1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2021-2022 Rubicon Communications, LLC (Netgate) 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 */ 28 #include "opt_inet.h" 29 #include "opt_inet6.h" 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/buf_ring.h> 34 #include <sys/epoch.h> 35 #include <sys/file.h> 36 #include <sys/filedesc.h> 37 #include <sys/kernel.h> 38 #include <sys/malloc.h> 39 #include <sys/mbuf.h> 40 #include <sys/module.h> 41 #include <sys/nv.h> 42 #include <sys/priv.h> 43 #include <sys/protosw.h> 44 #include <sys/rmlock.h> 45 #include <sys/sdt.h> 46 #include <sys/smp.h> 47 #include <sys/socket.h> 48 #include <sys/socketvar.h> 49 #include <sys/sockio.h> 50 #include <sys/sysctl.h> 51 #include <sys/time.h> 52 53 #include <machine/atomic.h> 54 55 #include <net/bpf.h> 56 #include <net/if.h> 57 #include <net/if_clone.h> 58 #include <net/if_types.h> 59 #include <net/if_var.h> 60 #include <net/netisr.h> 61 #include <net/route/nhop.h> 62 63 #include <netinet/in.h> 64 #include <netinet/in_fib.h> 65 #include <netinet/ip.h> 66 #include <netinet/ip6.h> 67 #include <netinet/ip_var.h> 68 #include <netinet/udp.h> 69 #include <netinet/udp_var.h> 70 71 #include <netinet6/ip6_var.h> 72 #include <netinet6/in6_fib.h> 73 74 #include <machine/in_cksum.h> 75 76 #include <opencrypto/cryptodev.h> 77 78 #include "if_ovpn.h" 79 80 struct ovpn_kkey_dir { 81 int refcount; 82 uint8_t key[32]; 83 uint8_t keylen; 84 uint8_t nonce[8]; 85 uint8_t noncelen; 86 enum ovpn_key_cipher cipher; 87 crypto_session_t cryptoid; 88 89 struct mtx replay_mtx; 90 /* 91 * Last seen gapless sequence number. New rx seq numbers must be 92 * strictly higher than this. 93 */ 94 uint32_t rx_seq; 95 /* Seen packets, relative to rx_seq. bit(0) will always be 0. */ 96 uint64_t rx_window; 97 }; 98 99 struct ovpn_kkey { 100 struct ovpn_kkey_dir *encrypt; 101 struct ovpn_kkey_dir *decrypt; 102 uint8_t keyid; 103 uint32_t peerid; 104 }; 105 106 struct ovpn_keepalive { 107 uint32_t interval; 108 uint32_t timeout; 109 }; 110 111 struct ovpn_wire_header { 112 uint32_t opcode; /* opcode, key id, peer id */ 113 uint32_t seq; 114 uint8_t auth_tag[16]; 115 }; 116 117 struct ovpn_notification { 118 enum ovpn_notif_type type; 119 uint32_t peerid; 120 }; 121 122 struct ovpn_softc; 123 124 struct ovpn_kpeer { 125 int refcount; 126 uint32_t peerid; 127 128 struct ovpn_softc *sc; 129 struct sockaddr_storage local; 130 struct sockaddr_storage remote; 131 132 struct in_addr vpn4; 133 struct in6_addr vpn6; 134 135 struct ovpn_kkey keys[2]; 136 uint32_t tx_seq; 137 138 struct ovpn_keepalive keepalive; 139 uint32_t *last_active; 140 struct callout ping_send; 141 struct callout ping_rcv; 142 }; 143 144 #define OVPN_MAX_PEERS 128 145 146 struct ovpn_counters { 147 uint64_t lost_ctrl_pkts_in; 148 uint64_t lost_ctrl_pkts_out; 149 uint64_t lost_data_pkts_in; 150 uint64_t lost_data_pkts_out; 151 uint64_t nomem_data_pkts_in; 152 uint64_t nomem_data_pkts_out; 153 uint64_t received_ctrl_pkts; 154 uint64_t received_data_pkts; 155 uint64_t sent_ctrl_pkts; 156 uint64_t sent_data_pkts; 157 158 uint64_t transport_bytes_sent; 159 uint64_t transport_bytes_received; 160 uint64_t tunnel_bytes_sent; 161 uint64_t tunnel_bytes_received; 162 }; 163 #define OVPN_COUNTER_SIZE (sizeof(struct ovpn_counters)/sizeof(uint64_t)) 164 165 struct ovpn_softc { 166 int refcount; 167 struct rmlock lock; 168 struct ifnet *ifp; 169 struct socket *so; 170 int peercount; 171 struct ovpn_kpeer *peers[OVPN_MAX_PEERS]; /* XXX Hard limit for now? */ 172 173 /* Pending packets */ 174 struct buf_ring *rxring; 175 struct buf_ring *notifring; 176 177 counter_u64_t counters[OVPN_COUNTER_SIZE]; 178 179 struct epoch_context epoch_ctx; 180 }; 181 182 static struct ovpn_kpeer *ovpn_find_peer(struct ovpn_softc *, uint32_t); 183 static bool ovpn_udp_input(struct mbuf *, int, struct inpcb *, 184 const struct sockaddr *, void *); 185 static int ovpn_transmit_to_peer(struct ifnet *, struct mbuf *, 186 struct ovpn_kpeer *, struct rm_priotracker *); 187 static int ovpn_encap(struct ovpn_softc *, uint32_t, struct mbuf *); 188 static int ovpn_get_af(struct mbuf *); 189 static void ovpn_free_kkey_dir(struct ovpn_kkey_dir *); 190 static bool ovpn_check_replay(struct ovpn_kkey_dir *, uint32_t); 191 192 #define OVPN_MTU_MIN 576 193 #define OVPN_MTU_MAX (IP_MAXPACKET - sizeof(struct ip) - \ 194 sizeof(struct udphdr) - sizeof(struct ovpn_wire_header)) 195 196 #define OVPN_OP_DATA_V2 0x09 197 #define OVPN_OP_SHIFT 3 198 199 VNET_DEFINE_STATIC(struct if_clone *, ovpn_cloner); 200 #define V_ovpn_cloner VNET(ovpn_cloner) 201 202 #define OVPN_RLOCK_TRACKER struct rm_priotracker _ovpn_lock_tracker; \ 203 struct rm_priotracker *_ovpn_lock_trackerp = &_ovpn_lock_tracker 204 #define OVPN_RLOCK(sc) rm_rlock(&(sc)->lock, _ovpn_lock_trackerp) 205 #define OVPN_RUNLOCK(sc) rm_runlock(&(sc)->lock, _ovpn_lock_trackerp) 206 #define OVPN_WLOCK(sc) rm_wlock(&(sc)->lock) 207 #define OVPN_WUNLOCK(sc) rm_wunlock(&(sc)->lock) 208 #define OVPN_ASSERT(sc) rm_assert(&(sc)->lock, RA_LOCKED) 209 #define OVPN_RASSERT(sc) rm_assert(&(sc)->lock, RA_RLOCKED) 210 #define OVPN_WASSERT(sc) rm_assert(&(sc)->lock, RA_WLOCKED) 211 #define OVPN_UNLOCK_ASSERT(sc) rm_assert(&(sc)->lock, RA_UNLOCKED) 212 213 #define OVPN_COUNTER_ADD(sc, name, val) \ 214 counter_u64_add(sc->counters[offsetof(struct ovpn_counters, name) / \ 215 sizeof(uint64_t)], val) 216 217 #define TO_IN(x) ((struct sockaddr_in *)(x)) 218 #define TO_IN6(x) ((struct sockaddr_in6 *)(x)) 219 220 SDT_PROVIDER_DEFINE(if_ovpn); 221 SDT_PROBE_DEFINE1(if_ovpn, tx, transmit, start, "struct mbuf *"); 222 SDT_PROBE_DEFINE2(if_ovpn, tx, route, ip4, "struct in_addr *", "struct ovpn_kpeer *"); 223 SDT_PROBE_DEFINE2(if_ovpn, tx, route, ip6, "struct in6_addr *", "struct ovpn_kpeer *"); 224 225 static const char ovpnname[] = "ovpn"; 226 static const char ovpngroupname[] = "openvpn"; 227 228 static MALLOC_DEFINE(M_OVPN, ovpnname, "OpenVPN DCO Interface"); 229 230 SYSCTL_DECL(_net_link); 231 static SYSCTL_NODE(_net_link, IFT_OTHER, openvpn, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 232 "OpenVPN DCO Interface"); 233 VNET_DEFINE_STATIC(int, replay_protection) = 0; 234 #define V_replay_protection VNET(replay_protection) 235 SYSCTL_INT(_net_link_openvpn, OID_AUTO, replay_protection, CTLFLAG_VNET | CTLFLAG_RW, 236 &VNET_NAME(replay_protection), 0, "Validate sequence numbers"); 237 238 VNET_DEFINE_STATIC(int, async_crypto); 239 #define V_async_crypto VNET(async_crypto) 240 SYSCTL_INT(_net_link_openvpn, OID_AUTO, async_crypto, 241 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(async_crypto), 0, 242 "Use asynchronous mode to parallelize crypto jobs."); 243 244 VNET_DEFINE_STATIC(int, async_netisr_queue); 245 #define V_async_netisr_queue VNET(async_netisr_queue) 246 SYSCTL_INT(_net_link_openvpn, OID_AUTO, netisr_queue, 247 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(async_netisr_queue), 0, 248 "Use netisr_queue() rather than netisr_dispatch()."); 249 250 static struct ovpn_kpeer * 251 ovpn_find_peer(struct ovpn_softc *sc, uint32_t peerid) 252 { 253 struct ovpn_kpeer *p = NULL; 254 255 OVPN_ASSERT(sc); 256 257 for (int i = 0; i < OVPN_MAX_PEERS; i++) { 258 p = sc->peers[i]; 259 if (p == NULL) 260 continue; 261 262 if (p->peerid == peerid) { 263 MPASS(p->sc == sc); 264 break; 265 } 266 } 267 268 return (p); 269 } 270 271 static struct ovpn_kpeer * 272 ovpn_find_only_peer(struct ovpn_softc *sc) 273 { 274 OVPN_ASSERT(sc); 275 276 for (int i = 0; i < OVPN_MAX_PEERS; i++) { 277 if (sc->peers[i] == NULL) 278 continue; 279 return (sc->peers[i]); 280 } 281 282 MPASS(false); 283 284 return (NULL); 285 } 286 287 static uint16_t 288 ovpn_get_port(struct sockaddr_storage *s) 289 { 290 switch (s->ss_family) { 291 case AF_INET: { 292 struct sockaddr_in *in = (struct sockaddr_in *)s; 293 return (in->sin_port); 294 } 295 case AF_INET6: { 296 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)s; 297 return (in6->sin6_port); 298 } 299 default: 300 panic("Unsupported address family %d", s->ss_family); 301 } 302 } 303 304 static int 305 ovpn_nvlist_to_sockaddr(const nvlist_t *nvl, struct sockaddr_storage *sa) 306 { 307 int af; 308 309 if (! nvlist_exists_number(nvl, "af")) 310 return (EINVAL); 311 if (! nvlist_exists_binary(nvl, "address")) 312 return (EINVAL); 313 if (! nvlist_exists_number(nvl, "port")) 314 return (EINVAL); 315 316 af = nvlist_get_number(nvl, "af"); 317 318 switch (af) { 319 #ifdef INET 320 case AF_INET: { 321 struct sockaddr_in *in = (struct sockaddr_in *)sa; 322 size_t len; 323 const void *addr = nvlist_get_binary(nvl, "address", &len); 324 in->sin_family = af; 325 if (len != sizeof(in->sin_addr)) 326 return (EINVAL); 327 328 memcpy(&in->sin_addr, addr, sizeof(in->sin_addr)); 329 in->sin_port = nvlist_get_number(nvl, "port"); 330 break; 331 } 332 #endif 333 #ifdef INET6 334 case AF_INET6: { 335 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)sa; 336 size_t len; 337 const void *addr = nvlist_get_binary(nvl, "address", &len); 338 in6->sin6_family = af; 339 if (len != sizeof(in6->sin6_addr)) 340 return (EINVAL); 341 342 memcpy(&in6->sin6_addr, addr, sizeof(in6->sin6_addr)); 343 in6->sin6_port = nvlist_get_number(nvl, "port"); 344 break; 345 } 346 #endif 347 default: 348 return (EINVAL); 349 } 350 351 return (0); 352 } 353 354 static bool 355 ovpn_has_peers(struct ovpn_softc *sc) 356 { 357 OVPN_ASSERT(sc); 358 359 return (sc->peercount > 0); 360 } 361 362 static void 363 ovpn_rele_so(struct ovpn_softc *sc, struct ovpn_kpeer *peer) 364 { 365 bool has_peers; 366 367 OVPN_WASSERT(sc); 368 369 if (sc->so == NULL) 370 return; 371 372 has_peers = ovpn_has_peers(sc); 373 374 /* Only remove the tunnel function if we're releasing the socket for 375 * the last peer. */ 376 if (! has_peers) 377 (void)udp_set_kernel_tunneling(sc->so, NULL, NULL, NULL); 378 379 sorele(sc->so); 380 381 if (! has_peers) 382 sc->so = NULL; 383 } 384 385 static void 386 ovpn_notify_del_peer(struct ovpn_softc *sc, struct ovpn_kpeer *peer) 387 { 388 struct ovpn_notification *n; 389 390 OVPN_WASSERT(sc); 391 392 n = malloc(sizeof(*n), M_OVPN, M_NOWAIT); 393 if (n == NULL) 394 return; 395 396 n->peerid = peer->peerid; 397 n->type = OVPN_NOTIF_DEL_PEER; 398 if (buf_ring_enqueue(sc->notifring, n) != 0) { 399 free(n, M_OVPN); 400 } else if (sc->so != NULL) { 401 /* Wake up userspace */ 402 sc->so->so_error = EAGAIN; 403 sorwakeup(sc->so); 404 sowwakeup(sc->so); 405 } 406 } 407 408 static void 409 ovpn_peer_release_ref(struct ovpn_kpeer *peer, bool locked) 410 { 411 struct ovpn_softc *sc; 412 413 atomic_add_int(&peer->refcount, -1); 414 415 if (atomic_load_int(&peer->refcount) > 0) 416 return; 417 418 sc = peer->sc; 419 420 if (! locked) { 421 OVPN_WLOCK(sc); 422 423 /* Might have changed before we acquired the lock. */ 424 if (atomic_load_int(&peer->refcount) > 0) { 425 OVPN_WUNLOCK(sc); 426 return; 427 } 428 } 429 430 /* The peer should have been removed from the list already. */ 431 MPASS(ovpn_find_peer(sc, peer->peerid) == NULL); 432 433 ovpn_notify_del_peer(sc, peer); 434 435 for (int i = 0; i < 2; i++) { 436 ovpn_free_kkey_dir(peer->keys[i].encrypt); 437 ovpn_free_kkey_dir(peer->keys[i].decrypt); 438 } 439 440 ovpn_rele_so(sc, peer); 441 442 callout_stop(&peer->ping_send); 443 callout_stop(&peer->ping_rcv); 444 uma_zfree_pcpu(pcpu_zone_4, peer->last_active); 445 free(peer, M_OVPN); 446 447 if (! locked) 448 OVPN_WUNLOCK(sc); 449 } 450 451 static int 452 ovpn_new_peer(struct ifnet *ifp, const nvlist_t *nvl) 453 { 454 #ifdef INET6 455 struct epoch_tracker et; 456 #endif 457 struct sockaddr_storage remote; 458 struct ovpn_kpeer *peer = NULL; 459 struct file *fp = NULL; 460 struct sockaddr *name = NULL; 461 struct ovpn_softc *sc = ifp->if_softc; 462 struct thread *td = curthread; 463 struct socket *so = NULL; 464 int fd; 465 uint32_t peerid; 466 int ret = 0, i; 467 468 if (nvl == NULL) 469 return (EINVAL); 470 471 if (! nvlist_exists_number(nvl, "peerid")) 472 return (EINVAL); 473 474 if (! nvlist_exists_number(nvl, "fd")) 475 return (EINVAL); 476 477 if (! nvlist_exists_nvlist(nvl, "remote")) 478 return (EINVAL); 479 480 peerid = nvlist_get_number(nvl, "peerid"); 481 482 ret = ovpn_nvlist_to_sockaddr(nvlist_get_nvlist(nvl, "remote"), 483 &remote); 484 if (ret != 0) 485 return (ret); 486 487 fd = nvlist_get_number(nvl, "fd"); 488 489 /* Look up the userspace process and use the fd to find the socket. */ 490 ret = getsock(td, fd, &cap_connect_rights, &fp); 491 if (ret != 0) 492 return (ret); 493 494 so = fp->f_data; 495 496 peer = malloc(sizeof(*peer), M_OVPN, M_WAITOK | M_ZERO); 497 peer->peerid = peerid; 498 peer->sc = sc; 499 peer->tx_seq = 1; 500 peer->refcount = 1; 501 peer->last_active = uma_zalloc_pcpu(pcpu_zone_4, M_WAITOK | M_ZERO); 502 503 if (nvlist_exists_binary(nvl, "vpn_ipv4")) { 504 size_t len; 505 const void *addr = nvlist_get_binary(nvl, "vpn_ipv4", &len); 506 if (len != sizeof(peer->vpn4)) { 507 ret = EINVAL; 508 goto error; 509 } 510 memcpy(&peer->vpn4, addr, len); 511 } 512 513 if (nvlist_exists_binary(nvl, "vpn_ipv6")) { 514 size_t len; 515 const void *addr = nvlist_get_binary(nvl, "vpn_ipv6", &len); 516 if (len != sizeof(peer->vpn6)) { 517 ret = EINVAL; 518 goto error; 519 } 520 memcpy(&peer->vpn6, addr, len); 521 } 522 523 callout_init_rm(&peer->ping_send, &sc->lock, CALLOUT_SHAREDLOCK); 524 callout_init_rm(&peer->ping_rcv, &sc->lock, 0); 525 526 ret = so->so_proto->pr_sockaddr(so, &name); 527 if (ret) 528 goto error; 529 530 if (ovpn_get_port((struct sockaddr_storage *)name) == 0) { 531 ret = EINVAL; 532 goto error; 533 } 534 if (name->sa_family != remote.ss_family) { 535 ret = EINVAL; 536 goto error; 537 } 538 539 memcpy(&peer->local, name, name->sa_len); 540 memcpy(&peer->remote, &remote, sizeof(remote)); 541 free(name, M_SONAME); 542 name = NULL; 543 544 if (peer->local.ss_family == AF_INET6 && 545 IN6_IS_ADDR_V4MAPPED(&TO_IN6(&peer->remote)->sin6_addr)) { 546 /* V4 mapped address, so treat this as v4, not v6. */ 547 in6_sin6_2_sin_in_sock((struct sockaddr *)&peer->local); 548 in6_sin6_2_sin_in_sock((struct sockaddr *)&peer->remote); 549 } 550 551 #ifdef INET6 552 if (peer->local.ss_family == AF_INET6 && 553 IN6_IS_ADDR_UNSPECIFIED(&TO_IN6(&peer->local)->sin6_addr)) { 554 NET_EPOCH_ENTER(et); 555 ret = in6_selectsrc_addr(curthread->td_proc->p_fibnum, 556 &TO_IN6(&peer->remote)->sin6_addr, 557 0, NULL, &TO_IN6(&peer->local)->sin6_addr, NULL); 558 NET_EPOCH_EXIT(et); 559 if (ret != 0) { 560 goto error; 561 } 562 } 563 #endif 564 OVPN_WLOCK(sc); 565 566 /* Disallow peer id re-use. */ 567 if (ovpn_find_peer(sc, peerid) != NULL) { 568 ret = EEXIST; 569 goto error_locked; 570 } 571 572 /* Make sure this is really a UDP socket. */ 573 if (so->so_type != SOCK_DGRAM || so->so_proto->pr_type != SOCK_DGRAM) { 574 ret = EPROTOTYPE; 575 goto error_locked; 576 } 577 578 /* Must be the same socket as for other peers on this interface. */ 579 if (sc->so != NULL && so != sc->so) 580 goto error_locked; 581 582 if (sc->so == NULL) 583 sc->so = so; 584 585 /* Insert the peer into the list. */ 586 for (i = 0; i < OVPN_MAX_PEERS; i++) { 587 if (sc->peers[i] != NULL) 588 continue; 589 590 MPASS(sc->peers[i] == NULL); 591 sc->peers[i] = peer; 592 sc->peercount++; 593 soref(sc->so); 594 break; 595 } 596 if (i == OVPN_MAX_PEERS) { 597 ret = ENOSPC; 598 goto error_locked; 599 } 600 601 ret = udp_set_kernel_tunneling(sc->so, ovpn_udp_input, NULL, sc); 602 if (ret == EBUSY) { 603 /* Fine, another peer already set the input function. */ 604 ret = 0; 605 } 606 if (ret != 0) { 607 sc->peers[i] = NULL; 608 sc->peercount--; 609 goto error_locked; 610 } 611 612 OVPN_WUNLOCK(sc); 613 614 goto done; 615 616 error_locked: 617 OVPN_WUNLOCK(sc); 618 error: 619 free(name, M_SONAME); 620 uma_zfree_pcpu(pcpu_zone_4, peer->last_active); 621 free(peer, M_OVPN); 622 done: 623 if (fp != NULL) 624 fdrop(fp, td); 625 626 return (ret); 627 } 628 629 static int 630 _ovpn_del_peer(struct ovpn_softc *sc, uint32_t peerid) 631 { 632 struct ovpn_kpeer *peer; 633 int i; 634 635 OVPN_WASSERT(sc); 636 637 for (i = 0; i < OVPN_MAX_PEERS; i++) { 638 if (sc->peers[i] == NULL) 639 continue; 640 if (sc->peers[i]->peerid != peerid) 641 continue; 642 643 peer = sc->peers[i]; 644 break; 645 } 646 if (i == OVPN_MAX_PEERS) 647 return (ENOENT); 648 649 sc->peers[i] = NULL; 650 sc->peercount--; 651 652 ovpn_peer_release_ref(peer, true); 653 654 return (0); 655 } 656 657 static int 658 ovpn_del_peer(struct ifnet *ifp, nvlist_t *nvl) 659 { 660 struct ovpn_softc *sc = ifp->if_softc; 661 uint32_t peerid; 662 int ret; 663 664 OVPN_WASSERT(sc); 665 666 if (nvl == NULL) 667 return (EINVAL); 668 669 if (! nvlist_exists_number(nvl, "peerid")) 670 return (EINVAL); 671 672 peerid = nvlist_get_number(nvl, "peerid"); 673 674 ret = _ovpn_del_peer(sc, peerid); 675 676 return (ret); 677 } 678 679 static int 680 ovpn_create_kkey_dir(struct ovpn_kkey_dir **kdirp, 681 const nvlist_t *nvl) 682 { 683 struct crypto_session_params csp; 684 struct ovpn_kkey_dir *kdir; 685 const char *ciphername; 686 enum ovpn_key_cipher cipher; 687 const void *key, *iv; 688 size_t keylen = 0, ivlen = 0; 689 int error; 690 691 if (! nvlist_exists_string(nvl, "cipher")) 692 return (EINVAL); 693 ciphername = nvlist_get_string(nvl, "cipher"); 694 695 if (strcmp(ciphername, "none") == 0) 696 cipher = OVPN_CIPHER_ALG_NONE; 697 else if (strcmp(ciphername, "AES-256-GCM") == 0) 698 cipher = OVPN_CIPHER_ALG_AES_GCM; 699 else if (strcmp(ciphername, "CHACHA20-POLY1305") == 0) 700 cipher = OVPN_CIPHER_ALG_CHACHA20_POLY1305; 701 else 702 return (EINVAL); 703 704 if (cipher != OVPN_CIPHER_ALG_NONE) { 705 if (! nvlist_exists_binary(nvl, "key")) 706 return (EINVAL); 707 key = nvlist_get_binary(nvl, "key", &keylen); 708 if (keylen > sizeof(kdir->key)) 709 return (E2BIG); 710 711 if (! nvlist_exists_binary(nvl, "iv")) 712 return (EINVAL); 713 iv = nvlist_get_binary(nvl, "iv", &ivlen); 714 if (ivlen != 8) 715 return (E2BIG); 716 } 717 718 kdir = malloc(sizeof(struct ovpn_kkey_dir), M_OVPN, 719 M_WAITOK | M_ZERO); 720 721 kdir->cipher = cipher; 722 kdir->keylen = keylen; 723 memcpy(kdir->key, key, keylen); 724 kdir->noncelen = ivlen; 725 memcpy(kdir->nonce, iv, ivlen); 726 727 if (kdir->cipher != OVPN_CIPHER_ALG_NONE) { 728 /* Crypto init */ 729 bzero(&csp, sizeof(csp)); 730 csp.csp_mode = CSP_MODE_AEAD; 731 732 if (kdir->cipher == OVPN_CIPHER_ALG_CHACHA20_POLY1305) 733 csp.csp_cipher_alg = CRYPTO_CHACHA20_POLY1305; 734 else 735 csp.csp_cipher_alg = CRYPTO_AES_NIST_GCM_16; 736 737 csp.csp_flags |= CSP_F_SEPARATE_AAD; 738 739 csp.csp_cipher_klen = kdir->keylen; 740 csp.csp_cipher_key = kdir->key; 741 csp.csp_ivlen = 96 / 8; 742 743 error = crypto_newsession(&kdir->cryptoid, &csp, 744 CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE); 745 if (error) { 746 free(kdir, M_OVPN); 747 return (error); 748 } 749 } 750 751 mtx_init(&kdir->replay_mtx, "if_ovpn rx replay", NULL, MTX_DEF); 752 *kdirp = kdir; 753 754 return (0); 755 } 756 757 static void 758 ovpn_free_kkey_dir(struct ovpn_kkey_dir *kdir) 759 { 760 if (kdir == NULL) 761 return; 762 763 mtx_destroy(&kdir->replay_mtx); 764 765 crypto_freesession(kdir->cryptoid); 766 free(kdir, M_OVPN); 767 } 768 769 static int 770 ovpn_set_key(struct ifnet *ifp, const nvlist_t *nvl) 771 { 772 struct ovpn_softc *sc = ifp->if_softc; 773 struct ovpn_kkey_dir *enc, *dec; 774 struct ovpn_kpeer *peer; 775 int slot, keyid, peerid; 776 int error; 777 778 if (nvl == NULL) 779 return (EINVAL); 780 781 if (! nvlist_exists_number(nvl, "slot")) 782 return (EINVAL); 783 slot = nvlist_get_number(nvl, "slot"); 784 785 if (! nvlist_exists_number(nvl, "keyid")) 786 return (EINVAL); 787 keyid = nvlist_get_number(nvl, "keyid"); 788 789 if (! nvlist_exists_number(nvl, "peerid")) 790 return (EINVAL); 791 peerid = nvlist_get_number(nvl, "peerid"); 792 793 if (slot != OVPN_KEY_SLOT_PRIMARY && 794 slot != OVPN_KEY_SLOT_SECONDARY) 795 return (EINVAL); 796 797 if (! nvlist_exists_nvlist(nvl, "encrypt") || 798 ! nvlist_exists_nvlist(nvl, "decrypt")) 799 return (EINVAL); 800 801 error = ovpn_create_kkey_dir(&enc, nvlist_get_nvlist(nvl, "encrypt")); 802 if (error) 803 return (error); 804 805 error = ovpn_create_kkey_dir(&dec, nvlist_get_nvlist(nvl, "decrypt")); 806 if (error) { 807 ovpn_free_kkey_dir(enc); 808 return (error); 809 } 810 811 OVPN_WLOCK(sc); 812 813 peer = ovpn_find_peer(sc, peerid); 814 if (peer == NULL) { 815 ovpn_free_kkey_dir(dec); 816 ovpn_free_kkey_dir(enc); 817 OVPN_WUNLOCK(sc); 818 return (ENOENT); 819 } 820 821 ovpn_free_kkey_dir(peer->keys[slot].encrypt); 822 ovpn_free_kkey_dir(peer->keys[slot].decrypt); 823 824 peer->keys[slot].encrypt = enc; 825 peer->keys[slot].decrypt = dec; 826 827 peer->keys[slot].keyid = keyid; 828 peer->keys[slot].peerid = peerid; 829 830 OVPN_WUNLOCK(sc); 831 832 return (0); 833 } 834 835 static int 836 ovpn_check_key(struct ovpn_softc *sc, struct ovpn_kpeer *peer, enum ovpn_key_slot slot) 837 { 838 OVPN_ASSERT(sc); 839 840 if (peer->keys[slot].encrypt == NULL) 841 return (ENOLINK); 842 843 if (peer->keys[slot].decrypt == NULL) 844 return (ENOLINK); 845 846 return (0); 847 } 848 849 static int 850 ovpn_start(struct ifnet *ifp) 851 { 852 struct ovpn_softc *sc = ifp->if_softc; 853 854 OVPN_WLOCK(sc); 855 856 ifp->if_flags |= IFF_UP; 857 ifp->if_drv_flags |= IFF_DRV_RUNNING; 858 if_link_state_change(ifp, LINK_STATE_UP); 859 860 OVPN_WUNLOCK(sc); 861 862 return (0); 863 } 864 865 static int 866 ovpn_swap_keys(struct ifnet *ifp, nvlist_t *nvl) 867 { 868 struct ovpn_softc *sc = ifp->if_softc; 869 struct ovpn_kpeer *peer; 870 struct ovpn_kkey tmpkey; 871 int error; 872 873 if (nvl == NULL) 874 return (EINVAL); 875 876 if (! nvlist_exists_number(nvl, "peerid")) 877 return (EINVAL); 878 879 OVPN_WLOCK(sc); 880 881 peer = ovpn_find_peer(sc, nvlist_get_number(nvl, "peerid")); 882 if (peer == NULL) { 883 OVPN_WUNLOCK(sc); 884 return (ENOENT); 885 } 886 887 /* Check that we have a second key to swap to. */ 888 error = ovpn_check_key(sc, peer, OVPN_KEY_SLOT_SECONDARY); 889 if (error) { 890 OVPN_WUNLOCK(sc); 891 return (error); 892 } 893 894 tmpkey = peer->keys[0]; 895 peer->keys[0] = peer->keys[1]; 896 peer->keys[1] = tmpkey; 897 898 OVPN_WUNLOCK(sc); 899 900 return (0); 901 } 902 903 static int 904 ovpn_del_key(struct ifnet *ifp, const nvlist_t *nvl) 905 { 906 enum ovpn_key_slot slot; 907 struct ovpn_kpeer *peer; 908 struct ovpn_softc *sc = ifp->if_softc; 909 910 if (nvl == NULL) 911 return (EINVAL); 912 913 if (! nvlist_exists_number(nvl, "peerid")) 914 return (EINVAL); 915 916 if (! nvlist_exists_number(nvl, "slot")) 917 return (EINVAL); 918 slot = nvlist_get_number(nvl, "slot"); 919 920 if (slot != OVPN_KEY_SLOT_PRIMARY && 921 slot != OVPN_KEY_SLOT_SECONDARY) 922 return (EINVAL); 923 924 OVPN_WLOCK(sc); 925 926 peer = ovpn_find_peer(sc, nvlist_get_number(nvl, "peerid")); 927 if (peer == NULL) { 928 OVPN_WUNLOCK(sc); 929 return (ENOENT); 930 } 931 932 ovpn_free_kkey_dir(peer->keys[slot].encrypt); 933 ovpn_free_kkey_dir(peer->keys[slot].decrypt); 934 935 peer->keys[slot].encrypt = NULL; 936 peer->keys[slot].decrypt = NULL; 937 938 peer->keys[slot].keyid = 0; 939 peer->keys[slot].peerid = 0; 940 941 OVPN_WUNLOCK(sc); 942 943 return (0); 944 } 945 946 static int 947 ovpn_send_pkt(struct ifnet *ifp, const nvlist_t *nvl) 948 { 949 struct epoch_tracker et; 950 struct ovpn_softc *sc = ifp->if_softc; 951 struct mbuf *m; 952 const uint8_t *pkt; 953 size_t pktlen; 954 uint32_t peerid; 955 int ret; 956 957 if (nvl == NULL) 958 return (EINVAL); 959 960 if (! nvlist_exists_binary(nvl, "packet")) 961 return (EINVAL); 962 pkt = nvlist_get_binary(nvl, "packet", &pktlen); 963 964 if (! nvlist_exists_number(nvl, "peerid")) 965 return (EINVAL); 966 967 peerid = nvlist_get_number(nvl, "peerid"); 968 969 /* 970 * Check that userspace isn't giving us a data packet. That might lead 971 * to IV re-use, which would be bad. 972 */ 973 if ((pkt[0] >> OVPN_OP_SHIFT) == OVPN_OP_DATA_V2) 974 return (EINVAL); 975 976 m = m_get2(pktlen, M_WAITOK, MT_DATA, M_PKTHDR); 977 if (m == NULL) 978 return (ENOMEM); 979 980 m->m_len = m->m_pkthdr.len = pktlen; 981 m_copyback(m, 0, m->m_len, pkt); 982 983 /* Now prepend IP/UDP headers and transmit the mbuf. */ 984 NET_EPOCH_ENTER(et); 985 ret = ovpn_encap(sc, peerid, m); 986 NET_EPOCH_EXIT(et); 987 if (ret == 0) 988 OVPN_COUNTER_ADD(sc, sent_ctrl_pkts, 1); 989 else 990 OVPN_COUNTER_ADD(sc, lost_ctrl_pkts_out, 1); 991 992 return (ret); 993 } 994 995 static void 996 ovpn_send_ping(void *arg) 997 { 998 static const uint8_t ping_str[] = { 999 0x2a, 0x18, 0x7b, 0xf3, 0x64, 0x1e, 0xb4, 0xcb, 1000 0x07, 0xed, 0x2d, 0x0a, 0x98, 0x1f, 0xc7, 0x48 1001 }; 1002 1003 struct epoch_tracker et; 1004 struct ovpn_kpeer *peer = arg; 1005 struct ovpn_softc *sc = peer->sc; 1006 struct mbuf *m; 1007 1008 OVPN_RASSERT(sc); 1009 1010 /* Ensure we repeat! */ 1011 callout_reset(&peer->ping_send, peer->keepalive.interval * hz, 1012 ovpn_send_ping, peer); 1013 1014 m = m_get2(sizeof(ping_str), M_NOWAIT, MT_DATA, M_PKTHDR); 1015 if (m == NULL) 1016 return; 1017 1018 m_copyback(m, 0, sizeof(ping_str), ping_str); 1019 m->m_len = m->m_pkthdr.len = sizeof(ping_str); 1020 1021 CURVNET_SET(sc->ifp->if_vnet); 1022 NET_EPOCH_ENTER(et); 1023 (void)ovpn_transmit_to_peer(sc->ifp, m, peer, NULL); 1024 NET_EPOCH_EXIT(et); 1025 CURVNET_RESTORE(); 1026 } 1027 1028 static void 1029 ovpn_timeout(void *arg) 1030 { 1031 struct ovpn_kpeer *peer = arg; 1032 struct ovpn_softc *sc = peer->sc; 1033 uint32_t last, _last_active; 1034 int ret __diagused; 1035 int cpu; 1036 1037 OVPN_WASSERT(sc); 1038 1039 last = 0; 1040 CPU_FOREACH(cpu) { 1041 _last_active = *zpcpu_get_cpu(peer->last_active, cpu); 1042 if (_last_active > last) 1043 last = _last_active; 1044 } 1045 1046 if (last + peer->keepalive.timeout > time_uptime) { 1047 callout_reset(&peer->ping_rcv, 1048 (peer->keepalive.timeout - (time_uptime - last)) * hz, 1049 ovpn_timeout, peer); 1050 return; 1051 } 1052 1053 CURVNET_SET(sc->ifp->if_vnet); 1054 ret = _ovpn_del_peer(sc, peer->peerid); 1055 MPASS(ret == 0); 1056 CURVNET_RESTORE(); 1057 } 1058 1059 static int 1060 ovpn_set_peer(struct ifnet *ifp, const nvlist_t *nvl) 1061 { 1062 struct ovpn_softc *sc = ifp->if_softc; 1063 struct ovpn_kpeer *peer; 1064 1065 if (nvl == NULL) 1066 return (EINVAL); 1067 1068 if (! nvlist_exists_number(nvl, "interval") || 1069 ! nvlist_exists_number(nvl, "timeout") || 1070 ! nvlist_exists_number(nvl, "peerid")) 1071 return (EINVAL); 1072 1073 OVPN_WLOCK(sc); 1074 1075 peer = ovpn_find_peer(sc, nvlist_get_number(nvl, "peerid")); 1076 if (peer == NULL) { 1077 OVPN_WUNLOCK(sc); 1078 return (ENOENT); 1079 } 1080 1081 peer->keepalive.interval = nvlist_get_number(nvl, "interval"); 1082 peer->keepalive.timeout = nvlist_get_number(nvl, "timeout"); 1083 1084 if (peer->keepalive.interval > 0) 1085 callout_reset(&peer->ping_send, peer->keepalive.interval * hz, 1086 ovpn_send_ping, peer); 1087 if (peer->keepalive.timeout > 0) 1088 callout_reset(&peer->ping_rcv, peer->keepalive.timeout * hz, 1089 ovpn_timeout, peer); 1090 1091 OVPN_WUNLOCK(sc); 1092 1093 return (0); 1094 } 1095 1096 static int 1097 ovpn_set_ifmode(struct ifnet *ifp, const nvlist_t *nvl) 1098 { 1099 struct ovpn_softc *sc = ifp->if_softc; 1100 int ifmode; 1101 1102 if (nvl == NULL) 1103 return (EINVAL); 1104 1105 if (! nvlist_exists_number(nvl, "ifmode") ) 1106 return (EINVAL); 1107 1108 ifmode = nvlist_get_number(nvl, "ifmode"); 1109 1110 OVPN_WLOCK(sc); 1111 1112 /* deny this if UP */ 1113 if (ifp->if_flags & IFF_UP) { 1114 OVPN_WUNLOCK(sc); 1115 return (EBUSY); 1116 } 1117 1118 switch (ifmode & ~IFF_MULTICAST) { 1119 case IFF_POINTOPOINT: 1120 case IFF_BROADCAST: 1121 ifp->if_flags &= 1122 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 1123 ifp->if_flags |= ifmode; 1124 break; 1125 default: 1126 OVPN_WUNLOCK(sc); 1127 return (EINVAL); 1128 } 1129 1130 OVPN_WUNLOCK(sc); 1131 1132 return (0); 1133 } 1134 1135 static int 1136 ovpn_ioctl_set(struct ifnet *ifp, struct ifdrv *ifd) 1137 { 1138 struct ovpn_softc *sc = ifp->if_softc; 1139 uint8_t *buf = NULL; 1140 nvlist_t *nvl = NULL; 1141 int ret; 1142 1143 if (ifd->ifd_len != 0) { 1144 if (ifd->ifd_len > OVPN_MAX_REQUEST_SIZE) 1145 return (E2BIG); 1146 1147 buf = malloc(ifd->ifd_len, M_OVPN, M_WAITOK); 1148 1149 ret = copyin(ifd->ifd_data, buf, ifd->ifd_len); 1150 if (ret != 0) { 1151 free(buf, M_OVPN); 1152 return (ret); 1153 } 1154 1155 nvl = nvlist_unpack(buf, ifd->ifd_len, 0); 1156 free(buf, M_OVPN); 1157 if (nvl == NULL) { 1158 return (EINVAL); 1159 } 1160 } 1161 1162 switch (ifd->ifd_cmd) { 1163 case OVPN_NEW_PEER: 1164 ret = ovpn_new_peer(ifp, nvl); 1165 break; 1166 case OVPN_DEL_PEER: 1167 OVPN_WLOCK(sc); 1168 ret = ovpn_del_peer(ifp, nvl); 1169 OVPN_WUNLOCK(sc); 1170 break; 1171 case OVPN_NEW_KEY: 1172 ret = ovpn_set_key(ifp, nvl); 1173 break; 1174 case OVPN_START_VPN: 1175 ret = ovpn_start(ifp); 1176 break; 1177 case OVPN_SWAP_KEYS: 1178 ret = ovpn_swap_keys(ifp, nvl); 1179 break; 1180 case OVPN_DEL_KEY: 1181 ret = ovpn_del_key(ifp, nvl); 1182 break; 1183 case OVPN_SEND_PKT: 1184 ret = ovpn_send_pkt(ifp, nvl); 1185 break; 1186 case OVPN_SET_PEER: 1187 ret = ovpn_set_peer(ifp, nvl); 1188 break; 1189 case OVPN_SET_IFMODE: 1190 ret = ovpn_set_ifmode(ifp, nvl); 1191 break; 1192 default: 1193 ret = ENOTSUP; 1194 } 1195 1196 nvlist_destroy(nvl); 1197 return (ret); 1198 } 1199 1200 static int 1201 ovpn_add_counters(nvlist_t *parent, const char *name, counter_u64_t in, 1202 counter_u64_t out) 1203 { 1204 nvlist_t *nvl; 1205 1206 nvl = nvlist_create(0); 1207 if (nvl == NULL) 1208 return (ENOMEM); 1209 1210 nvlist_add_number(nvl, "in", counter_u64_fetch(in)); 1211 nvlist_add_number(nvl, "out", counter_u64_fetch(out)); 1212 1213 nvlist_add_nvlist(parent, name, nvl); 1214 1215 nvlist_destroy(nvl); 1216 1217 return (0); 1218 } 1219 1220 static int 1221 ovpn_get_stats(struct ovpn_softc *sc, nvlist_t **onvl) 1222 { 1223 nvlist_t *nvl; 1224 int ret; 1225 1226 nvl = nvlist_create(0); 1227 if (nvl == NULL) 1228 return (ENOMEM); 1229 1230 #define OVPN_COUNTER_OUT(name, in, out) \ 1231 do { \ 1232 ret = ovpn_add_counters(nvl, name, \ 1233 sc->counters[offsetof(struct ovpn_counters, in) / \ 1234 sizeof(uint64_t)], \ 1235 sc->counters[offsetof(struct ovpn_counters, out) / \ 1236 sizeof(uint64_t)]); \ 1237 if (ret != 0) \ 1238 goto error; \ 1239 } while(0) 1240 1241 OVPN_COUNTER_OUT("lost_ctrl", lost_ctrl_pkts_in, lost_ctrl_pkts_out); 1242 OVPN_COUNTER_OUT("lost_data", lost_data_pkts_in, lost_data_pkts_out); 1243 OVPN_COUNTER_OUT("nomem_data", nomem_data_pkts_in, 1244 nomem_data_pkts_out); 1245 OVPN_COUNTER_OUT("data", received_data_pkts, sent_data_pkts); 1246 OVPN_COUNTER_OUT("ctrl", received_ctrl_pkts, sent_ctrl_pkts); 1247 OVPN_COUNTER_OUT("tunnel", tunnel_bytes_received, 1248 tunnel_bytes_received); 1249 OVPN_COUNTER_OUT("transport", transport_bytes_received, 1250 transport_bytes_received); 1251 #undef OVPN_COUNTER_OUT 1252 1253 *onvl = nvl; 1254 1255 return (0); 1256 1257 error: 1258 nvlist_destroy(nvl); 1259 return (ret); 1260 } 1261 1262 static int 1263 ovpn_poll_pkt(struct ovpn_softc *sc, nvlist_t **onvl) 1264 { 1265 nvlist_t *nvl; 1266 1267 nvl = nvlist_create(0); 1268 if (nvl == NULL) 1269 return (ENOMEM); 1270 1271 nvlist_add_number(nvl, "pending", 1272 buf_ring_count(sc->rxring) + buf_ring_count(sc->notifring)); 1273 1274 *onvl = nvl; 1275 1276 return (0); 1277 } 1278 1279 static int 1280 opvn_get_pkt(struct ovpn_softc *sc, nvlist_t **onvl) 1281 { 1282 struct ovpn_notification *n; 1283 struct ovpn_wire_header *ohdr; 1284 struct mbuf *m; 1285 uint8_t *buf; 1286 nvlist_t *nvl; 1287 uint32_t peerid; 1288 u_int mlength; 1289 1290 /* Check if we have notifications pending. */ 1291 n = buf_ring_dequeue_mc(sc->notifring); 1292 if (n != NULL) { 1293 nvl = nvlist_create(0); 1294 if (nvl == NULL) { 1295 free(n, M_OVPN); 1296 return (ENOMEM); 1297 } 1298 nvlist_add_number(nvl, "peerid", n->peerid); 1299 nvlist_add_number(nvl, "notification", n->type); 1300 free(n, M_OVPN); 1301 1302 *onvl = nvl; 1303 1304 return (0); 1305 } 1306 1307 /* Queued packet. */ 1308 m = buf_ring_dequeue_mc(sc->rxring); 1309 if (m == NULL) 1310 return (ENOENT); 1311 1312 mlength = m_length(m, NULL); 1313 buf = malloc(mlength, M_NVLIST, M_WAITOK); 1314 m_copydata(m, 0, mlength, buf); 1315 ohdr = (struct ovpn_wire_header *)buf; 1316 peerid = ntohl(ohdr->opcode) & 0x00ffffff; 1317 1318 nvl = nvlist_create(0); 1319 if (nvl == NULL) { 1320 OVPN_COUNTER_ADD(sc, lost_ctrl_pkts_in, 1); 1321 m_freem(m); 1322 free(buf, M_NVLIST); 1323 return (ENOMEM); 1324 } 1325 1326 nvlist_move_binary(nvl, "packet", buf, mlength); 1327 buf = NULL; 1328 nvlist_add_number(nvl, "peerid", peerid); 1329 1330 *onvl = nvl; 1331 1332 m_freem(m); 1333 1334 return (0); 1335 } 1336 1337 static int 1338 ovpn_ioctl_get(struct ifnet *ifp, struct ifdrv *ifd) 1339 { 1340 struct ovpn_softc *sc = ifp->if_softc; 1341 nvlist_t *nvl = NULL; 1342 int error; 1343 1344 switch (ifd->ifd_cmd) { 1345 case OVPN_GET_STATS: 1346 error = ovpn_get_stats(sc, &nvl); 1347 break; 1348 case OVPN_POLL_PKT: 1349 error = ovpn_poll_pkt(sc, &nvl); 1350 break; 1351 case OVPN_GET_PKT: 1352 error = opvn_get_pkt(sc, &nvl); 1353 break; 1354 default: 1355 error = ENOTSUP; 1356 break; 1357 } 1358 1359 if (error == 0) { 1360 void *packed = NULL; 1361 size_t len; 1362 1363 MPASS(nvl != NULL); 1364 1365 packed = nvlist_pack(nvl, &len); 1366 if (! packed) { 1367 nvlist_destroy(nvl); 1368 return (ENOMEM); 1369 } 1370 1371 if (len > ifd->ifd_len) { 1372 free(packed, M_NVLIST); 1373 nvlist_destroy(nvl); 1374 return (ENOSPC); 1375 } 1376 1377 error = copyout(packed, ifd->ifd_data, len); 1378 ifd->ifd_len = len; 1379 1380 free(packed, M_NVLIST); 1381 nvlist_destroy(nvl); 1382 } 1383 1384 return (error); 1385 } 1386 1387 static int 1388 ovpn_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1389 { 1390 struct ifdrv *ifd; 1391 int error; 1392 1393 switch (cmd) { 1394 case SIOCSDRVSPEC: 1395 case SIOCGDRVSPEC: 1396 error = priv_check(curthread, PRIV_NET_OVPN); 1397 if (error) 1398 return (error); 1399 break; 1400 } 1401 1402 switch (cmd) { 1403 case SIOCSDRVSPEC: 1404 ifd = (struct ifdrv *)data; 1405 error = ovpn_ioctl_set(ifp, ifd); 1406 break; 1407 case SIOCGDRVSPEC: 1408 ifd = (struct ifdrv *)data; 1409 error = ovpn_ioctl_get(ifp, ifd); 1410 break; 1411 case SIOCSIFMTU: { 1412 struct ifreq *ifr = (struct ifreq *)data; 1413 if (ifr->ifr_mtu < OVPN_MTU_MIN || ifr->ifr_mtu > OVPN_MTU_MAX) 1414 return (EINVAL); 1415 1416 ifp->if_mtu = ifr->ifr_mtu; 1417 return (0); 1418 } 1419 case SIOCSIFADDR: 1420 case SIOCADDMULTI: 1421 case SIOCDELMULTI: 1422 case SIOCGIFMTU: 1423 case SIOCSIFFLAGS: 1424 return (0); 1425 default: 1426 error = EINVAL; 1427 } 1428 1429 return (error); 1430 } 1431 1432 static int 1433 ovpn_encrypt_tx_cb(struct cryptop *crp) 1434 { 1435 struct epoch_tracker et; 1436 struct ovpn_kpeer *peer = crp->crp_opaque; 1437 struct ovpn_softc *sc = peer->sc; 1438 struct mbuf *m = crp->crp_buf.cb_mbuf; 1439 int tunnel_len; 1440 int ret; 1441 1442 if (crp->crp_etype != 0) { 1443 crypto_freereq(crp); 1444 ovpn_peer_release_ref(peer, false); 1445 OVPN_COUNTER_ADD(sc, lost_data_pkts_out, 1); 1446 m_freem(m); 1447 return (0); 1448 } 1449 1450 NET_EPOCH_ENTER(et); 1451 CURVNET_SET(sc->ifp->if_vnet); 1452 1453 MPASS(crp->crp_buf.cb_type == CRYPTO_BUF_MBUF); 1454 1455 tunnel_len = m->m_pkthdr.len - sizeof(struct ovpn_wire_header); 1456 ret = ovpn_encap(sc, peer->peerid, m); 1457 if (ret == 0) { 1458 OVPN_COUNTER_ADD(sc, sent_data_pkts, 1); 1459 OVPN_COUNTER_ADD(sc, tunnel_bytes_sent, tunnel_len); 1460 } 1461 1462 CURVNET_RESTORE(); 1463 NET_EPOCH_EXIT(et); 1464 1465 crypto_freereq(crp); 1466 ovpn_peer_release_ref(peer, false); 1467 1468 return (0); 1469 } 1470 1471 static void 1472 ovpn_finish_rx(struct ovpn_softc *sc, struct mbuf *m, 1473 struct ovpn_kpeer *peer, struct ovpn_kkey *key, uint32_t seq, 1474 struct rm_priotracker *_ovpn_lock_trackerp) 1475 { 1476 uint32_t af; 1477 1478 OVPN_RASSERT(sc); 1479 NET_EPOCH_ASSERT(); 1480 1481 /* Replay protection. */ 1482 if (V_replay_protection && ! ovpn_check_replay(key->decrypt, seq)) { 1483 OVPN_RUNLOCK(sc); 1484 OVPN_COUNTER_ADD(sc, lost_data_pkts_in, 1); 1485 m_freem(m); 1486 return; 1487 } 1488 1489 critical_enter(); 1490 *zpcpu_get(peer->last_active) = time_uptime; 1491 critical_exit(); 1492 1493 OVPN_RUNLOCK(sc); 1494 1495 OVPN_COUNTER_ADD(sc, received_data_pkts, 1); 1496 OVPN_COUNTER_ADD(sc, tunnel_bytes_received, m->m_pkthdr.len); 1497 1498 /* Receive the packet on our interface. */ 1499 m->m_pkthdr.rcvif = sc->ifp; 1500 1501 /* Clear checksum flags in case the real hardware set them. */ 1502 m->m_pkthdr.csum_flags = 0; 1503 1504 /* Ensure we can read the first byte. */ 1505 m = m_pullup(m, 1); 1506 if (m == NULL) { 1507 OVPN_COUNTER_ADD(sc, nomem_data_pkts_in, 1); 1508 return; 1509 } 1510 1511 /* 1512 * Check for address family, and disregard any control packets (e.g. 1513 * keepalive). 1514 */ 1515 af = ovpn_get_af(m); 1516 if (af != 0) { 1517 BPF_MTAP2(sc->ifp, &af, sizeof(af), m); 1518 if (V_async_netisr_queue) 1519 netisr_queue(af == AF_INET ? NETISR_IP : NETISR_IPV6, m); 1520 else 1521 netisr_dispatch(af == AF_INET ? NETISR_IP : NETISR_IPV6, m); 1522 } else { 1523 OVPN_COUNTER_ADD(sc, lost_data_pkts_in, 1); 1524 m_freem(m); 1525 } 1526 } 1527 1528 static struct ovpn_kkey * 1529 ovpn_find_key(struct ovpn_softc *sc, struct ovpn_kpeer *peer, 1530 const struct ovpn_wire_header *ohdr) 1531 { 1532 struct ovpn_kkey *key = NULL; 1533 uint8_t keyid; 1534 1535 OVPN_RASSERT(sc); 1536 1537 keyid = (ntohl(ohdr->opcode) >> 24) & 0x07; 1538 1539 if (peer->keys[0].keyid == keyid) 1540 key = &peer->keys[0]; 1541 else if (peer->keys[1].keyid == keyid) 1542 key = &peer->keys[1]; 1543 1544 return (key); 1545 } 1546 1547 static int 1548 ovpn_decrypt_rx_cb(struct cryptop *crp) 1549 { 1550 struct epoch_tracker et; 1551 struct ovpn_softc *sc = crp->crp_opaque; 1552 struct mbuf *m = crp->crp_buf.cb_mbuf; 1553 struct ovpn_kkey *key; 1554 struct ovpn_kpeer *peer; 1555 struct ovpn_wire_header *ohdr; 1556 uint32_t peerid; 1557 1558 OVPN_RLOCK_TRACKER; 1559 1560 OVPN_RLOCK(sc); 1561 1562 MPASS(crp->crp_buf.cb_type == CRYPTO_BUF_MBUF); 1563 1564 if (crp->crp_etype != 0) { 1565 crypto_freereq(crp); 1566 atomic_add_int(&sc->refcount, -1); 1567 OVPN_COUNTER_ADD(sc, lost_data_pkts_in, 1); 1568 OVPN_RUNLOCK(sc); 1569 m_freem(m); 1570 return (0); 1571 } 1572 1573 CURVNET_SET(sc->ifp->if_vnet); 1574 1575 ohdr = mtodo(m, sizeof(struct udphdr)); 1576 1577 peerid = ntohl(ohdr->opcode) & 0x00ffffff; 1578 peer = ovpn_find_peer(sc, peerid); 1579 if (peer == NULL) { 1580 /* No such peer. Drop packet. */ 1581 crypto_freereq(crp); 1582 atomic_add_int(&sc->refcount, -1); 1583 OVPN_RUNLOCK(sc); 1584 OVPN_COUNTER_ADD(sc, lost_data_pkts_in, 1); 1585 m_freem(m); 1586 CURVNET_RESTORE(); 1587 return (0); 1588 } 1589 1590 key = ovpn_find_key(sc, peer, ohdr); 1591 if (key == NULL) { 1592 crypto_freereq(crp); 1593 atomic_add_int(&sc->refcount, -1); 1594 /* 1595 * Has this key been removed between us starting the decrypt 1596 * and finishing it? 1597 */ 1598 OVPN_RUNLOCK(sc); 1599 OVPN_COUNTER_ADD(sc, lost_data_pkts_in, 1); 1600 m_freem(m); 1601 CURVNET_RESTORE(); 1602 return (0); 1603 } 1604 1605 /* Now remove the outer headers */ 1606 m_adj_decap(m, sizeof(struct udphdr) + 1607 sizeof(struct ovpn_wire_header)); 1608 1609 NET_EPOCH_ENTER(et); 1610 ovpn_finish_rx(sc, m, peer, key, ntohl(ohdr->seq), _ovpn_lock_trackerp); 1611 NET_EPOCH_EXIT(et); 1612 OVPN_UNLOCK_ASSERT(sc); 1613 1614 CURVNET_RESTORE(); 1615 1616 crypto_freereq(crp); 1617 atomic_add_int(&sc->refcount, -1); 1618 1619 return (0); 1620 } 1621 1622 static int 1623 ovpn_get_af(struct mbuf *m) 1624 { 1625 struct ip *ip; 1626 struct ip6_hdr *ip6; 1627 1628 /* 1629 * We should pullup, but we're only interested in the first byte, so 1630 * that'll always be contiguous. 1631 */ 1632 ip = mtod(m, struct ip *); 1633 if (ip->ip_v == IPVERSION) 1634 return (AF_INET); 1635 1636 ip6 = mtod(m, struct ip6_hdr *); 1637 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) == IPV6_VERSION) 1638 return (AF_INET6); 1639 1640 return (0); 1641 } 1642 1643 #ifdef INET 1644 static struct ovpn_kpeer * 1645 ovpn_find_peer_by_ip(struct ovpn_softc *sc, const struct in_addr addr) 1646 { 1647 struct ovpn_kpeer *peer = NULL; 1648 1649 OVPN_ASSERT(sc); 1650 1651 for (int i = 0; i < OVPN_MAX_PEERS; i++) { 1652 if (sc->peers[i] == NULL) 1653 continue; 1654 if (addr.s_addr == sc->peers[i]->vpn4.s_addr) { 1655 peer = sc->peers[i]; 1656 break; 1657 } 1658 } 1659 1660 return (peer); 1661 } 1662 #endif 1663 1664 #ifdef INET6 1665 static struct ovpn_kpeer * 1666 ovpn_find_peer_by_ip6(struct ovpn_softc *sc, const struct in6_addr *addr) 1667 { 1668 struct ovpn_kpeer *peer = NULL; 1669 1670 OVPN_ASSERT(sc); 1671 1672 for (int i = 0; i < OVPN_MAX_PEERS; i++) { 1673 if (sc->peers[i] == NULL) 1674 continue; 1675 if (memcmp(addr, &sc->peers[i]->vpn6, sizeof(*addr)) == 0) { 1676 peer = sc->peers[i]; 1677 break; 1678 } 1679 } 1680 1681 return (peer); 1682 } 1683 #endif 1684 1685 static struct ovpn_kpeer * 1686 ovpn_route_peer(struct ovpn_softc *sc, struct mbuf **m0, 1687 const struct sockaddr *dst) 1688 { 1689 struct ovpn_kpeer *peer = NULL; 1690 int af; 1691 1692 NET_EPOCH_ASSERT(); 1693 OVPN_ASSERT(sc); 1694 1695 /* Shortcut if we're a client (or are a server and have only one client). */ 1696 if (sc->peercount == 1) 1697 return (ovpn_find_only_peer(sc)); 1698 1699 if (dst != NULL) 1700 af = dst->sa_family; 1701 else 1702 af = ovpn_get_af(*m0); 1703 1704 switch (af) { 1705 #ifdef INET 1706 case AF_INET: { 1707 const struct sockaddr_in *sa = (const struct sockaddr_in *)dst; 1708 struct nhop_object *nh; 1709 const struct in_addr *ip_dst; 1710 1711 if (sa != NULL) { 1712 ip_dst = &sa->sin_addr; 1713 } else { 1714 struct ip *ip; 1715 1716 *m0 = m_pullup(*m0, sizeof(struct ip)); 1717 if (*m0 == NULL) 1718 return (NULL); 1719 ip = mtod(*m0, struct ip *); 1720 ip_dst = &ip->ip_dst; 1721 } 1722 1723 peer = ovpn_find_peer_by_ip(sc, *ip_dst); 1724 SDT_PROBE2(if_ovpn, tx, route, ip4, ip_dst, peer); 1725 if (peer == NULL) { 1726 nh = fib4_lookup(M_GETFIB(*m0), *ip_dst, 0, 1727 NHR_NONE, 0); 1728 if (nh && (nh->nh_flags & NHF_GATEWAY)) { 1729 peer = ovpn_find_peer_by_ip(sc, 1730 nh->gw4_sa.sin_addr); 1731 SDT_PROBE2(if_ovpn, tx, route, ip4, 1732 &nh->gw4_sa.sin_addr, peer); 1733 } 1734 } 1735 break; 1736 } 1737 #endif 1738 #ifdef INET6 1739 case AF_INET6: { 1740 const struct sockaddr_in6 *sa6 = 1741 (const struct sockaddr_in6 *)dst; 1742 struct nhop_object *nh; 1743 const struct in6_addr *ip6_dst; 1744 1745 if (sa6 != NULL) { 1746 ip6_dst = &sa6->sin6_addr; 1747 } else { 1748 struct ip6_hdr *ip6; 1749 1750 *m0 = m_pullup(*m0, sizeof(struct ip6_hdr)); 1751 if (*m0 == NULL) 1752 return (NULL); 1753 ip6 = mtod(*m0, struct ip6_hdr *); 1754 ip6_dst = &ip6->ip6_dst; 1755 } 1756 1757 peer = ovpn_find_peer_by_ip6(sc, ip6_dst); 1758 SDT_PROBE2(if_ovpn, tx, route, ip6, ip6_dst, peer); 1759 if (peer == NULL) { 1760 nh = fib6_lookup(M_GETFIB(*m0), ip6_dst, 0, 1761 NHR_NONE, 0); 1762 if (nh && (nh->nh_flags & NHF_GATEWAY)) { 1763 peer = ovpn_find_peer_by_ip6(sc, 1764 &nh->gw6_sa.sin6_addr); 1765 SDT_PROBE2(if_ovpn, tx, route, ip6, 1766 &nh->gw6_sa.sin6_addr, peer); 1767 } 1768 } 1769 break; 1770 } 1771 #endif 1772 } 1773 1774 return (peer); 1775 } 1776 1777 static int 1778 ovpn_transmit(struct ifnet *ifp, struct mbuf *m) 1779 { 1780 return (ifp->if_output(ifp, m, NULL, NULL)); 1781 } 1782 1783 static int 1784 ovpn_transmit_to_peer(struct ifnet *ifp, struct mbuf *m, 1785 struct ovpn_kpeer *peer, struct rm_priotracker *_ovpn_lock_trackerp) 1786 { 1787 struct ovpn_wire_header *ohdr; 1788 struct ovpn_kkey *key; 1789 struct ovpn_softc *sc; 1790 struct cryptop *crp; 1791 uint32_t af, seq; 1792 size_t len, ovpn_hdr_len; 1793 int tunnel_len; 1794 int ret; 1795 1796 sc = ifp->if_softc; 1797 1798 OVPN_RASSERT(sc); 1799 1800 tunnel_len = m->m_pkthdr.len; 1801 1802 key = &peer->keys[OVPN_KEY_SLOT_PRIMARY]; 1803 if (key->encrypt == NULL) { 1804 if (_ovpn_lock_trackerp != NULL) 1805 OVPN_RUNLOCK(sc); 1806 m_freem(m); 1807 return (ENOLINK); 1808 } 1809 1810 af = ovpn_get_af(m); 1811 /* Don't capture control packets. */ 1812 if (af != 0) 1813 BPF_MTAP2(ifp, &af, sizeof(af), m); 1814 1815 len = m->m_pkthdr.len; 1816 MPASS(len <= ifp->if_mtu); 1817 1818 ovpn_hdr_len = sizeof(struct ovpn_wire_header); 1819 if (key->encrypt->cipher == OVPN_CIPHER_ALG_NONE) 1820 ovpn_hdr_len -= 16; /* No auth tag. */ 1821 1822 M_PREPEND(m, ovpn_hdr_len, M_NOWAIT); 1823 if (m == NULL) { 1824 if (_ovpn_lock_trackerp != NULL) 1825 OVPN_RUNLOCK(sc); 1826 OVPN_COUNTER_ADD(sc, nomem_data_pkts_out, 1); 1827 return (ENOBUFS); 1828 } 1829 ohdr = mtod(m, struct ovpn_wire_header *); 1830 ohdr->opcode = (OVPN_OP_DATA_V2 << OVPN_OP_SHIFT) | key->keyid; 1831 ohdr->opcode <<= 24; 1832 ohdr->opcode |= key->peerid; 1833 ohdr->opcode = htonl(ohdr->opcode); 1834 1835 seq = atomic_fetchadd_32(&peer->tx_seq, 1); 1836 seq = htonl(seq); 1837 ohdr->seq = seq; 1838 1839 if (key->encrypt->cipher == OVPN_CIPHER_ALG_NONE) { 1840 ret = ovpn_encap(sc, peer->peerid, m); 1841 if (_ovpn_lock_trackerp != NULL) 1842 OVPN_RUNLOCK(sc); 1843 if (ret == 0) { 1844 OVPN_COUNTER_ADD(sc, sent_data_pkts, 1); 1845 OVPN_COUNTER_ADD(sc, tunnel_bytes_sent, tunnel_len); 1846 } 1847 return (ret); 1848 } 1849 1850 crp = crypto_getreq(key->encrypt->cryptoid, M_NOWAIT); 1851 if (crp == NULL) { 1852 if (_ovpn_lock_trackerp != NULL) 1853 OVPN_RUNLOCK(sc); 1854 OVPN_COUNTER_ADD(sc, nomem_data_pkts_out, 1); 1855 m_freem(m); 1856 return (ENOBUFS); 1857 } 1858 1859 /* Encryption covers only the payload, not the header. */ 1860 crp->crp_payload_start = sizeof(*ohdr); 1861 crp->crp_payload_length = len; 1862 crp->crp_op = CRYPTO_OP_ENCRYPT; 1863 1864 /* 1865 * AAD data covers the ovpn_wire_header minus the auth 1866 * tag. 1867 */ 1868 crp->crp_aad_length = sizeof(*ohdr) - sizeof(ohdr->auth_tag); 1869 crp->crp_aad = ohdr; 1870 crp->crp_aad_start = 0; 1871 crp->crp_op |= CRYPTO_OP_COMPUTE_DIGEST; 1872 crp->crp_digest_start = offsetof(struct ovpn_wire_header, auth_tag); 1873 1874 crp->crp_flags |= CRYPTO_F_IV_SEPARATE; 1875 memcpy(crp->crp_iv, &seq, sizeof(seq)); 1876 memcpy(crp->crp_iv + sizeof(seq), key->encrypt->nonce, 1877 key->encrypt->noncelen); 1878 1879 crypto_use_mbuf(crp, m); 1880 crp->crp_flags |= CRYPTO_F_CBIFSYNC; 1881 crp->crp_callback = ovpn_encrypt_tx_cb; 1882 crp->crp_opaque = peer; 1883 1884 atomic_add_int(&peer->refcount, 1); 1885 if (_ovpn_lock_trackerp != NULL) 1886 OVPN_RUNLOCK(sc); 1887 if (V_async_crypto) 1888 ret = crypto_dispatch_async(crp, CRYPTO_ASYNC_ORDERED); 1889 else 1890 ret = crypto_dispatch(crp); 1891 if (ret) { 1892 OVPN_COUNTER_ADD(sc, lost_data_pkts_out, 1); 1893 } 1894 1895 return (ret); 1896 } 1897 1898 /* 1899 * Note: Expects to hold the read lock on entry, and will release it itself. 1900 */ 1901 static int 1902 ovpn_encap(struct ovpn_softc *sc, uint32_t peerid, struct mbuf *m) 1903 { 1904 struct udphdr *udp; 1905 struct ovpn_kpeer *peer; 1906 int len; 1907 1908 OVPN_RLOCK_TRACKER; 1909 1910 OVPN_RLOCK(sc); 1911 NET_EPOCH_ASSERT(); 1912 1913 peer = ovpn_find_peer(sc, peerid); 1914 if (peer == NULL || sc->ifp->if_link_state != LINK_STATE_UP) { 1915 OVPN_RUNLOCK(sc); 1916 OVPN_COUNTER_ADD(sc, lost_data_pkts_out, 1); 1917 m_freem(m); 1918 return (ENETDOWN); 1919 } 1920 1921 len = m->m_pkthdr.len; 1922 1923 M_PREPEND(m, sizeof(struct udphdr), M_NOWAIT); 1924 if (m == NULL) { 1925 OVPN_RUNLOCK(sc); 1926 OVPN_COUNTER_ADD(sc, nomem_data_pkts_out, 1); 1927 m_freem(m); 1928 return (ENOBUFS); 1929 } 1930 udp = mtod(m, struct udphdr *); 1931 1932 MPASS(peer->local.ss_family == peer->remote.ss_family); 1933 1934 udp->uh_sport = ovpn_get_port(&peer->local); 1935 udp->uh_dport = ovpn_get_port(&peer->remote); 1936 udp->uh_ulen = htons(sizeof(struct udphdr) + len); 1937 1938 switch (peer->remote.ss_family) { 1939 #ifdef INET 1940 case AF_INET: { 1941 struct sockaddr_in *in_local = TO_IN(&peer->local); 1942 struct sockaddr_in *in_remote = TO_IN(&peer->remote); 1943 struct ip *ip; 1944 1945 /* 1946 * This requires knowing the source IP, which we don't. Happily 1947 * we're allowed to keep this at 0, and the checksum won't do 1948 * anything the crypto won't already do. 1949 */ 1950 udp->uh_sum = 0; 1951 1952 /* Set the checksum flags so we recalculate checksums. */ 1953 m->m_pkthdr.csum_flags |= CSUM_IP; 1954 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1955 1956 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 1957 if (m == NULL) { 1958 OVPN_RUNLOCK(sc); 1959 OVPN_COUNTER_ADD(sc, nomem_data_pkts_out, 1); 1960 return (ENOBUFS); 1961 } 1962 ip = mtod(m, struct ip *); 1963 1964 ip->ip_tos = 0; 1965 ip->ip_len = htons(sizeof(struct ip) + sizeof(struct udphdr) + 1966 len); 1967 ip->ip_off = 0; 1968 ip->ip_ttl = V_ip_defttl; 1969 ip->ip_p = IPPROTO_UDP; 1970 ip->ip_sum = 0; 1971 if (in_local->sin_port != 0) 1972 ip->ip_src = in_local->sin_addr; 1973 else 1974 ip->ip_src.s_addr = INADDR_ANY; 1975 ip->ip_dst = in_remote->sin_addr; 1976 1977 OVPN_RUNLOCK(sc); 1978 OVPN_COUNTER_ADD(sc, transport_bytes_sent, m->m_pkthdr.len); 1979 1980 return (ip_output(m, NULL, NULL, 0, NULL, NULL)); 1981 } 1982 #endif 1983 #ifdef INET6 1984 case AF_INET6: { 1985 struct sockaddr_in6 *in6_local = TO_IN6(&peer->local); 1986 struct sockaddr_in6 *in6_remote = TO_IN6(&peer->remote); 1987 struct ip6_hdr *ip6; 1988 1989 M_PREPEND(m, sizeof(struct ip6_hdr), M_NOWAIT); 1990 if (m == NULL) { 1991 OVPN_RUNLOCK(sc); 1992 OVPN_COUNTER_ADD(sc, nomem_data_pkts_out, 1); 1993 return (ENOBUFS); 1994 } 1995 m = m_pullup(m, sizeof(*ip6) + sizeof(*udp)); 1996 if (m == NULL) { 1997 OVPN_RUNLOCK(sc); 1998 OVPN_COUNTER_ADD(sc, nomem_data_pkts_out, 1); 1999 return (ENOBUFS); 2000 } 2001 2002 ip6 = mtod(m, struct ip6_hdr *); 2003 2004 ip6->ip6_vfc = IPV6_VERSION; 2005 ip6->ip6_flow &= ~IPV6_FLOWINFO_MASK; 2006 ip6->ip6_plen = htons(sizeof(*ip6) + sizeof(struct udphdr) + 2007 len); 2008 ip6->ip6_nxt = IPPROTO_UDP; 2009 ip6->ip6_hlim = V_ip6_defhlim; 2010 2011 memcpy(&ip6->ip6_src, &in6_local->sin6_addr, 2012 sizeof(ip6->ip6_src)); 2013 memcpy(&ip6->ip6_dst, &in6_remote->sin6_addr, 2014 sizeof(ip6->ip6_dst)); 2015 2016 udp = mtodo(m, sizeof(*ip6)); 2017 udp->uh_sum = in6_cksum_pseudo(ip6, 2018 m->m_pkthdr.len - sizeof(struct ip6_hdr), 2019 IPPROTO_UDP, 0); 2020 2021 m->m_pkthdr.csum_flags |= CSUM_UDP_IPV6; 2022 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2023 2024 OVPN_RUNLOCK(sc); 2025 OVPN_COUNTER_ADD(sc, transport_bytes_sent, m->m_pkthdr.len); 2026 2027 return (ip6_output(m, NULL, NULL, IPV6_UNSPECSRC, NULL, NULL, 2028 NULL)); 2029 } 2030 #endif 2031 default: 2032 panic("Unsupported address family %d", 2033 peer->remote.ss_family); 2034 } 2035 } 2036 2037 static int 2038 ovpn_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 2039 struct route *ro) 2040 { 2041 struct ovpn_softc *sc; 2042 struct ovpn_kpeer *peer; 2043 2044 OVPN_RLOCK_TRACKER; 2045 2046 sc = ifp->if_softc; 2047 2048 OVPN_RLOCK(sc); 2049 2050 SDT_PROBE1(if_ovpn, tx, transmit, start, m); 2051 2052 if (__predict_false(ifp->if_link_state != LINK_STATE_UP)) { 2053 OVPN_COUNTER_ADD(sc, lost_data_pkts_out, 1); 2054 OVPN_RUNLOCK(sc); 2055 m_freem(m); 2056 return (ENETDOWN); 2057 } 2058 2059 /** 2060 * Only obey 'dst' (i.e. the gateway) if no route is supplied. 2061 * That's our indication that we're being called through pf's route-to, 2062 * and we should route according to 'dst' instead. We can't do so 2063 * consistently, because the usual openvpn configuration sets the first 2064 * non-server IP in the subnet as the gateway. If we always use that 2065 * one we'd end up routing all traffic to the first client. 2066 * tl;dr: 'ro == NULL' tells us pf is doing a route-to, and then but 2067 * only then, we should treat 'dst' as the destination. */ 2068 peer = ovpn_route_peer(sc, &m, ro == NULL ? dst : NULL); 2069 if (peer == NULL) { 2070 /* No destination. */ 2071 OVPN_COUNTER_ADD(sc, lost_data_pkts_out, 1); 2072 OVPN_RUNLOCK(sc); 2073 m_freem(m); 2074 return (ENETDOWN); 2075 } 2076 2077 return (ovpn_transmit_to_peer(ifp, m, peer, _ovpn_lock_trackerp)); 2078 } 2079 2080 static void 2081 ovpn_rcv_ctrl(struct ovpn_softc *sc, struct mbuf *m, int off) 2082 { 2083 /* Lop off the IP and UDP headers */ 2084 m_adj_decap(m, off); 2085 2086 /* Keep in the local ring until userspace fetches it. */ 2087 if (buf_ring_enqueue(sc->rxring, m) != 0) { 2088 OVPN_COUNTER_ADD(sc, lost_ctrl_pkts_in, 1); 2089 m_freem(m); 2090 return; 2091 } 2092 2093 OVPN_COUNTER_ADD(sc, received_ctrl_pkts, 1); 2094 } 2095 2096 static bool 2097 ovpn_check_replay(struct ovpn_kkey_dir *key, uint32_t seq) 2098 { 2099 uint32_t d; 2100 2101 mtx_lock(&key->replay_mtx); 2102 2103 /* Sequence number must be strictly greater than rx_seq */ 2104 if (seq <= key->rx_seq) { 2105 mtx_unlock(&key->replay_mtx); 2106 return (false); 2107 } 2108 2109 /* Large jump. The packet authenticated okay, so just accept that. */ 2110 if (seq > (key->rx_seq + (sizeof(key->rx_window) * 8))) { 2111 key->rx_seq = seq; 2112 key->rx_window = 0; 2113 mtx_unlock(&key->replay_mtx); 2114 return (true); 2115 } 2116 2117 /* Happy case. */ 2118 if ((seq == key->rx_seq + 1) && key->rx_window == 0) { 2119 key->rx_seq++; 2120 mtx_unlock(&key->replay_mtx); 2121 return (true); 2122 } 2123 2124 d = seq - key->rx_seq - 1; 2125 2126 if (key->rx_window & ((uint64_t)1 << d)) { 2127 /* Dupe! */ 2128 mtx_unlock(&key->replay_mtx); 2129 return (false); 2130 } 2131 2132 key->rx_window |= (uint64_t)1 << d; 2133 2134 while (key->rx_window & 1) { 2135 key->rx_seq++; 2136 key->rx_window >>= 1; 2137 } 2138 2139 mtx_unlock(&key->replay_mtx); 2140 2141 return (true); 2142 } 2143 2144 static struct ovpn_kpeer * 2145 ovpn_peer_from_mbuf(struct ovpn_softc *sc, struct mbuf *m, int off) 2146 { 2147 struct ovpn_wire_header ohdr; 2148 uint32_t peerid; 2149 const size_t hdrlen = sizeof(ohdr) - sizeof(ohdr.auth_tag); 2150 2151 OVPN_RASSERT(sc); 2152 2153 if (m_length(m, NULL) < (off + sizeof(struct udphdr) + hdrlen)) 2154 return (NULL); 2155 2156 m_copydata(m, off + sizeof(struct udphdr), hdrlen, (caddr_t)&ohdr); 2157 2158 peerid = ntohl(ohdr.opcode) & 0x00ffffff; 2159 2160 return (ovpn_find_peer(sc, peerid)); 2161 } 2162 2163 static bool 2164 ovpn_udp_input(struct mbuf *m, int off, struct inpcb *inp, 2165 const struct sockaddr *sa, void *ctx) 2166 { 2167 struct ovpn_softc *sc = ctx; 2168 struct ovpn_wire_header *ohdr; 2169 struct udphdr *uhdr; 2170 struct ovpn_kkey *key; 2171 struct cryptop *crp; 2172 struct ovpn_kpeer *peer; 2173 size_t ohdrlen; 2174 int ret; 2175 uint8_t op; 2176 2177 OVPN_RLOCK_TRACKER; 2178 2179 M_ASSERTPKTHDR(m); 2180 2181 OVPN_COUNTER_ADD(sc, transport_bytes_received, m->m_pkthdr.len - off); 2182 2183 ohdrlen = sizeof(*ohdr) - sizeof(ohdr->auth_tag); 2184 2185 OVPN_RLOCK(sc); 2186 2187 peer = ovpn_peer_from_mbuf(sc, m, off); 2188 if (peer == NULL) { 2189 OVPN_RUNLOCK(sc); 2190 return (false); 2191 } 2192 2193 m = m_pullup(m, off + sizeof(*uhdr) + ohdrlen); 2194 if (m == NULL) { 2195 OVPN_RUNLOCK(sc); 2196 OVPN_COUNTER_ADD(sc, nomem_data_pkts_in, 1); 2197 return (true); 2198 } 2199 uhdr = mtodo(m, off); 2200 ohdr = mtodo(m, off + sizeof(*uhdr)); 2201 2202 op = ntohl(ohdr->opcode) >> 24 >> OVPN_OP_SHIFT; 2203 2204 /* 2205 * Simplify things by getting rid of the preceding headers, we don't 2206 * care about them. 2207 */ 2208 m_adj_decap(m, off); 2209 2210 uhdr = mtodo(m, 0); 2211 ohdr = mtodo(m, sizeof(*uhdr)); 2212 2213 if (op != OVPN_OP_DATA_V2) { 2214 OVPN_RUNLOCK(sc); 2215 ovpn_rcv_ctrl(sc, m, sizeof(struct udphdr)); 2216 INP_WLOCK(inp); 2217 udp_notify(inp, EAGAIN); 2218 INP_WUNLOCK(inp); 2219 return (true); 2220 } 2221 2222 key = ovpn_find_key(sc, peer, ohdr); 2223 if (key == NULL || key->decrypt == NULL) { 2224 OVPN_RUNLOCK(sc); 2225 OVPN_COUNTER_ADD(sc, lost_data_pkts_in, 1); 2226 m_freem(m); 2227 return (true); 2228 } 2229 2230 if (key->decrypt->cipher == OVPN_CIPHER_ALG_NONE) { 2231 /* Now remove the outer headers */ 2232 m_adj_decap(m, sizeof(struct udphdr) + ohdrlen); 2233 2234 ohdr = mtodo(m, sizeof(*uhdr)); 2235 2236 ovpn_finish_rx(sc, m, peer, key, ntohl(ohdr->seq), 2237 _ovpn_lock_trackerp); 2238 OVPN_UNLOCK_ASSERT(sc); 2239 return (true); 2240 } 2241 2242 ohdrlen += sizeof(ohdr->auth_tag); 2243 2244 m = m_pullup(m, sizeof(*uhdr) + ohdrlen); 2245 if (m == NULL) { 2246 OVPN_RUNLOCK(sc); 2247 OVPN_COUNTER_ADD(sc, nomem_data_pkts_in, 1); 2248 return (true); 2249 } 2250 uhdr = mtodo(m, 0); 2251 ohdr = mtodo(m, sizeof(*uhdr)); 2252 2253 /* Decrypt */ 2254 crp = crypto_getreq(key->decrypt->cryptoid, M_NOWAIT); 2255 if (crp == NULL) { 2256 OVPN_COUNTER_ADD(sc, nomem_data_pkts_in, 1); 2257 OVPN_RUNLOCK(sc); 2258 m_freem(m); 2259 return (true); 2260 } 2261 2262 crp->crp_payload_start = sizeof(struct udphdr) + sizeof(*ohdr); 2263 crp->crp_payload_length = ntohs(uhdr->uh_ulen) - 2264 sizeof(*uhdr) - sizeof(*ohdr); 2265 crp->crp_op = CRYPTO_OP_DECRYPT; 2266 2267 /* AAD validation. */ 2268 crp->crp_aad_length = sizeof(*ohdr) - sizeof(ohdr->auth_tag); 2269 crp->crp_aad = ohdr; 2270 crp->crp_aad_start = 0; 2271 crp->crp_op |= CRYPTO_OP_VERIFY_DIGEST; 2272 crp->crp_digest_start = sizeof(struct udphdr) + 2273 offsetof(struct ovpn_wire_header, auth_tag); 2274 2275 crp->crp_flags |= CRYPTO_F_IV_SEPARATE; 2276 memcpy(crp->crp_iv, &ohdr->seq, sizeof(ohdr->seq)); 2277 memcpy(crp->crp_iv + sizeof(ohdr->seq), key->decrypt->nonce, 2278 key->decrypt->noncelen); 2279 2280 crypto_use_mbuf(crp, m); 2281 crp->crp_flags |= CRYPTO_F_CBIFSYNC; 2282 crp->crp_callback = ovpn_decrypt_rx_cb; 2283 crp->crp_opaque = sc; 2284 2285 atomic_add_int(&sc->refcount, 1); 2286 OVPN_RUNLOCK(sc); 2287 if (V_async_crypto) 2288 ret = crypto_dispatch_async(crp, CRYPTO_ASYNC_ORDERED); 2289 else 2290 ret = crypto_dispatch(crp); 2291 if (ret != 0) { 2292 OVPN_COUNTER_ADD(sc, lost_data_pkts_in, 1); 2293 } 2294 2295 return (true); 2296 } 2297 2298 static void 2299 ovpn_qflush(struct ifnet *ifp __unused) 2300 { 2301 2302 } 2303 2304 static void 2305 ovpn_flush_rxring(struct ovpn_softc *sc) 2306 { 2307 struct mbuf *m; 2308 struct ovpn_notification *n; 2309 2310 OVPN_WASSERT(sc); 2311 2312 while (! buf_ring_empty(sc->rxring)) { 2313 m = buf_ring_dequeue_sc(sc->rxring); 2314 m_freem(m); 2315 } 2316 2317 while (! buf_ring_empty(sc->notifring)) { 2318 n = buf_ring_dequeue_sc(sc->notifring); 2319 free(n, M_OVPN); 2320 } 2321 } 2322 2323 #ifdef VIMAGE 2324 static void 2325 ovpn_reassign(struct ifnet *ifp, struct vnet *new_vnet __unused, 2326 char *unused __unused) 2327 { 2328 struct ovpn_softc *sc = ifp->if_softc; 2329 int i; 2330 int ret __diagused; 2331 2332 i = 0; 2333 2334 OVPN_WLOCK(sc); 2335 2336 /* Flush keys & configuration. */ 2337 do { 2338 if (sc->peers[i] != NULL) { 2339 ret = _ovpn_del_peer(sc, sc->peers[i]->peerid); 2340 MPASS(ret == 0); 2341 } 2342 i++; 2343 } while (i < OVPN_MAX_PEERS); 2344 2345 ovpn_flush_rxring(sc); 2346 2347 OVPN_WUNLOCK(sc); 2348 } 2349 #endif 2350 2351 static int 2352 ovpn_clone_match(struct if_clone *ifc, const char *name) 2353 { 2354 /* 2355 * Allow all names that start with 'ovpn', specifically because pfSense 2356 * uses ovpnc1 / ovpns2 2357 */ 2358 return (strncmp(ovpnname, name, strlen(ovpnname)) == 0); 2359 } 2360 2361 static int 2362 ovpn_clone_create(struct if_clone *ifc, char *name, size_t len, 2363 struct ifc_data *ifd, struct ifnet **ifpp) 2364 { 2365 struct ovpn_softc *sc; 2366 struct ifnet *ifp; 2367 char *dp; 2368 int error, unit, wildcard; 2369 2370 /* Try to see if a special unit was requested. */ 2371 error = ifc_name2unit(name, &unit); 2372 if (error != 0) 2373 return (error); 2374 wildcard = (unit < 0); 2375 2376 error = ifc_alloc_unit(ifc, &unit); 2377 if (error != 0) 2378 return (error); 2379 2380 /* 2381 * If no unit had been given, we need to adjust the ifName. 2382 */ 2383 for (dp = name; *dp != '\0'; dp++); 2384 if (wildcard) { 2385 error = snprintf(dp, len - (dp - name), "%d", unit); 2386 if (error > len - (dp - name)) { 2387 /* ifName too long. */ 2388 ifc_free_unit(ifc, unit); 2389 return (ENOSPC); 2390 } 2391 dp += error; 2392 } 2393 2394 /* Make sure it doesn't already exist. */ 2395 if (ifunit(name) != NULL) 2396 return (EEXIST); 2397 2398 sc = malloc(sizeof(struct ovpn_softc), M_OVPN, M_WAITOK | M_ZERO); 2399 sc->ifp = if_alloc(IFT_ENC); 2400 rm_init_flags(&sc->lock, "if_ovpn_lock", RM_RECURSE); 2401 sc->refcount = 0; 2402 2403 sc->rxring = buf_ring_alloc(32, M_OVPN, M_WAITOK, NULL); 2404 sc->notifring = buf_ring_alloc(32, M_OVPN, M_WAITOK, NULL); 2405 2406 COUNTER_ARRAY_ALLOC(sc->counters, OVPN_COUNTER_SIZE, M_WAITOK); 2407 2408 ifp = sc->ifp; 2409 ifp->if_softc = sc; 2410 strlcpy(ifp->if_xname, name, IFNAMSIZ); 2411 ifp->if_dname = ovpngroupname; 2412 ifp->if_dunit = unit; 2413 2414 ifp->if_addrlen = 0; 2415 ifp->if_mtu = 1428; 2416 ifp->if_flags = IFF_POINTOPOINT | IFF_MULTICAST; 2417 ifp->if_ioctl = ovpn_ioctl; 2418 ifp->if_transmit = ovpn_transmit; 2419 ifp->if_output = ovpn_output; 2420 ifp->if_qflush = ovpn_qflush; 2421 #ifdef VIMAGE 2422 ifp->if_reassign = ovpn_reassign; 2423 #endif 2424 ifp->if_capabilities |= IFCAP_LINKSTATE; 2425 ifp->if_capenable |= IFCAP_LINKSTATE; 2426 2427 if_attach(ifp); 2428 bpfattach(ifp, DLT_NULL, sizeof(uint32_t)); 2429 *ifpp = ifp; 2430 2431 return (0); 2432 } 2433 2434 static void 2435 ovpn_clone_destroy_cb(struct epoch_context *ctx) 2436 { 2437 struct ovpn_softc *sc; 2438 2439 sc = __containerof(ctx, struct ovpn_softc, epoch_ctx); 2440 2441 MPASS(sc->peercount == 0); 2442 for (int i = 0; i < OVPN_MAX_PEERS; i++) { 2443 MPASS(sc->peers[i] == NULL); 2444 } 2445 2446 COUNTER_ARRAY_FREE(sc->counters, OVPN_COUNTER_SIZE); 2447 2448 if_free(sc->ifp); 2449 free(sc, M_OVPN); 2450 } 2451 2452 static int 2453 ovpn_clone_destroy(struct if_clone *ifc, struct ifnet *ifp, uint32_t flags) 2454 { 2455 struct ovpn_softc *sc; 2456 int unit; 2457 int i; 2458 int ret __diagused; 2459 2460 sc = ifp->if_softc; 2461 unit = ifp->if_dunit; 2462 2463 OVPN_WLOCK(sc); 2464 2465 if (atomic_load_int(&sc->refcount) > 0) { 2466 OVPN_WUNLOCK(sc); 2467 return (EBUSY); 2468 } 2469 2470 i = 0; 2471 do { 2472 if (sc->peers[i] != NULL) { 2473 ret = _ovpn_del_peer(sc, sc->peers[i]->peerid); 2474 MPASS(ret == 0); 2475 } 2476 i++; 2477 } while (i < OVPN_MAX_PEERS); 2478 2479 ovpn_flush_rxring(sc); 2480 buf_ring_free(sc->rxring, M_OVPN); 2481 buf_ring_free(sc->notifring, M_OVPN); 2482 2483 OVPN_WUNLOCK(sc); 2484 2485 bpfdetach(ifp); 2486 if_detach(ifp); 2487 ifp->if_softc = NULL; 2488 2489 NET_EPOCH_CALL(ovpn_clone_destroy_cb, &sc->epoch_ctx); 2490 2491 if (unit != IF_DUNIT_NONE) 2492 ifc_free_unit(ifc, unit); 2493 2494 NET_EPOCH_DRAIN_CALLBACKS(); 2495 2496 return (0); 2497 } 2498 2499 static void 2500 vnet_ovpn_init(const void *unused __unused) 2501 { 2502 struct if_clone_addreq req = { 2503 .match_f = ovpn_clone_match, 2504 .create_f = ovpn_clone_create, 2505 .destroy_f = ovpn_clone_destroy, 2506 }; 2507 V_ovpn_cloner = ifc_attach_cloner(ovpngroupname, &req); 2508 } 2509 VNET_SYSINIT(vnet_ovpn_init, SI_SUB_PSEUDO, SI_ORDER_ANY, 2510 vnet_ovpn_init, NULL); 2511 2512 static void 2513 vnet_ovpn_uninit(const void *unused __unused) 2514 { 2515 if_clone_detach(V_ovpn_cloner); 2516 } 2517 VNET_SYSUNINIT(vnet_ovpn_uninit, SI_SUB_PSEUDO, SI_ORDER_ANY, 2518 vnet_ovpn_uninit, NULL); 2519 2520 static int 2521 ovpnmodevent(module_t mod, int type, void *data) 2522 { 2523 switch (type) { 2524 case MOD_LOAD: 2525 /* Done in vnet_ovpn_init() */ 2526 break; 2527 case MOD_UNLOAD: 2528 /* Done in vnet_ovpn_uninit() */ 2529 break; 2530 default: 2531 return (EOPNOTSUPP); 2532 } 2533 2534 return (0); 2535 } 2536 2537 static moduledata_t ovpn_mod = { 2538 "if_ovpn", 2539 ovpnmodevent, 2540 0 2541 }; 2542 2543 DECLARE_MODULE(if_ovpn, ovpn_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 2544 MODULE_VERSION(if_ovpn, 1); 2545