Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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sys/netinet/tcp_fastopen.c
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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 __FBSDID("$FreeBSD$"); 168 169 #include "opt_inet.h" 170 171 #include <sys/param.h> 172 #include <sys/jail.h> 173 #include <sys/kernel.h> 174 #include <sys/hash.h> 175 #include <sys/limits.h> 176 #include <sys/lock.h> 177 #include <sys/proc.h> 178 #include <sys/rmlock.h> 179 #include <sys/sbuf.h> 180 #include <sys/socket.h> 181 #include <sys/socketvar.h> 182 #include <sys/sysctl.h> 183 #include <sys/systm.h> 184 185 #include <crypto/siphash/siphash.h> 186 187 #include <net/vnet.h> 188 189 #include <netinet/in.h> 190 #include <netinet/in_pcb.h> 191 #include <netinet/tcp_var.h> 192 #include <netinet/tcp_fastopen.h> 193 194 #define TCP_FASTOPEN_KEY_LEN SIPHASH_KEY_LENGTH 195 196 #if TCP_FASTOPEN_PSK_LEN != TCP_FASTOPEN_KEY_LEN 197 #error TCP_FASTOPEN_PSK_LEN must be equal to TCP_FASTOPEN_KEY_LEN 198 #endif 199 200 /* 201 * Because a PSK-mode setsockopt() uses tcpcb.t_tfo_cookie.client to hold 202 * the PSK until the connect occurs. 203 */ 204 #if TCP_FASTOPEN_MAX_COOKIE_LEN < TCP_FASTOPEN_PSK_LEN 205 #error TCP_FASTOPEN_MAX_COOKIE_LEN must be >= TCP_FASTOPEN_PSK_LEN 206 #endif 207 208 #define TCP_FASTOPEN_CCACHE_BUCKET_LIMIT_DEFAULT 16 209 #define TCP_FASTOPEN_CCACHE_BUCKETS_DEFAULT 2048 /* must be power of 2 */ 210 211 #define TCP_FASTOPEN_PATH_DISABLE_TIME_DEFAULT 900 /* seconds */ 212 213 #if !defined(TCP_RFC7413_MAX_KEYS) || (TCP_RFC7413_MAX_KEYS < 1) 214 #define TCP_FASTOPEN_MAX_KEYS 2 215 #else 216 #define TCP_FASTOPEN_MAX_KEYS TCP_RFC7413_MAX_KEYS 217 #endif 218 219 #if TCP_FASTOPEN_MAX_KEYS > 10 220 #undef TCP_FASTOPEN_MAX_KEYS 221 #define TCP_FASTOPEN_MAX_KEYS 10 222 #endif 223 224 #if !defined(TCP_RFC7413_MAX_PSKS) || (TCP_RFC7413_MAX_PSKS < 1) 225 #define TCP_FASTOPEN_MAX_PSKS 2 226 #else 227 #define TCP_FASTOPEN_MAX_PSKS TCP_RFC7413_MAX_PSKS 228 #endif 229 230 #if TCP_FASTOPEN_MAX_PSKS > 10 231 #undef TCP_FASTOPEN_MAX_PSKS 232 #define TCP_FASTOPEN_MAX_PSKS 10 233 #endif 234 235 struct tcp_fastopen_keylist { 236 unsigned int newest; 237 unsigned int newest_psk; 238 uint8_t key[TCP_FASTOPEN_MAX_KEYS][TCP_FASTOPEN_KEY_LEN]; 239 uint8_t psk[TCP_FASTOPEN_MAX_PSKS][TCP_FASTOPEN_KEY_LEN]; 240 }; 241 242 struct tcp_fastopen_callout { 243 struct callout c; 244 struct vnet *v; 245 }; 246 247 static struct tcp_fastopen_ccache_entry *tcp_fastopen_ccache_lookup( 248 struct in_conninfo *, struct tcp_fastopen_ccache_bucket **); 249 static struct tcp_fastopen_ccache_entry *tcp_fastopen_ccache_create( 250 struct tcp_fastopen_ccache_bucket *, struct in_conninfo *, uint16_t, uint8_t, 251 uint8_t *); 252 static void tcp_fastopen_ccache_bucket_trim(struct tcp_fastopen_ccache_bucket *, 253 unsigned int); 254 static void tcp_fastopen_ccache_entry_drop(struct tcp_fastopen_ccache_entry *, 255 struct tcp_fastopen_ccache_bucket *); 256 257 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, fastopen, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 258 "TCP Fast Open"); 259 260 VNET_DEFINE_STATIC(int, tcp_fastopen_acceptany) = 0; 261 #define V_tcp_fastopen_acceptany VNET(tcp_fastopen_acceptany) 262 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, acceptany, 263 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_fastopen_acceptany), 0, 264 "Accept any non-empty cookie"); 265 266 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_autokey) = 120; 267 #define V_tcp_fastopen_autokey VNET(tcp_fastopen_autokey) 268 static int sysctl_net_inet_tcp_fastopen_autokey(SYSCTL_HANDLER_ARGS); 269 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, autokey, 270 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 271 NULL, 0, &sysctl_net_inet_tcp_fastopen_autokey, "IU", 272 "Number of seconds between auto-generation of a new key; zero disables"); 273 274 static int sysctl_net_inet_tcp_fastopen_ccache_bucket_limit(SYSCTL_HANDLER_ARGS); 275 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, ccache_bucket_limit, 276 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, 277 NULL, 0, &sysctl_net_inet_tcp_fastopen_ccache_bucket_limit, "IU", 278 "Max entries per bucket in client cookie cache"); 279 280 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_ccache_buckets) = 281 TCP_FASTOPEN_CCACHE_BUCKETS_DEFAULT; 282 #define V_tcp_fastopen_ccache_buckets VNET(tcp_fastopen_ccache_buckets) 283 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, ccache_buckets, 284 CTLFLAG_VNET | CTLFLAG_RDTUN, &VNET_NAME(tcp_fastopen_ccache_buckets), 0, 285 "Client cookie cache number of buckets (power of 2)"); 286 287 VNET_DEFINE(unsigned int, tcp_fastopen_client_enable) = 1; 288 static int sysctl_net_inet_tcp_fastopen_client_enable(SYSCTL_HANDLER_ARGS); 289 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, client_enable, 290 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 291 NULL, 0, &sysctl_net_inet_tcp_fastopen_client_enable, "IU", 292 "Enable/disable TCP Fast Open client functionality"); 293 294 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, keylen, 295 CTLFLAG_RD, SYSCTL_NULL_INT_PTR, TCP_FASTOPEN_KEY_LEN, 296 "Key length in bytes"); 297 298 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, maxkeys, 299 CTLFLAG_RD, SYSCTL_NULL_INT_PTR, TCP_FASTOPEN_MAX_KEYS, 300 "Maximum number of keys supported"); 301 302 SYSCTL_INT(_net_inet_tcp_fastopen, OID_AUTO, maxpsks, 303 CTLFLAG_RD, SYSCTL_NULL_INT_PTR, TCP_FASTOPEN_MAX_PSKS, 304 "Maximum number of pre-shared keys supported"); 305 306 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_numkeys) = 0; 307 #define V_tcp_fastopen_numkeys VNET(tcp_fastopen_numkeys) 308 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, numkeys, 309 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(tcp_fastopen_numkeys), 0, 310 "Number of keys installed"); 311 312 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_numpsks) = 0; 313 #define V_tcp_fastopen_numpsks VNET(tcp_fastopen_numpsks) 314 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, numpsks, 315 CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(tcp_fastopen_numpsks), 0, 316 "Number of pre-shared keys installed"); 317 318 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_path_disable_time) = 319 TCP_FASTOPEN_PATH_DISABLE_TIME_DEFAULT; 320 #define V_tcp_fastopen_path_disable_time VNET(tcp_fastopen_path_disable_time) 321 SYSCTL_UINT(_net_inet_tcp_fastopen, OID_AUTO, path_disable_time, 322 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_fastopen_path_disable_time), 0, 323 "Seconds a TFO failure disables a {client_ip, server_ip, server_port} path"); 324 325 VNET_DEFINE_STATIC(unsigned int, tcp_fastopen_psk_enable) = 0; 326 #define V_tcp_fastopen_psk_enable VNET(tcp_fastopen_psk_enable) 327 static int sysctl_net_inet_tcp_fastopen_psk_enable(SYSCTL_HANDLER_ARGS); 328 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, psk_enable, 329 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 330 NULL, 0, &sysctl_net_inet_tcp_fastopen_psk_enable, "IU", 331 "Enable/disable TCP Fast Open server pre-shared key mode"); 332 333 VNET_DEFINE(unsigned int, tcp_fastopen_server_enable) = 0; 334 static int sysctl_net_inet_tcp_fastopen_server_enable(SYSCTL_HANDLER_ARGS); 335 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, server_enable, 336 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 337 NULL, 0, &sysctl_net_inet_tcp_fastopen_server_enable, "IU", 338 "Enable/disable TCP Fast Open server functionality"); 339 340 static int sysctl_net_inet_tcp_fastopen_setkey(SYSCTL_HANDLER_ARGS); 341 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, setkey, 342 CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_WR | CTLFLAG_MPSAFE, 343 NULL, 0, &sysctl_net_inet_tcp_fastopen_setkey, "", 344 "Install a new key"); 345 346 static int sysctl_net_inet_tcp_fastopen_setpsk(SYSCTL_HANDLER_ARGS); 347 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, setpsk, 348 CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_WR | CTLFLAG_MPSAFE, 349 NULL, 0, &sysctl_net_inet_tcp_fastopen_setpsk, "", 350 "Install a new pre-shared key"); 351 352 static int sysctl_net_inet_tcp_fastopen_ccache_list(SYSCTL_HANDLER_ARGS); 353 SYSCTL_PROC(_net_inet_tcp_fastopen, OID_AUTO, ccache_list, 354 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP | CTLFLAG_MPSAFE, 355 NULL, 0, sysctl_net_inet_tcp_fastopen_ccache_list, "A", 356 "List of all client cookie cache entries"); 357 358 VNET_DEFINE_STATIC(struct rmlock, tcp_fastopen_keylock); 359 #define V_tcp_fastopen_keylock VNET(tcp_fastopen_keylock) 360 361 #define TCP_FASTOPEN_KEYS_RLOCK(t) rm_rlock(&V_tcp_fastopen_keylock, (t)) 362 #define TCP_FASTOPEN_KEYS_RUNLOCK(t) rm_runlock(&V_tcp_fastopen_keylock, (t)) 363 #define TCP_FASTOPEN_KEYS_WLOCK() rm_wlock(&V_tcp_fastopen_keylock) 364 #define TCP_FASTOPEN_KEYS_WUNLOCK() rm_wunlock(&V_tcp_fastopen_keylock) 365 366 VNET_DEFINE_STATIC(struct tcp_fastopen_keylist, tcp_fastopen_keys); 367 #define V_tcp_fastopen_keys VNET(tcp_fastopen_keys) 368 369 VNET_DEFINE_STATIC(struct tcp_fastopen_callout, tcp_fastopen_autokey_ctx); 370 #define V_tcp_fastopen_autokey_ctx VNET(tcp_fastopen_autokey_ctx) 371 372 VNET_DEFINE_STATIC(uma_zone_t, counter_zone); 373 #define V_counter_zone VNET(counter_zone) 374 375 static MALLOC_DEFINE(M_TCP_FASTOPEN_CCACHE, "tfo_ccache", "TFO client cookie cache buckets"); 376 377 VNET_DEFINE_STATIC(struct tcp_fastopen_ccache, tcp_fastopen_ccache); 378 #define V_tcp_fastopen_ccache VNET(tcp_fastopen_ccache) 379 380 #define CCB_LOCK(ccb) mtx_lock(&(ccb)->ccb_mtx) 381 #define CCB_UNLOCK(ccb) mtx_unlock(&(ccb)->ccb_mtx) 382 #define CCB_LOCK_ASSERT(ccb) mtx_assert(&(ccb)->ccb_mtx, MA_OWNED) 383 384 void 385 tcp_fastopen_init(void) 386 { 387 unsigned int i; 388 389 V_counter_zone = uma_zcreate("tfo", sizeof(unsigned int), 390 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 391 rm_init(&V_tcp_fastopen_keylock, "tfo_keylock"); 392 callout_init_rm(&V_tcp_fastopen_autokey_ctx.c, 393 &V_tcp_fastopen_keylock, 0); 394 V_tcp_fastopen_autokey_ctx.v = curvnet; 395 V_tcp_fastopen_keys.newest = TCP_FASTOPEN_MAX_KEYS - 1; 396 V_tcp_fastopen_keys.newest_psk = TCP_FASTOPEN_MAX_PSKS - 1; 397 398 /* May already be non-zero if kernel tunable was set */ 399 if (V_tcp_fastopen_ccache.bucket_limit == 0) 400 V_tcp_fastopen_ccache.bucket_limit = 401 TCP_FASTOPEN_CCACHE_BUCKET_LIMIT_DEFAULT; 402 403 /* May already be non-zero if kernel tunable was set */ 404 if ((V_tcp_fastopen_ccache_buckets == 0) || 405 !powerof2(V_tcp_fastopen_ccache_buckets)) 406 V_tcp_fastopen_ccache.buckets = 407 TCP_FASTOPEN_CCACHE_BUCKETS_DEFAULT; 408 else 409 V_tcp_fastopen_ccache.buckets = V_tcp_fastopen_ccache_buckets; 410 411 V_tcp_fastopen_ccache.mask = V_tcp_fastopen_ccache.buckets - 1; 412 V_tcp_fastopen_ccache.secret = arc4random(); 413 414 V_tcp_fastopen_ccache.base = malloc(V_tcp_fastopen_ccache.buckets * 415 sizeof(struct tcp_fastopen_ccache_bucket), M_TCP_FASTOPEN_CCACHE, 416 M_WAITOK | M_ZERO); 417 418 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 419 TAILQ_INIT(&V_tcp_fastopen_ccache.base[i].ccb_entries); 420 mtx_init(&V_tcp_fastopen_ccache.base[i].ccb_mtx, "tfo_ccache_bucket", 421 NULL, MTX_DEF); 422 if (V_tcp_fastopen_client_enable) { 423 /* enable bucket */ 424 V_tcp_fastopen_ccache.base[i].ccb_num_entries = 0; 425 } else { 426 /* disable bucket */ 427 V_tcp_fastopen_ccache.base[i].ccb_num_entries = -1; 428 } 429 V_tcp_fastopen_ccache.base[i].ccb_ccache = &V_tcp_fastopen_ccache; 430 } 431 432 /* 433 * Note that while the total number of entries in the cookie cache 434 * is limited by the table management logic to 435 * V_tcp_fastopen_ccache.buckets * 436 * V_tcp_fastopen_ccache.bucket_limit, the total number of items in 437 * this zone can exceed that amount by the number of CPUs in the 438 * system times the maximum number of unallocated items that can be 439 * present in each UMA per-CPU cache for this zone. 440 */ 441 V_tcp_fastopen_ccache.zone = uma_zcreate("tfo_ccache_entries", 442 sizeof(struct tcp_fastopen_ccache_entry), NULL, NULL, NULL, NULL, 443 UMA_ALIGN_CACHE, 0); 444 } 445 446 void 447 tcp_fastopen_destroy(void) 448 { 449 struct tcp_fastopen_ccache_bucket *ccb; 450 unsigned int i; 451 452 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 453 ccb = &V_tcp_fastopen_ccache.base[i]; 454 tcp_fastopen_ccache_bucket_trim(ccb, 0); 455 mtx_destroy(&ccb->ccb_mtx); 456 } 457 458 KASSERT(uma_zone_get_cur(V_tcp_fastopen_ccache.zone) == 0, 459 ("%s: TFO ccache zone allocation count not 0", __func__)); 460 uma_zdestroy(V_tcp_fastopen_ccache.zone); 461 free(V_tcp_fastopen_ccache.base, M_TCP_FASTOPEN_CCACHE); 462 463 callout_drain(&V_tcp_fastopen_autokey_ctx.c); 464 rm_destroy(&V_tcp_fastopen_keylock); 465 uma_zdestroy(V_counter_zone); 466 } 467 468 unsigned int * 469 tcp_fastopen_alloc_counter(void) 470 { 471 unsigned int *counter; 472 counter = uma_zalloc(V_counter_zone, M_NOWAIT); 473 if (counter) 474 *counter = 1; 475 return (counter); 476 } 477 478 void 479 tcp_fastopen_decrement_counter(unsigned int *counter) 480 { 481 if (*counter == 1) 482 uma_zfree(V_counter_zone, counter); 483 else 484 atomic_subtract_int(counter, 1); 485 } 486 487 static void 488 tcp_fastopen_addkey_locked(uint8_t *key) 489 { 490 491 V_tcp_fastopen_keys.newest++; 492 if (V_tcp_fastopen_keys.newest == TCP_FASTOPEN_MAX_KEYS) 493 V_tcp_fastopen_keys.newest = 0; 494 memcpy(V_tcp_fastopen_keys.key[V_tcp_fastopen_keys.newest], key, 495 TCP_FASTOPEN_KEY_LEN); 496 if (V_tcp_fastopen_numkeys < TCP_FASTOPEN_MAX_KEYS) 497 V_tcp_fastopen_numkeys++; 498 } 499 500 static void 501 tcp_fastopen_addpsk_locked(uint8_t *psk) 502 { 503 504 V_tcp_fastopen_keys.newest_psk++; 505 if (V_tcp_fastopen_keys.newest_psk == TCP_FASTOPEN_MAX_PSKS) 506 V_tcp_fastopen_keys.newest_psk = 0; 507 memcpy(V_tcp_fastopen_keys.psk[V_tcp_fastopen_keys.newest_psk], psk, 508 TCP_FASTOPEN_KEY_LEN); 509 if (V_tcp_fastopen_numpsks < TCP_FASTOPEN_MAX_PSKS) 510 V_tcp_fastopen_numpsks++; 511 } 512 513 static void 514 tcp_fastopen_autokey_locked(void) 515 { 516 uint8_t newkey[TCP_FASTOPEN_KEY_LEN]; 517 518 arc4rand(newkey, TCP_FASTOPEN_KEY_LEN, 0); 519 tcp_fastopen_addkey_locked(newkey); 520 } 521 522 static void 523 tcp_fastopen_autokey_callout(void *arg) 524 { 525 struct tcp_fastopen_callout *ctx = arg; 526 527 CURVNET_SET(ctx->v); 528 tcp_fastopen_autokey_locked(); 529 callout_reset(&ctx->c, V_tcp_fastopen_autokey * hz, 530 tcp_fastopen_autokey_callout, ctx); 531 CURVNET_RESTORE(); 532 } 533 534 static uint64_t 535 tcp_fastopen_make_cookie(uint8_t key[SIPHASH_KEY_LENGTH], struct in_conninfo *inc) 536 { 537 SIPHASH_CTX ctx; 538 uint64_t siphash; 539 540 SipHash24_Init(&ctx); 541 SipHash_SetKey(&ctx, key); 542 switch (inc->inc_flags & INC_ISIPV6) { 543 #ifdef INET 544 case 0: 545 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(inc->inc_faddr)); 546 break; 547 #endif 548 #ifdef INET6 549 case INC_ISIPV6: 550 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(inc->inc6_faddr)); 551 break; 552 #endif 553 } 554 SipHash_Final((u_int8_t *)&siphash, &ctx); 555 556 return (siphash); 557 } 558 559 static uint64_t 560 tcp_fastopen_make_psk_cookie(uint8_t *psk, uint8_t *cookie, uint8_t cookie_len) 561 { 562 SIPHASH_CTX ctx; 563 uint64_t psk_cookie; 564 565 SipHash24_Init(&ctx); 566 SipHash_SetKey(&ctx, psk); 567 SipHash_Update(&ctx, cookie, cookie_len); 568 SipHash_Final((u_int8_t *)&psk_cookie, &ctx); 569 570 return (psk_cookie); 571 } 572 573 static int 574 tcp_fastopen_find_cookie_match_locked(uint8_t *wire_cookie, uint64_t *cur_cookie) 575 { 576 unsigned int i, psk_index; 577 uint64_t psk_cookie; 578 579 if (V_tcp_fastopen_psk_enable) { 580 psk_index = V_tcp_fastopen_keys.newest_psk; 581 for (i = 0; i < V_tcp_fastopen_numpsks; i++) { 582 psk_cookie = 583 tcp_fastopen_make_psk_cookie( 584 V_tcp_fastopen_keys.psk[psk_index], 585 (uint8_t *)cur_cookie, 586 TCP_FASTOPEN_COOKIE_LEN); 587 588 if (memcmp(wire_cookie, &psk_cookie, 589 TCP_FASTOPEN_COOKIE_LEN) == 0) 590 return (1); 591 592 if (psk_index == 0) 593 psk_index = TCP_FASTOPEN_MAX_PSKS - 1; 594 else 595 psk_index--; 596 } 597 } else if (memcmp(wire_cookie, cur_cookie, TCP_FASTOPEN_COOKIE_LEN) == 0) 598 return (1); 599 600 return (0); 601 } 602 603 /* 604 * Return values: 605 * -1 the cookie is invalid and no valid cookie is available 606 * 0 the cookie is invalid and the latest cookie has been returned 607 * 1 the cookie is valid and the latest cookie has been returned 608 */ 609 int 610 tcp_fastopen_check_cookie(struct in_conninfo *inc, uint8_t *cookie, 611 unsigned int len, uint64_t *latest_cookie) 612 { 613 struct rm_priotracker tracker; 614 unsigned int i, key_index; 615 int rv; 616 uint64_t cur_cookie; 617 618 if (V_tcp_fastopen_acceptany) { 619 *latest_cookie = 0; 620 return (1); 621 } 622 623 TCP_FASTOPEN_KEYS_RLOCK(&tracker); 624 if (len != TCP_FASTOPEN_COOKIE_LEN) { 625 if (V_tcp_fastopen_numkeys > 0) { 626 *latest_cookie = 627 tcp_fastopen_make_cookie( 628 V_tcp_fastopen_keys.key[V_tcp_fastopen_keys.newest], 629 inc); 630 rv = 0; 631 } else 632 rv = -1; 633 goto out; 634 } 635 636 /* 637 * Check against each available key, from newest to oldest. 638 */ 639 key_index = V_tcp_fastopen_keys.newest; 640 for (i = 0; i < V_tcp_fastopen_numkeys; i++) { 641 cur_cookie = 642 tcp_fastopen_make_cookie(V_tcp_fastopen_keys.key[key_index], 643 inc); 644 if (i == 0) 645 *latest_cookie = cur_cookie; 646 rv = tcp_fastopen_find_cookie_match_locked(cookie, &cur_cookie); 647 if (rv) 648 goto out; 649 if (key_index == 0) 650 key_index = TCP_FASTOPEN_MAX_KEYS - 1; 651 else 652 key_index--; 653 } 654 rv = 0; 655 656 out: 657 TCP_FASTOPEN_KEYS_RUNLOCK(&tracker); 658 return (rv); 659 } 660 661 static int 662 sysctl_net_inet_tcp_fastopen_autokey(SYSCTL_HANDLER_ARGS) 663 { 664 int error; 665 unsigned int new; 666 667 new = V_tcp_fastopen_autokey; 668 error = sysctl_handle_int(oidp, &new, 0, req); 669 if (error == 0 && req->newptr) { 670 if (new > (INT_MAX / hz)) 671 return (EINVAL); 672 673 TCP_FASTOPEN_KEYS_WLOCK(); 674 if (V_tcp_fastopen_server_enable) { 675 if (V_tcp_fastopen_autokey && !new) 676 callout_stop(&V_tcp_fastopen_autokey_ctx.c); 677 else if (new) 678 callout_reset(&V_tcp_fastopen_autokey_ctx.c, 679 new * hz, tcp_fastopen_autokey_callout, 680 &V_tcp_fastopen_autokey_ctx); 681 } 682 V_tcp_fastopen_autokey = new; 683 TCP_FASTOPEN_KEYS_WUNLOCK(); 684 } 685 686 return (error); 687 } 688 689 static int 690 sysctl_net_inet_tcp_fastopen_psk_enable(SYSCTL_HANDLER_ARGS) 691 { 692 int error; 693 unsigned int new; 694 695 new = V_tcp_fastopen_psk_enable; 696 error = sysctl_handle_int(oidp, &new, 0, req); 697 if (error == 0 && req->newptr) { 698 if (V_tcp_fastopen_psk_enable && !new) { 699 /* enabled -> disabled */ 700 TCP_FASTOPEN_KEYS_WLOCK(); 701 V_tcp_fastopen_numpsks = 0; 702 V_tcp_fastopen_keys.newest_psk = 703 TCP_FASTOPEN_MAX_PSKS - 1; 704 V_tcp_fastopen_psk_enable = 0; 705 TCP_FASTOPEN_KEYS_WUNLOCK(); 706 } else if (!V_tcp_fastopen_psk_enable && new) { 707 /* disabled -> enabled */ 708 TCP_FASTOPEN_KEYS_WLOCK(); 709 V_tcp_fastopen_psk_enable = 1; 710 TCP_FASTOPEN_KEYS_WUNLOCK(); 711 } 712 } 713 return (error); 714 } 715 716 static int 717 sysctl_net_inet_tcp_fastopen_server_enable(SYSCTL_HANDLER_ARGS) 718 { 719 int error; 720 unsigned int new; 721 722 new = V_tcp_fastopen_server_enable; 723 error = sysctl_handle_int(oidp, &new, 0, req); 724 if (error == 0 && req->newptr) { 725 if (V_tcp_fastopen_server_enable && !new) { 726 /* enabled -> disabled */ 727 TCP_FASTOPEN_KEYS_WLOCK(); 728 V_tcp_fastopen_numkeys = 0; 729 V_tcp_fastopen_keys.newest = TCP_FASTOPEN_MAX_KEYS - 1; 730 if (V_tcp_fastopen_autokey) 731 callout_stop(&V_tcp_fastopen_autokey_ctx.c); 732 V_tcp_fastopen_numpsks = 0; 733 V_tcp_fastopen_keys.newest_psk = 734 TCP_FASTOPEN_MAX_PSKS - 1; 735 V_tcp_fastopen_server_enable = 0; 736 TCP_FASTOPEN_KEYS_WUNLOCK(); 737 } else if (!V_tcp_fastopen_server_enable && new) { 738 /* disabled -> enabled */ 739 TCP_FASTOPEN_KEYS_WLOCK(); 740 if (V_tcp_fastopen_autokey && 741 (V_tcp_fastopen_numkeys == 0)) { 742 tcp_fastopen_autokey_locked(); 743 callout_reset(&V_tcp_fastopen_autokey_ctx.c, 744 V_tcp_fastopen_autokey * hz, 745 tcp_fastopen_autokey_callout, 746 &V_tcp_fastopen_autokey_ctx); 747 } 748 V_tcp_fastopen_server_enable = 1; 749 TCP_FASTOPEN_KEYS_WUNLOCK(); 750 } 751 } 752 return (error); 753 } 754 755 static int 756 sysctl_net_inet_tcp_fastopen_setkey(SYSCTL_HANDLER_ARGS) 757 { 758 int error; 759 uint8_t newkey[TCP_FASTOPEN_KEY_LEN]; 760 761 if (req->oldptr != NULL || req->oldlen != 0) 762 return (EINVAL); 763 if (req->newptr == NULL) 764 return (EPERM); 765 if (req->newlen != sizeof(newkey)) 766 return (EINVAL); 767 error = SYSCTL_IN(req, newkey, sizeof(newkey)); 768 if (error) 769 return (error); 770 771 TCP_FASTOPEN_KEYS_WLOCK(); 772 tcp_fastopen_addkey_locked(newkey); 773 TCP_FASTOPEN_KEYS_WUNLOCK(); 774 775 return (0); 776 } 777 778 static int 779 sysctl_net_inet_tcp_fastopen_setpsk(SYSCTL_HANDLER_ARGS) 780 { 781 int error; 782 uint8_t newpsk[TCP_FASTOPEN_KEY_LEN]; 783 784 if (req->oldptr != NULL || req->oldlen != 0) 785 return (EINVAL); 786 if (req->newptr == NULL) 787 return (EPERM); 788 if (req->newlen != sizeof(newpsk)) 789 return (EINVAL); 790 error = SYSCTL_IN(req, newpsk, sizeof(newpsk)); 791 if (error) 792 return (error); 793 794 TCP_FASTOPEN_KEYS_WLOCK(); 795 tcp_fastopen_addpsk_locked(newpsk); 796 TCP_FASTOPEN_KEYS_WUNLOCK(); 797 798 return (0); 799 } 800 801 static int 802 sysctl_net_inet_tcp_fastopen_ccache_bucket_limit(SYSCTL_HANDLER_ARGS) 803 { 804 struct tcp_fastopen_ccache_bucket *ccb; 805 int error; 806 unsigned int new; 807 unsigned int i; 808 809 new = V_tcp_fastopen_ccache.bucket_limit; 810 error = sysctl_handle_int(oidp, &new, 0, req); 811 if (error == 0 && req->newptr) { 812 if ((new == 0) || (new > INT_MAX)) 813 error = EINVAL; 814 else { 815 if (new < V_tcp_fastopen_ccache.bucket_limit) { 816 for (i = 0; i < V_tcp_fastopen_ccache.buckets; 817 i++) { 818 ccb = &V_tcp_fastopen_ccache.base[i]; 819 tcp_fastopen_ccache_bucket_trim(ccb, new); 820 } 821 } 822 V_tcp_fastopen_ccache.bucket_limit = new; 823 } 824 } 825 return (error); 826 } 827 828 static int 829 sysctl_net_inet_tcp_fastopen_client_enable(SYSCTL_HANDLER_ARGS) 830 { 831 struct tcp_fastopen_ccache_bucket *ccb; 832 int error; 833 unsigned int new, i; 834 835 new = V_tcp_fastopen_client_enable; 836 error = sysctl_handle_int(oidp, &new, 0, req); 837 if (error == 0 && req->newptr) { 838 if (V_tcp_fastopen_client_enable && !new) { 839 /* enabled -> disabled */ 840 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 841 ccb = &V_tcp_fastopen_ccache.base[i]; 842 KASSERT(ccb->ccb_num_entries > -1, 843 ("%s: ccb->ccb_num_entries %d is negative", 844 __func__, ccb->ccb_num_entries)); 845 tcp_fastopen_ccache_bucket_trim(ccb, 0); 846 } 847 V_tcp_fastopen_client_enable = 0; 848 } else if (!V_tcp_fastopen_client_enable && new) { 849 /* disabled -> enabled */ 850 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 851 ccb = &V_tcp_fastopen_ccache.base[i]; 852 CCB_LOCK(ccb); 853 KASSERT(TAILQ_EMPTY(&ccb->ccb_entries), 854 ("%s: ccb->ccb_entries not empty", __func__)); 855 KASSERT(ccb->ccb_num_entries == -1, 856 ("%s: ccb->ccb_num_entries %d not -1", __func__, 857 ccb->ccb_num_entries)); 858 ccb->ccb_num_entries = 0; /* enable bucket */ 859 CCB_UNLOCK(ccb); 860 } 861 V_tcp_fastopen_client_enable = 1; 862 } 863 } 864 return (error); 865 } 866 867 void 868 tcp_fastopen_connect(struct tcpcb *tp) 869 { 870 struct inpcb *inp = tptoinpcb(tp); 871 struct tcp_fastopen_ccache_bucket *ccb; 872 struct tcp_fastopen_ccache_entry *cce; 873 sbintime_t now; 874 uint16_t server_mss; 875 uint64_t psk_cookie; 876 877 psk_cookie = 0; 878 cce = tcp_fastopen_ccache_lookup(&inp->inp_inc, &ccb); 879 if (cce) { 880 if (cce->disable_time == 0) { 881 if ((cce->cookie_len > 0) && 882 (tp->t_tfo_client_cookie_len == 883 TCP_FASTOPEN_PSK_LEN)) { 884 psk_cookie = 885 tcp_fastopen_make_psk_cookie( 886 tp->t_tfo_cookie.client, 887 cce->cookie, cce->cookie_len); 888 } else { 889 tp->t_tfo_client_cookie_len = cce->cookie_len; 890 memcpy(tp->t_tfo_cookie.client, cce->cookie, 891 cce->cookie_len); 892 } 893 server_mss = cce->server_mss; 894 CCB_UNLOCK(ccb); 895 if (tp->t_tfo_client_cookie_len == 896 TCP_FASTOPEN_PSK_LEN && psk_cookie) { 897 tp->t_tfo_client_cookie_len = 898 TCP_FASTOPEN_COOKIE_LEN; 899 memcpy(tp->t_tfo_cookie.client, &psk_cookie, 900 TCP_FASTOPEN_COOKIE_LEN); 901 } 902 tcp_mss(tp, server_mss ? server_mss : -1); 903 tp->snd_wnd = tp->t_maxseg; 904 } else { 905 /* 906 * The path is disabled. Check the time and 907 * possibly re-enable. 908 */ 909 now = getsbinuptime(); 910 if (now - cce->disable_time > 911 ((sbintime_t)V_tcp_fastopen_path_disable_time << 32)) { 912 /* 913 * Re-enable path. Force a TFO cookie 914 * request. Forget the old MSS as it may be 915 * bogus now, and we will rediscover it in 916 * the SYN|ACK. 917 */ 918 cce->disable_time = 0; 919 cce->server_mss = 0; 920 cce->cookie_len = 0; 921 /* 922 * tp->t_tfo... cookie details are already 923 * zero from the tcpcb init. 924 */ 925 } else { 926 /* 927 * Path is disabled, so disable TFO on this 928 * connection. 929 */ 930 tp->t_flags &= ~TF_FASTOPEN; 931 } 932 CCB_UNLOCK(ccb); 933 tcp_mss(tp, -1); 934 /* 935 * snd_wnd is irrelevant since we are either forcing 936 * a TFO cookie request or disabling TFO - either 937 * way, no data with the SYN. 938 */ 939 } 940 } else { 941 /* 942 * A new entry for this path will be created when a SYN|ACK 943 * comes back, or the attempt otherwise fails. 944 */ 945 CCB_UNLOCK(ccb); 946 tcp_mss(tp, -1); 947 /* 948 * snd_wnd is irrelevant since we are forcing a TFO cookie 949 * request. 950 */ 951 } 952 } 953 954 void 955 tcp_fastopen_disable_path(struct tcpcb *tp) 956 { 957 struct in_conninfo *inc = &tptoinpcb(tp)->inp_inc; 958 struct tcp_fastopen_ccache_bucket *ccb; 959 struct tcp_fastopen_ccache_entry *cce; 960 961 cce = tcp_fastopen_ccache_lookup(inc, &ccb); 962 if (cce) { 963 cce->server_mss = 0; 964 cce->cookie_len = 0; 965 /* 966 * Preserve the existing disable time if it is already 967 * disabled. 968 */ 969 if (cce->disable_time == 0) 970 cce->disable_time = getsbinuptime(); 971 } else /* use invalid cookie len to create disabled entry */ 972 tcp_fastopen_ccache_create(ccb, inc, 0, 973 TCP_FASTOPEN_MAX_COOKIE_LEN + 1, NULL); 974 975 CCB_UNLOCK(ccb); 976 tp->t_flags &= ~TF_FASTOPEN; 977 } 978 979 void 980 tcp_fastopen_update_cache(struct tcpcb *tp, uint16_t mss, 981 uint8_t cookie_len, uint8_t *cookie) 982 { 983 struct in_conninfo *inc = &tptoinpcb(tp)->inp_inc; 984 struct tcp_fastopen_ccache_bucket *ccb; 985 struct tcp_fastopen_ccache_entry *cce; 986 987 cce = tcp_fastopen_ccache_lookup(inc, &ccb); 988 if (cce) { 989 if ((cookie_len >= TCP_FASTOPEN_MIN_COOKIE_LEN) && 990 (cookie_len <= TCP_FASTOPEN_MAX_COOKIE_LEN) && 991 ((cookie_len & 0x1) == 0)) { 992 cce->server_mss = mss; 993 cce->cookie_len = cookie_len; 994 memcpy(cce->cookie, cookie, cookie_len); 995 cce->disable_time = 0; 996 } else { 997 /* invalid cookie length, disable entry */ 998 cce->server_mss = 0; 999 cce->cookie_len = 0; 1000 /* 1001 * Preserve the existing disable time if it is 1002 * already disabled. 1003 */ 1004 if (cce->disable_time == 0) 1005 cce->disable_time = getsbinuptime(); 1006 } 1007 } else 1008 tcp_fastopen_ccache_create(ccb, inc, mss, cookie_len, cookie); 1009 1010 CCB_UNLOCK(ccb); 1011 } 1012 1013 static struct tcp_fastopen_ccache_entry * 1014 tcp_fastopen_ccache_lookup(struct in_conninfo *inc, 1015 struct tcp_fastopen_ccache_bucket **ccbp) 1016 { 1017 struct tcp_fastopen_ccache_bucket *ccb; 1018 struct tcp_fastopen_ccache_entry *cce; 1019 uint32_t last_word; 1020 uint32_t hash; 1021 1022 hash = jenkins_hash32((uint32_t *)&inc->inc_ie.ie_dependladdr, 4, 1023 V_tcp_fastopen_ccache.secret); 1024 hash = jenkins_hash32((uint32_t *)&inc->inc_ie.ie_dependfaddr, 4, 1025 hash); 1026 last_word = inc->inc_fport; 1027 hash = jenkins_hash32(&last_word, 1, hash); 1028 ccb = &V_tcp_fastopen_ccache.base[hash & V_tcp_fastopen_ccache.mask]; 1029 *ccbp = ccb; 1030 CCB_LOCK(ccb); 1031 1032 /* 1033 * Always returns with locked bucket. 1034 */ 1035 TAILQ_FOREACH(cce, &ccb->ccb_entries, cce_link) 1036 if ((!(cce->af == AF_INET6) == !(inc->inc_flags & INC_ISIPV6)) && 1037 (cce->server_port == inc->inc_ie.ie_fport) && 1038 (((cce->af == AF_INET) && 1039 (cce->cce_client_ip.v4.s_addr == inc->inc_laddr.s_addr) && 1040 (cce->cce_server_ip.v4.s_addr == inc->inc_faddr.s_addr)) || 1041 ((cce->af == AF_INET6) && 1042 IN6_ARE_ADDR_EQUAL(&cce->cce_client_ip.v6, &inc->inc6_laddr) && 1043 IN6_ARE_ADDR_EQUAL(&cce->cce_server_ip.v6, &inc->inc6_faddr)))) 1044 break; 1045 1046 return (cce); 1047 } 1048 1049 static struct tcp_fastopen_ccache_entry * 1050 tcp_fastopen_ccache_create(struct tcp_fastopen_ccache_bucket *ccb, 1051 struct in_conninfo *inc, uint16_t mss, uint8_t cookie_len, uint8_t *cookie) 1052 { 1053 struct tcp_fastopen_ccache_entry *cce; 1054 1055 /* 1056 * 1. Create a new entry, or 1057 * 2. Reclaim an existing entry, or 1058 * 3. Fail 1059 */ 1060 1061 CCB_LOCK_ASSERT(ccb); 1062 1063 cce = NULL; 1064 if (ccb->ccb_num_entries < V_tcp_fastopen_ccache.bucket_limit) 1065 cce = uma_zalloc(V_tcp_fastopen_ccache.zone, M_NOWAIT); 1066 1067 if (cce == NULL) { 1068 /* 1069 * At bucket limit, or out of memory - reclaim last 1070 * entry in bucket. 1071 */ 1072 cce = TAILQ_LAST(&ccb->ccb_entries, bucket_entries); 1073 if (cce == NULL) { 1074 /* XXX count this event */ 1075 return (NULL); 1076 } 1077 1078 TAILQ_REMOVE(&ccb->ccb_entries, cce, cce_link); 1079 } else 1080 ccb->ccb_num_entries++; 1081 1082 TAILQ_INSERT_HEAD(&ccb->ccb_entries, cce, cce_link); 1083 cce->af = (inc->inc_flags & INC_ISIPV6) ? AF_INET6 : AF_INET; 1084 if (cce->af == AF_INET) { 1085 cce->cce_client_ip.v4 = inc->inc_laddr; 1086 cce->cce_server_ip.v4 = inc->inc_faddr; 1087 } else { 1088 cce->cce_client_ip.v6 = inc->inc6_laddr; 1089 cce->cce_server_ip.v6 = inc->inc6_faddr; 1090 } 1091 cce->server_port = inc->inc_fport; 1092 if ((cookie_len >= TCP_FASTOPEN_MIN_COOKIE_LEN) && 1093 (cookie_len <= TCP_FASTOPEN_MAX_COOKIE_LEN) && 1094 ((cookie_len & 0x1) == 0)) { 1095 cce->server_mss = mss; 1096 cce->cookie_len = cookie_len; 1097 memcpy(cce->cookie, cookie, cookie_len); 1098 cce->disable_time = 0; 1099 } else { 1100 /* invalid cookie length, disable cce */ 1101 cce->server_mss = 0; 1102 cce->cookie_len = 0; 1103 cce->disable_time = getsbinuptime(); 1104 } 1105 1106 return (cce); 1107 } 1108 1109 static void 1110 tcp_fastopen_ccache_bucket_trim(struct tcp_fastopen_ccache_bucket *ccb, 1111 unsigned int limit) 1112 { 1113 struct tcp_fastopen_ccache_entry *cce, *cce_tmp; 1114 unsigned int entries; 1115 1116 CCB_LOCK(ccb); 1117 entries = 0; 1118 TAILQ_FOREACH_SAFE(cce, &ccb->ccb_entries, cce_link, cce_tmp) { 1119 entries++; 1120 if (entries > limit) 1121 tcp_fastopen_ccache_entry_drop(cce, ccb); 1122 } 1123 KASSERT(ccb->ccb_num_entries <= (int)limit, 1124 ("%s: ccb->ccb_num_entries %d exceeds limit %d", __func__, 1125 ccb->ccb_num_entries, limit)); 1126 if (limit == 0) { 1127 KASSERT(TAILQ_EMPTY(&ccb->ccb_entries), 1128 ("%s: ccb->ccb_entries not empty", __func__)); 1129 ccb->ccb_num_entries = -1; /* disable bucket */ 1130 } 1131 CCB_UNLOCK(ccb); 1132 } 1133 1134 static void 1135 tcp_fastopen_ccache_entry_drop(struct tcp_fastopen_ccache_entry *cce, 1136 struct tcp_fastopen_ccache_bucket *ccb) 1137 { 1138 1139 CCB_LOCK_ASSERT(ccb); 1140 1141 TAILQ_REMOVE(&ccb->ccb_entries, cce, cce_link); 1142 ccb->ccb_num_entries--; 1143 uma_zfree(V_tcp_fastopen_ccache.zone, cce); 1144 } 1145 1146 static int 1147 sysctl_net_inet_tcp_fastopen_ccache_list(SYSCTL_HANDLER_ARGS) 1148 { 1149 struct sbuf sb; 1150 struct tcp_fastopen_ccache_bucket *ccb; 1151 struct tcp_fastopen_ccache_entry *cce; 1152 sbintime_t now, duration, limit; 1153 const int linesize = 128; 1154 int i, error, num_entries; 1155 unsigned int j; 1156 #ifdef INET6 1157 char clt_buf[INET6_ADDRSTRLEN], srv_buf[INET6_ADDRSTRLEN]; 1158 #else 1159 char clt_buf[INET_ADDRSTRLEN], srv_buf[INET_ADDRSTRLEN]; 1160 #endif 1161 1162 if (jailed_without_vnet(curthread->td_ucred) != 0) 1163 return (EPERM); 1164 1165 /* Only allow root to read the client cookie cache */ 1166 if (curthread->td_ucred->cr_uid != 0) 1167 return (EPERM); 1168 1169 num_entries = 0; 1170 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 1171 ccb = &V_tcp_fastopen_ccache.base[i]; 1172 CCB_LOCK(ccb); 1173 if (ccb->ccb_num_entries > 0) 1174 num_entries += ccb->ccb_num_entries; 1175 CCB_UNLOCK(ccb); 1176 } 1177 sbuf_new(&sb, NULL, linesize * (num_entries + 1), SBUF_INCLUDENUL); 1178 1179 sbuf_printf(&sb, 1180 "\nLocal IP address Remote IP address Port MSS" 1181 " Disabled Cookie\n"); 1182 1183 now = getsbinuptime(); 1184 limit = (sbintime_t)V_tcp_fastopen_path_disable_time << 32; 1185 for (i = 0; i < V_tcp_fastopen_ccache.buckets; i++) { 1186 ccb = &V_tcp_fastopen_ccache.base[i]; 1187 CCB_LOCK(ccb); 1188 TAILQ_FOREACH(cce, &ccb->ccb_entries, cce_link) { 1189 if (cce->disable_time != 0) { 1190 duration = now - cce->disable_time; 1191 if (limit >= duration) 1192 duration = limit - duration; 1193 else 1194 duration = 0; 1195 } else 1196 duration = 0; 1197 sbuf_printf(&sb, 1198 "%-20s %-20s %5u %5u ", 1199 inet_ntop(cce->af, &cce->cce_client_ip, 1200 clt_buf, sizeof(clt_buf)), 1201 inet_ntop(cce->af, &cce->cce_server_ip, 1202 srv_buf, sizeof(srv_buf)), 1203 ntohs(cce->server_port), 1204 cce->server_mss); 1205 if (duration > 0) 1206 sbuf_printf(&sb, "%7ds ", sbintime_getsec(duration)); 1207 else 1208 sbuf_printf(&sb, "%8s ", "No"); 1209 for (j = 0; j < cce->cookie_len; j++) 1210 sbuf_printf(&sb, "%02x", cce->cookie[j]); 1211 sbuf_putc(&sb, '\n'); 1212 } 1213 CCB_UNLOCK(ccb); 1214 } 1215 error = sbuf_finish(&sb); 1216 if (error == 0) 1217 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 1218 sbuf_delete(&sb); 1219 return (error); 1220 }
Cache object: 73160e5e00375c73441b7c0ece9ae30e
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