.len = len; 2269 bzero(m->m_data, len); 2270 return (m); 2271 } 2272 2273 static void 2274 dyn_make_keepalive_ipv4(struct mbuf *m, in_addr_t src, in_addr_t dst, 2275 uint32_t seq, uint32_t ack, uint16_t sport, uint16_t dport) 2276 { 2277 struct tcphdr *tcp; 2278 struct ip *ip; 2279 2280 ip = mtod(m, struct ip *); 2281 ip->ip_v = 4; 2282 ip->ip_hl = sizeof(*ip) >> 2; 2283 ip->ip_tos = IPTOS_LOWDELAY; 2284 ip->ip_len = htons(m->m_len); 2285 ip->ip_off |= htons(IP_DF); 2286 ip->ip_ttl = V_ip_defttl; 2287 ip->ip_p = IPPROTO_TCP; 2288 ip->ip_src.s_addr = htonl(src); 2289 ip->ip_dst.s_addr = htonl(dst); 2290 2291 tcp = mtodo(m, sizeof(struct ip)); 2292 tcp->th_sport = htons(sport); 2293 tcp->th_dport = htons(dport); 2294 tcp->th_off = sizeof(struct tcphdr) >> 2; 2295 tcp->th_seq = htonl(seq); 2296 tcp->th_ack = htonl(ack); 2297 tcp->th_flags = TH_ACK; 2298 tcp->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2299 htons(sizeof(struct tcphdr) + IPPROTO_TCP)); 2300 2301 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2302 m->m_pkthdr.csum_flags = CSUM_TCP; 2303 } 2304 2305 static void 2306 dyn_enqueue_keepalive_ipv4(struct mbufq *q, const struct dyn_ipv4_state *s) 2307 { 2308 struct mbuf *m; 2309 2310 if ((s->data->state & ACK_FWD) == 0 && s->data->ack_fwd > 0) { 2311 m = dyn_mgethdr(sizeof(struct ip) + sizeof(struct tcphdr), 2312 s->data->fibnum); 2313 if (m != NULL) { 2314 dyn_make_keepalive_ipv4(m, s->dst, s->src, 2315 s->data->ack_fwd - 1, s->data->ack_rev, 2316 s->dport, s->sport); 2317 if (mbufq_enqueue(q, m)) { 2318 m_freem(m); 2319 log(LOG_DEBUG, "ipfw: limit for IPv4 " 2320 "keepalive queue is reached.\n"); 2321 return; 2322 } 2323 } 2324 } 2325 2326 if ((s->data->state & ACK_REV) == 0 && s->data->ack_rev > 0) { 2327 m = dyn_mgethdr(sizeof(struct ip) + sizeof(struct tcphdr), 2328 s->data->fibnum); 2329 if (m != NULL) { 2330 dyn_make_keepalive_ipv4(m, s->src, s->dst, 2331 s->data->ack_rev - 1, s->data->ack_fwd, 2332 s->sport, s->dport); 2333 if (mbufq_enqueue(q, m)) { 2334 m_freem(m); 2335 log(LOG_DEBUG, "ipfw: limit for IPv4 " 2336 "keepalive queue is reached.\n"); 2337 return; 2338 } 2339 } 2340 } 2341 } 2342 2343 /* 2344 * Prepare and send keep-alive packets. 2345 */ 2346 static void 2347 dyn_send_keepalive_ipv4(struct ip_fw_chain *chain) 2348 { 2349 struct mbufq q; 2350 struct mbuf *m; 2351 struct dyn_ipv4_state *s; 2352 uint32_t bucket; 2353 2354 mbufq_init(&q, DYN_KEEPALIVE_MAXQ); 2355 IPFW_UH_RLOCK(chain); 2356 /* 2357 * It is safe to not use hazard pointer and just do lockless 2358 * access to the lists, because states entries can not be deleted 2359 * while we hold IPFW_UH_RLOCK. 2360 */ 2361 for (bucket = 0; bucket < V_curr_dyn_buckets; bucket++) { 2362 CK_SLIST_FOREACH(s, &V_dyn_ipv4[bucket], entry) { 2363 /* 2364 * Only established TCP connections that will 2365 * become expired withing dyn_keepalive_interval. 2366 */ 2367 if (s->proto != IPPROTO_TCP || 2368 (s->data->state & BOTH_SYN) != BOTH_SYN || 2369 TIME_LEQ(time_uptime + V_dyn_keepalive_interval, 2370 s->data->expire)) 2371 continue; 2372 dyn_enqueue_keepalive_ipv4(&q, s); 2373 } 2374 } 2375 IPFW_UH_RUNLOCK(chain); 2376 while ((m = mbufq_dequeue(&q)) != NULL) 2377 ip_output(m, NULL, NULL, 0, NULL, NULL); 2378 } 2379 2380 #ifdef INET6 2381 static void 2382 dyn_make_keepalive_ipv6(struct mbuf *m, const struct in6_addr *src, 2383 const struct in6_addr *dst, uint32_t zoneid, uint32_t seq, uint32_t ack, 2384 uint16_t sport, uint16_t dport) 2385 { 2386 struct tcphdr *tcp; 2387 struct ip6_hdr *ip6; 2388 2389 ip6 = mtod(m, struct ip6_hdr *); 2390 ip6->ip6_vfc |= IPV6_VERSION; 2391 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 2392 ip6->ip6_nxt = IPPROTO_TCP; 2393 ip6->ip6_hlim = IPV6_DEFHLIM; 2394 ip6->ip6_src = *src; 2395 if (IN6_IS_ADDR_LINKLOCAL(src)) 2396 ip6->ip6_src.s6_addr16[1] = htons(zoneid & 0xffff); 2397 ip6->ip6_dst = *dst; 2398 if (IN6_IS_ADDR_LINKLOCAL(dst)) 2399 ip6->ip6_dst.s6_addr16[1] = htons(zoneid & 0xffff); 2400 2401 tcp = mtodo(m, sizeof(struct ip6_hdr)); 2402 tcp->th_sport = htons(sport); 2403 tcp->th_dport = htons(dport); 2404 tcp->th_off = sizeof(struct tcphdr) >> 2; 2405 tcp->th_seq = htonl(seq); 2406 tcp->th_ack = htonl(ack); 2407 tcp->th_flags = TH_ACK; 2408 tcp->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr), 2409 IPPROTO_TCP, 0); 2410 2411 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2412 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2413 } 2414 2415 static void 2416 dyn_enqueue_keepalive_ipv6(struct mbufq *q, const struct dyn_ipv6_state *s) 2417 { 2418 struct mbuf *m; 2419 2420 if ((s->data->state & ACK_FWD) == 0 && s->data->ack_fwd > 0) { 2421 m = dyn_mgethdr(sizeof(struct ip6_hdr) + 2422 sizeof(struct tcphdr), s->data->fibnum); 2423 if (m != NULL) { 2424 dyn_make_keepalive_ipv6(m, &s->dst, &s->src, 2425 s->zoneid, s->data->ack_fwd - 1, s->data->ack_rev, 2426 s->dport, s->sport); 2427 if (mbufq_enqueue(q, m)) { 2428 m_freem(m); 2429 log(LOG_DEBUG, "ipfw: limit for IPv6 " 2430 "keepalive queue is reached.\n"); 2431 return; 2432 } 2433 } 2434 } 2435 2436 if ((s->data->state & ACK_REV) == 0 && s->data->ack_rev > 0) { 2437 m = dyn_mgethdr(sizeof(struct ip6_hdr) + 2438 sizeof(struct tcphdr), s->data->fibnum); 2439 if (m != NULL) { 2440 dyn_make_keepalive_ipv6(m, &s->src, &s->dst, 2441 s->zoneid, s->data->ack_rev - 1, s->data->ack_fwd, 2442 s->sport, s->dport); 2443 if (mbufq_enqueue(q, m)) { 2444 m_freem(m); 2445 log(LOG_DEBUG, "ipfw: limit for IPv6 " 2446 "keepalive queue is reached.\n"); 2447 return; 2448 } 2449 } 2450 } 2451 } 2452 2453 static void 2454 dyn_send_keepalive_ipv6(struct ip_fw_chain *chain) 2455 { 2456 struct mbufq q; 2457 struct mbuf *m; 2458 struct dyn_ipv6_state *s; 2459 uint32_t bucket; 2460 2461 mbufq_init(&q, DYN_KEEPALIVE_MAXQ); 2462 IPFW_UH_RLOCK(chain); 2463 /* 2464 * It is safe to not use hazard pointer and just do lockless 2465 * access to the lists, because states entries can not be deleted 2466 * while we hold IPFW_UH_RLOCK. 2467 */ 2468 for (bucket = 0; bucket < V_curr_dyn_buckets; bucket++) { 2469 CK_SLIST_FOREACH(s, &V_dyn_ipv6[bucket], entry) { 2470 /* 2471 * Only established TCP connections that will 2472 * become expired withing dyn_keepalive_interval. 2473 */ 2474 if (s->proto != IPPROTO_TCP || 2475 (s->data->state & BOTH_SYN) != BOTH_SYN || 2476 TIME_LEQ(time_uptime + V_dyn_keepalive_interval, 2477 s->data->expire)) 2478 continue; 2479 dyn_enqueue_keepalive_ipv6(&q, s); 2480 } 2481 } 2482 IPFW_UH_RUNLOCK(chain); 2483 while ((m = mbufq_dequeue(&q)) != NULL) 2484 ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 2485 } 2486 #endif /* INET6 */ 2487 2488 static void 2489 dyn_grow_hashtable(struct ip_fw_chain *chain, uint32_t new) 2490 { 2491 #ifdef INET6 2492 struct dyn_ipv6ck_slist *ipv6, *ipv6_parent; 2493 uint32_t *ipv6_add, *ipv6_del, *ipv6_parent_add, *ipv6_parent_del; 2494 struct dyn_ipv6_state *s6; 2495 #endif 2496 struct dyn_ipv4ck_slist *ipv4, *ipv4_parent; 2497 uint32_t *ipv4_add, *ipv4_del, *ipv4_parent_add, *ipv4_parent_del; 2498 struct dyn_ipv4_state *s4; 2499 struct mtx *bucket_lock; 2500 void *tmp; 2501 uint32_t bucket; 2502 2503 MPASS(powerof2(new)); 2504 DYN_DEBUG("grow hash size %u -> %u", V_curr_dyn_buckets, new); 2505 /* 2506 * Allocate and initialize new lists. 2507 * XXXAE: on memory pressure this can disable callout timer. 2508 */ 2509 bucket_lock = malloc(new * sizeof(struct mtx), M_IPFW, 2510 M_WAITOK | M_ZERO); 2511 ipv4 = malloc(new * sizeof(struct dyn_ipv4ck_slist), M_IPFW, 2512 M_WAITOK | M_ZERO); 2513 ipv4_parent = malloc(new * sizeof(struct dyn_ipv4ck_slist), M_IPFW, 2514 M_WAITOK | M_ZERO); 2515 ipv4_add = malloc(new * sizeof(uint32_t), M_IPFW, M_WAITOK | M_ZERO); 2516 ipv4_del = malloc(new * sizeof(uint32_t), M_IPFW, M_WAITOK | M_ZERO); 2517 ipv4_parent_add = malloc(new * sizeof(uint32_t), M_IPFW, 2518 M_WAITOK | M_ZERO); 2519 ipv4_parent_del = malloc(new * sizeof(uint32_t), M_IPFW, 2520 M_WAITOK | M_ZERO); 2521 #ifdef INET6 2522 ipv6 = malloc(new * sizeof(struct dyn_ipv6ck_slist), M_IPFW, 2523 M_WAITOK | M_ZERO); 2524 ipv6_parent = malloc(new * sizeof(struct dyn_ipv6ck_slist), M_IPFW, 2525 M_WAITOK | M_ZERO); 2526 ipv6_add = malloc(new * sizeof(uint32_t), M_IPFW, M_WAITOK | M_ZERO); 2527 ipv6_del = malloc(new * sizeof(uint32_t), M_IPFW, M_WAITOK | M_ZERO); 2528 ipv6_parent_add = malloc(new * sizeof(uint32_t), M_IPFW, 2529 M_WAITOK | M_ZERO); 2530 ipv6_parent_del = malloc(new * sizeof(uint32_t), M_IPFW, 2531 M_WAITOK | M_ZERO); 2532 #endif 2533 for (bucket = 0; bucket < new; bucket++) { 2534 DYN_BUCKET_LOCK_INIT(bucket_lock, bucket); 2535 CK_SLIST_INIT(&ipv4[bucket]); 2536 CK_SLIST_INIT(&ipv4_parent[bucket]); 2537 #ifdef INET6 2538 CK_SLIST_INIT(&ipv6[bucket]); 2539 CK_SLIST_INIT(&ipv6_parent[bucket]); 2540 #endif 2541 } 2542 2543 #define DYN_RELINK_STATES(s, hval, i, head, ohead) do { \ 2544 while ((s = CK_SLIST_FIRST(&V_dyn_ ## ohead[i])) != NULL) { \ 2545 CK_SLIST_REMOVE_HEAD(&V_dyn_ ## ohead[i], entry); \ 2546 CK_SLIST_INSERT_HEAD(&head[DYN_BUCKET(s->hval, new)], \ 2547 s, entry); \ 2548 } \ 2549 } while (0) 2550 /* 2551 * Prevent rules changing from userland. 2552 */ 2553 IPFW_UH_WLOCK(chain); 2554 /* 2555 * Hold traffic processing until we finish resize to 2556 * prevent access to states lists. 2557 */ 2558 IPFW_WLOCK(chain); 2559 /* Re-link all dynamic states */ 2560 for (bucket = 0; bucket < V_curr_dyn_buckets; bucket++) { 2561 DYN_RELINK_STATES(s4, data->hashval, bucket, ipv4, ipv4); 2562 DYN_RELINK_STATES(s4, limit->hashval, bucket, ipv4_parent, 2563 ipv4_parent); 2564 #ifdef INET6 2565 DYN_RELINK_STATES(s6, data->hashval, bucket, ipv6, ipv6); 2566 DYN_RELINK_STATES(s6, limit->hashval, bucket, ipv6_parent, 2567 ipv6_parent); 2568 #endif 2569 } 2570 2571 #define DYN_SWAP_PTR(old, new, tmp) do { \ 2572 tmp = old; \ 2573 old = new; \ 2574 new = tmp; \ 2575 } while (0) 2576 /* Swap pointers */ 2577 DYN_SWAP_PTR(V_dyn_bucket_lock, bucket_lock, tmp); 2578 DYN_SWAP_PTR(V_dyn_ipv4, ipv4, tmp); 2579 DYN_SWAP_PTR(V_dyn_ipv4_parent, ipv4_parent, tmp); 2580 DYN_SWAP_PTR(V_dyn_ipv4_add, ipv4_add, tmp); 2581 DYN_SWAP_PTR(V_dyn_ipv4_parent_add, ipv4_parent_add, tmp); 2582 DYN_SWAP_PTR(V_dyn_ipv4_del, ipv4_del, tmp); 2583 DYN_SWAP_PTR(V_dyn_ipv4_parent_del, ipv4_parent_del, tmp); 2584 2585 #ifdef INET6 2586 DYN_SWAP_PTR(V_dyn_ipv6, ipv6, tmp); 2587 DYN_SWAP_PTR(V_dyn_ipv6_parent, ipv6_parent, tmp); 2588 DYN_SWAP_PTR(V_dyn_ipv6_add, ipv6_add, tmp); 2589 DYN_SWAP_PTR(V_dyn_ipv6_parent_add, ipv6_parent_add, tmp); 2590 DYN_SWAP_PTR(V_dyn_ipv6_del, ipv6_del, tmp); 2591 DYN_SWAP_PTR(V_dyn_ipv6_parent_del, ipv6_parent_del, tmp); 2592 #endif 2593 bucket = V_curr_dyn_buckets; 2594 V_curr_dyn_buckets = new; 2595 2596 IPFW_WUNLOCK(chain); 2597 IPFW_UH_WUNLOCK(chain); 2598 2599 /* Release old resources */ 2600 while (bucket-- != 0) 2601 DYN_BUCKET_LOCK_DESTROY(bucket_lock, bucket); 2602 free(bucket_lock, M_IPFW); 2603 free(ipv4, M_IPFW); 2604 free(ipv4_parent, M_IPFW); 2605 free(ipv4_add, M_IPFW); 2606 free(ipv4_parent_add, M_IPFW); 2607 free(ipv4_del, M_IPFW); 2608 free(ipv4_parent_del, M_IPFW); 2609 #ifdef INET6 2610 free(ipv6, M_IPFW); 2611 free(ipv6_parent, M_IPFW); 2612 free(ipv6_add, M_IPFW); 2613 free(ipv6_parent_add, M_IPFW); 2614 free(ipv6_del, M_IPFW); 2615 free(ipv6_parent_del, M_IPFW); 2616 #endif 2617 } 2618 2619 /* 2620 * This function is used to perform various maintenance 2621 * on dynamic hash lists. Currently it is called every second. 2622 */ 2623 static void 2624 dyn_tick(void *vnetx) 2625 { 2626 uint32_t buckets; 2627 2628 CURVNET_SET((struct vnet *)vnetx); 2629 /* 2630 * First free states unlinked in previous passes. 2631 */ 2632 dyn_free_states(&V_layer3_chain); 2633 /* 2634 * Now unlink others expired states. 2635 * We use IPFW_UH_WLOCK to avoid concurrent call of 2636 * dyn_expire_states(). It is the only function that does 2637 * deletion of state entries from states lists. 2638 */ 2639 IPFW_UH_WLOCK(&V_layer3_chain); 2640 dyn_expire_states(&V_layer3_chain, NULL); 2641 IPFW_UH_WUNLOCK(&V_layer3_chain); 2642 /* 2643 * Send keepalives if they are enabled and the time has come. 2644 */ 2645 if (V_dyn_keepalive != 0 && 2646 V_dyn_keepalive_last + V_dyn_keepalive_period <= time_uptime) { 2647 V_dyn_keepalive_last = time_uptime; 2648 dyn_send_keepalive_ipv4(&V_layer3_chain); 2649 #ifdef INET6 2650 dyn_send_keepalive_ipv6(&V_layer3_chain); 2651 #endif 2652 } 2653 /* 2654 * Check if we need to resize the hash: 2655 * if current number of states exceeds number of buckets in hash, 2656 * and dyn_buckets_max permits to grow the number of buckets, then 2657 * do it. Grow hash size to the minimum power of 2 which is bigger 2658 * than current states count. 2659 */ 2660 if (V_curr_dyn_buckets < V_dyn_buckets_max && 2661 (V_curr_dyn_buckets < V_dyn_count / 2 || ( 2662 V_curr_dyn_buckets < V_dyn_count && V_curr_max_length > 8))) { 2663 buckets = 1 << fls(V_dyn_count); 2664 if (buckets > V_dyn_buckets_max) 2665 buckets = V_dyn_buckets_max; 2666 dyn_grow_hashtable(&V_layer3_chain, buckets); 2667 } 2668 2669 callout_reset_on(&V_dyn_timeout, hz, dyn_tick, vnetx, 0); 2670 CURVNET_RESTORE(); 2671 } 2672 2673 void 2674 ipfw_expire_dyn_states(struct ip_fw_chain *chain, ipfw_range_tlv *rt) 2675 { 2676 /* 2677 * Do not perform any checks if we currently have no dynamic states 2678 */ 2679 if (V_dyn_count == 0) 2680 return; 2681 2682 IPFW_UH_WLOCK_ASSERT(chain); 2683 dyn_expire_states(chain, rt); 2684 } 2685 2686 /* 2687 * Returns size of dynamic states in legacy format 2688 */ 2689 int 2690 ipfw_dyn_len(void) 2691 { 2692 2693 return ((V_dyn_count + V_dyn_parent_count) * sizeof(ipfw_dyn_rule)); 2694 } 2695 2696 /* 2697 * Returns number of dynamic states. 2698 * Used by dump format v1 (current). 2699 */ 2700 uint32_t 2701 ipfw_dyn_get_count(void) 2702 { 2703 2704 return (V_dyn_count + V_dyn_parent_count); 2705 } 2706 2707 /* 2708 * Check if rule contains at least one dynamic opcode. 2709 * 2710 * Returns 1 if such opcode is found, 0 otherwise. 2711 */ 2712 int 2713 ipfw_is_dyn_rule(struct ip_fw *rule) 2714 { 2715 int cmdlen, l; 2716 ipfw_insn *cmd; 2717 2718 l = rule->cmd_len; 2719 cmd = rule->cmd; 2720 cmdlen = 0; 2721 for ( ; l > 0 ; l -= cmdlen, cmd += cmdlen) { 2722 cmdlen = F_LEN(cmd); 2723 2724 switch (cmd->opcode) { 2725 case O_LIMIT: 2726 case O_KEEP_STATE: 2727 case O_PROBE_STATE: 2728 case O_CHECK_STATE: 2729 return (1); 2730 } 2731 } 2732 2733 return (0); 2734 } 2735 2736 static void 2737 dyn_export_parent(const struct dyn_parent *p, uint16_t kidx, 2738 ipfw_dyn_rule *dst) 2739 { 2740 2741 dst->dyn_type = O_LIMIT_PARENT; 2742 dst->kidx = kidx; 2743 dst->count = (uint16_t)DPARENT_COUNT(p); 2744 dst->expire = TIME_LEQ(p->expire, time_uptime) ? 0: 2745 p->expire - time_uptime; 2746 2747 /* 'rule' is used to pass up the rule number and set */ 2748 memcpy(&dst->rule, &p->rulenum, sizeof(p->rulenum)); 2749 /* store set number into high word of dst->rule pointer. */ 2750 memcpy((char *)&dst->rule + sizeof(p->rulenum), &p->set, 2751 sizeof(p->set)); 2752 2753 /* unused fields */ 2754 dst->pcnt = 0; 2755 dst->bcnt = 0; 2756 dst->parent = NULL; 2757 dst->state = 0; 2758 dst->ack_fwd = 0; 2759 dst->ack_rev = 0; 2760 dst->bucket = p->hashval; 2761 /* 2762 * The legacy userland code will interpret a NULL here as a marker 2763 * for the last dynamic rule. 2764 */ 2765 dst->next = (ipfw_dyn_rule *)1; 2766 } 2767 2768 static void 2769 dyn_export_data(const struct dyn_data *data, uint16_t kidx, uint8_t type, 2770 ipfw_dyn_rule *dst) 2771 { 2772 2773 dst->dyn_type = type; 2774 dst->kidx = kidx; 2775 dst->pcnt = data->pcnt_fwd + data->pcnt_rev; 2776 dst->bcnt = data->bcnt_fwd + data->bcnt_rev; 2777 dst->expire = TIME_LEQ(data->expire, time_uptime) ? 0: 2778 data->expire - time_uptime; 2779 2780 /* 'rule' is used to pass up the rule number and set */ 2781 memcpy(&dst->rule, &data->rulenum, sizeof(data->rulenum)); 2782 /* store set number into high word of dst->rule pointer. */ 2783 memcpy((char *)&dst->rule + sizeof(data->rulenum), &data->set, 2784 sizeof(data->set)); 2785 2786 /* unused fields */ 2787 dst->parent = NULL; 2788 dst->state = data->state; 2789 dst->ack_fwd = data->ack_fwd; 2790 dst->ack_rev = data->ack_rev; 2791 dst->count = 0; 2792 dst->bucket = data->hashval; 2793 /* 2794 * The legacy userland code will interpret a NULL here as a marker 2795 * for the last dynamic rule. 2796 */ 2797 dst->next = (ipfw_dyn_rule *)1; 2798 } 2799 2800 static void 2801 dyn_export_ipv4_state(const struct dyn_ipv4_state *s, ipfw_dyn_rule *dst) 2802 { 2803 2804 switch (s->type) { 2805 case O_LIMIT_PARENT: 2806 dyn_export_parent(s->limit, s->kidx, dst); 2807 break; 2808 default: 2809 dyn_export_data(s->data, s->kidx, s->type, dst); 2810 } 2811 2812 dst->id.dst_ip = s->dst; 2813 dst->id.src_ip = s->src; 2814 dst->id.dst_port = s->dport; 2815 dst->id.src_port = s->sport; 2816 dst->id.fib = s->data->fibnum; 2817 dst->id.proto = s->proto; 2818 dst->id._flags = 0; 2819 dst->id.addr_type = 4; 2820 2821 memset(&dst->id.dst_ip6, 0, sizeof(dst->id.dst_ip6)); 2822 memset(&dst->id.src_ip6, 0, sizeof(dst->id.src_ip6)); 2823 dst->id.flow_id6 = dst->id.extra = 0; 2824 } 2825 2826 #ifdef INET6 2827 static void 2828 dyn_export_ipv6_state(const struct dyn_ipv6_state *s, ipfw_dyn_rule *dst) 2829 { 2830 2831 switch (s->type) { 2832 case O_LIMIT_PARENT: 2833 dyn_export_parent(s->limit, s->kidx, dst); 2834 break; 2835 default: 2836 dyn_export_data(s->data, s->kidx, s->type, dst); 2837 } 2838 2839 dst->id.src_ip6 = s->src; 2840 dst->id.dst_ip6 = s->dst; 2841 dst->id.dst_port = s->dport; 2842 dst->id.src_port = s->sport; 2843 dst->id.fib = s->data->fibnum; 2844 dst->id.proto = s->proto; 2845 dst->id._flags = 0; 2846 dst->id.addr_type = 6; 2847 2848 dst->id.dst_ip = dst->id.src_ip = 0; 2849 dst->id.flow_id6 = dst->id.extra = 0; 2850 } 2851 #endif /* INET6 */ 2852 2853 /* 2854 * Fills the buffer given by @sd with dynamic states. 2855 * Used by dump format v1 (current). 2856 * 2857 * Returns 0 on success. 2858 */ 2859 int 2860 ipfw_dump_states(struct ip_fw_chain *chain, struct sockopt_data *sd) 2861 { 2862 #ifdef INET6 2863 struct dyn_ipv6_state *s6; 2864 #endif 2865 struct dyn_ipv4_state *s4; 2866 ipfw_obj_dyntlv *dst, *last; 2867 ipfw_obj_ctlv *ctlv; 2868 uint32_t bucket; 2869 2870 if (V_dyn_count == 0) 2871 return (0); 2872 2873 /* 2874 * IPFW_UH_RLOCK garantees that another userland request 2875 * and callout thread will not delete entries from states 2876 * lists. 2877 */ 2878 IPFW_UH_RLOCK_ASSERT(chain); 2879 2880 ctlv = (ipfw_obj_ctlv *)ipfw_get_sopt_space(sd, sizeof(*ctlv)); 2881 if (ctlv == NULL) 2882 return (ENOMEM); 2883 ctlv->head.type = IPFW_TLV_DYNSTATE_LIST; 2884 ctlv->objsize = sizeof(ipfw_obj_dyntlv); 2885 last = NULL; 2886 2887 #define DYN_EXPORT_STATES(s, af, h, b) \ 2888 CK_SLIST_FOREACH(s, &V_dyn_ ## h[b], entry) { \ 2889 dst = (ipfw_obj_dyntlv *)ipfw_get_sopt_space(sd, \ 2890 sizeof(ipfw_obj_dyntlv)); \ 2891 if (dst == NULL) \ 2892 return (ENOMEM); \ 2893 dyn_export_ ## af ## _state(s, &dst->state); \ 2894 dst->head.length = sizeof(ipfw_obj_dyntlv); \ 2895 dst->head.type = IPFW_TLV_DYN_ENT; \ 2896 last = dst; \ 2897 } 2898 2899 for (bucket = 0; bucket < V_curr_dyn_buckets; bucket++) { 2900 DYN_EXPORT_STATES(s4, ipv4, ipv4_parent, bucket); 2901 DYN_EXPORT_STATES(s4, ipv4, ipv4, bucket); 2902 #ifdef INET6 2903 DYN_EXPORT_STATES(s6, ipv6, ipv6_parent, bucket); 2904 DYN_EXPORT_STATES(s6, ipv6, ipv6, bucket); 2905 #endif /* INET6 */ 2906 } 2907 2908 /* mark last dynamic rule */ 2909 if (last != NULL) 2910 last->head.flags = IPFW_DF_LAST; /* XXX: unused */ 2911 return (0); 2912 #undef DYN_EXPORT_STATES 2913 } 2914 2915 /* 2916 * Fill given buffer with dynamic states (legacy format). 2917 * IPFW_UH_RLOCK has to be held while calling. 2918 */ 2919 void 2920 ipfw_get_dynamic(struct ip_fw_chain *chain, char **pbp, const char *ep) 2921 { 2922 #ifdef INET6 2923 struct dyn_ipv6_state *s6; 2924 #endif 2925 struct dyn_ipv4_state *s4; 2926 ipfw_dyn_rule *p, *last = NULL; 2927 char *bp; 2928 uint32_t bucket; 2929 2930 if (V_dyn_count == 0) 2931 return; 2932 bp = *pbp; 2933 2934 IPFW_UH_RLOCK_ASSERT(chain); 2935 2936 #define DYN_EXPORT_STATES(s, af, head, b) \ 2937 CK_SLIST_FOREACH(s, &V_dyn_ ## head[b], entry) { \ 2938 if (bp + sizeof(*p) > ep) \ 2939 break; \ 2940 p = (ipfw_dyn_rule *)bp; \ 2941 dyn_export_ ## af ## _state(s, p); \ 2942 last = p; \ 2943 bp += sizeof(*p); \ 2944 } 2945 2946 for (bucket = 0; bucket < V_curr_dyn_buckets; bucket++) { 2947 DYN_EXPORT_STATES(s4, ipv4, ipv4_parent, bucket); 2948 DYN_EXPORT_STATES(s4, ipv4, ipv4, bucket); 2949 #ifdef INET6 2950 DYN_EXPORT_STATES(s6, ipv6, ipv6_parent, bucket); 2951 DYN_EXPORT_STATES(s6, ipv6, ipv6, bucket); 2952 #endif /* INET6 */ 2953 } 2954 2955 if (last != NULL) /* mark last dynamic rule */ 2956 last->next = NULL; 2957 *pbp = bp; 2958 #undef DYN_EXPORT_STATES 2959 } 2960 2961 void 2962 ipfw_dyn_init(struct ip_fw_chain *chain) 2963 { 2964 2965 #ifdef IPFIREWALL_JENKINSHASH 2966 V_dyn_hashseed = arc4random(); 2967 #endif 2968 V_dyn_max = 16384; /* max # of states */ 2969 V_dyn_parent_max = 4096; /* max # of parent states */ 2970 V_dyn_buckets_max = 8192; /* must be power of 2 */ 2971 2972 V_dyn_ack_lifetime = 300; 2973 V_dyn_syn_lifetime = 20; 2974 V_dyn_fin_lifetime = 1; 2975 V_dyn_rst_lifetime = 1; 2976 V_dyn_udp_lifetime = 10; 2977 V_dyn_short_lifetime = 5; 2978 2979 V_dyn_keepalive_interval = 20; 2980 V_dyn_keepalive_period = 5; 2981 V_dyn_keepalive = 1; /* send keepalives */ 2982 V_dyn_keepalive_last = time_uptime; 2983 2984 V_dyn_data_zone = uma_zcreate("IPFW dynamic states data", 2985 sizeof(struct dyn_data), NULL, NULL, NULL, NULL, 2986 UMA_ALIGN_PTR, 0); 2987 uma_zone_set_max(V_dyn_data_zone, V_dyn_max); 2988 2989 V_dyn_parent_zone = uma_zcreate("IPFW parent dynamic states", 2990 sizeof(struct dyn_parent), NULL, NULL, NULL, NULL, 2991 UMA_ALIGN_PTR, 0); 2992 uma_zone_set_max(V_dyn_parent_zone, V_dyn_parent_max); 2993 2994 SLIST_INIT(&V_dyn_expired_ipv4); 2995 V_dyn_ipv4 = NULL; 2996 V_dyn_ipv4_parent = NULL; 2997 V_dyn_ipv4_zone = uma_zcreate("IPFW IPv4 dynamic states", 2998 sizeof(struct dyn_ipv4_state), NULL, NULL, NULL, NULL, 2999 UMA_ALIGN_PTR, 0); 3000 3001 #ifdef INET6 3002 SLIST_INIT(&V_dyn_expired_ipv6); 3003 V_dyn_ipv6 = NULL; 3004 V_dyn_ipv6_parent = NULL; 3005 V_dyn_ipv6_zone = uma_zcreate("IPFW IPv6 dynamic states", 3006 sizeof(struct dyn_ipv6_state), NULL, NULL, NULL, NULL, 3007 UMA_ALIGN_PTR, 0); 3008 #endif 3009 3010 /* Initialize buckets. */ 3011 V_curr_dyn_buckets = 0; 3012 V_dyn_bucket_lock = NULL; 3013 dyn_grow_hashtable(chain, 256); 3014 3015 if (IS_DEFAULT_VNET(curvnet)) 3016 dyn_hp_cache = malloc(mp_ncpus * sizeof(void *), M_IPFW, 3017 M_WAITOK | M_ZERO); 3018 3019 DYN_EXPIRED_LOCK_INIT(); 3020 callout_init(&V_dyn_timeout, 1); 3021 callout_reset(&V_dyn_timeout, hz, dyn_tick, curvnet); 3022 IPFW_ADD_OBJ_REWRITER(IS_DEFAULT_VNET(curvnet), dyn_opcodes); 3023 } 3024 3025 void 3026 ipfw_dyn_uninit(int pass) 3027 { 3028 #ifdef INET6 3029 struct dyn_ipv6_state *s6; 3030 #endif 3031 struct dyn_ipv4_state *s4; 3032 int bucket; 3033 3034 if (pass == 0) { 3035 callout_drain(&V_dyn_timeout); 3036 return; 3037 } 3038 IPFW_DEL_OBJ_REWRITER(IS_DEFAULT_VNET(curvnet), dyn_opcodes); 3039 DYN_EXPIRED_LOCK_DESTROY(); 3040 3041 #define DYN_FREE_STATES_FORCED(CK, s, af, name, en) do { \ 3042 while ((s = CK ## SLIST_FIRST(&V_dyn_ ## name)) != NULL) { \ 3043 CK ## SLIST_REMOVE_HEAD(&V_dyn_ ## name, en); \ 3044 if (s->type == O_LIMIT_PARENT) \ 3045 uma_zfree(V_dyn_parent_zone, s->limit); \ 3046 else \ 3047 uma_zfree(V_dyn_data_zone, s->data); \ 3048 uma_zfree(V_dyn_ ## af ## _zone, s); \ 3049 } \ 3050 } while (0) 3051 for (bucket = 0; bucket < V_curr_dyn_buckets; bucket++) { 3052 DYN_BUCKET_LOCK_DESTROY(V_dyn_bucket_lock, bucket); 3053 3054 DYN_FREE_STATES_FORCED(CK_, s4, ipv4, ipv4[bucket], entry); 3055 DYN_FREE_STATES_FORCED(CK_, s4, ipv4, ipv4_parent[bucket], 3056 entry); 3057 #ifdef INET6 3058 DYN_FREE_STATES_FORCED(CK_, s6, ipv6, ipv6[bucket], entry); 3059 DYN_FREE_STATES_FORCED(CK_, s6, ipv6, ipv6_parent[bucket], 3060 entry); 3061 #endif /* INET6 */ 3062 } 3063 DYN_FREE_STATES_FORCED(, s4, ipv4, expired_ipv4, expired); 3064 #ifdef INET6 3065 DYN_FREE_STATES_FORCED(, s6, ipv6, expired_ipv6, expired); 3066 #endif 3067 #undef DYN_FREE_STATES_FORCED 3068 3069 uma_zdestroy(V_dyn_ipv4_zone); 3070 uma_zdestroy(V_dyn_data_zone); 3071 uma_zdestroy(V_dyn_parent_zone); 3072 #ifdef INET6 3073 uma_zdestroy(V_dyn_ipv6_zone); 3074 free(V_dyn_ipv6, M_IPFW); 3075 free(V_dyn_ipv6_parent, M_IPFW); 3076 free(V_dyn_ipv6_add, M_IPFW); 3077 free(V_dyn_ipv6_parent_add, M_IPFW); 3078 free(V_dyn_ipv6_del, M_IPFW); 3079 free(V_dyn_ipv6_parent_del, M_IPFW); 3080 #endif 3081 free(V_dyn_bucket_lock, M_IPFW); 3082 free(V_dyn_ipv4, M_IPFW); 3083 free(V_dyn_ipv4_parent, M_IPFW); 3084 free(V_dyn_ipv4_add, M_IPFW); 3085 free(V_dyn_ipv4_parent_add, M_IPFW); 3086 free(V_dyn_ipv4_del, M_IPFW); 3087 free(V_dyn_ipv4_parent_del, M_IPFW); 3088 if (IS_DEFAULT_VNET(curvnet)) 3089 free(dyn_hp_cache, M_IPFW); 3090 } 3091 3092 3093