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