1 /*- 2 * Copyright (c) 2015-2017 Patrick Kelsey 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 /* 28 * This is an implementation of TCP Fast Open (TFO) [RFC7413]. To include 29 * this code, add the following line to your kernel config: 30 * 31 * options TCP_RFC7413 32 * 33 * 34 * The generated TFO cookies are the 64-bit output of 35 * SipHash24(key=<16-byte-key>, msg=<client-ip>). Multiple concurrent valid 36 * keys are supported so that time-based rolling cookie invalidation 37 * policies can be implemented in the system. The default number of 38 * concurrent keys is 2. This can be adjusted in the kernel config as 39 * follows: 40 * 41 * options TCP_RFC7413_MAX_KEYS=<num-keys> 42 * 43 * 44 * In addition to the facilities defined in RFC7413, this implementation 45 * supports a pre-shared key (PSK) mode of operation in which the TFO server 46 * requires the client to be in posession of a shared secret in order for 47 * the client to be able to successfully open TFO connections with the 48 * server. This is useful, for example, in environments where TFO servers 49 * are exposed to both internal and external clients and only wish to allow 50 * TFO connections from internal clients. 51 * 52 * In the PSK mode of operation, the server generates and sends TFO cookies 53 * to requesting clients as usual. However, when validating cookies 54 * received in TFO SYNs from clients, the server requires the 55 * client-supplied cookie to equal SipHash24(key=<16-byte-psk>, 56 * msg=<cookie-sent-to-client>). 57 * 58 * Multiple concurrent valid pre-shared keys are supported so that 59 * time-based rolling PSK invalidation policies can be implemented in the 60 * system. The default number of concurrent pre-shared keys is 2. This can 61 * be adjusted in the kernel config as follows: 62 * 63 * options TCP_RFC7413_MAX_PSKS=<num-psks> 64 * 65 * 66 * The following TFO-specific sysctls are defined: 67 * 68 * net.inet.tcp.fastopen.acceptany (RW, default 0) 69 * When non-zero, all client-supplied TFO cookies will be considered to 70 * be valid. 71 * 72 * net.inet.tcp.fastopen.autokey (RW, default 120) 73 * When this and net.inet.tcp.fastopen.server_enable are non-zero, a new 74 * key will be automatically generated after this many seconds. 75 * 76 * net.inet.tcp.fastopen.ccache_bucket_limit 77 * (RWTUN, default TCP_FASTOPEN_CCACHE_BUCKET_LIMIT_DEFAULT) 78 * The maximum number of entries in a client cookie cache bucket. 79 * 80 * net.inet.tcp.fastopen.ccache_buckets 81 * (RDTUN, default TCP_FASTOPEN_CCACHE_BUCKETS_DEFAULT) 82 * The number of client cookie cache buckets. 83 * 84 * net.inet.tcp.fastopen.ccache_list (RO) 85 * Print the client cookie cache. 86 * 87 * net.inet.tcp.fastopen.client_enable (RW, default 0) 88 * When zero, no new active (i.e., client) TFO connections can be 89 * created. On the transition from enabled to disabled, the client 90 * cookie cache is cleared and disabled. The transition from enabled to 91 * disabled does not affect any active TFO connections in progress; it 92 * only prevents new ones from being made. 93 * 94 * net.inet.tcp.fastopen.keylen (RD) 95 * The key length in bytes. 96 * 97 * net.inet.tcp.fastopen.maxkeys (RD) 98 * The maximum number of keys supported. 99 * 100 * net.inet.tcp.fastopen.maxpsks (RD) 101 * The maximum number of pre-shared keys supported. 102 * 103 * net.inet.tcp.fastopen.numkeys (RD) 104 * The current number of keys installed. 105 * 106 * net.inet.tcp.fastopen.numpsks (RD) 107 * The current number of pre-shared keys installed. 108 * 109 * net.inet.tcp.fastopen.path_disable_time 110 * (RW, default TCP_FASTOPEN_PATH_DISABLE_TIME_DEFAULT) 111 * When a failure occurs while trying to create a new active (i.e., 112 * client) TFO connection, new active connections on the same path, as 113 * determined by the tuple {client_ip, server_ip, server_port}, will be 114 * forced to be non-TFO for this many seconds. Note that the path 115 * disable mechanism relies on state stored in client cookie cache 116 * entries, so it is possible for the disable time for a given path to 117 * be reduced if the corresponding client cookie cache entry is reused 118 * due to resource pressure before the disable period has elapsed. 119 * 120 * net.inet.tcp.fastopen.psk_enable (RW, default 0) 121 * When non-zero, pre-shared key (PSK) mode is enabled for all TFO 122 * servers. On the transition from enabled to disabled, all installed 123 * pre-shared keys are removed. 124 * 125 * net.inet.tcp.fastopen.server_enable (RW, default 0) 126 * When zero, no new passive (i.e., server) TFO connections can be 127 * created. On the transition from enabled to disabled, all installed 128 * keys and pre-shared keys are removed. On the transition from 129 * disabled to enabled, if net.inet.tcp.fastopen.autokey is non-zero and 130 * there are no keys installed, a new key will be generated immediately. 131 * The transition from enabled to disabled does not affect any passive 132 * TFO connections in progress; it only prevents new ones from being 133 * made. 134 * 135 * net.inet.tcp.fastopen.setkey (WR) 136 * Install a new key by writing net.inet.tcp.fastopen.keylen bytes to 137 * this sysctl. 138 * 139 * net.inet.tcp.fastopen.setpsk (WR) 140 * Install a new pre-shared key by writing net.inet.tcp.fastopen.keylen 141 * bytes to this sysctl. 142 * 143 * In order for TFO connections to be created via a listen socket, that 144 * socket must have the TCP_FASTOPEN socket option set on it. This option 145 * can be set on the socket either before or after the listen() is invoked. 146 * Clearing this option on a listen socket after it has been set has no 147 * effect on existing TFO connections or TFO connections in progress; it 148 * only prevents new TFO connections from being made. 149 * 150 * For passively-created sockets, the TCP_FASTOPEN socket option can be 151 * queried to determine whether the connection was established using TFO. 152 * Note that connections that are established via a TFO SYN, but that fall 153 * back to using a non-TFO SYN|ACK will have the TCP_FASTOPEN socket option 154 * set. 155 * 156 * Per the RFC, this implementation limits the number of TFO connections 157 * that can be in the SYN_RECEIVED state on a per listen-socket basis. 158 * Whenever this limit is exceeded, requests for new TFO connections are 159 * serviced as non-TFO requests. Without such a limit, given a valid TFO 160 * cookie, an attacker could keep the listen queue in an overflow condition 161 * using a TFO SYN flood. This implementation sets the limit at half the 162 * configured listen backlog. 163 * 164 */ 165 166 #include <sys/cdefs.h> 167 #include "opt_inet.h" 168 169 #include <sys/param.h> 170 #include <sys/jail.h> 171 #include <sys/kernel.h> 172 #include <sys/hash.h> 173 #include <sys/limits.h> 174 #include <sys/lock.h> 175 #include <sys/proc.h> 176 #include <sys/rmlock.h> 177 #include <sys/sbuf.h> 178 #include <sys/socket.h> 179 #include <sys/socketvar.h> 180 #include <sys/sysctl.h> 181 #include <sys/systm.h> 182 183 #include <crypto/siphash/siphash.h> 184 185 #include <net/vnet.h> 186 187 #include <netinet/in.h> 188 #include <netinet/in_pcb.h> 189 #include <netinet/tcp_var.h> 190 #include <netinet/tcp_fastopen.h> 191 192 #define TCP_FASTOPEN_KEY_LEN SIPHASH_KEY_LENGTH 193 194 #if TCP_FASTOPEN_PSK_LEN != TCP_FASTOPEN_KEY_LEN 195 #error TCP_FASTOPEN_PSK_LEN must be equal to TCP_FASTOPEN_KEY_LEN 196 #endif 197 198 /* 199 * Because a PSK-mode setsockopt() uses tcpcb.t_tfo_cookie.client to hold 200 * the PSK until the connect occurs. 201 */ 202 #if TCP_FASTOPEN_MAX_COOKIE_LEN < TCP_FASTOPEN_PSK_LEN 203 #error TCP_FASTOPEN_MAX_COOKIE_LEN must be >= TCP_FASTOPEN_PSK_LEN 204 #endif 205 206 #define TCP_FASTOPEN_CCACHE_BUCKET_LIMIT_DEFAULT 16 207 #define TCP_FASTOPEN_CCACHE_BUCKETS_DEFAULT 2048 /* must be power of 2 */ 208 209 #define TCP_FASTOPEN_PATH_DISABLE_TIME_DEFAULT 900 /* seconds */ 210 211 #if !defined(TCP_RFC7413_MAX_KEYS) || (TCP_RFC7413_MAX_KEYS < 1) 212 #define TCP_FASTOPEN_MAX_KEYS 2 213 #else 214 #define TCP_FASTOPEN_MAX_KEYS TCP_RFC7413_MAX_KEYS 215 #endif 216 217 #if TCP_FASTOPEN_MAX_KEYS > 10 218 #undef TCP_FASTOPEN_MAX_KEYS 219 #define TCP_FASTOPEN_MAX_KEYS 10 220 #endif 221 222 #if !defined(TCP_RFC7413_MAX_PSKS) || (TCP_RFC7413_MAX_PSKS < 1) 223 #define TCP_FASTOPEN_MAX_PSKS 2 224 #else 225 #define TCP_FASTOPEN_MAX_PSKS TCP_RFC7413_MAX_PSKS 226 #endif 227 228 #if TCP_FASTOPEN_MAX_PSKS > 10 229 #undef TCP_FASTOPEN_MAX_PSKS 230 #define TCP_FASTOPEN_MAX_PSKS 10 231 #endif 232 233 struct tcp_fastopen_keylist { 234 unsigned int newest; 235 unsigned int newest_psk; 236 uint8_t key[TCP_FASTOPEN_MAX_KEYS][TCP_FASTOPEN_KEY_LEN]; 237 uint8_t psk[TCP_FASTOPEN_MAX_PSKS][TCP_FASTOPEN_KEY_LEN]; 238 }; 239 240 struct tcp_fastopen_callout { 241 struct callout c; 242 struct vnet *v; 243 }; 244 245 static struct tcp_fastopen_ccache_entry *tcp_fastopen_ccache_lookup( 246 struct in_conninfo *, struct tcp_fastopen_ccache_bucket **); 247 static struct tcp_fastopen_ccache_entry *tcp_fastopen_ccache_create( 248 struct tcp_fastopen_ccache_bucket *, struct in_conninfo *, uint16_t, uint8_t, 249 uint8_t *); 250 static void tcp_fastopen_ccache_bucket_trim(struct tcp_fastopen_ccache_bucket *, 251 unsigned int); 252 static void tcp_fastopen_ccache_entry_drop(struct tcp_fastopen_ccache_entry *, 253 struct tcp_fastopen_ccache_bucket *); 254 255 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, fastopen, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 256 "TCP Fast Open"); 257 258 VNET_DEFINE_STATIC(int, tcp_fastopen_acceptany) = 0; 259 #define V_tcp_fastopen_acceptany VNET(tcp_fastopen_acceptany) 260 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, acceptany, 261 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_fastopen_acceptany), 0, 262 "Accept any non-empty cookie"); 263 264 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_autokey) = 120; 265 #define V_tcp_fastopen_autokey VNET(tcp_fastopen_autokey) 266 static int sysctl_net_inet_tcp_fastopen_autokey(SYSCTL_HANDLER_ARGS); 267 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, autokey, 268 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 269 NULL, 0, &sysctl_net_inet_tcp_fastopen_autokey, "IU", 270 "Number of seconds between auto-generation of a new key; zero disables"); 271 272 static int sysctl_net_inet_tcp_fastopen_ccache_bucket_limit(SYSCTL_HANDLER_ARGS); 273 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, ccache_bucket_limit, 274 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, 275 NULL, 0, &sysctl_net_inet_tcp_fastopen_ccache_bucket_limit, "IU", 276 "Max entries per bucket in client cookie cache"); 277 278 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_ccache_buckets) = 279 TCP_FASTOPEN_CCACHE_BUCKETS_DEFAULT; 280 #define V_tcp_fastopen_ccache_buckets VNET(tcp_fastopen_ccache_buckets) 281 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, ccache_buckets, 282 CTLFLAG_VNET | CTLFLAG_RDTUN, &VNET_NAME(tcp_fastopen_ccache_buckets), 0, 283 "Client cookie cache number of buckets (power of 2)"); 284 285 VNET_DEFINE(unsigned int, tcp_fastopen_client_enable) = 1; 286 static int sysctl_net_inet_tcp_fastopen_client_enable(SYSCTL_HANDLER_ARGS); 287 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, client_enable, 288 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 289 NULL, 0, &sysctl_net_inet_tcp_fastopen_client_enable, "IU", 290 "Enable/disable TCP Fast Open client functionality"); 291 292 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, keylen, 293 CTLFLAG_RD, SYSCTL_NULL_INT_PTR, TCP_FASTOPEN_KEY_LEN, 294 "Key length in bytes"); 295 296 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, maxkeys, 297 CTLFLAG_RD, SYSCTL_NULL_INT_PTR, TCP_FASTOPEN_MAX_KEYS, 298 "Maximum number of keys supported"); 299 300 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, maxpsks, 301 CTLFLAG_RD, SYSCTL_NULL_INT_PTR, TCP_FASTOPEN_MAX_PSKS, 302 "Maximum number of pre-shared keys supported"); 303 304 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_numkeys) = 0; 305 #define V_tcp_fastopen_numkeys VNET(tcp_fastopen_numkeys) 306 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, numkeys, 307 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(tcp_fastopen_numkeys), 0, 308 "Number of keys installed"); 309 310 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_numpsks) = 0; 311 #define V_tcp_fastopen_numpsks VNET(tcp_fastopen_numpsks) 312 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, numpsks, 313 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(tcp_fastopen_numpsks), 0, 314 "Number of pre-shared keys installed"); 315 316 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_path_disable_time) = 317 TCP_FASTOPEN_PATH_DISABLE_TIME_DEFAULT; 318 #define V_tcp_fastopen_path_disable_time VNET(tcp_fastopen_path_disable_time) 319 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, path_disable_time, 320 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_fastopen_path_disable_time), 0, 321 "Seconds a TFO failure disables a {client_ip, server_ip, server_port} path"); 322 323 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_psk_enable) = 0; 324 #define V_tcp_fastopen_psk_enable VNET(tcp_fastopen_psk_enable) 325 static int sysctl_net_inet_tcp_fastopen_psk_enable(SYSCTL_HANDLER_ARGS); 326 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, psk_enable, 327 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 328 NULL, 0, &sysctl_net_inet_tcp_fastopen_psk_enable, "IU", 329 "Enable/disable TCP Fast Open server pre-shared key mode"); 330 331 VNET_DEFINE(unsigned int, tcp_fastopen_server_enable) = 0; 332 static int sysctl_net_inet_tcp_fastopen_server_enable(SYSCTL_HANDLER_ARGS); 333 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, server_enable, 334 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 335 NULL, 0, &sysctl_net_inet_tcp_fastopen_server_enable, "IU", 336 "Enable/disable TCP Fast Open server functionality"); 337 338 static int sysctl_net_inet_tcp_fastopen_setkey(SYSCTL_HANDLER_ARGS); 339 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, setkey, 340 CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_WR | CTLFLAG_MPSAFE, 341 NULL, 0, &sysctl_net_inet_tcp_fastopen_setkey, "", 342 "Install a new key"); 343 344 static int sysctl_net_inet_tcp_fastopen_setpsk(SYSCTL_HANDLER_ARGS); 345 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, setpsk, 346 CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_WR | CTLFLAG_MPSAFE, 347 NULL, 0, &sysctl_net_inet_tcp_fastopen_setpsk, "", 348 "Install a new pre-shared key"); 349 350 static int sysctl_net_inet_tcp_fastopen_ccache_list(SYSCTL_HANDLER_ARGS); 351 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, ccache_list, 352 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP | CTLFLAG_MPSAFE, 353 NULL, 0, sysctl_net_inet_tcp_fastopen_ccache_list, "A", 354 "List of all client cookie cache entries"); 355 356 VNET_DEFINE_STATIC(struct rmlock, tcp_fastopen_keylock); 357 #define V_tcp_fastopen_keylock VNET(tcp_fastopen_keylock) 358 359 #define TCP_FASTOPEN_KEYS_RLOCK(t) rm_rlock(&V_tcp_fastopen_keylock, (t)) 360 #define TCP_FASTOPEN_KEYS_RUNLOCK(t) rm_runlock(&V_tcp_fastopen_keylock, (t)) 361 #define TCP_FASTOPEN_KEYS_WLOCK() rm_wlock(&V_tcp_fastopen_keylock) 362 #define TCP_FASTOPEN_KEYS_WUNLOCK() rm_wunlock(&V_tcp_fastopen_keylock) 363 364 VNET_DEFINE_STATIC(struct tcp_fastopen_keylist, tcp_fastopen_keys); 365 #define V_tcp_fastopen_keys VNET(tcp_fastopen_keys) 366 367 VNET_DEFINE_STATIC(struct tcp_fastopen_callout, tcp_fastopen_autokey_ctx); 368 #define V_tcp_fastopen_autokey_ctx VNET(tcp_fastopen_autokey_ctx) 369 370 VNET_DEFINE_STATIC(uma_zone_t, counter_zone); 371 #define V_counter_zone VNET(counter_zone) 372 373 static MALLOC_DEFINE(M_TCP_FASTOPEN_CCACHE, "tfo_ccache", "TFO client cookie cache buckets"); 374 375 VNET_DEFINE_STATIC(struct tcp_fastopen_ccache, tcp_fastopen_ccache); 376 #define V_tcp_fastopen_ccache VNET(tcp_fastopen_ccache) 377 378 #define CCB_LOCK(ccb) mtx_lock(&(ccb)->ccb_mtx) 379 #define CCB_UNLOCK(ccb) mtx_unlock(&(ccb)->ccb_mtx) 380 #define CCB_LOCK_ASSERT(ccb) mtx_assert(&(ccb)->ccb_mtx, MA_OWNED) 381 382 void 383 tcp_fastopen_init(void) 384 { 385 unsigned int i; 386 387 V_counter_zone = uma_zcreate("tfo", sizeof(unsigned int), 388 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 389 rm_init(&V_tcp_fastopen_keylock, "tfo_keylock"); 390 callout_init_rm(&V_tcp_fastopen_autokey_ctx.c, 391 &V_tcp_fastopen_keylock, 0); 392 V_tcp_fastopen_autokey_ctx.v = curvnet; 393 V_tcp_fastopen_keys.newest = TCP_FASTOPEN_MAX_KEYS - 1; 394 V_tcp_fastopen_keys.newest_psk = TCP_FASTOPEN_MAX_PSKS - 1; 395 396 /* May already be non-zero if kernel tunable was set */ 397 if (V_tcp_fastopen_ccache.bucket_limit == 0) 398 V_tcp_fastopen_ccache.bucket_limit = 399 TCP_FASTOPEN_CCACHE_BUCKET_LIMIT_DEFAULT; 400 401 /* May already be non-zero if kernel tunable was set */ 402 if ((V_tcp_fastopen_ccache_buckets == 0) || 403 !powerof2(V_tcp_fastopen_ccache_buckets)) 404 V_tcp_fastopen_ccache.buckets = 405 TCP_FASTOPEN_CCACHE_BUCKETS_DEFAULT; 406 else 407 V_tcp_fastopen_ccache.buckets = V_tcp_fastopen_ccache_buckets; 408 409 V_tcp_fastopen_ccache.mask = V_tcp_fastopen_ccache.buckets - 1; 410 V_tcp_fastopen_ccache.secret = arc4random(); 411 412 V_tcp_fastopen_ccache.base = malloc(V_tcp_fastopen_ccache.buckets * 413 sizeof(struct tcp_fastopen_ccache_bucket), M_TCP_FASTOPEN_CCACHE, 414 M_WAITOK | M_ZERO); 415 416 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 417 TAILQ_INIT(&V_tcp_fastopen_ccache.base[i].ccb_entries); 418 mtx_init(&V_tcp_fastopen_ccache.base[i].ccb_mtx, "tfo_ccache_bucket", 419 NULL, MTX_DEF); 420 if (V_tcp_fastopen_client_enable) { 421 /* enable bucket */ 422 V_tcp_fastopen_ccache.base[i].ccb_num_entries = 0; 423 } else { 424 /* disable bucket */ 425 V_tcp_fastopen_ccache.base[i].ccb_num_entries = -1; 426 } 427 V_tcp_fastopen_ccache.base[i].ccb_ccache = &V_tcp_fastopen_ccache; 428 } 429 430 /* 431 * Note that while the total number of entries in the cookie cache 432 * is limited by the table management logic to 433 * V_tcp_fastopen_ccache.buckets * 434 * V_tcp_fastopen_ccache.bucket_limit, the total number of items in 435 * this zone can exceed that amount by the number of CPUs in the 436 * system times the maximum number of unallocated items that can be 437 * present in each UMA per-CPU cache for this zone. 438 */ 439 V_tcp_fastopen_ccache.zone = uma_zcreate("tfo_ccache_entries", 440 sizeof(struct tcp_fastopen_ccache_entry), NULL, NULL, NULL, NULL, 441 UMA_ALIGN_CACHE, 0); 442 } 443 444 void 445 tcp_fastopen_destroy(void) 446 { 447 struct tcp_fastopen_ccache_bucket *ccb; 448 unsigned int i; 449 450 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 451 ccb = &V_tcp_fastopen_ccache.base[i]; 452 tcp_fastopen_ccache_bucket_trim(ccb, 0); 453 mtx_destroy(&ccb->ccb_mtx); 454 } 455 456 KASSERT(uma_zone_get_cur(V_tcp_fastopen_ccache.zone) == 0, 457 ("%s: TFO ccache zone allocation count not 0", __func__)); 458 uma_zdestroy(V_tcp_fastopen_ccache.zone); 459 free(V_tcp_fastopen_ccache.base, M_TCP_FASTOPEN_CCACHE); 460 461 callout_drain(&V_tcp_fastopen_autokey_ctx.c); 462 rm_destroy(&V_tcp_fastopen_keylock); 463 uma_zdestroy(V_counter_zone); 464 } 465 466 unsigned int * 467 tcp_fastopen_alloc_counter(void) 468 { 469 unsigned int *counter; 470 counter = uma_zalloc(V_counter_zone, M_NOWAIT); 471 if (counter) 472 *counter = 1; 473 return (counter); 474 } 475 476 void 477 tcp_fastopen_decrement_counter(unsigned int *counter) 478 { 479 if (*counter == 1) 480 uma_zfree(V_counter_zone, counter); 481 else 482 atomic_subtract_int(counter, 1); 483 } 484 485 static void 486 tcp_fastopen_addkey_locked(uint8_t *key) 487 { 488 489 V_tcp_fastopen_keys.newest++; 490 if (V_tcp_fastopen_keys.newest == TCP_FASTOPEN_MAX_KEYS) 491 V_tcp_fastopen_keys.newest = 0; 492 memcpy(V_tcp_fastopen_keys.key[V_tcp_fastopen_keys.newest], key, 493 TCP_FASTOPEN_KEY_LEN); 494 if (V_tcp_fastopen_numkeys < TCP_FASTOPEN_MAX_KEYS) 495 V_tcp_fastopen_numkeys++; 496 } 497 498 static void 499 tcp_fastopen_addpsk_locked(uint8_t *psk) 500 { 501 502 V_tcp_fastopen_keys.newest_psk++; 503 if (V_tcp_fastopen_keys.newest_psk == TCP_FASTOPEN_MAX_PSKS) 504 V_tcp_fastopen_keys.newest_psk = 0; 505 memcpy(V_tcp_fastopen_keys.psk[V_tcp_fastopen_keys.newest_psk], psk, 506 TCP_FASTOPEN_KEY_LEN); 507 if (V_tcp_fastopen_numpsks < TCP_FASTOPEN_MAX_PSKS) 508 V_tcp_fastopen_numpsks++; 509 } 510 511 static void 512 tcp_fastopen_autokey_locked(void) 513 { 514 uint8_t newkey[TCP_FASTOPEN_KEY_LEN]; 515 516 arc4rand(newkey, TCP_FASTOPEN_KEY_LEN, 0); 517 tcp_fastopen_addkey_locked(newkey); 518 } 519 520 static void 521 tcp_fastopen_autokey_callout(void *arg) 522 { 523 struct tcp_fastopen_callout *ctx = arg; 524 525 CURVNET_SET(ctx->v); 526 tcp_fastopen_autokey_locked(); 527 callout_reset(&ctx->c, V_tcp_fastopen_autokey * hz, 528 tcp_fastopen_autokey_callout, ctx); 529 CURVNET_RESTORE(); 530 } 531 532 static uint64_t 533 tcp_fastopen_make_cookie(uint8_t key[SIPHASH_KEY_LENGTH], struct in_conninfo *inc) 534 { 535 SIPHASH_CTX ctx; 536 uint64_t siphash; 537 538 SipHash24_Init(&ctx); 539 SipHash_SetKey(&ctx, key); 540 switch (inc->inc_flags & INC_ISIPV6) { 541 #ifdef INET 542 case 0: 543 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(inc->inc_faddr)); 544 break; 545 #endif 546 #ifdef INET6 547 case INC_ISIPV6: 548 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(inc->inc6_faddr)); 549 break; 550 #endif 551 } 552 SipHash_Final((u_int8_t *)&siphash, &ctx); 553 554 return (siphash); 555 } 556 557 static uint64_t 558 tcp_fastopen_make_psk_cookie(uint8_t *psk, uint8_t *cookie, uint8_t cookie_len) 559 { 560 SIPHASH_CTX ctx; 561 uint64_t psk_cookie; 562 563 SipHash24_Init(&ctx); 564 SipHash_SetKey(&ctx, psk); 565 SipHash_Update(&ctx, cookie, cookie_len); 566 SipHash_Final((u_int8_t *)&psk_cookie, &ctx); 567 568 return (psk_cookie); 569 } 570 571 static int 572 tcp_fastopen_find_cookie_match_locked(uint8_t *wire_cookie, uint64_t *cur_cookie) 573 { 574 unsigned int i, psk_index; 575 uint64_t psk_cookie; 576 577 if (V_tcp_fastopen_psk_enable) { 578 psk_index = V_tcp_fastopen_keys.newest_psk; 579 for (i = 0; i < V_tcp_fastopen_numpsks; i++) { 580 psk_cookie = 581 tcp_fastopen_make_psk_cookie( 582 V_tcp_fastopen_keys.psk[psk_index], 583 (uint8_t *)cur_cookie, 584 TCP_FASTOPEN_COOKIE_LEN); 585 586 if (memcmp(wire_cookie, &psk_cookie, 587 TCP_FASTOPEN_COOKIE_LEN) == 0) 588 return (1); 589 590 if (psk_index == 0) 591 psk_index = TCP_FASTOPEN_MAX_PSKS - 1; 592 else 593 psk_index--; 594 } 595 } else if (memcmp(wire_cookie, cur_cookie, TCP_FASTOPEN_COOKIE_LEN) == 0) 596 return (1); 597 598 return (0); 599 } 600 601 /* 602 * Return values: 603 * -1 the cookie is invalid and no valid cookie is available 604 * 0 the cookie is invalid and the latest cookie has been returned 605 * 1 the cookie is valid and the latest cookie has been returned 606 */ 607 int 608 tcp_fastopen_check_cookie(struct in_conninfo *inc, uint8_t *cookie, 609 unsigned int len, uint64_t *latest_cookie) 610 { 611 struct rm_priotracker tracker; 612 unsigned int i, key_index; 613 int rv; 614 uint64_t cur_cookie; 615 616 if (V_tcp_fastopen_acceptany) { 617 *latest_cookie = 0; 618 return (1); 619 } 620 621 TCP_FASTOPEN_KEYS_RLOCK(&tracker); 622 if (len != TCP_FASTOPEN_COOKIE_LEN) { 623 if (V_tcp_fastopen_numkeys > 0) { 624 *latest_cookie = 625 tcp_fastopen_make_cookie( 626 V_tcp_fastopen_keys.key[V_tcp_fastopen_keys.newest], 627 inc); 628 rv = 0; 629 } else 630 rv = -1; 631 goto out; 632 } 633 634 /* 635 * Check against each available key, from newest to oldest. 636 */ 637 key_index = V_tcp_fastopen_keys.newest; 638 for (i = 0; i < V_tcp_fastopen_numkeys; i++) { 639 cur_cookie = 640 tcp_fastopen_make_cookie(V_tcp_fastopen_keys.key[key_index], 641 inc); 642 if (i == 0) 643 *latest_cookie = cur_cookie; 644 rv = tcp_fastopen_find_cookie_match_locked(cookie, &cur_cookie); 645 if (rv) 646 goto out; 647 if (key_index == 0) 648 key_index = TCP_FASTOPEN_MAX_KEYS - 1; 649 else 650 key_index--; 651 } 652 rv = 0; 653 654 out: 655 TCP_FASTOPEN_KEYS_RUNLOCK(&tracker); 656 return (rv); 657 } 658 659 static int 660 sysctl_net_inet_tcp_fastopen_autokey(SYSCTL_HANDLER_ARGS) 661 { 662 int error; 663 unsigned int new; 664 665 new = V_tcp_fastopen_autokey; 666 error = sysctl_handle_int(oidp, &new, 0, req); 667 if (error == 0 && req->newptr) { 668 if (new > (INT_MAX / hz)) 669 return (EINVAL); 670 671 TCP_FASTOPEN_KEYS_WLOCK(); 672 if (V_tcp_fastopen_server_enable) { 673 if (V_tcp_fastopen_autokey && !new) 674 callout_stop(&V_tcp_fastopen_autokey_ctx.c); 675 else if (new) 676 callout_reset(&V_tcp_fastopen_autokey_ctx.c, 677 new * hz, tcp_fastopen_autokey_callout, 678 &V_tcp_fastopen_autokey_ctx); 679 } 680 V_tcp_fastopen_autokey = new; 681 TCP_FASTOPEN_KEYS_WUNLOCK(); 682 } 683 684 return (error); 685 } 686 687 static int 688 sysctl_net_inet_tcp_fastopen_psk_enable(SYSCTL_HANDLER_ARGS) 689 { 690 int error; 691 unsigned int new; 692 693 new = V_tcp_fastopen_psk_enable; 694 error = sysctl_handle_int(oidp, &new, 0, req); 695 if (error == 0 && req->newptr) { 696 if (V_tcp_fastopen_psk_enable && !new) { 697 /* enabled -> disabled */ 698 TCP_FASTOPEN_KEYS_WLOCK(); 699 V_tcp_fastopen_numpsks = 0; 700 V_tcp_fastopen_keys.newest_psk = 701 TCP_FASTOPEN_MAX_PSKS - 1; 702 V_tcp_fastopen_psk_enable = 0; 703 TCP_FASTOPEN_KEYS_WUNLOCK(); 704 } else if (!V_tcp_fastopen_psk_enable && new) { 705 /* disabled -> enabled */ 706 TCP_FASTOPEN_KEYS_WLOCK(); 707 V_tcp_fastopen_psk_enable = 1; 708 TCP_FASTOPEN_KEYS_WUNLOCK(); 709 } 710 } 711 return (error); 712 } 713 714 static int 715 sysctl_net_inet_tcp_fastopen_server_enable(SYSCTL_HANDLER_ARGS) 716 { 717 int error; 718 unsigned int new; 719 720 new = V_tcp_fastopen_server_enable; 721 error = sysctl_handle_int(oidp, &new, 0, req); 722 if (error == 0 && req->newptr) { 723 if (V_tcp_fastopen_server_enable && !new) { 724 /* enabled -> disabled */ 725 TCP_FASTOPEN_KEYS_WLOCK(); 726 V_tcp_fastopen_numkeys = 0; 727 V_tcp_fastopen_keys.newest = TCP_FASTOPEN_MAX_KEYS - 1; 728 if (V_tcp_fastopen_autokey) 729 callout_stop(&V_tcp_fastopen_autokey_ctx.c); 730 V_tcp_fastopen_numpsks = 0; 731 V_tcp_fastopen_keys.newest_psk = 732 TCP_FASTOPEN_MAX_PSKS - 1; 733 V_tcp_fastopen_server_enable = 0; 734 TCP_FASTOPEN_KEYS_WUNLOCK(); 735 } else if (!V_tcp_fastopen_server_enable && new) { 736 /* disabled -> enabled */ 737 TCP_FASTOPEN_KEYS_WLOCK(); 738 if (V_tcp_fastopen_autokey && 739 (V_tcp_fastopen_numkeys == 0)) { 740 tcp_fastopen_autokey_locked(); 741 callout_reset(&V_tcp_fastopen_autokey_ctx.c, 742 V_tcp_fastopen_autokey * hz, 743 tcp_fastopen_autokey_callout, 744 &V_tcp_fastopen_autokey_ctx); 745 } 746 V_tcp_fastopen_server_enable = 1; 747 TCP_FASTOPEN_KEYS_WUNLOCK(); 748 } 749 } 750 return (error); 751 } 752 753 static int 754 sysctl_net_inet_tcp_fastopen_setkey(SYSCTL_HANDLER_ARGS) 755 { 756 int error; 757 uint8_t newkey[TCP_FASTOPEN_KEY_LEN]; 758 759 if (req->oldptr != NULL || req->oldlen != 0) 760 return (EINVAL); 761 if (req->newptr == NULL) 762 return (EPERM); 763 if (req->newlen != sizeof(newkey)) 764 return (EINVAL); 765 error = SYSCTL_IN(req, newkey, sizeof(newkey)); 766 if (error) 767 return (error); 768 769 TCP_FASTOPEN_KEYS_WLOCK(); 770 tcp_fastopen_addkey_locked(newkey); 771 TCP_FASTOPEN_KEYS_WUNLOCK(); 772 773 return (0); 774 } 775 776 static int 777 sysctl_net_inet_tcp_fastopen_setpsk(SYSCTL_HANDLER_ARGS) 778 { 779 int error; 780 uint8_t newpsk[TCP_FASTOPEN_KEY_LEN]; 781 782 if (req->oldptr != NULL || req->oldlen != 0) 783 return (EINVAL); 784 if (req->newptr == NULL) 785 return (EPERM); 786 if (req->newlen != sizeof(newpsk)) 787 return (EINVAL); 788 error = SYSCTL_IN(req, newpsk, sizeof(newpsk)); 789 if (error) 790 return (error); 791 792 TCP_FASTOPEN_KEYS_WLOCK(); 793 tcp_fastopen_addpsk_locked(newpsk); 794 TCP_FASTOPEN_KEYS_WUNLOCK(); 795 796 return (0); 797 } 798 799 static int 800 sysctl_net_inet_tcp_fastopen_ccache_bucket_limit(SYSCTL_HANDLER_ARGS) 801 { 802 struct tcp_fastopen_ccache_bucket *ccb; 803 int error; 804 unsigned int new; 805 unsigned int i; 806 807 new = V_tcp_fastopen_ccache.bucket_limit; 808 error = sysctl_handle_int(oidp, &new, 0, req); 809 if (error == 0 && req->newptr) { 810 if ((new == 0) || (new > INT_MAX)) 811 error = EINVAL; 812 else { 813 if (new < V_tcp_fastopen_ccache.bucket_limit) { 814 for (i = 0; i < V_tcp_fastopen_ccache.buckets; 815 i++) { 816 ccb = &V_tcp_fastopen_ccache.base[i]; 817 tcp_fastopen_ccache_bucket_trim(ccb, new); 818 } 819 } 820 V_tcp_fastopen_ccache.bucket_limit = new; 821 } 822 } 823 return (error); 824 } 825 826 static int 827 sysctl_net_inet_tcp_fastopen_client_enable(SYSCTL_HANDLER_ARGS) 828 { 829 struct tcp_fastopen_ccache_bucket *ccb; 830 int error; 831 unsigned int new, i; 832 833 new = V_tcp_fastopen_client_enable; 834 error = sysctl_handle_int(oidp, &new, 0, req); 835 if (error == 0 && req->newptr) { 836 if (V_tcp_fastopen_client_enable && !new) { 837 /* enabled -> disabled */ 838 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 839 ccb = &V_tcp_fastopen_ccache.base[i]; 840 KASSERT(ccb->ccb_num_entries > -1, 841 ("%s: ccb->ccb_num_entries %d is negative", 842 __func__, ccb->ccb_num_entries)); 843 tcp_fastopen_ccache_bucket_trim(ccb, 0); 844 } 845 V_tcp_fastopen_client_enable = 0; 846 } else if (!V_tcp_fastopen_client_enable && new) { 847 /* disabled -> enabled */ 848 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 849 ccb = &V_tcp_fastopen_ccache.base[i]; 850 CCB_LOCK(ccb); 851 KASSERT(TAILQ_EMPTY(&ccb->ccb_entries), 852 ("%s: ccb->ccb_entries not empty", __func__)); 853 KASSERT(ccb->ccb_num_entries == -1, 854 ("%s: ccb->ccb_num_entries %d not -1", __func__, 855 ccb->ccb_num_entries)); 856 ccb->ccb_num_entries = 0; /* enable bucket */ 857 CCB_UNLOCK(ccb); 858 } 859 V_tcp_fastopen_client_enable = 1; 860 } 861 } 862 return (error); 863 } 864 865 void 866 tcp_fastopen_connect(struct tcpcb *tp) 867 { 868 struct inpcb *inp = tptoinpcb(tp); 869 struct tcp_fastopen_ccache_bucket *ccb; 870 struct tcp_fastopen_ccache_entry *cce; 871 sbintime_t now; 872 uint16_t server_mss; 873 uint64_t psk_cookie; 874 875 psk_cookie = 0; 876 cce = tcp_fastopen_ccache_lookup(&inp->inp_inc, &ccb); 877 if (cce) { 878 if (cce->disable_time == 0) { 879 if ((cce->cookie_len > 0) && 880 (tp->t_tfo_client_cookie_len == 881 TCP_FASTOPEN_PSK_LEN)) { 882 psk_cookie = 883 tcp_fastopen_make_psk_cookie( 884 tp->t_tfo_cookie.client, 885 cce->cookie, cce->cookie_len); 886 } else { 887 tp->t_tfo_client_cookie_len = cce->cookie_len; 888 memcpy(tp->t_tfo_cookie.client, cce->cookie, 889 cce->cookie_len); 890 } 891 server_mss = cce->server_mss; 892 CCB_UNLOCK(ccb); 893 if (tp->t_tfo_client_cookie_len == 894 TCP_FASTOPEN_PSK_LEN && psk_cookie) { 895 tp->t_tfo_client_cookie_len = 896 TCP_FASTOPEN_COOKIE_LEN; 897 memcpy(tp->t_tfo_cookie.client, &psk_cookie, 898 TCP_FASTOPEN_COOKIE_LEN); 899 } 900 tcp_mss(tp, server_mss ? server_mss : -1); 901 tp->snd_wnd = tp->t_maxseg; 902 } else { 903 /* 904 * The path is disabled. Check the time and 905 * possibly re-enable. 906 */ 907 now = getsbinuptime(); 908 if (now - cce->disable_time > 909 ((sbintime_t)V_tcp_fastopen_path_disable_time << 32)) { 910 /* 911 * Re-enable path. Force a TFO cookie 912 * request. Forget the old MSS as it may be 913 * bogus now, and we will rediscover it in 914 * the SYN|ACK. 915 */ 916 cce->disable_time = 0; 917 cce->server_mss = 0; 918 cce->cookie_len = 0; 919 /* 920 * tp->t_tfo... cookie details are already 921 * zero from the tcpcb init. 922 */ 923 } else { 924 /* 925 * Path is disabled, so disable TFO on this 926 * connection. 927 */ 928 tp->t_flags &= ~TF_FASTOPEN; 929 } 930 CCB_UNLOCK(ccb); 931 tcp_mss(tp, -1); 932 /* 933 * snd_wnd is irrelevant since we are either forcing 934 * a TFO cookie request or disabling TFO - either 935 * way, no data with the SYN. 936 */ 937 } 938 } else { 939 /* 940 * A new entry for this path will be created when a SYN|ACK 941 * comes back, or the attempt otherwise fails. 942 */ 943 CCB_UNLOCK(ccb); 944 tcp_mss(tp, -1); 945 /* 946 * snd_wnd is irrelevant since we are forcing a TFO cookie 947 * request. 948 */ 949 } 950 } 951 952 void 953 tcp_fastopen_disable_path(struct tcpcb *tp) 954 { 955 struct in_conninfo *inc = &tptoinpcb(tp)->inp_inc; 956 struct tcp_fastopen_ccache_bucket *ccb; 957 struct tcp_fastopen_ccache_entry *cce; 958 959 cce = tcp_fastopen_ccache_lookup(inc, &ccb); 960 if (cce) { 961 cce->server_mss = 0; 962 cce->cookie_len = 0; 963 /* 964 * Preserve the existing disable time if it is already 965 * disabled. 966 */ 967 if (cce->disable_time == 0) 968 cce->disable_time = getsbinuptime(); 969 } else /* use invalid cookie len to create disabled entry */ 970 tcp_fastopen_ccache_create(ccb, inc, 0, 971 TCP_FASTOPEN_MAX_COOKIE_LEN + 1, NULL); 972 973 CCB_UNLOCK(ccb); 974 tp->t_flags &= ~TF_FASTOPEN; 975 } 976 977 void 978 tcp_fastopen_update_cache(struct tcpcb *tp, uint16_t mss, 979 uint8_t cookie_len, uint8_t *cookie) 980 { 981 struct in_conninfo *inc = &tptoinpcb(tp)->inp_inc; 982 struct tcp_fastopen_ccache_bucket *ccb; 983 struct tcp_fastopen_ccache_entry *cce; 984 985 cce = tcp_fastopen_ccache_lookup(inc, &ccb); 986 if (cce) { 987 if ((cookie_len >= TCP_FASTOPEN_MIN_COOKIE_LEN) && 988 (cookie_len <= TCP_FASTOPEN_MAX_COOKIE_LEN) && 989 ((cookie_len & 0x1) == 0)) { 990 cce->server_mss = mss; 991 cce->cookie_len = cookie_len; 992 memcpy(cce->cookie, cookie, cookie_len); 993 cce->disable_time = 0; 994 } else { 995 /* invalid cookie length, disable entry */ 996 cce->server_mss = 0; 997 cce->cookie_len = 0; 998 /* 999 * Preserve the existing disable time if it is 1000 * already disabled. 1001 */ 1002 if (cce->disable_time == 0) 1003 cce->disable_time = getsbinuptime(); 1004 } 1005 } else 1006 tcp_fastopen_ccache_create(ccb, inc, mss, cookie_len, cookie); 1007 1008 CCB_UNLOCK(ccb); 1009 } 1010 1011 static struct tcp_fastopen_ccache_entry * 1012 tcp_fastopen_ccache_lookup(struct in_conninfo *inc, 1013 struct tcp_fastopen_ccache_bucket **ccbp) 1014 { 1015 struct tcp_fastopen_ccache_bucket *ccb; 1016 struct tcp_fastopen_ccache_entry *cce; 1017 uint32_t last_word; 1018 uint32_t hash; 1019 1020 hash = jenkins_hash32((uint32_t *)&inc->inc_ie.ie_dependladdr, 4, 1021 V_tcp_fastopen_ccache.secret); 1022 hash = jenkins_hash32((uint32_t *)&inc->inc_ie.ie_dependfaddr, 4, 1023 hash); 1024 last_word = inc->inc_fport; 1025 hash = jenkins_hash32(&last_word, 1, hash); 1026 ccb = &V_tcp_fastopen_ccache.base[hash & V_tcp_fastopen_ccache.mask]; 1027 *ccbp = ccb; 1028 CCB_LOCK(ccb); 1029 1030 /* 1031 * Always returns with locked bucket. 1032 */ 1033 TAILQ_FOREACH(cce, &ccb->ccb_entries, cce_link) 1034 if ((!(cce->af == AF_INET6) == !(inc->inc_flags & INC_ISIPV6)) && 1035 (cce->server_port == inc->inc_ie.ie_fport) && 1036 (((cce->af == AF_INET) && 1037 (cce->cce_client_ip.v4.s_addr == inc->inc_laddr.s_addr) && 1038 (cce->cce_server_ip.v4.s_addr == inc->inc_faddr.s_addr)) || 1039 ((cce->af == AF_INET6) && 1040 IN6_ARE_ADDR_EQUAL(&cce->cce_client_ip.v6, &inc->inc6_laddr) && 1041 IN6_ARE_ADDR_EQUAL(&cce->cce_server_ip.v6, &inc->inc6_faddr)))) 1042 break; 1043 1044 return (cce); 1045 } 1046 1047 static struct tcp_fastopen_ccache_entry * 1048 tcp_fastopen_ccache_create(struct tcp_fastopen_ccache_bucket *ccb, 1049 struct in_conninfo *inc, uint16_t mss, uint8_t cookie_len, uint8_t *cookie) 1050 { 1051 struct tcp_fastopen_ccache_entry *cce; 1052 1053 /* 1054 * 1. Create a new entry, or 1055 * 2. Reclaim an existing entry, or 1056 * 3. Fail 1057 */ 1058 1059 CCB_LOCK_ASSERT(ccb); 1060 1061 cce = NULL; 1062 if (ccb->ccb_num_entries < V_tcp_fastopen_ccache.bucket_limit) 1063 cce = uma_zalloc(V_tcp_fastopen_ccache.zone, M_NOWAIT); 1064 1065 if (cce == NULL) { 1066 /* 1067 * At bucket limit, or out of memory - reclaim last 1068 * entry in bucket. 1069 */ 1070 cce = TAILQ_LAST(&ccb->ccb_entries, bucket_entries); 1071 if (cce == NULL) { 1072 /* XXX count this event */ 1073 return (NULL); 1074 } 1075 1076 TAILQ_REMOVE(&ccb->ccb_entries, cce, cce_link); 1077 } else 1078 ccb->ccb_num_entries++; 1079 1080 TAILQ_INSERT_HEAD(&ccb->ccb_entries, cce, cce_link); 1081 cce->af = (inc->inc_flags & INC_ISIPV6) ? AF_INET6 : AF_INET; 1082 if (cce->af == AF_INET) { 1083 cce->cce_client_ip.v4 = inc->inc_laddr; 1084 cce->cce_server_ip.v4 = inc->inc_faddr; 1085 } else { 1086 cce->cce_client_ip.v6 = inc->inc6_laddr; 1087 cce->cce_server_ip.v6 = inc->inc6_faddr; 1088 } 1089 cce->server_port = inc->inc_fport; 1090 if ((cookie_len >= TCP_FASTOPEN_MIN_COOKIE_LEN) && 1091 (cookie_len <= TCP_FASTOPEN_MAX_COOKIE_LEN) && 1092 ((cookie_len & 0x1) == 0)) { 1093 cce->server_mss = mss; 1094 cce->cookie_len = cookie_len; 1095 memcpy(cce->cookie, cookie, cookie_len); 1096 cce->disable_time = 0; 1097 } else { 1098 /* invalid cookie length, disable cce */ 1099 cce->server_mss = 0; 1100 cce->cookie_len = 0; 1101 cce->disable_time = getsbinuptime(); 1102 } 1103 1104 return (cce); 1105 } 1106 1107 static void 1108 tcp_fastopen_ccache_bucket_trim(struct tcp_fastopen_ccache_bucket *ccb, 1109 unsigned int limit) 1110 { 1111 struct tcp_fastopen_ccache_entry *cce, *cce_tmp; 1112 unsigned int entries; 1113 1114 CCB_LOCK(ccb); 1115 entries = 0; 1116 TAILQ_FOREACH_SAFE(cce, &ccb->ccb_entries, cce_link, cce_tmp) { 1117 entries++; 1118 if (entries > limit) 1119 tcp_fastopen_ccache_entry_drop(cce, ccb); 1120 } 1121 KASSERT(ccb->ccb_num_entries <= (int)limit, 1122 ("%s: ccb->ccb_num_entries %d exceeds limit %d", __func__, 1123 ccb->ccb_num_entries, limit)); 1124 if (limit == 0) { 1125 KASSERT(TAILQ_EMPTY(&ccb->ccb_entries), 1126 ("%s: ccb->ccb_entries not empty", __func__)); 1127 ccb->ccb_num_entries = -1; /* disable bucket */ 1128 } 1129 CCB_UNLOCK(ccb); 1130 } 1131 1132 static void 1133 tcp_fastopen_ccache_entry_drop(struct tcp_fastopen_ccache_entry *cce, 1134 struct tcp_fastopen_ccache_bucket *ccb) 1135 { 1136 1137 CCB_LOCK_ASSERT(ccb); 1138 1139 TAILQ_REMOVE(&ccb->ccb_entries, cce, cce_link); 1140 ccb->ccb_num_entries--; 1141 uma_zfree(V_tcp_fastopen_ccache.zone, cce); 1142 } 1143 1144 static int 1145 sysctl_net_inet_tcp_fastopen_ccache_list(SYSCTL_HANDLER_ARGS) 1146 { 1147 struct sbuf sb; 1148 struct tcp_fastopen_ccache_bucket *ccb; 1149 struct tcp_fastopen_ccache_entry *cce; 1150 sbintime_t now, duration, limit; 1151 const int linesize = 128; 1152 int i, error, num_entries; 1153 unsigned int j; 1154 #ifdef INET6 1155 char clt_buf[INET6_ADDRSTRLEN], srv_buf[INET6_ADDRSTRLEN]; 1156 #else 1157 char clt_buf[INET_ADDRSTRLEN], srv_buf[INET_ADDRSTRLEN]; 1158 #endif 1159 1160 if (jailed_without_vnet(curthread->td_ucred) != 0) 1161 return (EPERM); 1162 1163 /* Only allow root to read the client cookie cache */ 1164 if (curthread->td_ucred->cr_uid != 0) 1165 return (EPERM); 1166 1167 num_entries = 0; 1168 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 1169 ccb = &V_tcp_fastopen_ccache.base[i]; 1170 CCB_LOCK(ccb); 1171 if (ccb->ccb_num_entries > 0) 1172 num_entries += ccb->ccb_num_entries; 1173 CCB_UNLOCK(ccb); 1174 } 1175 sbuf_new(&sb, NULL, linesize * (num_entries + 1), SBUF_INCLUDENUL); 1176 1177 sbuf_printf(&sb, 1178 "\nLocal IP address Remote IP address Port MSS" 1179 " Disabled Cookie\n"); 1180 1181 now = getsbinuptime(); 1182 limit = (sbintime_t)V_tcp_fastopen_path_disable_time << 32; 1183 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 1184 ccb = &V_tcp_fastopen_ccache.base[i]; 1185 CCB_LOCK(ccb); 1186 TAILQ_FOREACH(cce, &ccb->ccb_entries, cce_link) { 1187 if (cce->disable_time != 0) { 1188 duration = now - cce->disable_time; 1189 if (limit >= duration) 1190 duration = limit - duration; 1191 else 1192 duration = 0; 1193 } else 1194 duration = 0; 1195 sbuf_printf(&sb, 1196 "%-20s %-20s %5u %5u ", 1197 inet_ntop(cce->af, &cce->cce_client_ip, 1198 clt_buf, sizeof(clt_buf)), 1199 inet_ntop(cce->af, &cce->cce_server_ip, 1200 srv_buf, sizeof(srv_buf)), 1201 ntohs(cce->server_port), 1202 cce->server_mss); 1203 if (duration > 0) 1204 sbuf_printf(&sb, "%7ds ", sbintime_getsec(duration)); 1205 else 1206 sbuf_printf(&sb, "%8s ", "No"); 1207 for (j = 0; j < cce->cookie_len; j++) 1208 sbuf_printf(&sb, "%02x", cce->cookie[j]); 1209 sbuf_putc(&sb, '\n'); 1210 } 1211 CCB_UNLOCK(ccb); 1212 } 1213 error = sbuf_finish(&sb); 1214 if (error == 0) 1215 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 1216 sbuf_delete(&sb); 1217 return (error); 1218 } 1219