if_wg.c revision 1.90
1 /* $NetBSD: if_wg.c,v 1.90 2024/07/25 01:47:00 christos Exp $ */ 2 3 /* 4 * Copyright (C) Ryota Ozaki <ozaki.ryota (at) gmail.com> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * This network interface aims to implement the WireGuard protocol. 34 * The implementation is based on the paper of WireGuard as of 35 * 2018-06-30 [1]. The paper is referred in the source code with label 36 * [W]. Also the specification of the Noise protocol framework as of 37 * 2018-07-11 [2] is referred with label [N]. 38 * 39 * [1] https://www.wireguard.com/papers/wireguard.pdf 40 * [2] http://noiseprotocol.org/noise.pdf 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: if_wg.c,v 1.90 2024/07/25 01:47:00 christos Exp $"); 45 46 #ifdef _KERNEL_OPT 47 #include "opt_altq_enabled.h" 48 #include "opt_inet.h" 49 #endif 50 51 #include <sys/param.h> 52 #include <sys/types.h> 53 54 #include <sys/atomic.h> 55 #include <sys/callout.h> 56 #include <sys/cprng.h> 57 #include <sys/cpu.h> 58 #include <sys/device.h> 59 #include <sys/domain.h> 60 #include <sys/errno.h> 61 #include <sys/intr.h> 62 #include <sys/ioctl.h> 63 #include <sys/kernel.h> 64 #include <sys/kmem.h> 65 #include <sys/mbuf.h> 66 #include <sys/module.h> 67 #include <sys/mutex.h> 68 #include <sys/once.h> 69 #include <sys/percpu.h> 70 #include <sys/pserialize.h> 71 #include <sys/psref.h> 72 #include <sys/queue.h> 73 #include <sys/rwlock.h> 74 #include <sys/socket.h> 75 #include <sys/socketvar.h> 76 #include <sys/sockio.h> 77 #include <sys/sysctl.h> 78 #include <sys/syslog.h> 79 #include <sys/systm.h> 80 #include <sys/thmap.h> 81 #include <sys/threadpool.h> 82 #include <sys/time.h> 83 #include <sys/timespec.h> 84 #include <sys/workqueue.h> 85 86 #include <lib/libkern/libkern.h> 87 88 #include <net/bpf.h> 89 #include <net/if.h> 90 #include <net/if_types.h> 91 #include <net/if_wg.h> 92 #include <net/pktqueue.h> 93 #include <net/route.h> 94 95 #include <netinet/in.h> 96 #include <netinet/in_pcb.h> 97 #include <netinet/in_var.h> 98 #include <netinet/ip.h> 99 #include <netinet/ip_var.h> 100 #include <netinet/udp.h> 101 #include <netinet/udp_var.h> 102 103 #ifdef INET6 104 #include <netinet/ip6.h> 105 #include <netinet6/in6_pcb.h> 106 #include <netinet6/in6_var.h> 107 #include <netinet6/ip6_var.h> 108 #include <netinet6/udp6_var.h> 109 #endif /* INET6 */ 110 111 #include <prop/proplib.h> 112 113 #include <crypto/blake2/blake2s.h> 114 #include <crypto/sodium/crypto_aead_chacha20poly1305.h> 115 #include <crypto/sodium/crypto_aead_xchacha20poly1305.h> 116 #include <crypto/sodium/crypto_scalarmult.h> 117 118 #include "ioconf.h" 119 120 #ifdef WG_RUMPKERNEL 121 #include "wg_user.h" 122 #endif 123 124 /* 125 * Data structures 126 * - struct wg_softc is an instance of wg interfaces 127 * - It has a list of peers (struct wg_peer) 128 * - It has a threadpool job that sends/receives handshake messages and 129 * runs event handlers 130 * - It has its own two routing tables: one is for IPv4 and the other IPv6 131 * - struct wg_peer is a representative of a peer 132 * - It has a struct work to handle handshakes and timer tasks 133 * - It has a pair of session instances (struct wg_session) 134 * - It has a pair of endpoint instances (struct wg_sockaddr) 135 * - Normally one endpoint is used and the second one is used only on 136 * a peer migration (a change of peer's IP address) 137 * - It has a list of IP addresses and sub networks called allowedips 138 * (struct wg_allowedip) 139 * - A packets sent over a session is allowed if its destination matches 140 * any IP addresses or sub networks of the list 141 * - struct wg_session represents a session of a secure tunnel with a peer 142 * - Two instances of sessions belong to a peer; a stable session and a 143 * unstable session 144 * - A handshake process of a session always starts with a unstable instance 145 * - Once a session is established, its instance becomes stable and the 146 * other becomes unstable instead 147 * - Data messages are always sent via a stable session 148 * 149 * Locking notes: 150 * - Each wg has a mutex(9) wg_lock, and a rwlock(9) wg_rwlock 151 * - Changes to the peer list are serialized by wg_lock 152 * - The peer list may be read with pserialize(9) and psref(9) 153 * - The rwlock (wg_rwlock) protects the routing tables (wg_rtable_ipv[46]) 154 * => XXX replace by pserialize when routing table is psz-safe 155 * - Each peer (struct wg_peer, wgp) has a mutex wgp_lock, which can be taken 156 * only in thread context and serializes: 157 * - the stable and unstable session pointers 158 * - all unstable session state 159 * - Packet processing may be done in softint context: 160 * - The stable session can be read under pserialize(9) or psref(9) 161 * - The stable session is always ESTABLISHED 162 * - On a session swap, we must wait for all readers to release a 163 * reference to a stable session before changing wgs_state and 164 * session states 165 * - Lock order: wg_lock -> wgp_lock 166 */ 167 168 169 #define WGLOG(level, fmt, args...) \ 170 log(level, "%s: " fmt, __func__, ##args) 171 172 #define WG_DEBUG 173 174 /* Debug options */ 175 #ifdef WG_DEBUG 176 /* Output debug logs */ 177 #ifndef WG_DEBUG_LOG 178 #define WG_DEBUG_LOG 179 #endif 180 /* Output trace logs */ 181 #ifndef WG_DEBUG_TRACE 182 #define WG_DEBUG_TRACE 183 #endif 184 /* Output hash values, etc. */ 185 #ifndef WG_DEBUG_DUMP 186 #define WG_DEBUG_DUMP 187 #endif 188 /* debug packets */ 189 #ifndef WG_DEBUG_PACKET 190 #define WG_DEBUG_PACKET 191 #endif 192 /* Make some internal parameters configurable for testing and debugging */ 193 #ifndef WG_DEBUG_PARAMS 194 #define WG_DEBUG_PARAMS 195 #endif 196 #endif /* WG_DEBUG */ 197 198 #ifndef WG_DEBUG 199 # if defined(WG_DEBUG_LOG) || defined(WG_DEBUG_TRACE) || \ 200 defined(WG_DEBUG_DUMP) || defined(WG_DEBUG_PARAMS) || \ 201 defined(WG_DEBUG_PACKET) 202 # define WG_DEBUG 203 # endif 204 #endif 205 206 #ifdef WG_DEBUG 207 int wg_debug; 208 #define WG_DEBUG_FLAGS_LOG 1 209 #define WG_DEBUG_FLAGS_TRACE 2 210 #define WG_DEBUG_FLAGS_DUMP 4 211 #define WG_DEBUG_FLAGS_PACKET 8 212 #endif 213 214 215 #ifdef WG_DEBUG_TRACE 216 #define WG_TRACE(msg) do { \ 217 if (wg_debug & WG_DEBUG_FLAGS_TRACE) \ 218 log(LOG_DEBUG, "%s:%d: %s\n", __func__, __LINE__, (msg)); \ 219 } while (0) 220 #else 221 #define WG_TRACE(msg) __nothing 222 #endif 223 224 #ifdef WG_DEBUG_LOG 225 #define WG_DLOG(fmt, args...) do { \ 226 if (wg_debug & WG_DEBUG_FLAGS_LOG) \ 227 log(LOG_DEBUG, "%s: " fmt, __func__, ##args); \ 228 } while (0) 229 #else 230 #define WG_DLOG(fmt, args...) __nothing 231 #endif 232 233 #define WG_LOG_RATECHECK(wgprc, level, fmt, args...) do { \ 234 if (ppsratecheck(&(wgprc)->wgprc_lasttime, \ 235 &(wgprc)->wgprc_curpps, 1)) { \ 236 log(level, fmt, ##args); \ 237 } \ 238 } while (0) 239 240 #ifdef WG_DEBUG_PARAMS 241 static bool wg_force_underload = false; 242 #endif 243 244 #ifdef WG_DEBUG_DUMP 245 246 static char enomem[10] = "[enomem]"; 247 248 static char * 249 gethexdump(const void *vp, size_t n) 250 { 251 char *buf; 252 const uint8_t *p = vp; 253 size_t i; 254 255 if (n > (SIZE_MAX - 1) / 3) 256 return enomem; 257 buf = kmem_alloc(3 * n + 1, KM_NOSLEEP); 258 if (buf == NULL) 259 return enomem; 260 for (i = 0; i < n; i++) 261 snprintf(buf + 3 * i, 3 + 1, " %02hhx", p[i]); 262 return buf; 263 } 264 265 static void 266 puthexdump(char *buf, const void *p, size_t n) 267 { 268 269 if (buf == NULL || buf == enomem) 270 return; 271 kmem_free(buf, 3*n + 1); 272 } 273 274 #ifdef WG_RUMPKERNEL 275 static void 276 wg_dump_buf(const char *func, const char *buf, const size_t size) 277 { 278 if ((wg_debug & WG_DEBUG_FLAGS_DUMP) == 0) 279 return; 280 281 char *hex = gethexdump(buf, size); 282 283 log(LOG_DEBUG, "%s: %s\n", func, hex); 284 puthexdump(hex, buf, size); 285 } 286 #endif 287 288 static void 289 wg_dump_hash(const uint8_t *func, const uint8_t *name, const uint8_t *hash, 290 const size_t size) 291 { 292 if ((wg_debug & WG_DEBUG_FLAGS_DUMP) == 0) 293 return; 294 295 char *hex = gethexdump(hash, size); 296 297 log(LOG_DEBUG, "%s: %s: %s\n", func, name, hex); 298 puthexdump(hex, hash, size); 299 } 300 301 #define WG_DUMP_HASH(name, hash) \ 302 wg_dump_hash(__func__, name, hash, WG_HASH_LEN) 303 #define WG_DUMP_HASH48(name, hash) \ 304 wg_dump_hash(__func__, name, hash, 48) 305 #define WG_DUMP_BUF(buf, size) \ 306 wg_dump_buf(__func__, buf, size) 307 #else 308 #define WG_DUMP_HASH(name, hash) __nothing 309 #define WG_DUMP_HASH48(name, hash) __nothing 310 #define WG_DUMP_BUF(buf, size) __nothing 311 #endif /* WG_DEBUG_DUMP */ 312 313 /* chosen somewhat arbitrarily -- fits in signed 16 bits NUL-terminated */ 314 #define WG_MAX_PROPLEN 32766 315 316 #define WG_MTU 1420 317 #define WG_ALLOWEDIPS 16 318 319 #define CURVE25519_KEY_LEN 32 320 #define TAI64N_LEN sizeof(uint32_t) * 3 321 #define POLY1305_AUTHTAG_LEN 16 322 #define HMAC_BLOCK_LEN 64 323 324 /* [N] 4.1: "DHLEN must be 32 or greater." WireGuard chooses 32. */ 325 /* [N] 4.3: Hash functions */ 326 #define NOISE_DHLEN 32 327 /* [N] 4.3: "Must be 32 or 64." WireGuard chooses 32. */ 328 #define NOISE_HASHLEN 32 329 #define NOISE_BLOCKLEN 64 330 #define NOISE_HKDF_OUTPUT_LEN NOISE_HASHLEN 331 /* [N] 5.1: "k" */ 332 #define NOISE_CIPHER_KEY_LEN 32 333 /* 334 * [N] 9.2: "psk" 335 * "... psk is a 32-byte secret value provided by the application." 336 */ 337 #define NOISE_PRESHARED_KEY_LEN 32 338 339 #define WG_STATIC_KEY_LEN CURVE25519_KEY_LEN 340 #define WG_TIMESTAMP_LEN TAI64N_LEN 341 342 #define WG_PRESHARED_KEY_LEN NOISE_PRESHARED_KEY_LEN 343 344 #define WG_COOKIE_LEN 16 345 #define WG_MAC_LEN 16 346 #define WG_RANDVAL_LEN 24 347 348 #define WG_EPHEMERAL_KEY_LEN CURVE25519_KEY_LEN 349 /* [N] 5.2: "ck: A chaining key of HASHLEN bytes" */ 350 #define WG_CHAINING_KEY_LEN NOISE_HASHLEN 351 /* [N] 5.2: "h: A hash output of HASHLEN bytes" */ 352 #define WG_HASH_LEN NOISE_HASHLEN 353 #define WG_CIPHER_KEY_LEN NOISE_CIPHER_KEY_LEN 354 #define WG_DH_OUTPUT_LEN NOISE_DHLEN 355 #define WG_KDF_OUTPUT_LEN NOISE_HKDF_OUTPUT_LEN 356 #define WG_AUTHTAG_LEN POLY1305_AUTHTAG_LEN 357 #define WG_DATA_KEY_LEN 32 358 #define WG_SALT_LEN 24 359 360 /* 361 * The protocol messages 362 */ 363 struct wg_msg { 364 uint32_t wgm_type; 365 } __packed; 366 367 /* [W] 5.4.2 First Message: Initiator to Responder */ 368 struct wg_msg_init { 369 uint32_t wgmi_type; 370 uint32_t wgmi_sender; 371 uint8_t wgmi_ephemeral[WG_EPHEMERAL_KEY_LEN]; 372 uint8_t wgmi_static[WG_STATIC_KEY_LEN + WG_AUTHTAG_LEN]; 373 uint8_t wgmi_timestamp[WG_TIMESTAMP_LEN + WG_AUTHTAG_LEN]; 374 uint8_t wgmi_mac1[WG_MAC_LEN]; 375 uint8_t wgmi_mac2[WG_MAC_LEN]; 376 } __packed; 377 378 /* [W] 5.4.3 Second Message: Responder to Initiator */ 379 struct wg_msg_resp { 380 uint32_t wgmr_type; 381 uint32_t wgmr_sender; 382 uint32_t wgmr_receiver; 383 uint8_t wgmr_ephemeral[WG_EPHEMERAL_KEY_LEN]; 384 uint8_t wgmr_empty[0 + WG_AUTHTAG_LEN]; 385 uint8_t wgmr_mac1[WG_MAC_LEN]; 386 uint8_t wgmr_mac2[WG_MAC_LEN]; 387 } __packed; 388 389 /* [W] 5.4.6 Subsequent Messages: Transport Data Messages */ 390 struct wg_msg_data { 391 uint32_t wgmd_type; 392 uint32_t wgmd_receiver; 393 uint64_t wgmd_counter; 394 uint32_t wgmd_packet[0]; 395 } __packed; 396 397 /* [W] 5.4.7 Under Load: Cookie Reply Message */ 398 struct wg_msg_cookie { 399 uint32_t wgmc_type; 400 uint32_t wgmc_receiver; 401 uint8_t wgmc_salt[WG_SALT_LEN]; 402 uint8_t wgmc_cookie[WG_COOKIE_LEN + WG_AUTHTAG_LEN]; 403 } __packed; 404 405 #define WG_MSG_TYPE_INIT 1 406 #define WG_MSG_TYPE_RESP 2 407 #define WG_MSG_TYPE_COOKIE 3 408 #define WG_MSG_TYPE_DATA 4 409 #define WG_MSG_TYPE_MAX WG_MSG_TYPE_DATA 410 411 /* Sliding windows */ 412 413 #define SLIWIN_BITS 2048u 414 #define SLIWIN_TYPE uint32_t 415 #define SLIWIN_BPW NBBY*sizeof(SLIWIN_TYPE) 416 #define SLIWIN_WORDS howmany(SLIWIN_BITS, SLIWIN_BPW) 417 #define SLIWIN_NPKT (SLIWIN_BITS - NBBY*sizeof(SLIWIN_TYPE)) 418 419 struct sliwin { 420 SLIWIN_TYPE B[SLIWIN_WORDS]; 421 uint64_t T; 422 }; 423 424 static void 425 sliwin_reset(struct sliwin *W) 426 { 427 428 memset(W, 0, sizeof(*W)); 429 } 430 431 static int 432 sliwin_check_fast(const volatile struct sliwin *W, uint64_t S) 433 { 434 435 /* 436 * If it's more than one window older than the highest sequence 437 * number we've seen, reject. 438 */ 439 #ifdef __HAVE_ATOMIC64_LOADSTORE 440 if (S + SLIWIN_NPKT < atomic_load_relaxed(&W->T)) 441 return EAUTH; 442 #endif 443 444 /* 445 * Otherwise, we need to take the lock to decide, so don't 446 * reject just yet. Caller must serialize a call to 447 * sliwin_update in this case. 448 */ 449 return 0; 450 } 451 452 static int 453 sliwin_update(struct sliwin *W, uint64_t S) 454 { 455 unsigned word, bit; 456 457 /* 458 * If it's more than one window older than the highest sequence 459 * number we've seen, reject. 460 */ 461 if (S + SLIWIN_NPKT < W->T) 462 return EAUTH; 463 464 /* 465 * If it's higher than the highest sequence number we've seen, 466 * advance the window. 467 */ 468 if (S > W->T) { 469 uint64_t i = W->T / SLIWIN_BPW; 470 uint64_t j = S / SLIWIN_BPW; 471 unsigned k; 472 473 for (k = 0; k < MIN(j - i, SLIWIN_WORDS); k++) 474 W->B[(i + k + 1) % SLIWIN_WORDS] = 0; 475 #ifdef __HAVE_ATOMIC64_LOADSTORE 476 atomic_store_relaxed(&W->T, S); 477 #else 478 W->T = S; 479 #endif 480 } 481 482 /* Test and set the bit -- if already set, reject. */ 483 word = (S / SLIWIN_BPW) % SLIWIN_WORDS; 484 bit = S % SLIWIN_BPW; 485 if (W->B[word] & (1UL << bit)) 486 return EAUTH; 487 W->B[word] |= 1U << bit; 488 489 /* Accept! */ 490 return 0; 491 } 492 493 struct wg_session { 494 struct wg_peer *wgs_peer; 495 struct psref_target 496 wgs_psref; 497 498 int wgs_state; 499 #define WGS_STATE_UNKNOWN 0 500 #define WGS_STATE_INIT_ACTIVE 1 501 #define WGS_STATE_INIT_PASSIVE 2 502 #define WGS_STATE_ESTABLISHED 3 503 #define WGS_STATE_DESTROYING 4 504 505 time_t wgs_time_established; 506 time_t wgs_time_last_data_sent; 507 bool wgs_is_initiator; 508 509 uint32_t wgs_local_index; 510 uint32_t wgs_remote_index; 511 #ifdef __HAVE_ATOMIC64_LOADSTORE 512 volatile uint64_t 513 wgs_send_counter; 514 #else 515 kmutex_t wgs_send_counter_lock; 516 uint64_t wgs_send_counter; 517 #endif 518 519 struct { 520 kmutex_t lock; 521 struct sliwin window; 522 } *wgs_recvwin; 523 524 uint8_t wgs_handshake_hash[WG_HASH_LEN]; 525 uint8_t wgs_chaining_key[WG_CHAINING_KEY_LEN]; 526 uint8_t wgs_ephemeral_key_pub[WG_EPHEMERAL_KEY_LEN]; 527 uint8_t wgs_ephemeral_key_priv[WG_EPHEMERAL_KEY_LEN]; 528 uint8_t wgs_ephemeral_key_peer[WG_EPHEMERAL_KEY_LEN]; 529 uint8_t wgs_tkey_send[WG_DATA_KEY_LEN]; 530 uint8_t wgs_tkey_recv[WG_DATA_KEY_LEN]; 531 }; 532 533 struct wg_sockaddr { 534 union { 535 struct sockaddr_storage _ss; 536 struct sockaddr _sa; 537 struct sockaddr_in _sin; 538 struct sockaddr_in6 _sin6; 539 }; 540 struct psref_target wgsa_psref; 541 }; 542 543 #define wgsatoss(wgsa) (&(wgsa)->_ss) 544 #define wgsatosa(wgsa) (&(wgsa)->_sa) 545 #define wgsatosin(wgsa) (&(wgsa)->_sin) 546 #define wgsatosin6(wgsa) (&(wgsa)->_sin6) 547 548 #define wgsa_family(wgsa) (wgsatosa(wgsa)->sa_family) 549 550 struct wg_peer; 551 struct wg_allowedip { 552 struct radix_node wga_nodes[2]; 553 struct wg_sockaddr _wga_sa_addr; 554 struct wg_sockaddr _wga_sa_mask; 555 #define wga_sa_addr _wga_sa_addr._sa 556 #define wga_sa_mask _wga_sa_mask._sa 557 558 int wga_family; 559 uint8_t wga_cidr; 560 union { 561 struct in_addr _ip4; 562 struct in6_addr _ip6; 563 } wga_addr; 564 #define wga_addr4 wga_addr._ip4 565 #define wga_addr6 wga_addr._ip6 566 567 struct wg_peer *wga_peer; 568 }; 569 570 typedef uint8_t wg_timestamp_t[WG_TIMESTAMP_LEN]; 571 572 struct wg_ppsratecheck { 573 struct timeval wgprc_lasttime; 574 int wgprc_curpps; 575 }; 576 577 struct wg_softc; 578 struct wg_peer { 579 struct wg_softc *wgp_sc; 580 char wgp_name[WG_PEER_NAME_MAXLEN + 1]; 581 struct pslist_entry wgp_peerlist_entry; 582 pserialize_t wgp_psz; 583 struct psref_target wgp_psref; 584 kmutex_t *wgp_lock; 585 kmutex_t *wgp_intr_lock; 586 587 uint8_t wgp_pubkey[WG_STATIC_KEY_LEN]; 588 struct wg_sockaddr *wgp_endpoint; 589 struct wg_sockaddr *wgp_endpoint0; 590 volatile unsigned wgp_endpoint_changing; 591 bool wgp_endpoint_available; 592 593 /* The preshared key (optional) */ 594 uint8_t wgp_psk[WG_PRESHARED_KEY_LEN]; 595 596 struct wg_session *wgp_session_stable; 597 struct wg_session *wgp_session_unstable; 598 599 /* first outgoing packet awaiting session initiation */ 600 struct mbuf *wgp_pending; 601 602 /* timestamp in big-endian */ 603 wg_timestamp_t wgp_timestamp_latest_init; 604 605 struct timespec wgp_last_handshake_time; 606 607 callout_t wgp_rekey_timer; 608 callout_t wgp_handshake_timeout_timer; 609 callout_t wgp_session_dtor_timer; 610 611 time_t wgp_handshake_start_time; 612 613 int wgp_n_allowedips; 614 struct wg_allowedip wgp_allowedips[WG_ALLOWEDIPS]; 615 616 time_t wgp_latest_cookie_time; 617 uint8_t wgp_latest_cookie[WG_COOKIE_LEN]; 618 uint8_t wgp_last_sent_mac1[WG_MAC_LEN]; 619 bool wgp_last_sent_mac1_valid; 620 uint8_t wgp_last_sent_cookie[WG_COOKIE_LEN]; 621 bool wgp_last_sent_cookie_valid; 622 623 time_t wgp_last_msg_received_time[WG_MSG_TYPE_MAX]; 624 625 time_t wgp_last_genrandval_time; 626 uint32_t wgp_randval; 627 628 struct wg_ppsratecheck wgp_ppsratecheck; 629 630 struct work wgp_work; 631 unsigned int wgp_tasks; 632 #define WGP_TASK_SEND_INIT_MESSAGE __BIT(0) 633 #define WGP_TASK_RETRY_HANDSHAKE __BIT(1) 634 #define WGP_TASK_ESTABLISH_SESSION __BIT(2) 635 #define WGP_TASK_ENDPOINT_CHANGED __BIT(3) 636 #define WGP_TASK_SEND_KEEPALIVE_MESSAGE __BIT(4) 637 #define WGP_TASK_DESTROY_PREV_SESSION __BIT(5) 638 }; 639 640 struct wg_ops; 641 642 struct wg_softc { 643 struct ifnet wg_if; 644 LIST_ENTRY(wg_softc) wg_list; 645 kmutex_t *wg_lock; 646 kmutex_t *wg_intr_lock; 647 krwlock_t *wg_rwlock; 648 649 uint8_t wg_privkey[WG_STATIC_KEY_LEN]; 650 uint8_t wg_pubkey[WG_STATIC_KEY_LEN]; 651 652 int wg_npeers; 653 struct pslist_head wg_peers; 654 struct thmap *wg_peers_bypubkey; 655 struct thmap *wg_peers_byname; 656 struct thmap *wg_sessions_byindex; 657 uint16_t wg_listen_port; 658 659 struct threadpool *wg_threadpool; 660 661 struct threadpool_job wg_job; 662 int wg_upcalls; 663 #define WG_UPCALL_INET __BIT(0) 664 #define WG_UPCALL_INET6 __BIT(1) 665 666 #ifdef INET 667 struct socket *wg_so4; 668 struct radix_node_head *wg_rtable_ipv4; 669 #endif 670 #ifdef INET6 671 struct socket *wg_so6; 672 struct radix_node_head *wg_rtable_ipv6; 673 #endif 674 675 struct wg_ppsratecheck wg_ppsratecheck; 676 677 struct wg_ops *wg_ops; 678 679 #ifdef WG_RUMPKERNEL 680 struct wg_user *wg_user; 681 #endif 682 }; 683 684 /* [W] 6.1 Preliminaries */ 685 #define WG_REKEY_AFTER_MESSAGES (1ULL << 60) 686 #define WG_REJECT_AFTER_MESSAGES (UINT64_MAX - (1 << 13)) 687 #define WG_REKEY_AFTER_TIME 120 688 #define WG_REJECT_AFTER_TIME 180 689 #define WG_REKEY_ATTEMPT_TIME 90 690 #define WG_REKEY_TIMEOUT 5 691 #define WG_KEEPALIVE_TIMEOUT 10 692 693 #define WG_COOKIE_TIME 120 694 #define WG_RANDVAL_TIME (2 * 60) 695 696 static uint64_t wg_rekey_after_messages = WG_REKEY_AFTER_MESSAGES; 697 static uint64_t wg_reject_after_messages = WG_REJECT_AFTER_MESSAGES; 698 static unsigned wg_rekey_after_time = WG_REKEY_AFTER_TIME; 699 static unsigned wg_reject_after_time = WG_REJECT_AFTER_TIME; 700 static unsigned wg_rekey_attempt_time = WG_REKEY_ATTEMPT_TIME; 701 static unsigned wg_rekey_timeout = WG_REKEY_TIMEOUT; 702 static unsigned wg_keepalive_timeout = WG_KEEPALIVE_TIMEOUT; 703 704 static struct mbuf * 705 wg_get_mbuf(size_t, size_t); 706 707 static int wg_send_data_msg(struct wg_peer *, struct wg_session *, 708 struct mbuf *); 709 static int wg_send_cookie_msg(struct wg_softc *, struct wg_peer *, 710 const uint32_t, const uint8_t [WG_MAC_LEN], 711 const struct sockaddr *); 712 static int wg_send_handshake_msg_resp(struct wg_softc *, struct wg_peer *, 713 struct wg_session *, const struct wg_msg_init *); 714 static void wg_send_keepalive_msg(struct wg_peer *, struct wg_session *); 715 716 static struct wg_peer * 717 wg_pick_peer_by_sa(struct wg_softc *, const struct sockaddr *, 718 struct psref *); 719 static struct wg_peer * 720 wg_lookup_peer_by_pubkey(struct wg_softc *, 721 const uint8_t [WG_STATIC_KEY_LEN], struct psref *); 722 723 static struct wg_session * 724 wg_lookup_session_by_index(struct wg_softc *, 725 const uint32_t, struct psref *); 726 727 static void wg_update_endpoint_if_necessary(struct wg_peer *, 728 const struct sockaddr *); 729 730 static void wg_schedule_rekey_timer(struct wg_peer *); 731 static void wg_schedule_session_dtor_timer(struct wg_peer *); 732 733 static bool wg_is_underload(struct wg_softc *, struct wg_peer *, int); 734 static void wg_calculate_keys(struct wg_session *, const bool); 735 736 static void wg_clear_states(struct wg_session *); 737 738 static void wg_get_peer(struct wg_peer *, struct psref *); 739 static void wg_put_peer(struct wg_peer *, struct psref *); 740 741 static int wg_send_so(struct wg_peer *, struct mbuf *); 742 static int wg_send_udp(struct wg_peer *, struct mbuf *); 743 static int wg_output(struct ifnet *, struct mbuf *, 744 const struct sockaddr *, const struct rtentry *); 745 static void wg_input(struct ifnet *, struct mbuf *, const int); 746 static int wg_ioctl(struct ifnet *, u_long, void *); 747 static int wg_bind_port(struct wg_softc *, const uint16_t); 748 static int wg_init(struct ifnet *); 749 #ifdef ALTQ 750 static void wg_start(struct ifnet *); 751 #endif 752 static void wg_stop(struct ifnet *, int); 753 754 static void wg_peer_work(struct work *, void *); 755 static void wg_job(struct threadpool_job *); 756 static void wgintr(void *); 757 static void wg_purge_pending_packets(struct wg_peer *); 758 759 static int wg_clone_create(struct if_clone *, int); 760 static int wg_clone_destroy(struct ifnet *); 761 762 struct wg_ops { 763 int (*send_hs_msg)(struct wg_peer *, struct mbuf *); 764 int (*send_data_msg)(struct wg_peer *, struct mbuf *); 765 void (*input)(struct ifnet *, struct mbuf *, const int); 766 int (*bind_port)(struct wg_softc *, const uint16_t); 767 }; 768 769 struct wg_ops wg_ops_rumpkernel = { 770 .send_hs_msg = wg_send_so, 771 .send_data_msg = wg_send_udp, 772 .input = wg_input, 773 .bind_port = wg_bind_port, 774 }; 775 776 #ifdef WG_RUMPKERNEL 777 static bool wg_user_mode(struct wg_softc *); 778 static int wg_ioctl_linkstr(struct wg_softc *, struct ifdrv *); 779 780 static int wg_send_user(struct wg_peer *, struct mbuf *); 781 static void wg_input_user(struct ifnet *, struct mbuf *, const int); 782 static int wg_bind_port_user(struct wg_softc *, const uint16_t); 783 784 struct wg_ops wg_ops_rumpuser = { 785 .send_hs_msg = wg_send_user, 786 .send_data_msg = wg_send_user, 787 .input = wg_input_user, 788 .bind_port = wg_bind_port_user, 789 }; 790 #endif 791 792 #define WG_PEER_READER_FOREACH(wgp, wg) \ 793 PSLIST_READER_FOREACH((wgp), &(wg)->wg_peers, struct wg_peer, \ 794 wgp_peerlist_entry) 795 #define WG_PEER_WRITER_FOREACH(wgp, wg) \ 796 PSLIST_WRITER_FOREACH((wgp), &(wg)->wg_peers, struct wg_peer, \ 797 wgp_peerlist_entry) 798 #define WG_PEER_WRITER_INSERT_HEAD(wgp, wg) \ 799 PSLIST_WRITER_INSERT_HEAD(&(wg)->wg_peers, (wgp), wgp_peerlist_entry) 800 #define WG_PEER_WRITER_REMOVE(wgp) \ 801 PSLIST_WRITER_REMOVE((wgp), wgp_peerlist_entry) 802 803 struct wg_route { 804 struct radix_node wgr_nodes[2]; 805 struct wg_peer *wgr_peer; 806 }; 807 808 static struct radix_node_head * 809 wg_rnh(struct wg_softc *wg, const int family) 810 { 811 812 switch (family) { 813 case AF_INET: 814 return wg->wg_rtable_ipv4; 815 #ifdef INET6 816 case AF_INET6: 817 return wg->wg_rtable_ipv6; 818 #endif 819 default: 820 return NULL; 821 } 822 } 823 824 825 /* 826 * Global variables 827 */ 828 static volatile unsigned wg_count __cacheline_aligned; 829 830 struct psref_class *wg_psref_class __read_mostly; 831 832 static struct if_clone wg_cloner = 833 IF_CLONE_INITIALIZER("wg", wg_clone_create, wg_clone_destroy); 834 835 static struct pktqueue *wg_pktq __read_mostly; 836 static struct workqueue *wg_wq __read_mostly; 837 838 void wgattach(int); 839 /* ARGSUSED */ 840 void 841 wgattach(int count) 842 { 843 /* 844 * Nothing to do here, initialization is handled by the 845 * module initialization code in wginit() below). 846 */ 847 } 848 849 static void 850 wginit(void) 851 { 852 853 wg_psref_class = psref_class_create("wg", IPL_SOFTNET); 854 855 if_clone_attach(&wg_cloner); 856 } 857 858 /* 859 * XXX Kludge: This should just happen in wginit, but workqueue_create 860 * cannot be run until after CPUs have been detected, and wginit runs 861 * before configure. 862 */ 863 static int 864 wginitqueues(void) 865 { 866 int error __diagused; 867 868 wg_pktq = pktq_create(IFQ_MAXLEN, wgintr, NULL); 869 KASSERT(wg_pktq != NULL); 870 871 error = workqueue_create(&wg_wq, "wgpeer", wg_peer_work, NULL, 872 PRI_NONE, IPL_SOFTNET, WQ_MPSAFE|WQ_PERCPU); 873 KASSERT(error == 0); 874 875 return 0; 876 } 877 878 static void 879 wg_guarantee_initialized(void) 880 { 881 static ONCE_DECL(init); 882 int error __diagused; 883 884 error = RUN_ONCE(&init, wginitqueues); 885 KASSERT(error == 0); 886 } 887 888 static int 889 wg_count_inc(void) 890 { 891 unsigned o, n; 892 893 do { 894 o = atomic_load_relaxed(&wg_count); 895 if (o == UINT_MAX) 896 return ENFILE; 897 n = o + 1; 898 } while (atomic_cas_uint(&wg_count, o, n) != o); 899 900 return 0; 901 } 902 903 static void 904 wg_count_dec(void) 905 { 906 unsigned c __diagused; 907 908 c = atomic_dec_uint_nv(&wg_count); 909 KASSERT(c != UINT_MAX); 910 } 911 912 static int 913 wgdetach(void) 914 { 915 916 /* Prevent new interface creation. */ 917 if_clone_detach(&wg_cloner); 918 919 /* Check whether there are any existing interfaces. */ 920 if (atomic_load_relaxed(&wg_count)) { 921 /* Back out -- reattach the cloner. */ 922 if_clone_attach(&wg_cloner); 923 return EBUSY; 924 } 925 926 /* No interfaces left. Nuke it. */ 927 workqueue_destroy(wg_wq); 928 pktq_destroy(wg_pktq); 929 psref_class_destroy(wg_psref_class); 930 931 return 0; 932 } 933 934 static void 935 wg_init_key_and_hash(uint8_t ckey[WG_CHAINING_KEY_LEN], 936 uint8_t hash[WG_HASH_LEN]) 937 { 938 /* [W] 5.4: CONSTRUCTION */ 939 const char *signature = "Noise_IKpsk2_25519_ChaChaPoly_BLAKE2s"; 940 /* [W] 5.4: IDENTIFIER */ 941 const char *id = "WireGuard v1 zx2c4 Jason (at) zx2c4.com"; 942 struct blake2s state; 943 944 blake2s(ckey, WG_CHAINING_KEY_LEN, NULL, 0, 945 signature, strlen(signature)); 946 947 CTASSERT(WG_HASH_LEN == WG_CHAINING_KEY_LEN); 948 memcpy(hash, ckey, WG_CHAINING_KEY_LEN); 949 950 blake2s_init(&state, WG_HASH_LEN, NULL, 0); 951 blake2s_update(&state, ckey, WG_CHAINING_KEY_LEN); 952 blake2s_update(&state, id, strlen(id)); 953 blake2s_final(&state, hash); 954 955 WG_DUMP_HASH("ckey", ckey); 956 WG_DUMP_HASH("hash", hash); 957 } 958 959 static void 960 wg_algo_hash(uint8_t hash[WG_HASH_LEN], const uint8_t input[], 961 const size_t inputsize) 962 { 963 struct blake2s state; 964 965 blake2s_init(&state, WG_HASH_LEN, NULL, 0); 966 blake2s_update(&state, hash, WG_HASH_LEN); 967 blake2s_update(&state, input, inputsize); 968 blake2s_final(&state, hash); 969 } 970 971 static void 972 wg_algo_mac(uint8_t out[], const size_t outsize, 973 const uint8_t key[], const size_t keylen, 974 const uint8_t input1[], const size_t input1len, 975 const uint8_t input2[], const size_t input2len) 976 { 977 struct blake2s state; 978 979 blake2s_init(&state, outsize, key, keylen); 980 981 blake2s_update(&state, input1, input1len); 982 if (input2 != NULL) 983 blake2s_update(&state, input2, input2len); 984 blake2s_final(&state, out); 985 } 986 987 static void 988 wg_algo_mac_mac1(uint8_t out[], const size_t outsize, 989 const uint8_t input1[], const size_t input1len, 990 const uint8_t input2[], const size_t input2len) 991 { 992 struct blake2s state; 993 /* [W] 5.4: LABEL-MAC1 */ 994 const char *label = "mac1----"; 995 uint8_t key[WG_HASH_LEN]; 996 997 blake2s_init(&state, sizeof(key), NULL, 0); 998 blake2s_update(&state, label, strlen(label)); 999 blake2s_update(&state, input1, input1len); 1000 blake2s_final(&state, key); 1001 1002 blake2s_init(&state, outsize, key, sizeof(key)); 1003 if (input2 != NULL) 1004 blake2s_update(&state, input2, input2len); 1005 blake2s_final(&state, out); 1006 } 1007 1008 static void 1009 wg_algo_mac_cookie(uint8_t out[], const size_t outsize, 1010 const uint8_t input1[], const size_t input1len) 1011 { 1012 struct blake2s state; 1013 /* [W] 5.4: LABEL-COOKIE */ 1014 const char *label = "cookie--"; 1015 1016 blake2s_init(&state, outsize, NULL, 0); 1017 blake2s_update(&state, label, strlen(label)); 1018 blake2s_update(&state, input1, input1len); 1019 blake2s_final(&state, out); 1020 } 1021 1022 static void 1023 wg_algo_generate_keypair(uint8_t pubkey[WG_EPHEMERAL_KEY_LEN], 1024 uint8_t privkey[WG_EPHEMERAL_KEY_LEN]) 1025 { 1026 1027 CTASSERT(WG_EPHEMERAL_KEY_LEN == crypto_scalarmult_curve25519_BYTES); 1028 1029 cprng_strong(kern_cprng, privkey, WG_EPHEMERAL_KEY_LEN, 0); 1030 crypto_scalarmult_base(pubkey, privkey); 1031 } 1032 1033 static void 1034 wg_algo_dh(uint8_t out[WG_DH_OUTPUT_LEN], 1035 const uint8_t privkey[WG_STATIC_KEY_LEN], 1036 const uint8_t pubkey[WG_STATIC_KEY_LEN]) 1037 { 1038 1039 CTASSERT(WG_STATIC_KEY_LEN == crypto_scalarmult_curve25519_BYTES); 1040 1041 int ret __diagused = crypto_scalarmult(out, privkey, pubkey); 1042 KASSERT(ret == 0); 1043 } 1044 1045 static void 1046 wg_algo_hmac(uint8_t out[], const size_t outlen, 1047 const uint8_t key[], const size_t keylen, 1048 const uint8_t in[], const size_t inlen) 1049 { 1050 #define IPAD 0x36 1051 #define OPAD 0x5c 1052 uint8_t hmackey[HMAC_BLOCK_LEN] = {0}; 1053 uint8_t ipad[HMAC_BLOCK_LEN]; 1054 uint8_t opad[HMAC_BLOCK_LEN]; 1055 size_t i; 1056 struct blake2s state; 1057 1058 KASSERT(outlen == WG_HASH_LEN); 1059 KASSERT(keylen <= HMAC_BLOCK_LEN); 1060 1061 memcpy(hmackey, key, keylen); 1062 1063 for (i = 0; i < sizeof(hmackey); i++) { 1064 ipad[i] = hmackey[i] ^ IPAD; 1065 opad[i] = hmackey[i] ^ OPAD; 1066 } 1067 1068 blake2s_init(&state, WG_HASH_LEN, NULL, 0); 1069 blake2s_update(&state, ipad, sizeof(ipad)); 1070 blake2s_update(&state, in, inlen); 1071 blake2s_final(&state, out); 1072 1073 blake2s_init(&state, WG_HASH_LEN, NULL, 0); 1074 blake2s_update(&state, opad, sizeof(opad)); 1075 blake2s_update(&state, out, WG_HASH_LEN); 1076 blake2s_final(&state, out); 1077 #undef IPAD 1078 #undef OPAD 1079 } 1080 1081 static void 1082 wg_algo_kdf(uint8_t out1[WG_KDF_OUTPUT_LEN], uint8_t out2[WG_KDF_OUTPUT_LEN], 1083 uint8_t out3[WG_KDF_OUTPUT_LEN], const uint8_t ckey[WG_CHAINING_KEY_LEN], 1084 const uint8_t input[], const size_t inputlen) 1085 { 1086 uint8_t tmp1[WG_KDF_OUTPUT_LEN], tmp2[WG_KDF_OUTPUT_LEN + 1]; 1087 uint8_t one[1]; 1088 1089 /* 1090 * [N] 4.3: "an input_key_material byte sequence with length 1091 * either zero bytes, 32 bytes, or DHLEN bytes." 1092 */ 1093 KASSERT(inputlen == 0 || inputlen == 32 || inputlen == NOISE_DHLEN); 1094 1095 WG_DUMP_HASH("ckey", ckey); 1096 if (input != NULL) 1097 WG_DUMP_HASH("input", input); 1098 wg_algo_hmac(tmp1, sizeof(tmp1), ckey, WG_CHAINING_KEY_LEN, 1099 input, inputlen); 1100 WG_DUMP_HASH("tmp1", tmp1); 1101 one[0] = 1; 1102 wg_algo_hmac(out1, WG_KDF_OUTPUT_LEN, tmp1, sizeof(tmp1), 1103 one, sizeof(one)); 1104 WG_DUMP_HASH("out1", out1); 1105 if (out2 == NULL) 1106 return; 1107 memcpy(tmp2, out1, WG_KDF_OUTPUT_LEN); 1108 tmp2[WG_KDF_OUTPUT_LEN] = 2; 1109 wg_algo_hmac(out2, WG_KDF_OUTPUT_LEN, tmp1, sizeof(tmp1), 1110 tmp2, sizeof(tmp2)); 1111 WG_DUMP_HASH("out2", out2); 1112 if (out3 == NULL) 1113 return; 1114 memcpy(tmp2, out2, WG_KDF_OUTPUT_LEN); 1115 tmp2[WG_KDF_OUTPUT_LEN] = 3; 1116 wg_algo_hmac(out3, WG_KDF_OUTPUT_LEN, tmp1, sizeof(tmp1), 1117 tmp2, sizeof(tmp2)); 1118 WG_DUMP_HASH("out3", out3); 1119 } 1120 1121 static void __noinline 1122 wg_algo_dh_kdf(uint8_t ckey[WG_CHAINING_KEY_LEN], 1123 uint8_t cipher_key[WG_CIPHER_KEY_LEN], 1124 const uint8_t local_key[WG_STATIC_KEY_LEN], 1125 const uint8_t remote_key[WG_STATIC_KEY_LEN]) 1126 { 1127 uint8_t dhout[WG_DH_OUTPUT_LEN]; 1128 1129 wg_algo_dh(dhout, local_key, remote_key); 1130 wg_algo_kdf(ckey, cipher_key, NULL, ckey, dhout, sizeof(dhout)); 1131 1132 WG_DUMP_HASH("dhout", dhout); 1133 WG_DUMP_HASH("ckey", ckey); 1134 if (cipher_key != NULL) 1135 WG_DUMP_HASH("cipher_key", cipher_key); 1136 } 1137 1138 static void 1139 wg_algo_aead_enc(uint8_t out[], size_t expected_outsize, const uint8_t key[], 1140 const uint64_t counter, const uint8_t plain[], const size_t plainsize, 1141 const uint8_t auth[], size_t authlen) 1142 { 1143 uint8_t nonce[(32 + 64) / 8] = {0}; 1144 long long unsigned int outsize; 1145 int error __diagused; 1146 1147 le64enc(&nonce[4], counter); 1148 1149 error = crypto_aead_chacha20poly1305_ietf_encrypt(out, &outsize, plain, 1150 plainsize, auth, authlen, NULL, nonce, key); 1151 KASSERT(error == 0); 1152 KASSERT(outsize == expected_outsize); 1153 } 1154 1155 static int 1156 wg_algo_aead_dec(uint8_t out[], size_t expected_outsize, const uint8_t key[], 1157 const uint64_t counter, const uint8_t encrypted[], 1158 const size_t encryptedsize, const uint8_t auth[], size_t authlen) 1159 { 1160 uint8_t nonce[(32 + 64) / 8] = {0}; 1161 long long unsigned int outsize; 1162 int error; 1163 1164 le64enc(&nonce[4], counter); 1165 1166 error = crypto_aead_chacha20poly1305_ietf_decrypt(out, &outsize, NULL, 1167 encrypted, encryptedsize, auth, authlen, nonce, key); 1168 if (error == 0) 1169 KASSERT(outsize == expected_outsize); 1170 return error; 1171 } 1172 1173 static void 1174 wg_algo_xaead_enc(uint8_t out[], const size_t expected_outsize, 1175 const uint8_t key[], const uint8_t plain[], const size_t plainsize, 1176 const uint8_t auth[], size_t authlen, 1177 const uint8_t nonce[WG_SALT_LEN]) 1178 { 1179 long long unsigned int outsize; 1180 int error __diagused; 1181 1182 CTASSERT(WG_SALT_LEN == crypto_aead_xchacha20poly1305_ietf_NPUBBYTES); 1183 error = crypto_aead_xchacha20poly1305_ietf_encrypt(out, &outsize, 1184 plain, plainsize, auth, authlen, NULL, nonce, key); 1185 KASSERT(error == 0); 1186 KASSERT(outsize == expected_outsize); 1187 } 1188 1189 static int 1190 wg_algo_xaead_dec(uint8_t out[], const size_t expected_outsize, 1191 const uint8_t key[], const uint8_t encrypted[], const size_t encryptedsize, 1192 const uint8_t auth[], size_t authlen, 1193 const uint8_t nonce[WG_SALT_LEN]) 1194 { 1195 long long unsigned int outsize; 1196 int error; 1197 1198 error = crypto_aead_xchacha20poly1305_ietf_decrypt(out, &outsize, NULL, 1199 encrypted, encryptedsize, auth, authlen, nonce, key); 1200 if (error == 0) 1201 KASSERT(outsize == expected_outsize); 1202 return error; 1203 } 1204 1205 static void 1206 wg_algo_tai64n(wg_timestamp_t timestamp) 1207 { 1208 struct timespec ts; 1209 1210 /* FIXME strict TAI64N (https://cr.yp.to/libtai/tai64.html) */ 1211 getnanotime(&ts); 1212 /* TAI64 label in external TAI64 format */ 1213 be32enc(timestamp, 0x40000000U + (uint32_t)(ts.tv_sec >> 32)); 1214 /* second beginning from 1970 TAI */ 1215 be32enc(timestamp + 4, (uint32_t)(ts.tv_sec & 0xffffffffU)); 1216 /* nanosecond in big-endian format */ 1217 be32enc(timestamp + 8, (uint32_t)ts.tv_nsec); 1218 } 1219 1220 /* 1221 * wg_get_stable_session(wgp, psref) 1222 * 1223 * Get a passive reference to the current stable session, or 1224 * return NULL if there is no current stable session. 1225 * 1226 * The pointer is always there but the session is not necessarily 1227 * ESTABLISHED; if it is not ESTABLISHED, return NULL. However, 1228 * the session may transition from ESTABLISHED to DESTROYING while 1229 * holding the passive reference. 1230 */ 1231 static struct wg_session * 1232 wg_get_stable_session(struct wg_peer *wgp, struct psref *psref) 1233 { 1234 int s; 1235 struct wg_session *wgs; 1236 1237 s = pserialize_read_enter(); 1238 wgs = atomic_load_consume(&wgp->wgp_session_stable); 1239 if (__predict_false(wgs->wgs_state != WGS_STATE_ESTABLISHED)) 1240 wgs = NULL; 1241 else 1242 psref_acquire(psref, &wgs->wgs_psref, wg_psref_class); 1243 pserialize_read_exit(s); 1244 1245 return wgs; 1246 } 1247 1248 static void 1249 wg_put_session(struct wg_session *wgs, struct psref *psref) 1250 { 1251 1252 psref_release(psref, &wgs->wgs_psref, wg_psref_class); 1253 } 1254 1255 static void 1256 wg_destroy_session(struct wg_softc *wg, struct wg_session *wgs) 1257 { 1258 struct wg_peer *wgp = wgs->wgs_peer; 1259 struct wg_session *wgs0 __diagused; 1260 void *garbage; 1261 1262 KASSERT(mutex_owned(wgp->wgp_lock)); 1263 KASSERT(wgs->wgs_state != WGS_STATE_UNKNOWN); 1264 1265 /* Remove the session from the table. */ 1266 wgs0 = thmap_del(wg->wg_sessions_byindex, 1267 &wgs->wgs_local_index, sizeof(wgs->wgs_local_index)); 1268 KASSERT(wgs0 == wgs); 1269 garbage = thmap_stage_gc(wg->wg_sessions_byindex); 1270 1271 /* Wait for passive references to drain. */ 1272 pserialize_perform(wgp->wgp_psz); 1273 psref_target_destroy(&wgs->wgs_psref, wg_psref_class); 1274 1275 /* Free memory, zero state, and transition to UNKNOWN. */ 1276 thmap_gc(wg->wg_sessions_byindex, garbage); 1277 wg_clear_states(wgs); 1278 wgs->wgs_state = WGS_STATE_UNKNOWN; 1279 } 1280 1281 /* 1282 * wg_get_session_index(wg, wgs) 1283 * 1284 * Choose a session index for wgs->wgs_local_index, and store it 1285 * in wg's table of sessions by index. 1286 * 1287 * wgs must be the unstable session of its peer, and must be 1288 * transitioning out of the UNKNOWN state. 1289 */ 1290 static void 1291 wg_get_session_index(struct wg_softc *wg, struct wg_session *wgs) 1292 { 1293 struct wg_peer *wgp __diagused = wgs->wgs_peer; 1294 struct wg_session *wgs0; 1295 uint32_t index; 1296 1297 KASSERT(mutex_owned(wgp->wgp_lock)); 1298 KASSERT(wgs == wgp->wgp_session_unstable); 1299 KASSERT(wgs->wgs_state == WGS_STATE_UNKNOWN); 1300 1301 do { 1302 /* Pick a uniform random index. */ 1303 index = cprng_strong32(); 1304 1305 /* Try to take it. */ 1306 wgs->wgs_local_index = index; 1307 wgs0 = thmap_put(wg->wg_sessions_byindex, 1308 &wgs->wgs_local_index, sizeof wgs->wgs_local_index, wgs); 1309 1310 /* If someone else beat us, start over. */ 1311 } while (__predict_false(wgs0 != wgs)); 1312 } 1313 1314 /* 1315 * wg_put_session_index(wg, wgs) 1316 * 1317 * Remove wgs from the table of sessions by index, wait for any 1318 * passive references to drain, and transition the session to the 1319 * UNKNOWN state. 1320 * 1321 * wgs must be the unstable session of its peer, and must not be 1322 * UNKNOWN or ESTABLISHED. 1323 */ 1324 static void 1325 wg_put_session_index(struct wg_softc *wg, struct wg_session *wgs) 1326 { 1327 struct wg_peer *wgp __diagused = wgs->wgs_peer; 1328 1329 KASSERT(mutex_owned(wgp->wgp_lock)); 1330 KASSERT(wgs == wgp->wgp_session_unstable); 1331 KASSERT(wgs->wgs_state != WGS_STATE_UNKNOWN); 1332 KASSERT(wgs->wgs_state != WGS_STATE_ESTABLISHED); 1333 1334 wg_destroy_session(wg, wgs); 1335 psref_target_init(&wgs->wgs_psref, wg_psref_class); 1336 } 1337 1338 /* 1339 * Handshake patterns 1340 * 1341 * [W] 5: "These messages use the "IK" pattern from Noise" 1342 * [N] 7.5. Interactive handshake patterns (fundamental) 1343 * "The first character refers to the initiators static key:" 1344 * "I = Static key for initiator Immediately transmitted to responder, 1345 * despite reduced or absent identity hiding" 1346 * "The second character refers to the responders static key:" 1347 * "K = Static key for responder Known to initiator" 1348 * "IK: 1349 * <- s 1350 * ... 1351 * -> e, es, s, ss 1352 * <- e, ee, se" 1353 * [N] 9.4. Pattern modifiers 1354 * "IKpsk2: 1355 * <- s 1356 * ... 1357 * -> e, es, s, ss 1358 * <- e, ee, se, psk" 1359 */ 1360 static void 1361 wg_fill_msg_init(struct wg_softc *wg, struct wg_peer *wgp, 1362 struct wg_session *wgs, struct wg_msg_init *wgmi) 1363 { 1364 uint8_t ckey[WG_CHAINING_KEY_LEN]; /* [W] 5.4.2: Ci */ 1365 uint8_t hash[WG_HASH_LEN]; /* [W] 5.4.2: Hi */ 1366 uint8_t cipher_key[WG_CIPHER_KEY_LEN]; 1367 uint8_t pubkey[WG_EPHEMERAL_KEY_LEN]; 1368 uint8_t privkey[WG_EPHEMERAL_KEY_LEN]; 1369 1370 KASSERT(mutex_owned(wgp->wgp_lock)); 1371 KASSERT(wgs == wgp->wgp_session_unstable); 1372 KASSERT(wgs->wgs_state == WGS_STATE_INIT_ACTIVE); 1373 1374 wgmi->wgmi_type = htole32(WG_MSG_TYPE_INIT); 1375 wgmi->wgmi_sender = wgs->wgs_local_index; 1376 1377 /* [W] 5.4.2: First Message: Initiator to Responder */ 1378 1379 /* Ci := HASH(CONSTRUCTION) */ 1380 /* Hi := HASH(Ci || IDENTIFIER) */ 1381 wg_init_key_and_hash(ckey, hash); 1382 /* Hi := HASH(Hi || Sr^pub) */ 1383 wg_algo_hash(hash, wgp->wgp_pubkey, sizeof(wgp->wgp_pubkey)); 1384 1385 WG_DUMP_HASH("hash", hash); 1386 1387 /* [N] 2.2: "e" */ 1388 /* Ei^priv, Ei^pub := DH-GENERATE() */ 1389 wg_algo_generate_keypair(pubkey, privkey); 1390 /* Ci := KDF1(Ci, Ei^pub) */ 1391 wg_algo_kdf(ckey, NULL, NULL, ckey, pubkey, sizeof(pubkey)); 1392 /* msg.ephemeral := Ei^pub */ 1393 memcpy(wgmi->wgmi_ephemeral, pubkey, sizeof(wgmi->wgmi_ephemeral)); 1394 /* Hi := HASH(Hi || msg.ephemeral) */ 1395 wg_algo_hash(hash, pubkey, sizeof(pubkey)); 1396 1397 WG_DUMP_HASH("ckey", ckey); 1398 WG_DUMP_HASH("hash", hash); 1399 1400 /* [N] 2.2: "es" */ 1401 /* Ci, k := KDF2(Ci, DH(Ei^priv, Sr^pub)) */ 1402 wg_algo_dh_kdf(ckey, cipher_key, privkey, wgp->wgp_pubkey); 1403 1404 /* [N] 2.2: "s" */ 1405 /* msg.static := AEAD(k, 0, Si^pub, Hi) */ 1406 wg_algo_aead_enc(wgmi->wgmi_static, sizeof(wgmi->wgmi_static), 1407 cipher_key, 0, wg->wg_pubkey, sizeof(wg->wg_pubkey), 1408 hash, sizeof(hash)); 1409 /* Hi := HASH(Hi || msg.static) */ 1410 wg_algo_hash(hash, wgmi->wgmi_static, sizeof(wgmi->wgmi_static)); 1411 1412 WG_DUMP_HASH48("wgmi_static", wgmi->wgmi_static); 1413 1414 /* [N] 2.2: "ss" */ 1415 /* Ci, k := KDF2(Ci, DH(Si^priv, Sr^pub)) */ 1416 wg_algo_dh_kdf(ckey, cipher_key, wg->wg_privkey, wgp->wgp_pubkey); 1417 1418 /* msg.timestamp := AEAD(k, TIMESTAMP(), Hi) */ 1419 wg_timestamp_t timestamp; 1420 wg_algo_tai64n(timestamp); 1421 wg_algo_aead_enc(wgmi->wgmi_timestamp, sizeof(wgmi->wgmi_timestamp), 1422 cipher_key, 0, timestamp, sizeof(timestamp), hash, sizeof(hash)); 1423 /* Hi := HASH(Hi || msg.timestamp) */ 1424 wg_algo_hash(hash, wgmi->wgmi_timestamp, sizeof(wgmi->wgmi_timestamp)); 1425 1426 /* [W] 5.4.4 Cookie MACs */ 1427 wg_algo_mac_mac1(wgmi->wgmi_mac1, sizeof(wgmi->wgmi_mac1), 1428 wgp->wgp_pubkey, sizeof(wgp->wgp_pubkey), 1429 (const uint8_t *)wgmi, offsetof(struct wg_msg_init, wgmi_mac1)); 1430 /* Need mac1 to decrypt a cookie from a cookie message */ 1431 memcpy(wgp->wgp_last_sent_mac1, wgmi->wgmi_mac1, 1432 sizeof(wgp->wgp_last_sent_mac1)); 1433 wgp->wgp_last_sent_mac1_valid = true; 1434 1435 if (wgp->wgp_latest_cookie_time == 0 || 1436 (time_uptime - wgp->wgp_latest_cookie_time) >= WG_COOKIE_TIME) 1437 memset(wgmi->wgmi_mac2, 0, sizeof(wgmi->wgmi_mac2)); 1438 else { 1439 wg_algo_mac(wgmi->wgmi_mac2, sizeof(wgmi->wgmi_mac2), 1440 wgp->wgp_latest_cookie, WG_COOKIE_LEN, 1441 (const uint8_t *)wgmi, 1442 offsetof(struct wg_msg_init, wgmi_mac2), 1443 NULL, 0); 1444 } 1445 1446 memcpy(wgs->wgs_ephemeral_key_pub, pubkey, sizeof(pubkey)); 1447 memcpy(wgs->wgs_ephemeral_key_priv, privkey, sizeof(privkey)); 1448 memcpy(wgs->wgs_handshake_hash, hash, sizeof(hash)); 1449 memcpy(wgs->wgs_chaining_key, ckey, sizeof(ckey)); 1450 WG_DLOG("%s: sender=%x\n", __func__, wgs->wgs_local_index); 1451 } 1452 1453 static void __noinline 1454 wg_handle_msg_init(struct wg_softc *wg, const struct wg_msg_init *wgmi, 1455 const struct sockaddr *src) 1456 { 1457 uint8_t ckey[WG_CHAINING_KEY_LEN]; /* [W] 5.4.2: Ci */ 1458 uint8_t hash[WG_HASH_LEN]; /* [W] 5.4.2: Hi */ 1459 uint8_t cipher_key[WG_CIPHER_KEY_LEN]; 1460 uint8_t peer_pubkey[WG_STATIC_KEY_LEN]; 1461 struct wg_peer *wgp; 1462 struct wg_session *wgs; 1463 int error, ret; 1464 struct psref psref_peer; 1465 uint8_t mac1[WG_MAC_LEN]; 1466 1467 WG_TRACE("init msg received"); 1468 1469 wg_algo_mac_mac1(mac1, sizeof(mac1), 1470 wg->wg_pubkey, sizeof(wg->wg_pubkey), 1471 (const uint8_t *)wgmi, offsetof(struct wg_msg_init, wgmi_mac1)); 1472 1473 /* 1474 * [W] 5.3: Denial of Service Mitigation & Cookies 1475 * "the responder, ..., must always reject messages with an invalid 1476 * msg.mac1" 1477 */ 1478 if (!consttime_memequal(mac1, wgmi->wgmi_mac1, sizeof(mac1))) { 1479 WG_DLOG("mac1 is invalid\n"); 1480 return; 1481 } 1482 1483 /* 1484 * [W] 5.4.2: First Message: Initiator to Responder 1485 * "When the responder receives this message, it does the same 1486 * operations so that its final state variables are identical, 1487 * replacing the operands of the DH function to produce equivalent 1488 * values." 1489 * Note that the following comments of operations are just copies of 1490 * the initiator's ones. 1491 */ 1492 1493 /* Ci := HASH(CONSTRUCTION) */ 1494 /* Hi := HASH(Ci || IDENTIFIER) */ 1495 wg_init_key_and_hash(ckey, hash); 1496 /* Hi := HASH(Hi || Sr^pub) */ 1497 wg_algo_hash(hash, wg->wg_pubkey, sizeof(wg->wg_pubkey)); 1498 1499 /* [N] 2.2: "e" */ 1500 /* Ci := KDF1(Ci, Ei^pub) */ 1501 wg_algo_kdf(ckey, NULL, NULL, ckey, wgmi->wgmi_ephemeral, 1502 sizeof(wgmi->wgmi_ephemeral)); 1503 /* Hi := HASH(Hi || msg.ephemeral) */ 1504 wg_algo_hash(hash, wgmi->wgmi_ephemeral, sizeof(wgmi->wgmi_ephemeral)); 1505 1506 WG_DUMP_HASH("ckey", ckey); 1507 1508 /* [N] 2.2: "es" */ 1509 /* Ci, k := KDF2(Ci, DH(Ei^priv, Sr^pub)) */ 1510 wg_algo_dh_kdf(ckey, cipher_key, wg->wg_privkey, wgmi->wgmi_ephemeral); 1511 1512 WG_DUMP_HASH48("wgmi_static", wgmi->wgmi_static); 1513 1514 /* [N] 2.2: "s" */ 1515 /* msg.static := AEAD(k, 0, Si^pub, Hi) */ 1516 error = wg_algo_aead_dec(peer_pubkey, WG_STATIC_KEY_LEN, cipher_key, 0, 1517 wgmi->wgmi_static, sizeof(wgmi->wgmi_static), hash, sizeof(hash)); 1518 if (error != 0) { 1519 WG_LOG_RATECHECK(&wg->wg_ppsratecheck, LOG_DEBUG, 1520 "%s: wg_algo_aead_dec for secret key failed\n", 1521 if_name(&wg->wg_if)); 1522 return; 1523 } 1524 /* Hi := HASH(Hi || msg.static) */ 1525 wg_algo_hash(hash, wgmi->wgmi_static, sizeof(wgmi->wgmi_static)); 1526 1527 wgp = wg_lookup_peer_by_pubkey(wg, peer_pubkey, &psref_peer); 1528 if (wgp == NULL) { 1529 WG_DLOG("peer not found\n"); 1530 return; 1531 } 1532 1533 /* 1534 * Lock the peer to serialize access to cookie state. 1535 * 1536 * XXX Can we safely avoid holding the lock across DH? Take it 1537 * just to verify mac2 and then unlock/DH/lock? 1538 */ 1539 mutex_enter(wgp->wgp_lock); 1540 1541 if (__predict_false(wg_is_underload(wg, wgp, WG_MSG_TYPE_INIT))) { 1542 WG_TRACE("under load"); 1543 /* 1544 * [W] 5.3: Denial of Service Mitigation & Cookies 1545 * "the responder, ..., and when under load may reject messages 1546 * with an invalid msg.mac2. If the responder receives a 1547 * message with a valid msg.mac1 yet with an invalid msg.mac2, 1548 * and is under load, it may respond with a cookie reply 1549 * message" 1550 */ 1551 uint8_t zero[WG_MAC_LEN] = {0}; 1552 if (consttime_memequal(wgmi->wgmi_mac2, zero, sizeof(zero))) { 1553 WG_TRACE("sending a cookie message: no cookie included"); 1554 (void)wg_send_cookie_msg(wg, wgp, wgmi->wgmi_sender, 1555 wgmi->wgmi_mac1, src); 1556 goto out; 1557 } 1558 if (!wgp->wgp_last_sent_cookie_valid) { 1559 WG_TRACE("sending a cookie message: no cookie sent ever"); 1560 (void)wg_send_cookie_msg(wg, wgp, wgmi->wgmi_sender, 1561 wgmi->wgmi_mac1, src); 1562 goto out; 1563 } 1564 uint8_t mac2[WG_MAC_LEN]; 1565 wg_algo_mac(mac2, sizeof(mac2), wgp->wgp_last_sent_cookie, 1566 WG_COOKIE_LEN, (const uint8_t *)wgmi, 1567 offsetof(struct wg_msg_init, wgmi_mac2), NULL, 0); 1568 if (!consttime_memequal(mac2, wgmi->wgmi_mac2, sizeof(mac2))) { 1569 WG_DLOG("mac2 is invalid\n"); 1570 goto out; 1571 } 1572 WG_TRACE("under load, but continue to sending"); 1573 } 1574 1575 /* [N] 2.2: "ss" */ 1576 /* Ci, k := KDF2(Ci, DH(Si^priv, Sr^pub)) */ 1577 wg_algo_dh_kdf(ckey, cipher_key, wg->wg_privkey, wgp->wgp_pubkey); 1578 1579 /* msg.timestamp := AEAD(k, TIMESTAMP(), Hi) */ 1580 wg_timestamp_t timestamp; 1581 error = wg_algo_aead_dec(timestamp, sizeof(timestamp), cipher_key, 0, 1582 wgmi->wgmi_timestamp, sizeof(wgmi->wgmi_timestamp), 1583 hash, sizeof(hash)); 1584 if (error != 0) { 1585 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 1586 "%s: peer %s: wg_algo_aead_dec for timestamp failed\n", 1587 if_name(&wg->wg_if), wgp->wgp_name); 1588 goto out; 1589 } 1590 /* Hi := HASH(Hi || msg.timestamp) */ 1591 wg_algo_hash(hash, wgmi->wgmi_timestamp, sizeof(wgmi->wgmi_timestamp)); 1592 1593 /* 1594 * [W] 5.1 "The responder keeps track of the greatest timestamp 1595 * received per peer and discards packets containing 1596 * timestamps less than or equal to it." 1597 */ 1598 ret = memcmp(timestamp, wgp->wgp_timestamp_latest_init, 1599 sizeof(timestamp)); 1600 if (ret <= 0) { 1601 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 1602 "%s: peer %s: invalid init msg: timestamp is old\n", 1603 if_name(&wg->wg_if), wgp->wgp_name); 1604 goto out; 1605 } 1606 memcpy(wgp->wgp_timestamp_latest_init, timestamp, sizeof(timestamp)); 1607 1608 /* 1609 * Message is good -- we're committing to handle it now, unless 1610 * we were already initiating a session. 1611 */ 1612 wgs = wgp->wgp_session_unstable; 1613 switch (wgs->wgs_state) { 1614 case WGS_STATE_UNKNOWN: /* new session initiated by peer */ 1615 wg_get_session_index(wg, wgs); 1616 break; 1617 case WGS_STATE_INIT_ACTIVE: /* we're already initiating, drop */ 1618 WG_TRACE("Session already initializing, ignoring the message"); 1619 goto out; 1620 case WGS_STATE_INIT_PASSIVE: /* peer is retrying, start over */ 1621 WG_TRACE("Session already initializing, destroying old states"); 1622 wg_clear_states(wgs); 1623 /* keep session index */ 1624 break; 1625 case WGS_STATE_ESTABLISHED: /* can't happen */ 1626 panic("unstable session can't be established"); 1627 break; 1628 case WGS_STATE_DESTROYING: /* rekey initiated by peer */ 1629 WG_TRACE("Session destroying, but force to clear"); 1630 callout_stop(&wgp->wgp_session_dtor_timer); 1631 wg_clear_states(wgs); 1632 /* keep session index */ 1633 break; 1634 default: 1635 panic("invalid session state: %d", wgs->wgs_state); 1636 } 1637 wgs->wgs_state = WGS_STATE_INIT_PASSIVE; 1638 1639 memcpy(wgs->wgs_handshake_hash, hash, sizeof(hash)); 1640 memcpy(wgs->wgs_chaining_key, ckey, sizeof(ckey)); 1641 memcpy(wgs->wgs_ephemeral_key_peer, wgmi->wgmi_ephemeral, 1642 sizeof(wgmi->wgmi_ephemeral)); 1643 1644 wg_update_endpoint_if_necessary(wgp, src); 1645 1646 (void)wg_send_handshake_msg_resp(wg, wgp, wgs, wgmi); 1647 1648 wg_calculate_keys(wgs, false); 1649 wg_clear_states(wgs); 1650 1651 out: 1652 mutex_exit(wgp->wgp_lock); 1653 wg_put_peer(wgp, &psref_peer); 1654 } 1655 1656 static struct socket * 1657 wg_get_so_by_af(struct wg_softc *wg, const int af) 1658 { 1659 1660 switch (af) { 1661 #ifdef INET 1662 case AF_INET: 1663 return wg->wg_so4; 1664 #endif 1665 #ifdef INET6 1666 case AF_INET6: 1667 return wg->wg_so6; 1668 #endif 1669 default: 1670 panic("wg: no such af: %d", af); 1671 } 1672 } 1673 1674 static struct socket * 1675 wg_get_so_by_peer(struct wg_peer *wgp, struct wg_sockaddr *wgsa) 1676 { 1677 1678 return wg_get_so_by_af(wgp->wgp_sc, wgsa_family(wgsa)); 1679 } 1680 1681 static struct wg_sockaddr * 1682 wg_get_endpoint_sa(struct wg_peer *wgp, struct psref *psref) 1683 { 1684 struct wg_sockaddr *wgsa; 1685 int s; 1686 1687 s = pserialize_read_enter(); 1688 wgsa = atomic_load_consume(&wgp->wgp_endpoint); 1689 psref_acquire(psref, &wgsa->wgsa_psref, wg_psref_class); 1690 pserialize_read_exit(s); 1691 1692 return wgsa; 1693 } 1694 1695 static void 1696 wg_put_sa(struct wg_peer *wgp, struct wg_sockaddr *wgsa, struct psref *psref) 1697 { 1698 1699 psref_release(psref, &wgsa->wgsa_psref, wg_psref_class); 1700 } 1701 1702 static int 1703 wg_send_so(struct wg_peer *wgp, struct mbuf *m) 1704 { 1705 int error; 1706 struct socket *so; 1707 struct psref psref; 1708 struct wg_sockaddr *wgsa; 1709 1710 wgsa = wg_get_endpoint_sa(wgp, &psref); 1711 so = wg_get_so_by_peer(wgp, wgsa); 1712 error = sosend(so, wgsatosa(wgsa), NULL, m, NULL, 0, curlwp); 1713 wg_put_sa(wgp, wgsa, &psref); 1714 1715 return error; 1716 } 1717 1718 static int 1719 wg_send_handshake_msg_init(struct wg_softc *wg, struct wg_peer *wgp) 1720 { 1721 int error; 1722 struct mbuf *m; 1723 struct wg_msg_init *wgmi; 1724 struct wg_session *wgs; 1725 1726 KASSERT(mutex_owned(wgp->wgp_lock)); 1727 1728 wgs = wgp->wgp_session_unstable; 1729 /* XXX pull dispatch out into wg_task_send_init_message */ 1730 switch (wgs->wgs_state) { 1731 case WGS_STATE_UNKNOWN: /* new session initiated by us */ 1732 wg_get_session_index(wg, wgs); 1733 break; 1734 case WGS_STATE_INIT_ACTIVE: /* we're already initiating, stop */ 1735 WG_TRACE("Session already initializing, skip starting new one"); 1736 return EBUSY; 1737 case WGS_STATE_INIT_PASSIVE: /* peer was trying -- XXX what now? */ 1738 WG_TRACE("Session already initializing, destroying old states"); 1739 wg_clear_states(wgs); 1740 /* keep session index */ 1741 break; 1742 case WGS_STATE_ESTABLISHED: /* can't happen */ 1743 panic("unstable session can't be established"); 1744 break; 1745 case WGS_STATE_DESTROYING: /* rekey initiated by us too early */ 1746 WG_TRACE("Session destroying"); 1747 /* XXX should wait? */ 1748 return EBUSY; 1749 } 1750 wgs->wgs_state = WGS_STATE_INIT_ACTIVE; 1751 1752 m = m_gethdr(M_WAIT, MT_DATA); 1753 if (sizeof(*wgmi) > MHLEN) { 1754 m_clget(m, M_WAIT); 1755 CTASSERT(sizeof(*wgmi) <= MCLBYTES); 1756 } 1757 m->m_pkthdr.len = m->m_len = sizeof(*wgmi); 1758 wgmi = mtod(m, struct wg_msg_init *); 1759 wg_fill_msg_init(wg, wgp, wgs, wgmi); 1760 1761 error = wg->wg_ops->send_hs_msg(wgp, m); 1762 if (error == 0) { 1763 WG_TRACE("init msg sent"); 1764 1765 if (wgp->wgp_handshake_start_time == 0) 1766 wgp->wgp_handshake_start_time = time_uptime; 1767 callout_schedule(&wgp->wgp_handshake_timeout_timer, 1768 MIN(wg_rekey_timeout, (unsigned)(INT_MAX / hz)) * hz); 1769 } else { 1770 wg_put_session_index(wg, wgs); 1771 /* Initiation failed; toss packet waiting for it if any. */ 1772 m = atomic_swap_ptr(&wgp->wgp_pending, NULL); 1773 m_freem(m); 1774 } 1775 1776 return error; 1777 } 1778 1779 static void 1780 wg_fill_msg_resp(struct wg_softc *wg, struct wg_peer *wgp, 1781 struct wg_session *wgs, struct wg_msg_resp *wgmr, 1782 const struct wg_msg_init *wgmi) 1783 { 1784 uint8_t ckey[WG_CHAINING_KEY_LEN]; /* [W] 5.4.3: Cr */ 1785 uint8_t hash[WG_HASH_LEN]; /* [W] 5.4.3: Hr */ 1786 uint8_t cipher_key[WG_KDF_OUTPUT_LEN]; 1787 uint8_t pubkey[WG_EPHEMERAL_KEY_LEN]; 1788 uint8_t privkey[WG_EPHEMERAL_KEY_LEN]; 1789 1790 KASSERT(mutex_owned(wgp->wgp_lock)); 1791 KASSERT(wgs == wgp->wgp_session_unstable); 1792 KASSERT(wgs->wgs_state == WGS_STATE_INIT_PASSIVE); 1793 1794 memcpy(hash, wgs->wgs_handshake_hash, sizeof(hash)); 1795 memcpy(ckey, wgs->wgs_chaining_key, sizeof(ckey)); 1796 1797 wgmr->wgmr_type = htole32(WG_MSG_TYPE_RESP); 1798 wgmr->wgmr_sender = wgs->wgs_local_index; 1799 wgmr->wgmr_receiver = wgmi->wgmi_sender; 1800 1801 /* [W] 5.4.3 Second Message: Responder to Initiator */ 1802 1803 /* [N] 2.2: "e" */ 1804 /* Er^priv, Er^pub := DH-GENERATE() */ 1805 wg_algo_generate_keypair(pubkey, privkey); 1806 /* Cr := KDF1(Cr, Er^pub) */ 1807 wg_algo_kdf(ckey, NULL, NULL, ckey, pubkey, sizeof(pubkey)); 1808 /* msg.ephemeral := Er^pub */ 1809 memcpy(wgmr->wgmr_ephemeral, pubkey, sizeof(wgmr->wgmr_ephemeral)); 1810 /* Hr := HASH(Hr || msg.ephemeral) */ 1811 wg_algo_hash(hash, pubkey, sizeof(pubkey)); 1812 1813 WG_DUMP_HASH("ckey", ckey); 1814 WG_DUMP_HASH("hash", hash); 1815 1816 /* [N] 2.2: "ee" */ 1817 /* Cr := KDF1(Cr, DH(Er^priv, Ei^pub)) */ 1818 wg_algo_dh_kdf(ckey, NULL, privkey, wgs->wgs_ephemeral_key_peer); 1819 1820 /* [N] 2.2: "se" */ 1821 /* Cr := KDF1(Cr, DH(Er^priv, Si^pub)) */ 1822 wg_algo_dh_kdf(ckey, NULL, privkey, wgp->wgp_pubkey); 1823 1824 /* [N] 9.2: "psk" */ 1825 { 1826 uint8_t kdfout[WG_KDF_OUTPUT_LEN]; 1827 /* Cr, r, k := KDF3(Cr, Q) */ 1828 wg_algo_kdf(ckey, kdfout, cipher_key, ckey, wgp->wgp_psk, 1829 sizeof(wgp->wgp_psk)); 1830 /* Hr := HASH(Hr || r) */ 1831 wg_algo_hash(hash, kdfout, sizeof(kdfout)); 1832 } 1833 1834 /* msg.empty := AEAD(k, 0, e, Hr) */ 1835 wg_algo_aead_enc(wgmr->wgmr_empty, sizeof(wgmr->wgmr_empty), 1836 cipher_key, 0, NULL, 0, hash, sizeof(hash)); 1837 /* Hr := HASH(Hr || msg.empty) */ 1838 wg_algo_hash(hash, wgmr->wgmr_empty, sizeof(wgmr->wgmr_empty)); 1839 1840 WG_DUMP_HASH("wgmr_empty", wgmr->wgmr_empty); 1841 1842 /* [W] 5.4.4: Cookie MACs */ 1843 /* msg.mac1 := MAC(HASH(LABEL-MAC1 || Sm'^pub), msg_a) */ 1844 wg_algo_mac_mac1(wgmr->wgmr_mac1, sizeof(wgmi->wgmi_mac1), 1845 wgp->wgp_pubkey, sizeof(wgp->wgp_pubkey), 1846 (const uint8_t *)wgmr, offsetof(struct wg_msg_resp, wgmr_mac1)); 1847 /* Need mac1 to decrypt a cookie from a cookie message */ 1848 memcpy(wgp->wgp_last_sent_mac1, wgmr->wgmr_mac1, 1849 sizeof(wgp->wgp_last_sent_mac1)); 1850 wgp->wgp_last_sent_mac1_valid = true; 1851 1852 if (wgp->wgp_latest_cookie_time == 0 || 1853 (time_uptime - wgp->wgp_latest_cookie_time) >= WG_COOKIE_TIME) 1854 /* msg.mac2 := 0^16 */ 1855 memset(wgmr->wgmr_mac2, 0, sizeof(wgmr->wgmr_mac2)); 1856 else { 1857 /* msg.mac2 := MAC(Lm, msg_b) */ 1858 wg_algo_mac(wgmr->wgmr_mac2, sizeof(wgmi->wgmi_mac2), 1859 wgp->wgp_latest_cookie, WG_COOKIE_LEN, 1860 (const uint8_t *)wgmr, 1861 offsetof(struct wg_msg_resp, wgmr_mac2), 1862 NULL, 0); 1863 } 1864 1865 memcpy(wgs->wgs_handshake_hash, hash, sizeof(hash)); 1866 memcpy(wgs->wgs_chaining_key, ckey, sizeof(ckey)); 1867 memcpy(wgs->wgs_ephemeral_key_pub, pubkey, sizeof(pubkey)); 1868 memcpy(wgs->wgs_ephemeral_key_priv, privkey, sizeof(privkey)); 1869 wgs->wgs_remote_index = wgmi->wgmi_sender; 1870 WG_DLOG("sender=%x\n", wgs->wgs_local_index); 1871 WG_DLOG("receiver=%x\n", wgs->wgs_remote_index); 1872 } 1873 1874 static void 1875 wg_swap_sessions(struct wg_peer *wgp) 1876 { 1877 struct wg_session *wgs, *wgs_prev; 1878 1879 KASSERT(mutex_owned(wgp->wgp_lock)); 1880 1881 wgs = wgp->wgp_session_unstable; 1882 KASSERT(wgs->wgs_state == WGS_STATE_ESTABLISHED); 1883 1884 wgs_prev = wgp->wgp_session_stable; 1885 KASSERT(wgs_prev->wgs_state == WGS_STATE_ESTABLISHED || 1886 wgs_prev->wgs_state == WGS_STATE_UNKNOWN); 1887 atomic_store_release(&wgp->wgp_session_stable, wgs); 1888 wgp->wgp_session_unstable = wgs_prev; 1889 } 1890 1891 static void __noinline 1892 wg_handle_msg_resp(struct wg_softc *wg, const struct wg_msg_resp *wgmr, 1893 const struct sockaddr *src) 1894 { 1895 uint8_t ckey[WG_CHAINING_KEY_LEN]; /* [W] 5.4.3: Cr */ 1896 uint8_t hash[WG_HASH_LEN]; /* [W] 5.4.3: Kr */ 1897 uint8_t cipher_key[WG_KDF_OUTPUT_LEN]; 1898 struct wg_peer *wgp; 1899 struct wg_session *wgs; 1900 struct psref psref; 1901 int error; 1902 uint8_t mac1[WG_MAC_LEN]; 1903 struct wg_session *wgs_prev; 1904 struct mbuf *m; 1905 1906 wg_algo_mac_mac1(mac1, sizeof(mac1), 1907 wg->wg_pubkey, sizeof(wg->wg_pubkey), 1908 (const uint8_t *)wgmr, offsetof(struct wg_msg_resp, wgmr_mac1)); 1909 1910 /* 1911 * [W] 5.3: Denial of Service Mitigation & Cookies 1912 * "the responder, ..., must always reject messages with an invalid 1913 * msg.mac1" 1914 */ 1915 if (!consttime_memequal(mac1, wgmr->wgmr_mac1, sizeof(mac1))) { 1916 WG_DLOG("mac1 is invalid\n"); 1917 return; 1918 } 1919 1920 WG_TRACE("resp msg received"); 1921 wgs = wg_lookup_session_by_index(wg, wgmr->wgmr_receiver, &psref); 1922 if (wgs == NULL) { 1923 WG_TRACE("No session found"); 1924 return; 1925 } 1926 1927 wgp = wgs->wgs_peer; 1928 1929 mutex_enter(wgp->wgp_lock); 1930 1931 /* If we weren't waiting for a handshake response, drop it. */ 1932 if (wgs->wgs_state != WGS_STATE_INIT_ACTIVE) { 1933 WG_TRACE("peer sent spurious handshake response, ignoring"); 1934 goto out; 1935 } 1936 1937 if (__predict_false(wg_is_underload(wg, wgp, WG_MSG_TYPE_RESP))) { 1938 WG_TRACE("under load"); 1939 /* 1940 * [W] 5.3: Denial of Service Mitigation & Cookies 1941 * "the responder, ..., and when under load may reject messages 1942 * with an invalid msg.mac2. If the responder receives a 1943 * message with a valid msg.mac1 yet with an invalid msg.mac2, 1944 * and is under load, it may respond with a cookie reply 1945 * message" 1946 */ 1947 uint8_t zero[WG_MAC_LEN] = {0}; 1948 if (consttime_memequal(wgmr->wgmr_mac2, zero, sizeof(zero))) { 1949 WG_TRACE("sending a cookie message: no cookie included"); 1950 (void)wg_send_cookie_msg(wg, wgp, wgmr->wgmr_sender, 1951 wgmr->wgmr_mac1, src); 1952 goto out; 1953 } 1954 if (!wgp->wgp_last_sent_cookie_valid) { 1955 WG_TRACE("sending a cookie message: no cookie sent ever"); 1956 (void)wg_send_cookie_msg(wg, wgp, wgmr->wgmr_sender, 1957 wgmr->wgmr_mac1, src); 1958 goto out; 1959 } 1960 uint8_t mac2[WG_MAC_LEN]; 1961 wg_algo_mac(mac2, sizeof(mac2), wgp->wgp_last_sent_cookie, 1962 WG_COOKIE_LEN, (const uint8_t *)wgmr, 1963 offsetof(struct wg_msg_resp, wgmr_mac2), NULL, 0); 1964 if (!consttime_memequal(mac2, wgmr->wgmr_mac2, sizeof(mac2))) { 1965 WG_DLOG("mac2 is invalid\n"); 1966 goto out; 1967 } 1968 WG_TRACE("under load, but continue to sending"); 1969 } 1970 1971 memcpy(hash, wgs->wgs_handshake_hash, sizeof(hash)); 1972 memcpy(ckey, wgs->wgs_chaining_key, sizeof(ckey)); 1973 1974 /* 1975 * [W] 5.4.3 Second Message: Responder to Initiator 1976 * "When the initiator receives this message, it does the same 1977 * operations so that its final state variables are identical, 1978 * replacing the operands of the DH function to produce equivalent 1979 * values." 1980 * Note that the following comments of operations are just copies of 1981 * the initiator's ones. 1982 */ 1983 1984 /* [N] 2.2: "e" */ 1985 /* Cr := KDF1(Cr, Er^pub) */ 1986 wg_algo_kdf(ckey, NULL, NULL, ckey, wgmr->wgmr_ephemeral, 1987 sizeof(wgmr->wgmr_ephemeral)); 1988 /* Hr := HASH(Hr || msg.ephemeral) */ 1989 wg_algo_hash(hash, wgmr->wgmr_ephemeral, sizeof(wgmr->wgmr_ephemeral)); 1990 1991 WG_DUMP_HASH("ckey", ckey); 1992 WG_DUMP_HASH("hash", hash); 1993 1994 /* [N] 2.2: "ee" */ 1995 /* Cr := KDF1(Cr, DH(Er^priv, Ei^pub)) */ 1996 wg_algo_dh_kdf(ckey, NULL, wgs->wgs_ephemeral_key_priv, 1997 wgmr->wgmr_ephemeral); 1998 1999 /* [N] 2.2: "se" */ 2000 /* Cr := KDF1(Cr, DH(Er^priv, Si^pub)) */ 2001 wg_algo_dh_kdf(ckey, NULL, wg->wg_privkey, wgmr->wgmr_ephemeral); 2002 2003 /* [N] 9.2: "psk" */ 2004 { 2005 uint8_t kdfout[WG_KDF_OUTPUT_LEN]; 2006 /* Cr, r, k := KDF3(Cr, Q) */ 2007 wg_algo_kdf(ckey, kdfout, cipher_key, ckey, wgp->wgp_psk, 2008 sizeof(wgp->wgp_psk)); 2009 /* Hr := HASH(Hr || r) */ 2010 wg_algo_hash(hash, kdfout, sizeof(kdfout)); 2011 } 2012 2013 { 2014 uint8_t out[sizeof(wgmr->wgmr_empty)]; /* for safety */ 2015 /* msg.empty := AEAD(k, 0, e, Hr) */ 2016 error = wg_algo_aead_dec(out, 0, cipher_key, 0, wgmr->wgmr_empty, 2017 sizeof(wgmr->wgmr_empty), hash, sizeof(hash)); 2018 WG_DUMP_HASH("wgmr_empty", wgmr->wgmr_empty); 2019 if (error != 0) { 2020 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 2021 "%s: peer %s: wg_algo_aead_dec for empty message failed\n", 2022 if_name(&wg->wg_if), wgp->wgp_name); 2023 goto out; 2024 } 2025 /* Hr := HASH(Hr || msg.empty) */ 2026 wg_algo_hash(hash, wgmr->wgmr_empty, sizeof(wgmr->wgmr_empty)); 2027 } 2028 2029 memcpy(wgs->wgs_handshake_hash, hash, sizeof(wgs->wgs_handshake_hash)); 2030 memcpy(wgs->wgs_chaining_key, ckey, sizeof(wgs->wgs_chaining_key)); 2031 wgs->wgs_remote_index = wgmr->wgmr_sender; 2032 WG_DLOG("receiver=%x\n", wgs->wgs_remote_index); 2033 2034 KASSERT(wgs->wgs_state == WGS_STATE_INIT_ACTIVE); 2035 wgs->wgs_state = WGS_STATE_ESTABLISHED; 2036 wgs->wgs_time_established = time_uptime; 2037 wgs->wgs_time_last_data_sent = 0; 2038 wgs->wgs_is_initiator = true; 2039 wg_calculate_keys(wgs, true); 2040 wg_clear_states(wgs); 2041 WG_TRACE("WGS_STATE_ESTABLISHED"); 2042 2043 callout_stop(&wgp->wgp_handshake_timeout_timer); 2044 2045 wg_swap_sessions(wgp); 2046 KASSERT(wgs == wgp->wgp_session_stable); 2047 wgs_prev = wgp->wgp_session_unstable; 2048 getnanotime(&wgp->wgp_last_handshake_time); 2049 wgp->wgp_handshake_start_time = 0; 2050 wgp->wgp_last_sent_mac1_valid = false; 2051 wgp->wgp_last_sent_cookie_valid = false; 2052 2053 wg_schedule_rekey_timer(wgp); 2054 2055 wg_update_endpoint_if_necessary(wgp, src); 2056 2057 /* 2058 * If we had a data packet queued up, send it; otherwise send a 2059 * keepalive message -- either way we have to send something 2060 * immediately or else the responder will never answer. 2061 */ 2062 if ((m = atomic_swap_ptr(&wgp->wgp_pending, NULL)) != NULL) { 2063 kpreempt_disable(); 2064 const uint32_t h = curcpu()->ci_index; // pktq_rps_hash(m) 2065 M_SETCTX(m, wgp); 2066 if (__predict_false(!pktq_enqueue(wg_pktq, m, h))) { 2067 WGLOG(LOG_ERR, "%s: pktq full, dropping\n", 2068 if_name(&wg->wg_if)); 2069 m_freem(m); 2070 } 2071 kpreempt_enable(); 2072 } else { 2073 wg_send_keepalive_msg(wgp, wgs); 2074 } 2075 2076 if (wgs_prev->wgs_state == WGS_STATE_ESTABLISHED) { 2077 /* Wait for wg_get_stable_session to drain. */ 2078 pserialize_perform(wgp->wgp_psz); 2079 2080 /* Transition ESTABLISHED->DESTROYING. */ 2081 wgs_prev->wgs_state = WGS_STATE_DESTROYING; 2082 2083 /* We can't destroy the old session immediately */ 2084 wg_schedule_session_dtor_timer(wgp); 2085 } else { 2086 KASSERTMSG(wgs_prev->wgs_state == WGS_STATE_UNKNOWN, 2087 "state=%d", wgs_prev->wgs_state); 2088 } 2089 2090 out: 2091 mutex_exit(wgp->wgp_lock); 2092 wg_put_session(wgs, &psref); 2093 } 2094 2095 static int 2096 wg_send_handshake_msg_resp(struct wg_softc *wg, struct wg_peer *wgp, 2097 struct wg_session *wgs, const struct wg_msg_init *wgmi) 2098 { 2099 int error; 2100 struct mbuf *m; 2101 struct wg_msg_resp *wgmr; 2102 2103 KASSERT(mutex_owned(wgp->wgp_lock)); 2104 KASSERT(wgs == wgp->wgp_session_unstable); 2105 KASSERT(wgs->wgs_state == WGS_STATE_INIT_PASSIVE); 2106 2107 m = m_gethdr(M_WAIT, MT_DATA); 2108 if (sizeof(*wgmr) > MHLEN) { 2109 m_clget(m, M_WAIT); 2110 CTASSERT(sizeof(*wgmr) <= MCLBYTES); 2111 } 2112 m->m_pkthdr.len = m->m_len = sizeof(*wgmr); 2113 wgmr = mtod(m, struct wg_msg_resp *); 2114 wg_fill_msg_resp(wg, wgp, wgs, wgmr, wgmi); 2115 2116 error = wg->wg_ops->send_hs_msg(wgp, m); 2117 if (error == 0) 2118 WG_TRACE("resp msg sent"); 2119 return error; 2120 } 2121 2122 static struct wg_peer * 2123 wg_lookup_peer_by_pubkey(struct wg_softc *wg, 2124 const uint8_t pubkey[WG_STATIC_KEY_LEN], struct psref *psref) 2125 { 2126 struct wg_peer *wgp; 2127 2128 int s = pserialize_read_enter(); 2129 wgp = thmap_get(wg->wg_peers_bypubkey, pubkey, WG_STATIC_KEY_LEN); 2130 if (wgp != NULL) 2131 wg_get_peer(wgp, psref); 2132 pserialize_read_exit(s); 2133 2134 return wgp; 2135 } 2136 2137 static void 2138 wg_fill_msg_cookie(struct wg_softc *wg, struct wg_peer *wgp, 2139 struct wg_msg_cookie *wgmc, const uint32_t sender, 2140 const uint8_t mac1[WG_MAC_LEN], const struct sockaddr *src) 2141 { 2142 uint8_t cookie[WG_COOKIE_LEN]; 2143 uint8_t key[WG_HASH_LEN]; 2144 uint8_t addr[sizeof(struct in6_addr)]; 2145 size_t addrlen; 2146 uint16_t uh_sport; /* be */ 2147 2148 KASSERT(mutex_owned(wgp->wgp_lock)); 2149 2150 wgmc->wgmc_type = htole32(WG_MSG_TYPE_COOKIE); 2151 wgmc->wgmc_receiver = sender; 2152 cprng_fast(wgmc->wgmc_salt, sizeof(wgmc->wgmc_salt)); 2153 2154 /* 2155 * [W] 5.4.7: Under Load: Cookie Reply Message 2156 * "The secret variable, Rm, changes every two minutes to a 2157 * random value" 2158 */ 2159 if ((time_uptime - wgp->wgp_last_genrandval_time) > WG_RANDVAL_TIME) { 2160 wgp->wgp_randval = cprng_strong32(); 2161 wgp->wgp_last_genrandval_time = time_uptime; 2162 } 2163 2164 switch (src->sa_family) { 2165 case AF_INET: { 2166 const struct sockaddr_in *sin = satocsin(src); 2167 addrlen = sizeof(sin->sin_addr); 2168 memcpy(addr, &sin->sin_addr, addrlen); 2169 uh_sport = sin->sin_port; 2170 break; 2171 } 2172 #ifdef INET6 2173 case AF_INET6: { 2174 const struct sockaddr_in6 *sin6 = satocsin6(src); 2175 addrlen = sizeof(sin6->sin6_addr); 2176 memcpy(addr, &sin6->sin6_addr, addrlen); 2177 uh_sport = sin6->sin6_port; 2178 break; 2179 } 2180 #endif 2181 default: 2182 panic("invalid af=%d", src->sa_family); 2183 } 2184 2185 wg_algo_mac(cookie, sizeof(cookie), 2186 (const uint8_t *)&wgp->wgp_randval, sizeof(wgp->wgp_randval), 2187 addr, addrlen, (const uint8_t *)&uh_sport, sizeof(uh_sport)); 2188 wg_algo_mac_cookie(key, sizeof(key), wg->wg_pubkey, 2189 sizeof(wg->wg_pubkey)); 2190 wg_algo_xaead_enc(wgmc->wgmc_cookie, sizeof(wgmc->wgmc_cookie), key, 2191 cookie, sizeof(cookie), mac1, WG_MAC_LEN, wgmc->wgmc_salt); 2192 2193 /* Need to store to calculate mac2 */ 2194 memcpy(wgp->wgp_last_sent_cookie, cookie, sizeof(cookie)); 2195 wgp->wgp_last_sent_cookie_valid = true; 2196 } 2197 2198 static int 2199 wg_send_cookie_msg(struct wg_softc *wg, struct wg_peer *wgp, 2200 const uint32_t sender, const uint8_t mac1[WG_MAC_LEN], 2201 const struct sockaddr *src) 2202 { 2203 int error; 2204 struct mbuf *m; 2205 struct wg_msg_cookie *wgmc; 2206 2207 KASSERT(mutex_owned(wgp->wgp_lock)); 2208 2209 m = m_gethdr(M_WAIT, MT_DATA); 2210 if (sizeof(*wgmc) > MHLEN) { 2211 m_clget(m, M_WAIT); 2212 CTASSERT(sizeof(*wgmc) <= MCLBYTES); 2213 } 2214 m->m_pkthdr.len = m->m_len = sizeof(*wgmc); 2215 wgmc = mtod(m, struct wg_msg_cookie *); 2216 wg_fill_msg_cookie(wg, wgp, wgmc, sender, mac1, src); 2217 2218 error = wg->wg_ops->send_hs_msg(wgp, m); 2219 if (error == 0) 2220 WG_TRACE("cookie msg sent"); 2221 return error; 2222 } 2223 2224 static bool 2225 wg_is_underload(struct wg_softc *wg, struct wg_peer *wgp, int msgtype) 2226 { 2227 #ifdef WG_DEBUG_PARAMS 2228 if (wg_force_underload) 2229 return true; 2230 #endif 2231 2232 /* 2233 * XXX we don't have a means of a load estimation. The purpose of 2234 * the mechanism is a DoS mitigation, so we consider frequent handshake 2235 * messages as (a kind of) load; if a message of the same type comes 2236 * to a peer within 1 second, we consider we are under load. 2237 */ 2238 time_t last = wgp->wgp_last_msg_received_time[msgtype]; 2239 wgp->wgp_last_msg_received_time[msgtype] = time_uptime; 2240 return (time_uptime - last) == 0; 2241 } 2242 2243 static void 2244 wg_calculate_keys(struct wg_session *wgs, const bool initiator) 2245 { 2246 2247 KASSERT(mutex_owned(wgs->wgs_peer->wgp_lock)); 2248 2249 /* 2250 * [W] 5.4.5: Ti^send = Tr^recv, Ti^recv = Tr^send := KDF2(Ci = Cr, e) 2251 */ 2252 if (initiator) { 2253 wg_algo_kdf(wgs->wgs_tkey_send, wgs->wgs_tkey_recv, NULL, 2254 wgs->wgs_chaining_key, NULL, 0); 2255 } else { 2256 wg_algo_kdf(wgs->wgs_tkey_recv, wgs->wgs_tkey_send, NULL, 2257 wgs->wgs_chaining_key, NULL, 0); 2258 } 2259 WG_DUMP_HASH("wgs_tkey_send", wgs->wgs_tkey_send); 2260 WG_DUMP_HASH("wgs_tkey_recv", wgs->wgs_tkey_recv); 2261 } 2262 2263 static uint64_t 2264 wg_session_get_send_counter(struct wg_session *wgs) 2265 { 2266 #ifdef __HAVE_ATOMIC64_LOADSTORE 2267 return atomic_load_relaxed(&wgs->wgs_send_counter); 2268 #else 2269 uint64_t send_counter; 2270 2271 mutex_enter(&wgs->wgs_send_counter_lock); 2272 send_counter = wgs->wgs_send_counter; 2273 mutex_exit(&wgs->wgs_send_counter_lock); 2274 2275 return send_counter; 2276 #endif 2277 } 2278 2279 static uint64_t 2280 wg_session_inc_send_counter(struct wg_session *wgs) 2281 { 2282 #ifdef __HAVE_ATOMIC64_LOADSTORE 2283 return atomic_inc_64_nv(&wgs->wgs_send_counter) - 1; 2284 #else 2285 uint64_t send_counter; 2286 2287 mutex_enter(&wgs->wgs_send_counter_lock); 2288 send_counter = wgs->wgs_send_counter++; 2289 mutex_exit(&wgs->wgs_send_counter_lock); 2290 2291 return send_counter; 2292 #endif 2293 } 2294 2295 static void 2296 wg_clear_states(struct wg_session *wgs) 2297 { 2298 2299 KASSERT(mutex_owned(wgs->wgs_peer->wgp_lock)); 2300 2301 wgs->wgs_send_counter = 0; 2302 sliwin_reset(&wgs->wgs_recvwin->window); 2303 2304 #define wgs_clear(v) explicit_memset(wgs->wgs_##v, 0, sizeof(wgs->wgs_##v)) 2305 wgs_clear(handshake_hash); 2306 wgs_clear(chaining_key); 2307 wgs_clear(ephemeral_key_pub); 2308 wgs_clear(ephemeral_key_priv); 2309 wgs_clear(ephemeral_key_peer); 2310 #undef wgs_clear 2311 } 2312 2313 static struct wg_session * 2314 wg_lookup_session_by_index(struct wg_softc *wg, const uint32_t index, 2315 struct psref *psref) 2316 { 2317 struct wg_session *wgs; 2318 2319 int s = pserialize_read_enter(); 2320 wgs = thmap_get(wg->wg_sessions_byindex, &index, sizeof index); 2321 if (wgs != NULL) { 2322 KASSERT(atomic_load_relaxed(&wgs->wgs_state) != 2323 WGS_STATE_UNKNOWN); 2324 psref_acquire(psref, &wgs->wgs_psref, wg_psref_class); 2325 } 2326 pserialize_read_exit(s); 2327 2328 return wgs; 2329 } 2330 2331 static void 2332 wg_schedule_rekey_timer(struct wg_peer *wgp) 2333 { 2334 int timeout = MIN(wg_rekey_after_time, (unsigned)(INT_MAX / hz)); 2335 2336 callout_schedule(&wgp->wgp_rekey_timer, timeout * hz); 2337 } 2338 2339 static void 2340 wg_send_keepalive_msg(struct wg_peer *wgp, struct wg_session *wgs) 2341 { 2342 struct mbuf *m; 2343 2344 /* 2345 * [W] 6.5 Passive Keepalive 2346 * "A keepalive message is simply a transport data message with 2347 * a zero-length encapsulated encrypted inner-packet." 2348 */ 2349 WG_TRACE(""); 2350 m = m_gethdr(M_WAIT, MT_DATA); 2351 wg_send_data_msg(wgp, wgs, m); 2352 } 2353 2354 static bool 2355 wg_need_to_send_init_message(struct wg_session *wgs) 2356 { 2357 /* 2358 * [W] 6.2 Transport Message Limits 2359 * "if a peer is the initiator of a current secure session, 2360 * WireGuard will send a handshake initiation message to begin 2361 * a new secure session ... if after receiving a transport data 2362 * message, the current secure session is (REJECT-AFTER-TIME 2363 * KEEPALIVE-TIMEOUT REKEY-TIMEOUT) seconds old and it has 2364 * not yet acted upon this event." 2365 */ 2366 return wgs->wgs_is_initiator && wgs->wgs_time_last_data_sent == 0 && 2367 (time_uptime - wgs->wgs_time_established) >= 2368 (wg_reject_after_time - wg_keepalive_timeout - wg_rekey_timeout); 2369 } 2370 2371 static void 2372 wg_schedule_peer_task(struct wg_peer *wgp, unsigned int task) 2373 { 2374 2375 mutex_enter(wgp->wgp_intr_lock); 2376 WG_DLOG("tasks=%d, task=%d\n", wgp->wgp_tasks, task); 2377 if (wgp->wgp_tasks == 0) 2378 /* 2379 * XXX If the current CPU is already loaded -- e.g., if 2380 * there's already a bunch of handshakes queued up -- 2381 * consider tossing this over to another CPU to 2382 * distribute the load. 2383 */ 2384 workqueue_enqueue(wg_wq, &wgp->wgp_work, NULL); 2385 wgp->wgp_tasks |= task; 2386 mutex_exit(wgp->wgp_intr_lock); 2387 } 2388 2389 static void 2390 wg_change_endpoint(struct wg_peer *wgp, const struct sockaddr *new) 2391 { 2392 struct wg_sockaddr *wgsa_prev; 2393 2394 WG_TRACE("Changing endpoint"); 2395 2396 memcpy(wgp->wgp_endpoint0, new, new->sa_len); 2397 wgsa_prev = wgp->wgp_endpoint; 2398 atomic_store_release(&wgp->wgp_endpoint, wgp->wgp_endpoint0); 2399 wgp->wgp_endpoint0 = wgsa_prev; 2400 atomic_store_release(&wgp->wgp_endpoint_available, true); 2401 2402 wg_schedule_peer_task(wgp, WGP_TASK_ENDPOINT_CHANGED); 2403 } 2404 2405 static bool 2406 wg_validate_inner_packet(const char *packet, size_t decrypted_len, int *af) 2407 { 2408 uint16_t packet_len; 2409 const struct ip *ip; 2410 2411 if (__predict_false(decrypted_len < sizeof(*ip))) { 2412 WG_DLOG("decrypted_len=%zu < %zu\n", decrypted_len, 2413 sizeof(*ip)); 2414 return false; 2415 } 2416 2417 ip = (const struct ip *)packet; 2418 if (ip->ip_v == 4) 2419 *af = AF_INET; 2420 else if (ip->ip_v == 6) 2421 *af = AF_INET6; 2422 else { 2423 WG_DLOG("ip_v=%d\n", ip->ip_v); 2424 return false; 2425 } 2426 2427 WG_DLOG("af=%d\n", *af); 2428 2429 switch (*af) { 2430 #ifdef INET 2431 case AF_INET: 2432 packet_len = ntohs(ip->ip_len); 2433 break; 2434 #endif 2435 #ifdef INET6 2436 case AF_INET6: { 2437 const struct ip6_hdr *ip6; 2438 2439 if (__predict_false(decrypted_len < sizeof(*ip6))) { 2440 WG_DLOG("decrypted_len=%zu < %zu\n", decrypted_len, 2441 sizeof(*ip6)); 2442 return false; 2443 } 2444 2445 ip6 = (const struct ip6_hdr *)packet; 2446 packet_len = sizeof(*ip6) + ntohs(ip6->ip6_plen); 2447 break; 2448 } 2449 #endif 2450 default: 2451 return false; 2452 } 2453 2454 if (packet_len > decrypted_len) { 2455 WG_DLOG("packet_len %u > decrypted_len %zu\n", packet_len, 2456 decrypted_len); 2457 return false; 2458 } 2459 2460 return true; 2461 } 2462 2463 static bool 2464 wg_validate_route(struct wg_softc *wg, struct wg_peer *wgp_expected, 2465 int af, char *packet) 2466 { 2467 struct sockaddr_storage ss; 2468 struct sockaddr *sa; 2469 struct psref psref; 2470 struct wg_peer *wgp; 2471 bool ok; 2472 2473 /* 2474 * II CRYPTOKEY ROUTING 2475 * "it will only accept it if its source IP resolves in the 2476 * table to the public key used in the secure session for 2477 * decrypting it." 2478 */ 2479 2480 if (af == AF_INET) { 2481 const struct ip *ip = (const struct ip *)packet; 2482 struct sockaddr_in *sin = (struct sockaddr_in *)&ss; 2483 sockaddr_in_init(sin, &ip->ip_src, 0); 2484 sa = sintosa(sin); 2485 #ifdef INET6 2486 } else { 2487 const struct ip6_hdr *ip6 = (const struct ip6_hdr *)packet; 2488 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&ss; 2489 sockaddr_in6_init(sin6, &ip6->ip6_src, 0, 0, 0); 2490 sa = sin6tosa(sin6); 2491 #endif 2492 } 2493 2494 wgp = wg_pick_peer_by_sa(wg, sa, &psref); 2495 ok = (wgp == wgp_expected); 2496 if (wgp != NULL) 2497 wg_put_peer(wgp, &psref); 2498 2499 return ok; 2500 } 2501 2502 static void 2503 wg_session_dtor_timer(void *arg) 2504 { 2505 struct wg_peer *wgp = arg; 2506 2507 WG_TRACE("enter"); 2508 2509 wg_schedule_peer_task(wgp, WGP_TASK_DESTROY_PREV_SESSION); 2510 } 2511 2512 static void 2513 wg_schedule_session_dtor_timer(struct wg_peer *wgp) 2514 { 2515 2516 /* 1 second grace period */ 2517 callout_schedule(&wgp->wgp_session_dtor_timer, hz); 2518 } 2519 2520 static bool 2521 sockaddr_port_match(const struct sockaddr *sa1, const struct sockaddr *sa2) 2522 { 2523 if (sa1->sa_family != sa2->sa_family) 2524 return false; 2525 2526 switch (sa1->sa_family) { 2527 #ifdef INET 2528 case AF_INET: 2529 return satocsin(sa1)->sin_port == satocsin(sa2)->sin_port; 2530 #endif 2531 #ifdef INET6 2532 case AF_INET6: 2533 return satocsin6(sa1)->sin6_port == satocsin6(sa2)->sin6_port; 2534 #endif 2535 default: 2536 return false; 2537 } 2538 } 2539 2540 static void 2541 wg_update_endpoint_if_necessary(struct wg_peer *wgp, 2542 const struct sockaddr *src) 2543 { 2544 struct wg_sockaddr *wgsa; 2545 struct psref psref; 2546 2547 wgsa = wg_get_endpoint_sa(wgp, &psref); 2548 2549 #ifdef WG_DEBUG_LOG 2550 char oldaddr[128], newaddr[128]; 2551 sockaddr_format(wgsatosa(wgsa), oldaddr, sizeof(oldaddr)); 2552 sockaddr_format(src, newaddr, sizeof(newaddr)); 2553 WG_DLOG("old=%s, new=%s\n", oldaddr, newaddr); 2554 #endif 2555 2556 /* 2557 * III: "Since the packet has authenticated correctly, the source IP of 2558 * the outer UDP/IP packet is used to update the endpoint for peer..." 2559 */ 2560 if (__predict_false(sockaddr_cmp(src, wgsatosa(wgsa)) != 0 || 2561 !sockaddr_port_match(src, wgsatosa(wgsa)))) { 2562 /* XXX We can't change the endpoint twice in a short period */ 2563 if (atomic_swap_uint(&wgp->wgp_endpoint_changing, 1) == 0) { 2564 wg_change_endpoint(wgp, src); 2565 } 2566 } 2567 2568 wg_put_sa(wgp, wgsa, &psref); 2569 } 2570 2571 static void __noinline 2572 wg_handle_msg_data(struct wg_softc *wg, struct mbuf *m, 2573 const struct sockaddr *src) 2574 { 2575 struct wg_msg_data *wgmd; 2576 char *encrypted_buf = NULL, *decrypted_buf; 2577 size_t encrypted_len, decrypted_len; 2578 struct wg_session *wgs; 2579 struct wg_peer *wgp; 2580 int state; 2581 size_t mlen; 2582 struct psref psref; 2583 int error, af; 2584 bool success, free_encrypted_buf = false, ok; 2585 struct mbuf *n; 2586 2587 KASSERT(m->m_len >= sizeof(struct wg_msg_data)); 2588 wgmd = mtod(m, struct wg_msg_data *); 2589 2590 KASSERT(wgmd->wgmd_type == htole32(WG_MSG_TYPE_DATA)); 2591 WG_TRACE("data"); 2592 2593 /* Find the putative session, or drop. */ 2594 wgs = wg_lookup_session_by_index(wg, wgmd->wgmd_receiver, &psref); 2595 if (wgs == NULL) { 2596 WG_TRACE("No session found"); 2597 m_freem(m); 2598 return; 2599 } 2600 2601 /* 2602 * We are only ready to handle data when in INIT_PASSIVE, 2603 * ESTABLISHED, or DESTROYING. All transitions out of that 2604 * state dissociate the session index and drain psrefs. 2605 */ 2606 state = atomic_load_relaxed(&wgs->wgs_state); 2607 switch (state) { 2608 case WGS_STATE_UNKNOWN: 2609 panic("wg session %p in unknown state has session index %u", 2610 wgs, wgmd->wgmd_receiver); 2611 case WGS_STATE_INIT_ACTIVE: 2612 WG_TRACE("not yet ready for data"); 2613 goto out; 2614 case WGS_STATE_INIT_PASSIVE: 2615 case WGS_STATE_ESTABLISHED: 2616 case WGS_STATE_DESTROYING: 2617 break; 2618 } 2619 2620 /* 2621 * Get the peer, for rate-limited logs (XXX MPSAFE, dtrace) and 2622 * to update the endpoint if authentication succeeds. 2623 */ 2624 wgp = wgs->wgs_peer; 2625 2626 /* 2627 * Reject outrageously wrong sequence numbers before doing any 2628 * crypto work or taking any locks. 2629 */ 2630 error = sliwin_check_fast(&wgs->wgs_recvwin->window, 2631 le64toh(wgmd->wgmd_counter)); 2632 if (error) { 2633 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 2634 "%s: peer %s: out-of-window packet: %"PRIu64"\n", 2635 if_name(&wg->wg_if), wgp->wgp_name, 2636 le64toh(wgmd->wgmd_counter)); 2637 goto out; 2638 } 2639 2640 /* Ensure the payload and authenticator are contiguous. */ 2641 mlen = m_length(m); 2642 encrypted_len = mlen - sizeof(*wgmd); 2643 if (encrypted_len < WG_AUTHTAG_LEN) { 2644 WG_DLOG("Short encrypted_len: %zu\n", encrypted_len); 2645 goto out; 2646 } 2647 success = m_ensure_contig(&m, sizeof(*wgmd) + encrypted_len); 2648 if (success) { 2649 encrypted_buf = mtod(m, char *) + sizeof(*wgmd); 2650 } else { 2651 encrypted_buf = kmem_intr_alloc(encrypted_len, KM_NOSLEEP); 2652 if (encrypted_buf == NULL) { 2653 WG_DLOG("failed to allocate encrypted_buf\n"); 2654 goto out; 2655 } 2656 m_copydata(m, sizeof(*wgmd), encrypted_len, encrypted_buf); 2657 free_encrypted_buf = true; 2658 } 2659 /* m_ensure_contig may change m regardless of its result */ 2660 KASSERT(m->m_len >= sizeof(*wgmd)); 2661 wgmd = mtod(m, struct wg_msg_data *); 2662 2663 #ifdef WG_DEBUG_PACKET 2664 if (wg_debug & WG_DEBUG_FLAGS_PACKET) { 2665 hexdump(printf, "incoming packet", encrypted_buf, 2666 encrypted_len); 2667 } 2668 #endif 2669 /* 2670 * Get a buffer for the plaintext. Add WG_AUTHTAG_LEN to avoid 2671 * a zero-length buffer (XXX). Drop if plaintext is longer 2672 * than MCLBYTES (XXX). 2673 */ 2674 decrypted_len = encrypted_len - WG_AUTHTAG_LEN; 2675 if (decrypted_len > MCLBYTES) { 2676 /* FIXME handle larger data than MCLBYTES */ 2677 WG_DLOG("couldn't handle larger data than MCLBYTES\n"); 2678 goto out; 2679 } 2680 n = wg_get_mbuf(0, decrypted_len + WG_AUTHTAG_LEN); 2681 if (n == NULL) { 2682 WG_DLOG("wg_get_mbuf failed\n"); 2683 goto out; 2684 } 2685 decrypted_buf = mtod(n, char *); 2686 2687 /* Decrypt and verify the packet. */ 2688 WG_DLOG("mlen=%zu, encrypted_len=%zu\n", mlen, encrypted_len); 2689 error = wg_algo_aead_dec(decrypted_buf, 2690 encrypted_len - WG_AUTHTAG_LEN /* can be 0 */, 2691 wgs->wgs_tkey_recv, le64toh(wgmd->wgmd_counter), encrypted_buf, 2692 encrypted_len, NULL, 0); 2693 if (error != 0) { 2694 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 2695 "%s: peer %s: failed to wg_algo_aead_dec\n", 2696 if_name(&wg->wg_if), wgp->wgp_name); 2697 m_freem(n); 2698 goto out; 2699 } 2700 WG_DLOG("outsize=%u\n", (u_int)decrypted_len); 2701 2702 /* Packet is genuine. Reject it if a replay or just too old. */ 2703 mutex_enter(&wgs->wgs_recvwin->lock); 2704 error = sliwin_update(&wgs->wgs_recvwin->window, 2705 le64toh(wgmd->wgmd_counter)); 2706 mutex_exit(&wgs->wgs_recvwin->lock); 2707 if (error) { 2708 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 2709 "%s: peer %s: replay or out-of-window packet: %"PRIu64"\n", 2710 if_name(&wg->wg_if), wgp->wgp_name, 2711 le64toh(wgmd->wgmd_counter)); 2712 m_freem(n); 2713 goto out; 2714 } 2715 2716 #ifdef WG_DEBUG_PACKET 2717 if (wg_debug & WG_DEBUG_FLAGS_PACKET) { 2718 hexdump(aprint_debug, "wgmd", wgmd, sizeof(*wgmd)); 2719 hexdump(aprint_debug, "decrypted_buf", decrypted_buf, 2720 decrypted_len); 2721 } 2722 #endif 2723 /* We're done with m now; free it and chuck the pointers. */ 2724 m_freem(m); 2725 m = NULL; 2726 wgmd = NULL; 2727 2728 /* 2729 * Validate the encapsulated packet header and get the address 2730 * family, or drop. 2731 */ 2732 ok = wg_validate_inner_packet(decrypted_buf, decrypted_len, &af); 2733 if (!ok) { 2734 m_freem(n); 2735 goto out; 2736 } 2737 2738 /* 2739 * The packet is genuine. Update the peer's endpoint if the 2740 * source address changed. 2741 * 2742 * XXX How to prevent DoS by replaying genuine packets from the 2743 * wrong source address? 2744 */ 2745 wg_update_endpoint_if_necessary(wgp, src); 2746 2747 /* Submit it into our network stack if routable. */ 2748 ok = wg_validate_route(wg, wgp, af, decrypted_buf); 2749 if (ok) { 2750 wg->wg_ops->input(&wg->wg_if, n, af); 2751 } else { 2752 char addrstr[INET6_ADDRSTRLEN]; 2753 memset(addrstr, 0, sizeof(addrstr)); 2754 if (af == AF_INET) { 2755 const struct ip *ip = (const struct ip *)decrypted_buf; 2756 IN_PRINT(addrstr, &ip->ip_src); 2757 #ifdef INET6 2758 } else if (af == AF_INET6) { 2759 const struct ip6_hdr *ip6 = 2760 (const struct ip6_hdr *)decrypted_buf; 2761 IN6_PRINT(addrstr, &ip6->ip6_src); 2762 #endif 2763 } 2764 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 2765 "%s: peer %s: invalid source address (%s)\n", 2766 if_name(&wg->wg_if), wgp->wgp_name, addrstr); 2767 m_freem(n); 2768 /* 2769 * The inner address is invalid however the session is valid 2770 * so continue the session processing below. 2771 */ 2772 } 2773 n = NULL; 2774 2775 /* Update the state machine if necessary. */ 2776 if (__predict_false(state == WGS_STATE_INIT_PASSIVE)) { 2777 /* 2778 * We were waiting for the initiator to send their 2779 * first data transport message, and that has happened. 2780 * Schedule a task to establish this session. 2781 */ 2782 wg_schedule_peer_task(wgp, WGP_TASK_ESTABLISH_SESSION); 2783 } else { 2784 if (__predict_false(wg_need_to_send_init_message(wgs))) { 2785 wg_schedule_peer_task(wgp, WGP_TASK_SEND_INIT_MESSAGE); 2786 } 2787 /* 2788 * [W] 6.5 Passive Keepalive 2789 * "If a peer has received a validly-authenticated transport 2790 * data message (section 5.4.6), but does not have any packets 2791 * itself to send back for KEEPALIVE-TIMEOUT seconds, it sends 2792 * a keepalive message." 2793 */ 2794 WG_DLOG("time_uptime=%ju wgs_time_last_data_sent=%ju\n", 2795 (uintmax_t)time_uptime, 2796 (uintmax_t)wgs->wgs_time_last_data_sent); 2797 if ((time_uptime - wgs->wgs_time_last_data_sent) >= 2798 wg_keepalive_timeout) { 2799 WG_TRACE("Schedule sending keepalive message"); 2800 /* 2801 * We can't send a keepalive message here to avoid 2802 * a deadlock; we already hold the solock of a socket 2803 * that is used to send the message. 2804 */ 2805 wg_schedule_peer_task(wgp, 2806 WGP_TASK_SEND_KEEPALIVE_MESSAGE); 2807 } 2808 } 2809 out: 2810 wg_put_session(wgs, &psref); 2811 m_freem(m); 2812 if (free_encrypted_buf) 2813 kmem_intr_free(encrypted_buf, encrypted_len); 2814 } 2815 2816 static void __noinline 2817 wg_handle_msg_cookie(struct wg_softc *wg, const struct wg_msg_cookie *wgmc) 2818 { 2819 struct wg_session *wgs; 2820 struct wg_peer *wgp; 2821 struct psref psref; 2822 int error; 2823 uint8_t key[WG_HASH_LEN]; 2824 uint8_t cookie[WG_COOKIE_LEN]; 2825 2826 WG_TRACE("cookie msg received"); 2827 2828 /* Find the putative session. */ 2829 wgs = wg_lookup_session_by_index(wg, wgmc->wgmc_receiver, &psref); 2830 if (wgs == NULL) { 2831 WG_TRACE("No session found"); 2832 return; 2833 } 2834 2835 /* Lock the peer so we can update the cookie state. */ 2836 wgp = wgs->wgs_peer; 2837 mutex_enter(wgp->wgp_lock); 2838 2839 if (!wgp->wgp_last_sent_mac1_valid) { 2840 WG_TRACE("No valid mac1 sent (or expired)"); 2841 goto out; 2842 } 2843 2844 /* Decrypt the cookie and store it for later handshake retry. */ 2845 wg_algo_mac_cookie(key, sizeof(key), wgp->wgp_pubkey, 2846 sizeof(wgp->wgp_pubkey)); 2847 error = wg_algo_xaead_dec(cookie, sizeof(cookie), key, 2848 wgmc->wgmc_cookie, sizeof(wgmc->wgmc_cookie), 2849 wgp->wgp_last_sent_mac1, sizeof(wgp->wgp_last_sent_mac1), 2850 wgmc->wgmc_salt); 2851 if (error != 0) { 2852 WG_LOG_RATECHECK(&wgp->wgp_ppsratecheck, LOG_DEBUG, 2853 "%s: peer %s: wg_algo_aead_dec for cookie failed: " 2854 "error=%d\n", if_name(&wg->wg_if), wgp->wgp_name, error); 2855 goto out; 2856 } 2857 /* 2858 * [W] 6.6: Interaction with Cookie Reply System 2859 * "it should simply store the decrypted cookie value from the cookie 2860 * reply message, and wait for the expiration of the REKEY-TIMEOUT 2861 * timer for retrying a handshake initiation message." 2862 */ 2863 wgp->wgp_latest_cookie_time = time_uptime; 2864 memcpy(wgp->wgp_latest_cookie, cookie, sizeof(wgp->wgp_latest_cookie)); 2865 out: 2866 mutex_exit(wgp->wgp_lock); 2867 wg_put_session(wgs, &psref); 2868 } 2869 2870 static struct mbuf * 2871 wg_validate_msg_header(struct wg_softc *wg, struct mbuf *m) 2872 { 2873 struct wg_msg wgm; 2874 size_t mbuflen; 2875 size_t msglen; 2876 2877 /* 2878 * Get the mbuf chain length. It is already guaranteed, by 2879 * wg_overudp_cb, to be large enough for a struct wg_msg. 2880 */ 2881 mbuflen = m_length(m); 2882 KASSERT(mbuflen >= sizeof(struct wg_msg)); 2883 2884 /* 2885 * Copy the message header (32-bit message type) out -- we'll 2886 * worry about contiguity and alignment later. 2887 */ 2888 m_copydata(m, 0, sizeof(wgm), &wgm); 2889 switch (le32toh(wgm.wgm_type)) { 2890 case WG_MSG_TYPE_INIT: 2891 msglen = sizeof(struct wg_msg_init); 2892 break; 2893 case WG_MSG_TYPE_RESP: 2894 msglen = sizeof(struct wg_msg_resp); 2895 break; 2896 case WG_MSG_TYPE_COOKIE: 2897 msglen = sizeof(struct wg_msg_cookie); 2898 break; 2899 case WG_MSG_TYPE_DATA: 2900 msglen = sizeof(struct wg_msg_data); 2901 break; 2902 default: 2903 WG_LOG_RATECHECK(&wg->wg_ppsratecheck, LOG_DEBUG, 2904 "%s: Unexpected msg type: %u\n", if_name(&wg->wg_if), 2905 le32toh(wgm.wgm_type)); 2906 goto error; 2907 } 2908 2909 /* Verify the mbuf chain is long enough for this type of message. */ 2910 if (__predict_false(mbuflen < msglen)) { 2911 WG_DLOG("Invalid msg size: mbuflen=%zu type=%u\n", mbuflen, 2912 le32toh(wgm.wgm_type)); 2913 goto error; 2914 } 2915 2916 /* Make the message header contiguous if necessary. */ 2917 if (__predict_false(m->m_len < msglen)) { 2918 m = m_pullup(m, msglen); 2919 if (m == NULL) 2920 return NULL; 2921 } 2922 2923 return m; 2924 2925 error: 2926 m_freem(m); 2927 return NULL; 2928 } 2929 2930 static void 2931 wg_handle_packet(struct wg_softc *wg, struct mbuf *m, 2932 const struct sockaddr *src) 2933 { 2934 struct wg_msg *wgm; 2935 2936 KASSERT(curlwp->l_pflag & LP_BOUND); 2937 2938 m = wg_validate_msg_header(wg, m); 2939 if (__predict_false(m == NULL)) 2940 return; 2941 2942 KASSERT(m->m_len >= sizeof(struct wg_msg)); 2943 wgm = mtod(m, struct wg_msg *); 2944 switch (le32toh(wgm->wgm_type)) { 2945 case WG_MSG_TYPE_INIT: 2946 wg_handle_msg_init(wg, (struct wg_msg_init *)wgm, src); 2947 break; 2948 case WG_MSG_TYPE_RESP: 2949 wg_handle_msg_resp(wg, (struct wg_msg_resp *)wgm, src); 2950 break; 2951 case WG_MSG_TYPE_COOKIE: 2952 wg_handle_msg_cookie(wg, (struct wg_msg_cookie *)wgm); 2953 break; 2954 case WG_MSG_TYPE_DATA: 2955 wg_handle_msg_data(wg, m, src); 2956 /* wg_handle_msg_data frees m for us */ 2957 return; 2958 default: 2959 panic("invalid message type: %d", le32toh(wgm->wgm_type)); 2960 } 2961 2962 m_freem(m); 2963 } 2964 2965 static void 2966 wg_receive_packets(struct wg_softc *wg, const int af) 2967 { 2968 2969 for (;;) { 2970 int error, flags; 2971 struct socket *so; 2972 struct mbuf *m = NULL; 2973 struct uio dummy_uio; 2974 struct mbuf *paddr = NULL; 2975 struct sockaddr *src; 2976 2977 so = wg_get_so_by_af(wg, af); 2978 flags = MSG_DONTWAIT; 2979 dummy_uio.uio_resid = 1000000000; 2980 2981 error = so->so_receive(so, &paddr, &dummy_uio, &m, NULL, 2982 &flags); 2983 if (error || m == NULL) { 2984 //if (error == EWOULDBLOCK) 2985 return; 2986 } 2987 2988 KASSERT(paddr != NULL); 2989 KASSERT(paddr->m_len >= sizeof(struct sockaddr)); 2990 src = mtod(paddr, struct sockaddr *); 2991 2992 wg_handle_packet(wg, m, src); 2993 } 2994 } 2995 2996 static void 2997 wg_get_peer(struct wg_peer *wgp, struct psref *psref) 2998 { 2999 3000 psref_acquire(psref, &wgp->wgp_psref, wg_psref_class); 3001 } 3002 3003 static void 3004 wg_put_peer(struct wg_peer *wgp, struct psref *psref) 3005 { 3006 3007 psref_release(psref, &wgp->wgp_psref, wg_psref_class); 3008 } 3009 3010 static void 3011 wg_task_send_init_message(struct wg_softc *wg, struct wg_peer *wgp) 3012 { 3013 struct wg_session *wgs; 3014 3015 WG_TRACE("WGP_TASK_SEND_INIT_MESSAGE"); 3016 3017 KASSERT(mutex_owned(wgp->wgp_lock)); 3018 3019 if (!atomic_load_acquire(&wgp->wgp_endpoint_available)) { 3020 WGLOG(LOG_DEBUG, "%s: No endpoint available\n", 3021 if_name(&wg->wg_if)); 3022 /* XXX should do something? */ 3023 return; 3024 } 3025 3026 wgs = wgp->wgp_session_stable; 3027 if (wgs->wgs_state == WGS_STATE_UNKNOWN) { 3028 /* XXX What if the unstable session is already INIT_ACTIVE? */ 3029 wg_send_handshake_msg_init(wg, wgp); 3030 } else { 3031 /* rekey */ 3032 wgs = wgp->wgp_session_unstable; 3033 if (wgs->wgs_state != WGS_STATE_INIT_ACTIVE) 3034 wg_send_handshake_msg_init(wg, wgp); 3035 } 3036 } 3037 3038 static void 3039 wg_task_retry_handshake(struct wg_softc *wg, struct wg_peer *wgp) 3040 { 3041 struct wg_session *wgs; 3042 3043 WG_TRACE("WGP_TASK_RETRY_HANDSHAKE"); 3044 3045 KASSERT(mutex_owned(wgp->wgp_lock)); 3046 KASSERT(wgp->wgp_handshake_start_time != 0); 3047 3048 wgs = wgp->wgp_session_unstable; 3049 if (wgs->wgs_state != WGS_STATE_INIT_ACTIVE) 3050 return; 3051 3052 /* 3053 * XXX no real need to assign a new index here, but we do need 3054 * to transition to UNKNOWN temporarily 3055 */ 3056 wg_put_session_index(wg, wgs); 3057 3058 /* [W] 6.4 Handshake Initiation Retransmission */ 3059 if ((time_uptime - wgp->wgp_handshake_start_time) > 3060 wg_rekey_attempt_time) { 3061 /* Give up handshaking */ 3062 wgp->wgp_handshake_start_time = 0; 3063 WG_TRACE("give up"); 3064 3065 /* 3066 * If a new data packet comes, handshaking will be retried 3067 * and a new session would be established at that time, 3068 * however we don't want to send pending packets then. 3069 */ 3070 wg_purge_pending_packets(wgp); 3071 return; 3072 } 3073 3074 wg_task_send_init_message(wg, wgp); 3075 } 3076 3077 static void 3078 wg_task_establish_session(struct wg_softc *wg, struct wg_peer *wgp) 3079 { 3080 struct wg_session *wgs, *wgs_prev; 3081 struct mbuf *m; 3082 3083 KASSERT(mutex_owned(wgp->wgp_lock)); 3084 3085 wgs = wgp->wgp_session_unstable; 3086 if (wgs->wgs_state != WGS_STATE_INIT_PASSIVE) 3087 /* XXX Can this happen? */ 3088 return; 3089 3090 wgs->wgs_state = WGS_STATE_ESTABLISHED; 3091 wgs->wgs_time_established = time_uptime; 3092 wgs->wgs_time_last_data_sent = 0; 3093 wgs->wgs_is_initiator = false; 3094 WG_TRACE("WGS_STATE_ESTABLISHED"); 3095 3096 wg_swap_sessions(wgp); 3097 KASSERT(wgs == wgp->wgp_session_stable); 3098 wgs_prev = wgp->wgp_session_unstable; 3099 getnanotime(&wgp->wgp_last_handshake_time); 3100 wgp->wgp_handshake_start_time = 0; 3101 wgp->wgp_last_sent_mac1_valid = false; 3102 wgp->wgp_last_sent_cookie_valid = false; 3103 3104 /* If we had a data packet queued up, send it. */ 3105 if ((m = atomic_swap_ptr(&wgp->wgp_pending, NULL)) != NULL) { 3106 kpreempt_disable(); 3107 const uint32_t h = curcpu()->ci_index; // pktq_rps_hash(m) 3108 M_SETCTX(m, wgp); 3109 if (__predict_false(!pktq_enqueue(wg_pktq, m, h))) { 3110 WGLOG(LOG_ERR, "%s: pktq full, dropping\n", 3111 if_name(&wg->wg_if)); 3112 m_freem(m); 3113 } 3114 kpreempt_enable(); 3115 } 3116 3117 if (wgs_prev->wgs_state == WGS_STATE_ESTABLISHED) { 3118 /* Wait for wg_get_stable_session to drain. */ 3119 pserialize_perform(wgp->wgp_psz); 3120 3121 /* Transition ESTABLISHED->DESTROYING. */ 3122 wgs_prev->wgs_state = WGS_STATE_DESTROYING; 3123 3124 /* We can't destroy the old session immediately */ 3125 wg_schedule_session_dtor_timer(wgp); 3126 } else { 3127 KASSERTMSG(wgs_prev->wgs_state == WGS_STATE_UNKNOWN, 3128 "state=%d", wgs_prev->wgs_state); 3129 wg_clear_states(wgs_prev); 3130 wgs_prev->wgs_state = WGS_STATE_UNKNOWN; 3131 } 3132 } 3133 3134 static void 3135 wg_task_endpoint_changed(struct wg_softc *wg, struct wg_peer *wgp) 3136 { 3137 3138 WG_TRACE("WGP_TASK_ENDPOINT_CHANGED"); 3139 3140 KASSERT(mutex_owned(wgp->wgp_lock)); 3141 3142 if (atomic_load_relaxed(&wgp->wgp_endpoint_changing)) { 3143 pserialize_perform(wgp->wgp_psz); 3144 mutex_exit(wgp->wgp_lock); 3145 psref_target_destroy(&wgp->wgp_endpoint0->wgsa_psref, 3146 wg_psref_class); 3147 psref_target_init(&wgp->wgp_endpoint0->wgsa_psref, 3148 wg_psref_class); 3149 mutex_enter(wgp->wgp_lock); 3150 atomic_store_release(&wgp->wgp_endpoint_changing, 0); 3151 } 3152 } 3153 3154 static void 3155 wg_task_send_keepalive_message(struct wg_softc *wg, struct wg_peer *wgp) 3156 { 3157 struct wg_session *wgs; 3158 3159 WG_TRACE("WGP_TASK_SEND_KEEPALIVE_MESSAGE"); 3160 3161 KASSERT(mutex_owned(wgp->wgp_lock)); 3162 3163 wgs = wgp->wgp_session_stable; 3164 if (wgs->wgs_state != WGS_STATE_ESTABLISHED) 3165 return; 3166 3167 wg_send_keepalive_msg(wgp, wgs); 3168 } 3169 3170 static void 3171 wg_task_destroy_prev_session(struct wg_softc *wg, struct wg_peer *wgp) 3172 { 3173 struct wg_session *wgs; 3174 3175 WG_TRACE("WGP_TASK_DESTROY_PREV_SESSION"); 3176 3177 KASSERT(mutex_owned(wgp->wgp_lock)); 3178 3179 wgs = wgp->wgp_session_unstable; 3180 if (wgs->wgs_state == WGS_STATE_DESTROYING) { 3181 wg_put_session_index(wg, wgs); 3182 } 3183 } 3184 3185 static void 3186 wg_peer_work(struct work *wk, void *cookie) 3187 { 3188 struct wg_peer *wgp = container_of(wk, struct wg_peer, wgp_work); 3189 struct wg_softc *wg = wgp->wgp_sc; 3190 unsigned int tasks; 3191 3192 mutex_enter(wgp->wgp_intr_lock); 3193 while ((tasks = wgp->wgp_tasks) != 0) { 3194 wgp->wgp_tasks = 0; 3195 mutex_exit(wgp->wgp_intr_lock); 3196 3197 mutex_enter(wgp->wgp_lock); 3198 if (ISSET(tasks, WGP_TASK_SEND_INIT_MESSAGE)) 3199 wg_task_send_init_message(wg, wgp); 3200 if (ISSET(tasks, WGP_TASK_RETRY_HANDSHAKE)) 3201 wg_task_retry_handshake(wg, wgp); 3202 if (ISSET(tasks, WGP_TASK_ESTABLISH_SESSION)) 3203 wg_task_establish_session(wg, wgp); 3204 if (ISSET(tasks, WGP_TASK_ENDPOINT_CHANGED)) 3205 wg_task_endpoint_changed(wg, wgp); 3206 if (ISSET(tasks, WGP_TASK_SEND_KEEPALIVE_MESSAGE)) 3207 wg_task_send_keepalive_message(wg, wgp); 3208 if (ISSET(tasks, WGP_TASK_DESTROY_PREV_SESSION)) 3209 wg_task_destroy_prev_session(wg, wgp); 3210 mutex_exit(wgp->wgp_lock); 3211 3212 mutex_enter(wgp->wgp_intr_lock); 3213 } 3214 mutex_exit(wgp->wgp_intr_lock); 3215 } 3216 3217 static void 3218 wg_job(struct threadpool_job *job) 3219 { 3220 struct wg_softc *wg = container_of(job, struct wg_softc, wg_job); 3221 int bound, upcalls; 3222 3223 mutex_enter(wg->wg_intr_lock); 3224 while ((upcalls = wg->wg_upcalls) != 0) { 3225 wg->wg_upcalls = 0; 3226 mutex_exit(wg->wg_intr_lock); 3227 bound = curlwp_bind(); 3228 if (ISSET(upcalls, WG_UPCALL_INET)) 3229 wg_receive_packets(wg, AF_INET); 3230 if (ISSET(upcalls, WG_UPCALL_INET6)) 3231 wg_receive_packets(wg, AF_INET6); 3232 curlwp_bindx(bound); 3233 mutex_enter(wg->wg_intr_lock); 3234 } 3235 threadpool_job_done(job); 3236 mutex_exit(wg->wg_intr_lock); 3237 } 3238 3239 static int 3240 wg_bind_port(struct wg_softc *wg, const uint16_t port) 3241 { 3242 int error; 3243 uint16_t old_port = wg->wg_listen_port; 3244 3245 if (port != 0 && old_port == port) 3246 return 0; 3247 3248 struct sockaddr_in _sin, *sin = &_sin; 3249 sin->sin_len = sizeof(*sin); 3250 sin->sin_family = AF_INET; 3251 sin->sin_addr.s_addr = INADDR_ANY; 3252 sin->sin_port = htons(port); 3253 3254 error = sobind(wg->wg_so4, sintosa(sin), curlwp); 3255 if (error != 0) 3256 return error; 3257 3258 #ifdef INET6 3259 struct sockaddr_in6 _sin6, *sin6 = &_sin6; 3260 sin6->sin6_len = sizeof(*sin6); 3261 sin6->sin6_family = AF_INET6; 3262 sin6->sin6_addr = in6addr_any; 3263 sin6->sin6_port = htons(port); 3264 3265 error = sobind(wg->wg_so6, sin6tosa(sin6), curlwp); 3266 if (error != 0) 3267 return error; 3268 #endif 3269 3270 wg->wg_listen_port = port; 3271 3272 return 0; 3273 } 3274 3275 static void 3276 wg_so_upcall(struct socket *so, void *cookie, int events, int waitflag) 3277 { 3278 struct wg_softc *wg = cookie; 3279 int reason; 3280 3281 reason = (so->so_proto->pr_domain->dom_family == AF_INET) ? 3282 WG_UPCALL_INET : 3283 WG_UPCALL_INET6; 3284 3285 mutex_enter(wg->wg_intr_lock); 3286 wg->wg_upcalls |= reason; 3287 threadpool_schedule_job(wg->wg_threadpool, &wg->wg_job); 3288 mutex_exit(wg->wg_intr_lock); 3289 } 3290 3291 static int 3292 wg_overudp_cb(struct mbuf **mp, int offset, struct socket *so, 3293 struct sockaddr *src, void *arg) 3294 { 3295 struct wg_softc *wg = arg; 3296 struct wg_msg wgm; 3297 struct mbuf *m = *mp; 3298 3299 WG_TRACE("enter"); 3300 3301 /* Verify the mbuf chain is long enough to have a wg msg header. */ 3302 KASSERT(offset <= m_length(m)); 3303 if (__predict_false(m_length(m) - offset < sizeof(struct wg_msg))) { 3304 /* drop on the floor */ 3305 m_freem(m); 3306 return -1; 3307 } 3308 3309 /* 3310 * Copy the message header (32-bit message type) out -- we'll 3311 * worry about contiguity and alignment later. 3312 */ 3313 m_copydata(m, offset, sizeof(struct wg_msg), &wgm); 3314 WG_DLOG("type=%d\n", le32toh(wgm.wgm_type)); 3315 3316 /* 3317 * Handle DATA packets promptly as they arrive. Other packets 3318 * may require expensive public-key crypto and are not as 3319 * sensitive to latency, so defer them to the worker thread. 3320 */ 3321 switch (le32toh(wgm.wgm_type)) { 3322 case WG_MSG_TYPE_DATA: 3323 /* handle immediately */ 3324 m_adj(m, offset); 3325 if (__predict_false(m->m_len < sizeof(struct wg_msg_data))) { 3326 m = m_pullup(m, sizeof(struct wg_msg_data)); 3327 if (m == NULL) 3328 return -1; 3329 } 3330 wg_handle_msg_data(wg, m, src); 3331 *mp = NULL; 3332 return 1; 3333 case WG_MSG_TYPE_INIT: 3334 case WG_MSG_TYPE_RESP: 3335 case WG_MSG_TYPE_COOKIE: 3336 /* pass through to so_receive in wg_receive_packets */ 3337 return 0; 3338 default: 3339 /* drop on the floor */ 3340 m_freem(m); 3341 return -1; 3342 } 3343 } 3344 3345 static int 3346 wg_socreate(struct wg_softc *wg, int af, struct socket **sop) 3347 { 3348 int error; 3349 struct socket *so; 3350 3351 error = socreate(af, &so, SOCK_DGRAM, 0, curlwp, NULL); 3352 if (error != 0) 3353 return error; 3354 3355 solock(so); 3356 so->so_upcallarg = wg; 3357 so->so_upcall = wg_so_upcall; 3358 so->so_rcv.sb_flags |= SB_UPCALL; 3359 inpcb_register_overudp_cb(sotoinpcb(so), wg_overudp_cb, wg); 3360 sounlock(so); 3361 3362 *sop = so; 3363 3364 return 0; 3365 } 3366 3367 static bool 3368 wg_session_hit_limits(struct wg_session *wgs) 3369 { 3370 3371 /* 3372 * [W] 6.2: Transport Message Limits 3373 * "After REJECT-AFTER-MESSAGES transport data messages or after the 3374 * current secure session is REJECT-AFTER-TIME seconds old, whichever 3375 * comes first, WireGuard will refuse to send any more transport data 3376 * messages using the current secure session, ..." 3377 */ 3378 KASSERT(wgs->wgs_time_established != 0); 3379 if ((time_uptime - wgs->wgs_time_established) > wg_reject_after_time) { 3380 WG_DLOG("The session hits REJECT_AFTER_TIME\n"); 3381 return true; 3382 } else if (wg_session_get_send_counter(wgs) > 3383 wg_reject_after_messages) { 3384 WG_DLOG("The session hits REJECT_AFTER_MESSAGES\n"); 3385 return true; 3386 } 3387 3388 return false; 3389 } 3390 3391 static void 3392 wgintr(void *cookie) 3393 { 3394 struct wg_peer *wgp; 3395 struct wg_session *wgs; 3396 struct mbuf *m; 3397 struct psref psref; 3398 3399 while ((m = pktq_dequeue(wg_pktq)) != NULL) { 3400 wgp = M_GETCTX(m, struct wg_peer *); 3401 if ((wgs = wg_get_stable_session(wgp, &psref)) == NULL) { 3402 WG_TRACE("no stable session"); 3403 wg_schedule_peer_task(wgp, WGP_TASK_SEND_INIT_MESSAGE); 3404 goto next0; 3405 } 3406 if (__predict_false(wg_session_hit_limits(wgs))) { 3407 WG_TRACE("stable session hit limits"); 3408 wg_schedule_peer_task(wgp, WGP_TASK_SEND_INIT_MESSAGE); 3409 goto next1; 3410 } 3411 wg_send_data_msg(wgp, wgs, m); 3412 m = NULL; /* consumed */ 3413 next1: wg_put_session(wgs, &psref); 3414 next0: m_freem(m); 3415 /* XXX Yield to avoid userland starvation? */ 3416 } 3417 } 3418 3419 static void 3420 wg_rekey_timer(void *arg) 3421 { 3422 struct wg_peer *wgp = arg; 3423 3424 wg_schedule_peer_task(wgp, WGP_TASK_SEND_INIT_MESSAGE); 3425 } 3426 3427 static void 3428 wg_purge_pending_packets(struct wg_peer *wgp) 3429 { 3430 struct mbuf *m; 3431 3432 m = atomic_swap_ptr(&wgp->wgp_pending, NULL); 3433 m_freem(m); 3434 pktq_barrier(wg_pktq); 3435 } 3436 3437 static void 3438 wg_handshake_timeout_timer(void *arg) 3439 { 3440 struct wg_peer *wgp = arg; 3441 3442 WG_TRACE("enter"); 3443 3444 wg_schedule_peer_task(wgp, WGP_TASK_RETRY_HANDSHAKE); 3445 } 3446 3447 static struct wg_peer * 3448 wg_alloc_peer(struct wg_softc *wg) 3449 { 3450 struct wg_peer *wgp; 3451 3452 wgp = kmem_zalloc(sizeof(*wgp), KM_SLEEP); 3453 3454 wgp->wgp_sc = wg; 3455 callout_init(&wgp->wgp_rekey_timer, CALLOUT_MPSAFE); 3456 callout_setfunc(&wgp->wgp_rekey_timer, wg_rekey_timer, wgp); 3457 callout_init(&wgp->wgp_handshake_timeout_timer, CALLOUT_MPSAFE); 3458 callout_setfunc(&wgp->wgp_handshake_timeout_timer, 3459 wg_handshake_timeout_timer, wgp); 3460 callout_init(&wgp->wgp_session_dtor_timer, CALLOUT_MPSAFE); 3461 callout_setfunc(&wgp->wgp_session_dtor_timer, 3462 wg_session_dtor_timer, wgp); 3463 PSLIST_ENTRY_INIT(wgp, wgp_peerlist_entry); 3464 wgp->wgp_endpoint_changing = false; 3465 wgp->wgp_endpoint_available = false; 3466 wgp->wgp_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 3467 wgp->wgp_intr_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_SOFTNET); 3468 wgp->wgp_psz = pserialize_create(); 3469 psref_target_init(&wgp->wgp_psref, wg_psref_class); 3470 3471 wgp->wgp_endpoint = kmem_zalloc(sizeof(*wgp->wgp_endpoint), KM_SLEEP); 3472 wgp->wgp_endpoint0 = kmem_zalloc(sizeof(*wgp->wgp_endpoint0), KM_SLEEP); 3473 psref_target_init(&wgp->wgp_endpoint->wgsa_psref, wg_psref_class); 3474 psref_target_init(&wgp->wgp_endpoint0->wgsa_psref, wg_psref_class); 3475 3476 struct wg_session *wgs; 3477 wgp->wgp_session_stable = 3478 kmem_zalloc(sizeof(*wgp->wgp_session_stable), KM_SLEEP); 3479 wgp->wgp_session_unstable = 3480 kmem_zalloc(sizeof(*wgp->wgp_session_unstable), KM_SLEEP); 3481 wgs = wgp->wgp_session_stable; 3482 wgs->wgs_peer = wgp; 3483 wgs->wgs_state = WGS_STATE_UNKNOWN; 3484 psref_target_init(&wgs->wgs_psref, wg_psref_class); 3485 #ifndef __HAVE_ATOMIC64_LOADSTORE 3486 mutex_init(&wgs->wgs_send_counter_lock, MUTEX_DEFAULT, IPL_SOFTNET); 3487 #endif 3488 wgs->wgs_recvwin = kmem_zalloc(sizeof(*wgs->wgs_recvwin), KM_SLEEP); 3489 mutex_init(&wgs->wgs_recvwin->lock, MUTEX_DEFAULT, IPL_SOFTNET); 3490 3491 wgs = wgp->wgp_session_unstable; 3492 wgs->wgs_peer = wgp; 3493 wgs->wgs_state = WGS_STATE_UNKNOWN; 3494 psref_target_init(&wgs->wgs_psref, wg_psref_class); 3495 #ifndef __HAVE_ATOMIC64_LOADSTORE 3496 mutex_init(&wgs->wgs_send_counter_lock, MUTEX_DEFAULT, IPL_SOFTNET); 3497 #endif 3498 wgs->wgs_recvwin = kmem_zalloc(sizeof(*wgs->wgs_recvwin), KM_SLEEP); 3499 mutex_init(&wgs->wgs_recvwin->lock, MUTEX_DEFAULT, IPL_SOFTNET); 3500 3501 return wgp; 3502 } 3503 3504 static void 3505 wg_destroy_peer(struct wg_peer *wgp) 3506 { 3507 struct wg_session *wgs; 3508 struct wg_softc *wg = wgp->wgp_sc; 3509 3510 /* Prevent new packets from this peer on any source address. */ 3511 rw_enter(wg->wg_rwlock, RW_WRITER); 3512 for (int i = 0; i < wgp->wgp_n_allowedips; i++) { 3513 struct wg_allowedip *wga = &wgp->wgp_allowedips[i]; 3514 struct radix_node_head *rnh = wg_rnh(wg, wga->wga_family); 3515 struct radix_node *rn; 3516 3517 KASSERT(rnh != NULL); 3518 rn = rnh->rnh_deladdr(&wga->wga_sa_addr, 3519 &wga->wga_sa_mask, rnh); 3520 if (rn == NULL) { 3521 char addrstr[128]; 3522 sockaddr_format(&wga->wga_sa_addr, addrstr, 3523 sizeof(addrstr)); 3524 WGLOG(LOG_WARNING, "%s: Couldn't delete %s", 3525 if_name(&wg->wg_if), addrstr); 3526 } 3527 } 3528 rw_exit(wg->wg_rwlock); 3529 3530 /* Purge pending packets. */ 3531 wg_purge_pending_packets(wgp); 3532 3533 /* Halt all packet processing and timeouts. */ 3534 callout_halt(&wgp->wgp_rekey_timer, NULL); 3535 callout_halt(&wgp->wgp_handshake_timeout_timer, NULL); 3536 callout_halt(&wgp->wgp_session_dtor_timer, NULL); 3537 3538 /* Wait for any queued work to complete. */ 3539 workqueue_wait(wg_wq, &wgp->wgp_work); 3540 3541 wgs = wgp->wgp_session_unstable; 3542 if (wgs->wgs_state != WGS_STATE_UNKNOWN) { 3543 mutex_enter(wgp->wgp_lock); 3544 wg_destroy_session(wg, wgs); 3545 mutex_exit(wgp->wgp_lock); 3546 } 3547 mutex_destroy(&wgs->wgs_recvwin->lock); 3548 kmem_free(wgs->wgs_recvwin, sizeof(*wgs->wgs_recvwin)); 3549 #ifndef __HAVE_ATOMIC64_LOADSTORE 3550 mutex_destroy(&wgs->wgs_send_counter_lock); 3551 #endif 3552 kmem_free(wgs, sizeof(*wgs)); 3553 3554 wgs = wgp->wgp_session_stable; 3555 if (wgs->wgs_state != WGS_STATE_UNKNOWN) { 3556 mutex_enter(wgp->wgp_lock); 3557 wg_destroy_session(wg, wgs); 3558 mutex_exit(wgp->wgp_lock); 3559 } 3560 mutex_destroy(&wgs->wgs_recvwin->lock); 3561 kmem_free(wgs->wgs_recvwin, sizeof(*wgs->wgs_recvwin)); 3562 #ifndef __HAVE_ATOMIC64_LOADSTORE 3563 mutex_destroy(&wgs->wgs_send_counter_lock); 3564 #endif 3565 kmem_free(wgs, sizeof(*wgs)); 3566 3567 psref_target_destroy(&wgp->wgp_endpoint->wgsa_psref, wg_psref_class); 3568 psref_target_destroy(&wgp->wgp_endpoint0->wgsa_psref, wg_psref_class); 3569 kmem_free(wgp->wgp_endpoint, sizeof(*wgp->wgp_endpoint)); 3570 kmem_free(wgp->wgp_endpoint0, sizeof(*wgp->wgp_endpoint0)); 3571 3572 pserialize_destroy(wgp->wgp_psz); 3573 mutex_obj_free(wgp->wgp_intr_lock); 3574 mutex_obj_free(wgp->wgp_lock); 3575 3576 kmem_free(wgp, sizeof(*wgp)); 3577 } 3578 3579 static void 3580 wg_destroy_all_peers(struct wg_softc *wg) 3581 { 3582 struct wg_peer *wgp, *wgp0 __diagused; 3583 void *garbage_byname, *garbage_bypubkey; 3584 3585 restart: 3586 garbage_byname = garbage_bypubkey = NULL; 3587 mutex_enter(wg->wg_lock); 3588 WG_PEER_WRITER_FOREACH(wgp, wg) { 3589 if (wgp->wgp_name[0]) { 3590 wgp0 = thmap_del(wg->wg_peers_byname, wgp->wgp_name, 3591 strlen(wgp->wgp_name)); 3592 KASSERT(wgp0 == wgp); 3593 garbage_byname = thmap_stage_gc(wg->wg_peers_byname); 3594 } 3595 wgp0 = thmap_del(wg->wg_peers_bypubkey, wgp->wgp_pubkey, 3596 sizeof(wgp->wgp_pubkey)); 3597 KASSERT(wgp0 == wgp); 3598 garbage_bypubkey = thmap_stage_gc(wg->wg_peers_bypubkey); 3599 WG_PEER_WRITER_REMOVE(wgp); 3600 wg->wg_npeers--; 3601 mutex_enter(wgp->wgp_lock); 3602 pserialize_perform(wgp->wgp_psz); 3603 mutex_exit(wgp->wgp_lock); 3604 PSLIST_ENTRY_DESTROY(wgp, wgp_peerlist_entry); 3605 break; 3606 } 3607 mutex_exit(wg->wg_lock); 3608 3609 if (wgp == NULL) 3610 return; 3611 3612 psref_target_destroy(&wgp->wgp_psref, wg_psref_class); 3613 3614 wg_destroy_peer(wgp); 3615 thmap_gc(wg->wg_peers_byname, garbage_byname); 3616 thmap_gc(wg->wg_peers_bypubkey, garbage_bypubkey); 3617 3618 goto restart; 3619 } 3620 3621 static int 3622 wg_destroy_peer_name(struct wg_softc *wg, const char *name) 3623 { 3624 struct wg_peer *wgp, *wgp0 __diagused; 3625 void *garbage_byname, *garbage_bypubkey; 3626 3627 mutex_enter(wg->wg_lock); 3628 wgp = thmap_del(wg->wg_peers_byname, name, strlen(name)); 3629 if (wgp != NULL) { 3630 wgp0 = thmap_del(wg->wg_peers_bypubkey, wgp->wgp_pubkey, 3631 sizeof(wgp->wgp_pubkey)); 3632 KASSERT(wgp0 == wgp); 3633 garbage_byname = thmap_stage_gc(wg->wg_peers_byname); 3634 garbage_bypubkey = thmap_stage_gc(wg->wg_peers_bypubkey); 3635 WG_PEER_WRITER_REMOVE(wgp); 3636 wg->wg_npeers--; 3637 if (wg->wg_npeers == 0) 3638 if_link_state_change(&wg->wg_if, LINK_STATE_DOWN); 3639 mutex_enter(wgp->wgp_lock); 3640 pserialize_perform(wgp->wgp_psz); 3641 mutex_exit(wgp->wgp_lock); 3642 PSLIST_ENTRY_DESTROY(wgp, wgp_peerlist_entry); 3643 } 3644 mutex_exit(wg->wg_lock); 3645 3646 if (wgp == NULL) 3647 return ENOENT; 3648 3649 psref_target_destroy(&wgp->wgp_psref, wg_psref_class); 3650 3651 wg_destroy_peer(wgp); 3652 thmap_gc(wg->wg_peers_byname, garbage_byname); 3653 thmap_gc(wg->wg_peers_bypubkey, garbage_bypubkey); 3654 3655 return 0; 3656 } 3657 3658 static int 3659 wg_if_attach(struct wg_softc *wg) 3660 { 3661 3662 wg->wg_if.if_addrlen = 0; 3663 wg->wg_if.if_mtu = WG_MTU; 3664 wg->wg_if.if_flags = IFF_MULTICAST; 3665 wg->wg_if.if_extflags = IFEF_MPSAFE; 3666 wg->wg_if.if_ioctl = wg_ioctl; 3667 wg->wg_if.if_output = wg_output; 3668 wg->wg_if.if_init = wg_init; 3669 #ifdef ALTQ 3670 wg->wg_if.if_start = wg_start; 3671 #endif 3672 wg->wg_if.if_stop = wg_stop; 3673 wg->wg_if.if_type = IFT_OTHER; 3674 wg->wg_if.if_dlt = DLT_NULL; 3675 wg->wg_if.if_softc = wg; 3676 #ifdef ALTQ 3677 IFQ_SET_READY(&wg->wg_if.if_snd); 3678 #endif 3679 if_initialize(&wg->wg_if); 3680 3681 wg->wg_if.if_link_state = LINK_STATE_DOWN; 3682 if_alloc_sadl(&wg->wg_if); 3683 if_register(&wg->wg_if); 3684 3685 bpf_attach(&wg->wg_if, DLT_NULL, sizeof(uint32_t)); 3686 3687 return 0; 3688 } 3689 3690 static void 3691 wg_if_detach(struct wg_softc *wg) 3692 { 3693 struct ifnet *ifp = &wg->wg_if; 3694 3695 bpf_detach(ifp); 3696 if_detach(ifp); 3697 } 3698 3699 static int 3700 wg_clone_create(struct if_clone *ifc, int unit) 3701 { 3702 struct wg_softc *wg; 3703 int error; 3704 3705 wg_guarantee_initialized(); 3706 3707 error = wg_count_inc(); 3708 if (error) 3709 return error; 3710 3711 wg = kmem_zalloc(sizeof(*wg), KM_SLEEP); 3712 3713 if_initname(&wg->wg_if, ifc->ifc_name, unit); 3714 3715 PSLIST_INIT(&wg->wg_peers); 3716 wg->wg_peers_bypubkey = thmap_create(0, NULL, THMAP_NOCOPY); 3717 wg->wg_peers_byname = thmap_create(0, NULL, THMAP_NOCOPY); 3718 wg->wg_sessions_byindex = thmap_create(0, NULL, THMAP_NOCOPY); 3719 wg->wg_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 3720 wg->wg_intr_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_SOFTNET); 3721 wg->wg_rwlock = rw_obj_alloc(); 3722 threadpool_job_init(&wg->wg_job, wg_job, wg->wg_intr_lock, 3723 "%s", if_name(&wg->wg_if)); 3724 wg->wg_ops = &wg_ops_rumpkernel; 3725 3726 error = threadpool_get(&wg->wg_threadpool, PRI_NONE); 3727 if (error) 3728 goto fail0; 3729 3730 #ifdef INET 3731 error = wg_socreate(wg, AF_INET, &wg->wg_so4); 3732 if (error) 3733 goto fail1; 3734 rn_inithead((void **)&wg->wg_rtable_ipv4, 3735 offsetof(struct sockaddr_in, sin_addr) * NBBY); 3736 #endif 3737 #ifdef INET6 3738 error = wg_socreate(wg, AF_INET6, &wg->wg_so6); 3739 if (error) 3740 goto fail2; 3741 rn_inithead((void **)&wg->wg_rtable_ipv6, 3742 offsetof(struct sockaddr_in6, sin6_addr) * NBBY); 3743 #endif 3744 3745 error = wg_if_attach(wg); 3746 if (error) 3747 goto fail3; 3748 3749 return 0; 3750 3751 fail4: __unused 3752 wg_if_detach(wg); 3753 fail3: wg_destroy_all_peers(wg); 3754 #ifdef INET6 3755 solock(wg->wg_so6); 3756 wg->wg_so6->so_rcv.sb_flags &= ~SB_UPCALL; 3757 sounlock(wg->wg_so6); 3758 #endif 3759 #ifdef INET 3760 solock(wg->wg_so4); 3761 wg->wg_so4->so_rcv.sb_flags &= ~SB_UPCALL; 3762 sounlock(wg->wg_so4); 3763 #endif 3764 mutex_enter(wg->wg_intr_lock); 3765 threadpool_cancel_job(wg->wg_threadpool, &wg->wg_job); 3766 mutex_exit(wg->wg_intr_lock); 3767 #ifdef INET6 3768 if (wg->wg_rtable_ipv6 != NULL) 3769 free(wg->wg_rtable_ipv6, M_RTABLE); 3770 soclose(wg->wg_so6); 3771 fail2: 3772 #endif 3773 #ifdef INET 3774 if (wg->wg_rtable_ipv4 != NULL) 3775 free(wg->wg_rtable_ipv4, M_RTABLE); 3776 soclose(wg->wg_so4); 3777 fail1: 3778 #endif 3779 threadpool_put(wg->wg_threadpool, PRI_NONE); 3780 fail0: threadpool_job_destroy(&wg->wg_job); 3781 rw_obj_free(wg->wg_rwlock); 3782 mutex_obj_free(wg->wg_intr_lock); 3783 mutex_obj_free(wg->wg_lock); 3784 thmap_destroy(wg->wg_sessions_byindex); 3785 thmap_destroy(wg->wg_peers_byname); 3786 thmap_destroy(wg->wg_peers_bypubkey); 3787 PSLIST_DESTROY(&wg->wg_peers); 3788 kmem_free(wg, sizeof(*wg)); 3789 wg_count_dec(); 3790 return error; 3791 } 3792 3793 static int 3794 wg_clone_destroy(struct ifnet *ifp) 3795 { 3796 struct wg_softc *wg = container_of(ifp, struct wg_softc, wg_if); 3797 3798 #ifdef WG_RUMPKERNEL 3799 if (wg_user_mode(wg)) { 3800 rumpuser_wg_destroy(wg->wg_user); 3801 wg->wg_user = NULL; 3802 } 3803 #endif 3804 3805 wg_if_detach(wg); 3806 wg_destroy_all_peers(wg); 3807 #ifdef INET6 3808 solock(wg->wg_so6); 3809 wg->wg_so6->so_rcv.sb_flags &= ~SB_UPCALL; 3810 sounlock(wg->wg_so6); 3811 #endif 3812 #ifdef INET 3813 solock(wg->wg_so4); 3814 wg->wg_so4->so_rcv.sb_flags &= ~SB_UPCALL; 3815 sounlock(wg->wg_so4); 3816 #endif 3817 mutex_enter(wg->wg_intr_lock); 3818 threadpool_cancel_job(wg->wg_threadpool, &wg->wg_job); 3819 mutex_exit(wg->wg_intr_lock); 3820 #ifdef INET6 3821 if (wg->wg_rtable_ipv6 != NULL) 3822 free(wg->wg_rtable_ipv6, M_RTABLE); 3823 soclose(wg->wg_so6); 3824 #endif 3825 #ifdef INET 3826 if (wg->wg_rtable_ipv4 != NULL) 3827 free(wg->wg_rtable_ipv4, M_RTABLE); 3828 soclose(wg->wg_so4); 3829 #endif 3830 threadpool_put(wg->wg_threadpool, PRI_NONE); 3831 threadpool_job_destroy(&wg->wg_job); 3832 rw_obj_free(wg->wg_rwlock); 3833 mutex_obj_free(wg->wg_intr_lock); 3834 mutex_obj_free(wg->wg_lock); 3835 thmap_destroy(wg->wg_sessions_byindex); 3836 thmap_destroy(wg->wg_peers_byname); 3837 thmap_destroy(wg->wg_peers_bypubkey); 3838 PSLIST_DESTROY(&wg->wg_peers); 3839 kmem_free(wg, sizeof(*wg)); 3840 wg_count_dec(); 3841 3842 return 0; 3843 } 3844 3845 static struct wg_peer * 3846 wg_pick_peer_by_sa(struct wg_softc *wg, const struct sockaddr *sa, 3847 struct psref *psref) 3848 { 3849 struct radix_node_head *rnh; 3850 struct radix_node *rn; 3851 struct wg_peer *wgp = NULL; 3852 struct wg_allowedip *wga; 3853 3854 #ifdef WG_DEBUG_LOG 3855 char addrstr[128]; 3856 sockaddr_format(sa, addrstr, sizeof(addrstr)); 3857 WG_DLOG("sa=%s\n", addrstr); 3858 #endif 3859 3860 rw_enter(wg->wg_rwlock, RW_READER); 3861 3862 rnh = wg_rnh(wg, sa->sa_family); 3863 if (rnh == NULL) 3864 goto out; 3865 3866 rn = rnh->rnh_matchaddr(sa, rnh); 3867 if (rn == NULL || (rn->rn_flags & RNF_ROOT) != 0) 3868 goto out; 3869 3870 WG_TRACE("success"); 3871 3872 wga = container_of(rn, struct wg_allowedip, wga_nodes[0]); 3873 wgp = wga->wga_peer; 3874 wg_get_peer(wgp, psref); 3875 3876 out: 3877 rw_exit(wg->wg_rwlock); 3878 return wgp; 3879 } 3880 3881 static void 3882 wg_fill_msg_data(struct wg_softc *wg, struct wg_peer *wgp, 3883 struct wg_session *wgs, struct wg_msg_data *wgmd) 3884 { 3885 3886 memset(wgmd, 0, sizeof(*wgmd)); 3887 wgmd->wgmd_type = htole32(WG_MSG_TYPE_DATA); 3888 wgmd->wgmd_receiver = wgs->wgs_remote_index; 3889 /* [W] 5.4.6: msg.counter := Nm^send */ 3890 /* [W] 5.4.6: Nm^send := Nm^send + 1 */ 3891 wgmd->wgmd_counter = htole64(wg_session_inc_send_counter(wgs)); 3892 WG_DLOG("counter=%"PRIu64"\n", le64toh(wgmd->wgmd_counter)); 3893 } 3894 3895 static int 3896 wg_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 3897 const struct rtentry *rt) 3898 { 3899 struct wg_softc *wg = ifp->if_softc; 3900 struct wg_peer *wgp = NULL; 3901 struct wg_session *wgs = NULL; 3902 struct psref wgp_psref, wgs_psref; 3903 int bound; 3904 int error; 3905 3906 bound = curlwp_bind(); 3907 3908 /* TODO make the nest limit configurable via sysctl */ 3909 error = if_tunnel_check_nesting(ifp, m, 1); 3910 if (error) { 3911 WGLOG(LOG_ERR, 3912 "%s: tunneling loop detected and packet dropped\n", 3913 if_name(&wg->wg_if)); 3914 goto out0; 3915 } 3916 3917 #ifdef ALTQ 3918 bool altq = atomic_load_relaxed(&ifp->if_snd.altq_flags) 3919 & ALTQF_ENABLED; 3920 if (altq) 3921 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family); 3922 #endif 3923 3924 bpf_mtap_af(ifp, dst->sa_family, m, BPF_D_OUT); 3925 3926 m->m_flags &= ~(M_BCAST|M_MCAST); 3927 3928 wgp = wg_pick_peer_by_sa(wg, dst, &wgp_psref); 3929 if (wgp == NULL) { 3930 WG_TRACE("peer not found"); 3931 error = EHOSTUNREACH; 3932 goto out0; 3933 } 3934 3935 /* Clear checksum-offload flags. */ 3936 m->m_pkthdr.csum_flags = 0; 3937 m->m_pkthdr.csum_data = 0; 3938 3939 /* Check whether there's an established session. */ 3940 wgs = wg_get_stable_session(wgp, &wgs_psref); 3941 if (wgs == NULL) { 3942 /* 3943 * No established session. If we're the first to try 3944 * sending data, schedule a handshake and queue the 3945 * packet for when the handshake is done; otherwise 3946 * just drop the packet and let the ongoing handshake 3947 * attempt continue. We could queue more data packets 3948 * but it's not clear that's worthwhile. 3949 */ 3950 if (atomic_cas_ptr(&wgp->wgp_pending, NULL, m) == NULL) { 3951 m = NULL; /* consume */ 3952 WG_TRACE("queued first packet; init handshake"); 3953 wg_schedule_peer_task(wgp, WGP_TASK_SEND_INIT_MESSAGE); 3954 } else { 3955 WG_TRACE("first packet already queued, dropping"); 3956 } 3957 goto out1; 3958 } 3959 3960 /* There's an established session. Toss it in the queue. */ 3961 #ifdef ALTQ 3962 if (altq) { 3963 mutex_enter(ifp->if_snd.ifq_lock); 3964 if (ALTQ_IS_ENABLED(&ifp->if_snd)) { 3965 M_SETCTX(m, wgp); 3966 ALTQ_ENQUEUE(&ifp->if_snd, m, error); 3967 m = NULL; /* consume */ 3968 } 3969 mutex_exit(ifp->if_snd.ifq_lock); 3970 if (m == NULL) { 3971 wg_start(ifp); 3972 goto out2; 3973 } 3974 } 3975 #endif 3976 kpreempt_disable(); 3977 const uint32_t h = curcpu()->ci_index; // pktq_rps_hash(m) 3978 M_SETCTX(m, wgp); 3979 if (__predict_false(!pktq_enqueue(wg_pktq, m, h))) { 3980 WGLOG(LOG_ERR, "%s: pktq full, dropping\n", 3981 if_name(&wg->wg_if)); 3982 error = ENOBUFS; 3983 goto out3; 3984 } 3985 m = NULL; /* consumed */ 3986 error = 0; 3987 out3: kpreempt_enable(); 3988 3989 #ifdef ALTQ 3990 out2: 3991 #endif 3992 wg_put_session(wgs, &wgs_psref); 3993 out1: wg_put_peer(wgp, &wgp_psref); 3994 out0: m_freem(m); 3995 curlwp_bindx(bound); 3996 return error; 3997 } 3998 3999 static int 4000 wg_send_udp(struct wg_peer *wgp, struct mbuf *m) 4001 { 4002 struct psref psref; 4003 struct wg_sockaddr *wgsa; 4004 int error; 4005 struct socket *so; 4006 4007 wgsa = wg_get_endpoint_sa(wgp, &psref); 4008 so = wg_get_so_by_peer(wgp, wgsa); 4009 solock(so); 4010 if (wgsatosa(wgsa)->sa_family == AF_INET) { 4011 error = udp_send(so, m, wgsatosa(wgsa), NULL, curlwp); 4012 } else { 4013 #ifdef INET6 4014 error = udp6_output(sotoinpcb(so), m, wgsatosin6(wgsa), 4015 NULL, curlwp); 4016 #else 4017 m_freem(m); 4018 error = EPFNOSUPPORT; 4019 #endif 4020 } 4021 sounlock(so); 4022 wg_put_sa(wgp, wgsa, &psref); 4023 4024 return error; 4025 } 4026 4027 /* Inspired by pppoe_get_mbuf */ 4028 static struct mbuf * 4029 wg_get_mbuf(size_t leading_len, size_t len) 4030 { 4031 struct mbuf *m; 4032 4033 KASSERT(leading_len <= MCLBYTES); 4034 KASSERT(len <= MCLBYTES - leading_len); 4035 4036 m = m_gethdr(M_DONTWAIT, MT_DATA); 4037 if (m == NULL) 4038 return NULL; 4039 if (len + leading_len > MHLEN) { 4040 m_clget(m, M_DONTWAIT); 4041 if ((m->m_flags & M_EXT) == 0) { 4042 m_free(m); 4043 return NULL; 4044 } 4045 } 4046 m->m_data += leading_len; 4047 m->m_pkthdr.len = m->m_len = len; 4048 4049 return m; 4050 } 4051 4052 static int 4053 wg_send_data_msg(struct wg_peer *wgp, struct wg_session *wgs, 4054 struct mbuf *m) 4055 { 4056 struct wg_softc *wg = wgp->wgp_sc; 4057 int error; 4058 size_t inner_len, padded_len, encrypted_len; 4059 char *padded_buf = NULL; 4060 size_t mlen; 4061 struct wg_msg_data *wgmd; 4062 bool free_padded_buf = false; 4063 struct mbuf *n; 4064 size_t leading_len = max_hdr + sizeof(struct udphdr); 4065 4066 mlen = m_length(m); 4067 inner_len = mlen; 4068 padded_len = roundup(mlen, 16); 4069 encrypted_len = padded_len + WG_AUTHTAG_LEN; 4070 WG_DLOG("inner=%zu, padded=%zu, encrypted_len=%zu\n", 4071 inner_len, padded_len, encrypted_len); 4072 if (mlen != 0) { 4073 bool success; 4074 success = m_ensure_contig(&m, padded_len); 4075 if (success) { 4076 padded_buf = mtod(m, char *); 4077 } else { 4078 padded_buf = kmem_intr_alloc(padded_len, KM_NOSLEEP); 4079 if (padded_buf == NULL) { 4080 error = ENOBUFS; 4081 goto end; 4082 } 4083 free_padded_buf = true; 4084 m_copydata(m, 0, mlen, padded_buf); 4085 } 4086 memset(padded_buf + mlen, 0, padded_len - inner_len); 4087 } 4088 4089 n = wg_get_mbuf(leading_len, sizeof(*wgmd) + encrypted_len); 4090 if (n == NULL) { 4091 error = ENOBUFS; 4092 goto end; 4093 } 4094 KASSERT(n->m_len >= sizeof(*wgmd)); 4095 wgmd = mtod(n, struct wg_msg_data *); 4096 wg_fill_msg_data(wg, wgp, wgs, wgmd); 4097 #ifdef WG_DEBUG_PACKET 4098 if (wg_debug & WG_DEBUG_FLAGS_PACKET) { 4099 hexdump(aprint_debug, "wgmd", wgmd, sizeof(*wgmd)); 4100 hexdump(aprint_debug, "padded_buf", padded_buf, 4101 padded_len); 4102 } 4103 #endif 4104 /* [W] 5.4.6: AEAD(Tm^send, Nm^send, P, e) */ 4105 wg_algo_aead_enc((char *)wgmd + sizeof(*wgmd), encrypted_len, 4106 wgs->wgs_tkey_send, le64toh(wgmd->wgmd_counter), 4107 padded_buf, padded_len, 4108 NULL, 0); 4109 #ifdef WG_DEBUG_PACKET 4110 if (wg_debug & WG_DEBUG_FLAGS_PACKET) { 4111 hexdump(aprint_debug, "outgoing packet", 4112 (char *)wgmd + sizeof(*wgmd), encrypted_len); 4113 size_t decrypted_len = encrypted_len - WG_AUTHTAG_LEN; 4114 char *decrypted_buf = kmem_intr_alloc((decrypted_len + 4115 WG_AUTHTAG_LEN/*XXX*/), KM_NOSLEEP); 4116 if (decrypted_buf != NULL) { 4117 error = wg_algo_aead_dec( 4118 1 + decrypted_buf /* force misalignment */, 4119 encrypted_len - WG_AUTHTAG_LEN /* XXX */, 4120 wgs->wgs_tkey_send, le64toh(wgmd->wgmd_counter), 4121 (char *)wgmd + sizeof(*wgmd), encrypted_len, 4122 NULL, 0); 4123 if (error) { 4124 WG_DLOG("wg_algo_aead_dec failed: %d\n", 4125 error); 4126 } 4127 if (!consttime_memequal(1 + decrypted_buf, 4128 (char *)wgmd + sizeof(*wgmd), 4129 decrypted_len)) { 4130 WG_DLOG("wg_algo_aead_dec returned garbage\n"); 4131 } 4132 kmem_intr_free(decrypted_buf, (decrypted_len + 4133 WG_AUTHTAG_LEN/*XXX*/)); 4134 } 4135 } 4136 #endif 4137 4138 error = wg->wg_ops->send_data_msg(wgp, n); 4139 if (error == 0) { 4140 struct ifnet *ifp = &wg->wg_if; 4141 if_statadd(ifp, if_obytes, mlen); 4142 if_statinc(ifp, if_opackets); 4143 if (wgs->wgs_is_initiator && 4144 wgs->wgs_time_last_data_sent == 0) { 4145 /* 4146 * [W] 6.2 Transport Message Limits 4147 * "if a peer is the initiator of a current secure 4148 * session, WireGuard will send a handshake initiation 4149 * message to begin a new secure session if, after 4150 * transmitting a transport data message, the current 4151 * secure session is REKEY-AFTER-TIME seconds old," 4152 */ 4153 wg_schedule_rekey_timer(wgp); 4154 } 4155 wgs->wgs_time_last_data_sent = time_uptime; 4156 if (wg_session_get_send_counter(wgs) >= 4157 wg_rekey_after_messages) { 4158 /* 4159 * [W] 6.2 Transport Message Limits 4160 * "WireGuard will try to create a new session, by 4161 * sending a handshake initiation message (section 4162 * 5.4.2), after it has sent REKEY-AFTER-MESSAGES 4163 * transport data messages..." 4164 */ 4165 wg_schedule_peer_task(wgp, WGP_TASK_SEND_INIT_MESSAGE); 4166 } 4167 } 4168 end: 4169 m_freem(m); 4170 if (free_padded_buf) 4171 kmem_intr_free(padded_buf, padded_len); 4172 return error; 4173 } 4174 4175 static void 4176 wg_input(struct ifnet *ifp, struct mbuf *m, const int af) 4177 { 4178 pktqueue_t *pktq; 4179 size_t pktlen; 4180 4181 KASSERT(af == AF_INET || af == AF_INET6); 4182 4183 WG_TRACE(""); 4184 4185 m_set_rcvif(m, ifp); 4186 pktlen = m->m_pkthdr.len; 4187 4188 bpf_mtap_af(ifp, af, m, BPF_D_IN); 4189 4190 switch (af) { 4191 case AF_INET: 4192 pktq = ip_pktq; 4193 break; 4194 #ifdef INET6 4195 case AF_INET6: 4196 pktq = ip6_pktq; 4197 break; 4198 #endif 4199 default: 4200 panic("invalid af=%d", af); 4201 } 4202 4203 kpreempt_disable(); 4204 const u_int h = curcpu()->ci_index; 4205 if (__predict_true(pktq_enqueue(pktq, m, h))) { 4206 if_statadd(ifp, if_ibytes, pktlen); 4207 if_statinc(ifp, if_ipackets); 4208 } else { 4209 m_freem(m); 4210 } 4211 kpreempt_enable(); 4212 } 4213 4214 static void 4215 wg_calc_pubkey(uint8_t pubkey[WG_STATIC_KEY_LEN], 4216 const uint8_t privkey[WG_STATIC_KEY_LEN]) 4217 { 4218 4219 crypto_scalarmult_base(pubkey, privkey); 4220 } 4221 4222 static int 4223 wg_rtable_add_route(struct wg_softc *wg, struct wg_allowedip *wga) 4224 { 4225 struct radix_node_head *rnh; 4226 struct radix_node *rn; 4227 int error = 0; 4228 4229 rw_enter(wg->wg_rwlock, RW_WRITER); 4230 rnh = wg_rnh(wg, wga->wga_family); 4231 KASSERT(rnh != NULL); 4232 rn = rnh->rnh_addaddr(&wga->wga_sa_addr, &wga->wga_sa_mask, rnh, 4233 wga->wga_nodes); 4234 rw_exit(wg->wg_rwlock); 4235 4236 if (rn == NULL) 4237 error = EEXIST; 4238 4239 return error; 4240 } 4241 4242 static int 4243 wg_handle_prop_peer(struct wg_softc *wg, prop_dictionary_t peer, 4244 struct wg_peer **wgpp) 4245 { 4246 int error = 0; 4247 const void *pubkey; 4248 size_t pubkey_len; 4249 const void *psk; 4250 size_t psk_len; 4251 const char *name = NULL; 4252 4253 if (prop_dictionary_get_string(peer, "name", &name)) { 4254 if (strlen(name) > WG_PEER_NAME_MAXLEN) { 4255 error = EINVAL; 4256 goto out; 4257 } 4258 } 4259 4260 if (!prop_dictionary_get_data(peer, "public_key", 4261 &pubkey, &pubkey_len)) { 4262 error = EINVAL; 4263 goto out; 4264 } 4265 #ifdef WG_DEBUG_DUMP 4266 if (wg_debug & WG_DEBUG_FLAGS_DUMP) { 4267 char *hex = gethexdump(pubkey, pubkey_len); 4268 log(LOG_DEBUG, "pubkey=%p, pubkey_len=%zu\n%s\n", 4269 pubkey, pubkey_len, hex); 4270 puthexdump(hex, pubkey, pubkey_len); 4271 } 4272 #endif 4273 4274 struct wg_peer *wgp = wg_alloc_peer(wg); 4275 memcpy(wgp->wgp_pubkey, pubkey, sizeof(wgp->wgp_pubkey)); 4276 if (name != NULL) 4277 strncpy(wgp->wgp_name, name, sizeof(wgp->wgp_name)); 4278 4279 if (prop_dictionary_get_data(peer, "preshared_key", &psk, &psk_len)) { 4280 if (psk_len != sizeof(wgp->wgp_psk)) { 4281 error = EINVAL; 4282 goto out; 4283 } 4284 memcpy(wgp->wgp_psk, psk, sizeof(wgp->wgp_psk)); 4285 } 4286 4287 const void *addr; 4288 size_t addr_len; 4289 struct wg_sockaddr *wgsa = wgp->wgp_endpoint; 4290 4291 if (!prop_dictionary_get_data(peer, "endpoint", &addr, &addr_len)) 4292 goto skip_endpoint; 4293 if (addr_len < sizeof(*wgsatosa(wgsa)) || 4294 addr_len > sizeof(*wgsatoss(wgsa))) { 4295 error = EINVAL; 4296 goto out; 4297 } 4298 memcpy(wgsatoss(wgsa), addr, addr_len); 4299 switch (wgsa_family(wgsa)) { 4300 case AF_INET: 4301 #ifdef INET6 4302 case AF_INET6: 4303 #endif 4304 break; 4305 default: 4306 error = EPFNOSUPPORT; 4307 goto out; 4308 } 4309 if (addr_len != sockaddr_getsize_by_family(wgsa_family(wgsa))) { 4310 error = EINVAL; 4311 goto out; 4312 } 4313 { 4314 char addrstr[128]; 4315 sockaddr_format(wgsatosa(wgsa), addrstr, sizeof(addrstr)); 4316 WG_DLOG("addr=%s\n", addrstr); 4317 } 4318 wgp->wgp_endpoint_available = true; 4319 4320 prop_array_t allowedips; 4321 skip_endpoint: 4322 allowedips = prop_dictionary_get(peer, "allowedips"); 4323 if (allowedips == NULL) 4324 goto skip; 4325 4326 prop_object_iterator_t _it = prop_array_iterator(allowedips); 4327 prop_dictionary_t prop_allowedip; 4328 int j = 0; 4329 while ((prop_allowedip = prop_object_iterator_next(_it)) != NULL) { 4330 struct wg_allowedip *wga = &wgp->wgp_allowedips[j]; 4331 4332 if (!prop_dictionary_get_int(prop_allowedip, "family", 4333 &wga->wga_family)) 4334 continue; 4335 if (!prop_dictionary_get_data(prop_allowedip, "ip", 4336 &addr, &addr_len)) 4337 continue; 4338 if (!prop_dictionary_get_uint8(prop_allowedip, "cidr", 4339 &wga->wga_cidr)) 4340 continue; 4341 4342 switch (wga->wga_family) { 4343 case AF_INET: { 4344 struct sockaddr_in sin; 4345 char addrstr[128]; 4346 struct in_addr mask; 4347 struct sockaddr_in sin_mask; 4348 4349 if (addr_len != sizeof(struct in_addr)) 4350 return EINVAL; 4351 memcpy(&wga->wga_addr4, addr, addr_len); 4352 4353 sockaddr_in_init(&sin, (const struct in_addr *)addr, 4354 0); 4355 sockaddr_copy(&wga->wga_sa_addr, 4356 sizeof(sin), sintosa(&sin)); 4357 4358 sockaddr_format(sintosa(&sin), 4359 addrstr, sizeof(addrstr)); 4360 WG_DLOG("addr=%s/%d\n", addrstr, wga->wga_cidr); 4361 4362 in_len2mask(&mask, wga->wga_cidr); 4363 sockaddr_in_init(&sin_mask, &mask, 0); 4364 sockaddr_copy(&wga->wga_sa_mask, 4365 sizeof(sin_mask), sintosa(&sin_mask)); 4366 4367 break; 4368 } 4369 #ifdef INET6 4370 case AF_INET6: { 4371 struct sockaddr_in6 sin6; 4372 char addrstr[128]; 4373 struct in6_addr mask; 4374 struct sockaddr_in6 sin6_mask; 4375 4376 if (addr_len != sizeof(struct in6_addr)) 4377 return EINVAL; 4378 memcpy(&wga->wga_addr6, addr, addr_len); 4379 4380 sockaddr_in6_init(&sin6, (const struct in6_addr *)addr, 4381 0, 0, 0); 4382 sockaddr_copy(&wga->wga_sa_addr, 4383 sizeof(sin6), sin6tosa(&sin6)); 4384 4385 sockaddr_format(sin6tosa(&sin6), 4386 addrstr, sizeof(addrstr)); 4387 WG_DLOG("addr=%s/%d\n", addrstr, wga->wga_cidr); 4388 4389 in6_prefixlen2mask(&mask, wga->wga_cidr); 4390 sockaddr_in6_init(&sin6_mask, &mask, 0, 0, 0); 4391 sockaddr_copy(&wga->wga_sa_mask, 4392 sizeof(sin6_mask), sin6tosa(&sin6_mask)); 4393 4394 break; 4395 } 4396 #endif 4397 default: 4398 error = EINVAL; 4399 goto out; 4400 } 4401 wga->wga_peer = wgp; 4402 4403 error = wg_rtable_add_route(wg, wga); 4404 if (error != 0) 4405 goto out; 4406 4407 j++; 4408 } 4409 wgp->wgp_n_allowedips = j; 4410 skip: 4411 *wgpp = wgp; 4412 out: 4413 return error; 4414 } 4415 4416 static int 4417 wg_alloc_prop_buf(char **_buf, struct ifdrv *ifd) 4418 { 4419 int error; 4420 char *buf; 4421 4422 WG_DLOG("buf=%p, len=%zu\n", ifd->ifd_data, ifd->ifd_len); 4423 if (ifd->ifd_len >= WG_MAX_PROPLEN) 4424 return E2BIG; 4425 buf = kmem_alloc(ifd->ifd_len + 1, KM_SLEEP); 4426 error = copyin(ifd->ifd_data, buf, ifd->ifd_len); 4427 if (error != 0) 4428 return error; 4429 buf[ifd->ifd_len] = '\0'; 4430 #ifdef WG_DEBUG_DUMP 4431 if (wg_debug & WG_DEBUG_FLAGS_DUMP) { 4432 log(LOG_DEBUG, "%.*s\n", (int)MIN(INT_MAX, ifd->ifd_len), 4433 (const char *)buf); 4434 } 4435 #endif 4436 *_buf = buf; 4437 return 0; 4438 } 4439 4440 static int 4441 wg_ioctl_set_private_key(struct wg_softc *wg, struct ifdrv *ifd) 4442 { 4443 int error; 4444 prop_dictionary_t prop_dict; 4445 char *buf = NULL; 4446 const void *privkey; 4447 size_t privkey_len; 4448 4449 error = wg_alloc_prop_buf(&buf, ifd); 4450 if (error != 0) 4451 return error; 4452 error = EINVAL; 4453 prop_dict = prop_dictionary_internalize(buf); 4454 if (prop_dict == NULL) 4455 goto out; 4456 if (!prop_dictionary_get_data(prop_dict, "private_key", 4457 &privkey, &privkey_len)) 4458 goto out; 4459 #ifdef WG_DEBUG_DUMP 4460 if (wg_debug & WG_DEBUG_FLAGS_DUMP) { 4461 char *hex = gethexdump(privkey, privkey_len); 4462 log(LOG_DEBUG, "privkey=%p, privkey_len=%zu\n%s\n", 4463 privkey, privkey_len, hex); 4464 puthexdump(hex, privkey, privkey_len); 4465 } 4466 #endif 4467 if (privkey_len != WG_STATIC_KEY_LEN) 4468 goto out; 4469 memcpy(wg->wg_privkey, privkey, WG_STATIC_KEY_LEN); 4470 wg_calc_pubkey(wg->wg_pubkey, wg->wg_privkey); 4471 error = 0; 4472 4473 out: 4474 kmem_free(buf, ifd->ifd_len + 1); 4475 return error; 4476 } 4477 4478 static int 4479 wg_ioctl_set_listen_port(struct wg_softc *wg, struct ifdrv *ifd) 4480 { 4481 int error; 4482 prop_dictionary_t prop_dict; 4483 char *buf = NULL; 4484 uint16_t port; 4485 4486 error = wg_alloc_prop_buf(&buf, ifd); 4487 if (error != 0) 4488 return error; 4489 error = EINVAL; 4490 prop_dict = prop_dictionary_internalize(buf); 4491 if (prop_dict == NULL) 4492 goto out; 4493 if (!prop_dictionary_get_uint16(prop_dict, "listen_port", &port)) 4494 goto out; 4495 4496 error = wg->wg_ops->bind_port(wg, (uint16_t)port); 4497 4498 out: 4499 kmem_free(buf, ifd->ifd_len + 1); 4500 return error; 4501 } 4502 4503 static int 4504 wg_ioctl_add_peer(struct wg_softc *wg, struct ifdrv *ifd) 4505 { 4506 int error; 4507 prop_dictionary_t prop_dict; 4508 char *buf = NULL; 4509 struct wg_peer *wgp = NULL, *wgp0 __diagused; 4510 4511 error = wg_alloc_prop_buf(&buf, ifd); 4512 if (error != 0) 4513 return error; 4514 error = EINVAL; 4515 prop_dict = prop_dictionary_internalize(buf); 4516 if (prop_dict == NULL) 4517 goto out; 4518 4519 error = wg_handle_prop_peer(wg, prop_dict, &wgp); 4520 if (error != 0) 4521 goto out; 4522 4523 mutex_enter(wg->wg_lock); 4524 if (thmap_get(wg->wg_peers_bypubkey, wgp->wgp_pubkey, 4525 sizeof(wgp->wgp_pubkey)) != NULL || 4526 (wgp->wgp_name[0] && 4527 thmap_get(wg->wg_peers_byname, wgp->wgp_name, 4528 strlen(wgp->wgp_name)) != NULL)) { 4529 mutex_exit(wg->wg_lock); 4530 wg_destroy_peer(wgp); 4531 error = EEXIST; 4532 goto out; 4533 } 4534 wgp0 = thmap_put(wg->wg_peers_bypubkey, wgp->wgp_pubkey, 4535 sizeof(wgp->wgp_pubkey), wgp); 4536 KASSERT(wgp0 == wgp); 4537 if (wgp->wgp_name[0]) { 4538 wgp0 = thmap_put(wg->wg_peers_byname, wgp->wgp_name, 4539 strlen(wgp->wgp_name), wgp); 4540 KASSERT(wgp0 == wgp); 4541 } 4542 WG_PEER_WRITER_INSERT_HEAD(wgp, wg); 4543 wg->wg_npeers++; 4544 mutex_exit(wg->wg_lock); 4545 4546 if_link_state_change(&wg->wg_if, LINK_STATE_UP); 4547 4548 out: 4549 kmem_free(buf, ifd->ifd_len + 1); 4550 return error; 4551 } 4552 4553 static int 4554 wg_ioctl_delete_peer(struct wg_softc *wg, struct ifdrv *ifd) 4555 { 4556 int error; 4557 prop_dictionary_t prop_dict; 4558 char *buf = NULL; 4559 const char *name; 4560 4561 error = wg_alloc_prop_buf(&buf, ifd); 4562 if (error != 0) 4563 return error; 4564 error = EINVAL; 4565 prop_dict = prop_dictionary_internalize(buf); 4566 if (prop_dict == NULL) 4567 goto out; 4568 4569 if (!prop_dictionary_get_string(prop_dict, "name", &name)) 4570 goto out; 4571 if (strlen(name) > WG_PEER_NAME_MAXLEN) 4572 goto out; 4573 4574 error = wg_destroy_peer_name(wg, name); 4575 out: 4576 kmem_free(buf, ifd->ifd_len + 1); 4577 return error; 4578 } 4579 4580 static bool 4581 wg_is_authorized(struct wg_softc *wg, u_long cmd) 4582 { 4583 int au = cmd == SIOCGDRVSPEC ? 4584 KAUTH_REQ_NETWORK_INTERFACE_WG_GETPRIV : 4585 KAUTH_REQ_NETWORK_INTERFACE_WG_SETPRIV; 4586 return kauth_authorize_network(kauth_cred_get(), 4587 KAUTH_NETWORK_INTERFACE_WG, au, &wg->wg_if, 4588 (void *)cmd, NULL) == 0; 4589 } 4590 4591 static int 4592 wg_ioctl_get(struct wg_softc *wg, struct ifdrv *ifd) 4593 { 4594 int error = ENOMEM; 4595 prop_dictionary_t prop_dict; 4596 prop_array_t peers = NULL; 4597 char *buf; 4598 struct wg_peer *wgp; 4599 int s, i; 4600 4601 prop_dict = prop_dictionary_create(); 4602 if (prop_dict == NULL) 4603 goto error; 4604 4605 if (wg_is_authorized(wg, SIOCGDRVSPEC)) { 4606 if (!prop_dictionary_set_data(prop_dict, "private_key", 4607 wg->wg_privkey, WG_STATIC_KEY_LEN)) 4608 goto error; 4609 } 4610 4611 if (wg->wg_listen_port != 0) { 4612 if (!prop_dictionary_set_uint16(prop_dict, "listen_port", 4613 wg->wg_listen_port)) 4614 goto error; 4615 } 4616 4617 if (wg->wg_npeers == 0) 4618 goto skip_peers; 4619 4620 peers = prop_array_create(); 4621 if (peers == NULL) 4622 goto error; 4623 4624 s = pserialize_read_enter(); 4625 i = 0; 4626 WG_PEER_READER_FOREACH(wgp, wg) { 4627 struct wg_sockaddr *wgsa; 4628 struct psref wgp_psref, wgsa_psref; 4629 prop_dictionary_t prop_peer; 4630 4631 wg_get_peer(wgp, &wgp_psref); 4632 pserialize_read_exit(s); 4633 4634 prop_peer = prop_dictionary_create(); 4635 if (prop_peer == NULL) 4636 goto next; 4637 4638 if (strlen(wgp->wgp_name) > 0) { 4639 if (!prop_dictionary_set_string(prop_peer, "name", 4640 wgp->wgp_name)) 4641 goto next; 4642 } 4643 4644 if (!prop_dictionary_set_data(prop_peer, "public_key", 4645 wgp->wgp_pubkey, sizeof(wgp->wgp_pubkey))) 4646 goto next; 4647 4648 uint8_t psk_zero[WG_PRESHARED_KEY_LEN] = {0}; 4649 if (!consttime_memequal(wgp->wgp_psk, psk_zero, 4650 sizeof(wgp->wgp_psk))) { 4651 if (wg_is_authorized(wg, SIOCGDRVSPEC)) { 4652 if (!prop_dictionary_set_data(prop_peer, 4653 "preshared_key", 4654 wgp->wgp_psk, sizeof(wgp->wgp_psk))) 4655 goto next; 4656 } 4657 } 4658 4659 wgsa = wg_get_endpoint_sa(wgp, &wgsa_psref); 4660 CTASSERT(AF_UNSPEC == 0); 4661 if (wgsa_family(wgsa) != 0 /*AF_UNSPEC*/ && 4662 !prop_dictionary_set_data(prop_peer, "endpoint", 4663 wgsatoss(wgsa), 4664 sockaddr_getsize_by_family(wgsa_family(wgsa)))) { 4665 wg_put_sa(wgp, wgsa, &wgsa_psref); 4666 goto next; 4667 } 4668 wg_put_sa(wgp, wgsa, &wgsa_psref); 4669 4670 const struct timespec *t = &wgp->wgp_last_handshake_time; 4671 4672 if (!prop_dictionary_set_uint64(prop_peer, 4673 "last_handshake_time_sec", (uint64_t)t->tv_sec)) 4674 goto next; 4675 if (!prop_dictionary_set_uint32(prop_peer, 4676 "last_handshake_time_nsec", (uint32_t)t->tv_nsec)) 4677 goto next; 4678 4679 if (wgp->wgp_n_allowedips == 0) 4680 goto skip_allowedips; 4681 4682 prop_array_t allowedips = prop_array_create(); 4683 if (allowedips == NULL) 4684 goto next; 4685 for (int j = 0; j < wgp->wgp_n_allowedips; j++) { 4686 struct wg_allowedip *wga = &wgp->wgp_allowedips[j]; 4687 prop_dictionary_t prop_allowedip; 4688 4689 prop_allowedip = prop_dictionary_create(); 4690 if (prop_allowedip == NULL) 4691 break; 4692 4693 if (!prop_dictionary_set_int(prop_allowedip, "family", 4694 wga->wga_family)) 4695 goto _next; 4696 if (!prop_dictionary_set_uint8(prop_allowedip, "cidr", 4697 wga->wga_cidr)) 4698 goto _next; 4699 4700 switch (wga->wga_family) { 4701 case AF_INET: 4702 if (!prop_dictionary_set_data(prop_allowedip, 4703 "ip", &wga->wga_addr4, 4704 sizeof(wga->wga_addr4))) 4705 goto _next; 4706 break; 4707 #ifdef INET6 4708 case AF_INET6: 4709 if (!prop_dictionary_set_data(prop_allowedip, 4710 "ip", &wga->wga_addr6, 4711 sizeof(wga->wga_addr6))) 4712 goto _next; 4713 break; 4714 #endif 4715 default: 4716 break; 4717 } 4718 prop_array_set(allowedips, j, prop_allowedip); 4719 _next: 4720 prop_object_release(prop_allowedip); 4721 } 4722 prop_dictionary_set(prop_peer, "allowedips", allowedips); 4723 prop_object_release(allowedips); 4724 4725 skip_allowedips: 4726 4727 prop_array_set(peers, i, prop_peer); 4728 next: 4729 if (prop_peer) 4730 prop_object_release(prop_peer); 4731 i++; 4732 4733 s = pserialize_read_enter(); 4734 wg_put_peer(wgp, &wgp_psref); 4735 } 4736 pserialize_read_exit(s); 4737 4738 prop_dictionary_set(prop_dict, "peers", peers); 4739 prop_object_release(peers); 4740 peers = NULL; 4741 4742 skip_peers: 4743 buf = prop_dictionary_externalize(prop_dict); 4744 if (buf == NULL) 4745 goto error; 4746 if (ifd->ifd_len < (strlen(buf) + 1)) { 4747 error = EINVAL; 4748 goto error; 4749 } 4750 error = copyout(buf, ifd->ifd_data, strlen(buf) + 1); 4751 4752 free(buf, 0); 4753 error: 4754 if (peers != NULL) 4755 prop_object_release(peers); 4756 if (prop_dict != NULL) 4757 prop_object_release(prop_dict); 4758 4759 return error; 4760 } 4761 4762 static int 4763 wg_ioctl(struct ifnet *ifp, u_long cmd, void *data) 4764 { 4765 struct wg_softc *wg = ifp->if_softc; 4766 struct ifreq *ifr = data; 4767 struct ifaddr *ifa = data; 4768 struct ifdrv *ifd = data; 4769 int error = 0; 4770 4771 switch (cmd) { 4772 case SIOCINITIFADDR: 4773 if (ifa->ifa_addr->sa_family != AF_LINK && 4774 (ifp->if_flags & (IFF_UP | IFF_RUNNING)) != 4775 (IFF_UP | IFF_RUNNING)) { 4776 ifp->if_flags |= IFF_UP; 4777 error = if_init(ifp); 4778 } 4779 return error; 4780 case SIOCADDMULTI: 4781 case SIOCDELMULTI: 4782 switch (ifr->ifr_addr.sa_family) { 4783 case AF_INET: /* IP supports Multicast */ 4784 break; 4785 #ifdef INET6 4786 case AF_INET6: /* IP6 supports Multicast */ 4787 break; 4788 #endif 4789 default: /* Other protocols doesn't support Multicast */ 4790 error = EAFNOSUPPORT; 4791 break; 4792 } 4793 return error; 4794 case SIOCSDRVSPEC: 4795 if (!wg_is_authorized(wg, cmd)) { 4796 return EPERM; 4797 } 4798 switch (ifd->ifd_cmd) { 4799 case WG_IOCTL_SET_PRIVATE_KEY: 4800 error = wg_ioctl_set_private_key(wg, ifd); 4801 break; 4802 case WG_IOCTL_SET_LISTEN_PORT: 4803 error = wg_ioctl_set_listen_port(wg, ifd); 4804 break; 4805 case WG_IOCTL_ADD_PEER: 4806 error = wg_ioctl_add_peer(wg, ifd); 4807 break; 4808 case WG_IOCTL_DELETE_PEER: 4809 error = wg_ioctl_delete_peer(wg, ifd); 4810 break; 4811 default: 4812 error = EINVAL; 4813 break; 4814 } 4815 return error; 4816 case SIOCGDRVSPEC: 4817 return wg_ioctl_get(wg, ifd); 4818 case SIOCSIFFLAGS: 4819 if ((error = ifioctl_common(ifp, cmd, data)) != 0) 4820 break; 4821 switch (ifp->if_flags & (IFF_UP|IFF_RUNNING)) { 4822 case IFF_RUNNING: 4823 /* 4824 * If interface is marked down and it is running, 4825 * then stop and disable it. 4826 */ 4827 if_stop(ifp, 1); 4828 break; 4829 case IFF_UP: 4830 /* 4831 * If interface is marked up and it is stopped, then 4832 * start it. 4833 */ 4834 error = if_init(ifp); 4835 break; 4836 default: 4837 break; 4838 } 4839 return error; 4840 #ifdef WG_RUMPKERNEL 4841 case SIOCSLINKSTR: 4842 error = wg_ioctl_linkstr(wg, ifd); 4843 if (error == 0) 4844 wg->wg_ops = &wg_ops_rumpuser; 4845 return error; 4846 #endif 4847 default: 4848 break; 4849 } 4850 4851 error = ifioctl_common(ifp, cmd, data); 4852 4853 #ifdef WG_RUMPKERNEL 4854 if (!wg_user_mode(wg)) 4855 return error; 4856 4857 /* Do the same to the corresponding tun device on the host */ 4858 /* 4859 * XXX Actually the command has not been handled yet. It 4860 * will be handled via pr_ioctl form doifioctl later. 4861 */ 4862 switch (cmd) { 4863 case SIOCAIFADDR: 4864 case SIOCDIFADDR: { 4865 struct in_aliasreq _ifra = *(const struct in_aliasreq *)data; 4866 struct in_aliasreq *ifra = &_ifra; 4867 KASSERT(error == ENOTTY); 4868 strncpy(ifra->ifra_name, rumpuser_wg_get_tunname(wg->wg_user), 4869 IFNAMSIZ); 4870 error = rumpuser_wg_ioctl(wg->wg_user, cmd, ifra, AF_INET); 4871 if (error == 0) 4872 error = ENOTTY; 4873 break; 4874 } 4875 #ifdef INET6 4876 case SIOCAIFADDR_IN6: 4877 case SIOCDIFADDR_IN6: { 4878 struct in6_aliasreq _ifra = *(const struct in6_aliasreq *)data; 4879 struct in6_aliasreq *ifra = &_ifra; 4880 KASSERT(error == ENOTTY); 4881 strncpy(ifra->ifra_name, rumpuser_wg_get_tunname(wg->wg_user), 4882 IFNAMSIZ); 4883 error = rumpuser_wg_ioctl(wg->wg_user, cmd, ifra, AF_INET6); 4884 if (error == 0) 4885 error = ENOTTY; 4886 break; 4887 } 4888 #endif 4889 } 4890 #endif /* WG_RUMPKERNEL */ 4891 4892 return error; 4893 } 4894 4895 static int 4896 wg_init(struct ifnet *ifp) 4897 { 4898 4899 ifp->if_flags |= IFF_RUNNING; 4900 4901 /* TODO flush pending packets. */ 4902 return 0; 4903 } 4904 4905 #ifdef ALTQ 4906 static void 4907 wg_start(struct ifnet *ifp) 4908 { 4909 struct mbuf *m; 4910 4911 for (;;) { 4912 IFQ_DEQUEUE(&ifp->if_snd, m); 4913 if (m == NULL) 4914 break; 4915 4916 kpreempt_disable(); 4917 const uint32_t h = curcpu()->ci_index; // pktq_rps_hash(m) 4918 if (__predict_false(!pktq_enqueue(wg_pktq, m, h))) { 4919 WGLOG(LOG_ERR, "%s: pktq full, dropping\n", 4920 if_name(ifp)); 4921 m_freem(m); 4922 } 4923 kpreempt_enable(); 4924 } 4925 } 4926 #endif 4927 4928 static void 4929 wg_stop(struct ifnet *ifp, int disable) 4930 { 4931 4932 KASSERT((ifp->if_flags & IFF_RUNNING) != 0); 4933 ifp->if_flags &= ~IFF_RUNNING; 4934 4935 /* Need to do something? */ 4936 } 4937 4938 #ifdef WG_DEBUG_PARAMS 4939 SYSCTL_SETUP(sysctl_net_wg_setup, "sysctl net.wg setup") 4940 { 4941 const struct sysctlnode *node = NULL; 4942 4943 sysctl_createv(clog, 0, NULL, &node, 4944 CTLFLAG_PERMANENT, 4945 CTLTYPE_NODE, "wg", 4946 SYSCTL_DESCR("wg(4)"), 4947 NULL, 0, NULL, 0, 4948 CTL_NET, CTL_CREATE, CTL_EOL); 4949 sysctl_createv(clog, 0, &node, NULL, 4950 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4951 CTLTYPE_QUAD, "rekey_after_messages", 4952 SYSCTL_DESCR("session liftime by messages"), 4953 NULL, 0, &wg_rekey_after_messages, 0, CTL_CREATE, CTL_EOL); 4954 sysctl_createv(clog, 0, &node, NULL, 4955 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4956 CTLTYPE_INT, "rekey_after_time", 4957 SYSCTL_DESCR("session liftime"), 4958 NULL, 0, &wg_rekey_after_time, 0, CTL_CREATE, CTL_EOL); 4959 sysctl_createv(clog, 0, &node, NULL, 4960 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4961 CTLTYPE_INT, "rekey_timeout", 4962 SYSCTL_DESCR("session handshake retry time"), 4963 NULL, 0, &wg_rekey_timeout, 0, CTL_CREATE, CTL_EOL); 4964 sysctl_createv(clog, 0, &node, NULL, 4965 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4966 CTLTYPE_INT, "rekey_attempt_time", 4967 SYSCTL_DESCR("session handshake timeout"), 4968 NULL, 0, &wg_rekey_attempt_time, 0, CTL_CREATE, CTL_EOL); 4969 sysctl_createv(clog, 0, &node, NULL, 4970 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4971 CTLTYPE_INT, "keepalive_timeout", 4972 SYSCTL_DESCR("keepalive timeout"), 4973 NULL, 0, &wg_keepalive_timeout, 0, CTL_CREATE, CTL_EOL); 4974 sysctl_createv(clog, 0, &node, NULL, 4975 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4976 CTLTYPE_BOOL, "force_underload", 4977 SYSCTL_DESCR("force to detemine under load"), 4978 NULL, 0, &wg_force_underload, 0, CTL_CREATE, CTL_EOL); 4979 sysctl_createv(clog, 0, &node, NULL, 4980 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4981 CTLTYPE_INT, "debug", 4982 SYSCTL_DESCR("set debug flags 1=log 2=trace 4=dump 8=packet"), 4983 NULL, 0, &wg_debug, 0, CTL_CREATE, CTL_EOL); 4984 } 4985 #endif 4986 4987 #ifdef WG_RUMPKERNEL 4988 static bool 4989 wg_user_mode(struct wg_softc *wg) 4990 { 4991 4992 return wg->wg_user != NULL; 4993 } 4994 4995 static int 4996 wg_ioctl_linkstr(struct wg_softc *wg, struct ifdrv *ifd) 4997 { 4998 struct ifnet *ifp = &wg->wg_if; 4999 int error; 5000 5001 if (ifp->if_flags & IFF_UP) 5002 return EBUSY; 5003 5004 if (ifd->ifd_cmd == IFLINKSTR_UNSET) { 5005 /* XXX do nothing */ 5006 return 0; 5007 } else if (ifd->ifd_cmd != 0) { 5008 return EINVAL; 5009 } else if (wg->wg_user != NULL) { 5010 return EBUSY; 5011 } 5012 5013 /* Assume \0 included */ 5014 if (ifd->ifd_len > IFNAMSIZ) { 5015 return E2BIG; 5016 } else if (ifd->ifd_len < 1) { 5017 return EINVAL; 5018 } 5019 5020 char tun_name[IFNAMSIZ]; 5021 error = copyinstr(ifd->ifd_data, tun_name, ifd->ifd_len, NULL); 5022 if (error != 0) 5023 return error; 5024 5025 if (strncmp(tun_name, "tun", 3) != 0) 5026 return EINVAL; 5027 5028 error = rumpuser_wg_create(tun_name, wg, &wg->wg_user); 5029 5030 return error; 5031 } 5032 5033 static int 5034 wg_send_user(struct wg_peer *wgp, struct mbuf *m) 5035 { 5036 int error; 5037 struct psref psref; 5038 struct wg_sockaddr *wgsa; 5039 struct wg_softc *wg = wgp->wgp_sc; 5040 struct iovec iov[1]; 5041 5042 wgsa = wg_get_endpoint_sa(wgp, &psref); 5043 5044 iov[0].iov_base = mtod(m, void *); 5045 iov[0].iov_len = m->m_len; 5046 5047 /* Send messages to a peer via an ordinary socket. */ 5048 error = rumpuser_wg_send_peer(wg->wg_user, wgsatosa(wgsa), iov, 1); 5049 5050 wg_put_sa(wgp, wgsa, &psref); 5051 5052 m_freem(m); 5053 5054 return error; 5055 } 5056 5057 static void 5058 wg_input_user(struct ifnet *ifp, struct mbuf *m, const int af) 5059 { 5060 struct wg_softc *wg = ifp->if_softc; 5061 struct iovec iov[2]; 5062 struct sockaddr_storage ss; 5063 5064 KASSERT(af == AF_INET || af == AF_INET6); 5065 5066 WG_TRACE(""); 5067 5068 if (af == AF_INET) { 5069 struct sockaddr_in *sin = (struct sockaddr_in *)&ss; 5070 struct ip *ip; 5071 5072 KASSERT(m->m_len >= sizeof(struct ip)); 5073 ip = mtod(m, struct ip *); 5074 sockaddr_in_init(sin, &ip->ip_dst, 0); 5075 } else { 5076 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&ss; 5077 struct ip6_hdr *ip6; 5078 5079 KASSERT(m->m_len >= sizeof(struct ip6_hdr)); 5080 ip6 = mtod(m, struct ip6_hdr *); 5081 sockaddr_in6_init(sin6, &ip6->ip6_dst, 0, 0, 0); 5082 } 5083 5084 iov[0].iov_base = &ss; 5085 iov[0].iov_len = ss.ss_len; 5086 iov[1].iov_base = mtod(m, void *); 5087 iov[1].iov_len = m->m_len; 5088 5089 WG_DUMP_BUF(iov[1].iov_base, iov[1].iov_len); 5090 5091 /* Send decrypted packets to users via a tun. */ 5092 rumpuser_wg_send_user(wg->wg_user, iov, 2); 5093 5094 m_freem(m); 5095 } 5096 5097 static int 5098 wg_bind_port_user(struct wg_softc *wg, const uint16_t port) 5099 { 5100 int error; 5101 uint16_t old_port = wg->wg_listen_port; 5102 5103 if (port != 0 && old_port == port) 5104 return 0; 5105 5106 error = rumpuser_wg_sock_bind(wg->wg_user, port); 5107 if (error == 0) 5108 wg->wg_listen_port = port; 5109 return error; 5110 } 5111 5112 /* 5113 * Receive user packets. 5114 */ 5115 void 5116 rumpkern_wg_recv_user(struct wg_softc *wg, struct iovec *iov, size_t iovlen) 5117 { 5118 struct ifnet *ifp = &wg->wg_if; 5119 struct mbuf *m; 5120 const struct sockaddr *dst; 5121 5122 WG_TRACE(""); 5123 5124 dst = iov[0].iov_base; 5125 5126 m = m_gethdr(M_DONTWAIT, MT_DATA); 5127 if (m == NULL) 5128 return; 5129 m->m_len = m->m_pkthdr.len = 0; 5130 m_copyback(m, 0, iov[1].iov_len, iov[1].iov_base); 5131 5132 WG_DLOG("iov_len=%zu\n", iov[1].iov_len); 5133 WG_DUMP_BUF(iov[1].iov_base, iov[1].iov_len); 5134 5135 (void)wg_output(ifp, m, dst, NULL); 5136 } 5137 5138 /* 5139 * Receive packets from a peer. 5140 */ 5141 void 5142 rumpkern_wg_recv_peer(struct wg_softc *wg, struct iovec *iov, size_t iovlen) 5143 { 5144 struct mbuf *m; 5145 const struct sockaddr *src; 5146 int bound; 5147 5148 WG_TRACE(""); 5149 5150 src = iov[0].iov_base; 5151 5152 m = m_gethdr(M_DONTWAIT, MT_DATA); 5153 if (m == NULL) 5154 return; 5155 m->m_len = m->m_pkthdr.len = 0; 5156 m_copyback(m, 0, iov[1].iov_len, iov[1].iov_base); 5157 5158 WG_DLOG("iov_len=%zu\n", iov[1].iov_len); 5159 WG_DUMP_BUF(iov[1].iov_base, iov[1].iov_len); 5160 5161 bound = curlwp_bind(); 5162 wg_handle_packet(wg, m, src); 5163 curlwp_bindx(bound); 5164 } 5165 #endif /* WG_RUMPKERNEL */ 5166 5167 /* 5168 * Module infrastructure 5169 */ 5170 #include "if_module.h" 5171 5172 IF_MODULE(MODULE_CLASS_DRIVER, wg, "sodium,blake2s") 5173
Indexes created Wed Sep 24 05:09:52 GMT 2025