1 // SPDX-License-Identifier: GPL-2.0 2 /* Multipath TCP 3 * 4 * Copyright (c) 2022, Intel Corporation. 5 */ 6 7 #include "protocol.h" 8 #include "mib.h" 9 10 void mptcp_free_local_addr_list(struct mptcp_sock *msk) 11 { 12 struct mptcp_pm_addr_entry *entry, *tmp; 13 struct sock *sk = (struct sock *)msk; 14 LIST_HEAD(free_list); 15 16 if (!mptcp_pm_is_userspace(msk)) 17 return; 18 19 spin_lock_bh(&msk->pm.lock); 20 list_splice_init(&msk->pm.userspace_pm_local_addr_list, &free_list); 21 spin_unlock_bh(&msk->pm.lock); 22 23 list_for_each_entry_safe(entry, tmp, &free_list, list) { 24 sock_kfree_s(sk, entry, sizeof(*entry)); 25 } 26 } 27 28 static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk, 29 struct mptcp_pm_addr_entry *entry, 30 bool needs_id) 31 { 32 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 33 struct mptcp_pm_addr_entry *match = NULL; 34 struct sock *sk = (struct sock *)msk; 35 struct mptcp_pm_addr_entry *e; 36 bool addr_match = false; 37 bool id_match = false; 38 int ret = -EINVAL; 39 40 bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 41 42 spin_lock_bh(&msk->pm.lock); 43 list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) { 44 addr_match = mptcp_addresses_equal(&e->addr, &entry->addr, true); 45 if (addr_match && entry->addr.id == 0 && needs_id) 46 entry->addr.id = e->addr.id; 47 id_match = (e->addr.id == entry->addr.id); 48 if (addr_match && id_match) { 49 match = e; 50 break; 51 } else if (addr_match || id_match) { 52 break; 53 } 54 __set_bit(e->addr.id, id_bitmap); 55 } 56 57 if (!match && !addr_match && !id_match) { 58 /* Memory for the entry is allocated from the 59 * sock option buffer. 60 */ 61 e = sock_kmalloc(sk, sizeof(*e), GFP_ATOMIC); 62 if (!e) { 63 ret = -ENOMEM; 64 goto append_err; 65 } 66 67 *e = *entry; 68 if (!e->addr.id && needs_id) 69 e->addr.id = find_next_zero_bit(id_bitmap, 70 MPTCP_PM_MAX_ADDR_ID + 1, 71 1); 72 list_add_tail_rcu(&e->list, &msk->pm.userspace_pm_local_addr_list); 73 msk->pm.local_addr_used++; 74 ret = e->addr.id; 75 } else if (match) { 76 ret = entry->addr.id; 77 } 78 79 append_err: 80 spin_unlock_bh(&msk->pm.lock); 81 return ret; 82 } 83 84 /* If the subflow is closed from the other peer (not via a 85 * subflow destroy command then), we want to keep the entry 86 * not to assign the same ID to another address and to be 87 * able to send RM_ADDR after the removal of the subflow. 88 */ 89 static int mptcp_userspace_pm_delete_local_addr(struct mptcp_sock *msk, 90 struct mptcp_pm_addr_entry *addr) 91 { 92 struct mptcp_pm_addr_entry *entry, *tmp; 93 94 list_for_each_entry_safe(entry, tmp, &msk->pm.userspace_pm_local_addr_list, list) { 95 if (mptcp_addresses_equal(&entry->addr, &addr->addr, false)) { 96 /* TODO: a refcount is needed because the entry can 97 * be used multiple times (e.g. fullmesh mode). 98 */ 99 list_del_rcu(&entry->list); 100 kfree(entry); 101 msk->pm.local_addr_used--; 102 return 0; 103 } 104 } 105 106 return -EINVAL; 107 } 108 109 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 110 unsigned int id, 111 u8 *flags, int *ifindex) 112 { 113 struct mptcp_pm_addr_entry *entry, *match = NULL; 114 115 spin_lock_bh(&msk->pm.lock); 116 list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { 117 if (id == entry->addr.id) { 118 match = entry; 119 break; 120 } 121 } 122 spin_unlock_bh(&msk->pm.lock); 123 if (match) { 124 *flags = match->flags; 125 *ifindex = match->ifindex; 126 } 127 128 return 0; 129 } 130 131 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, 132 struct mptcp_addr_info *skc) 133 { 134 struct mptcp_pm_addr_entry *entry = NULL, *e, new_entry; 135 __be16 msk_sport = ((struct inet_sock *) 136 inet_sk((struct sock *)msk))->inet_sport; 137 138 spin_lock_bh(&msk->pm.lock); 139 list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) { 140 if (mptcp_addresses_equal(&e->addr, skc, false)) { 141 entry = e; 142 break; 143 } 144 } 145 spin_unlock_bh(&msk->pm.lock); 146 if (entry) 147 return entry->addr.id; 148 149 memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry)); 150 new_entry.addr = *skc; 151 new_entry.addr.id = 0; 152 new_entry.flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 153 154 if (new_entry.addr.port == msk_sport) 155 new_entry.addr.port = 0; 156 157 return mptcp_userspace_pm_append_new_local_addr(msk, &new_entry, true); 158 } 159 160 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, 161 struct mptcp_addr_info *skc) 162 { 163 struct mptcp_pm_addr_entry *entry; 164 bool backup = false; 165 166 spin_lock_bh(&msk->pm.lock); 167 list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { 168 if (mptcp_addresses_equal(&entry->addr, skc, false)) { 169 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); 170 break; 171 } 172 } 173 spin_unlock_bh(&msk->pm.lock); 174 175 return backup; 176 } 177 178 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info) 179 { 180 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 181 struct nlattr *addr = info->attrs[MPTCP_PM_ATTR_ADDR]; 182 struct mptcp_pm_addr_entry addr_val; 183 struct mptcp_sock *msk; 184 int err = -EINVAL; 185 u32 token_val; 186 187 if (!addr || !token) { 188 GENL_SET_ERR_MSG(info, "missing required inputs"); 189 return err; 190 } 191 192 token_val = nla_get_u32(token); 193 194 msk = mptcp_token_get_sock(sock_net(skb->sk), token_val); 195 if (!msk) { 196 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 197 return err; 198 } 199 200 if (!mptcp_pm_is_userspace(msk)) { 201 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 202 goto announce_err; 203 } 204 205 err = mptcp_pm_parse_entry(addr, info, true, &addr_val); 206 if (err < 0) { 207 GENL_SET_ERR_MSG(info, "error parsing local address"); 208 goto announce_err; 209 } 210 211 if (addr_val.addr.id == 0 || !(addr_val.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 212 GENL_SET_ERR_MSG(info, "invalid addr id or flags"); 213 err = -EINVAL; 214 goto announce_err; 215 } 216 217 err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val, false); 218 if (err < 0) { 219 GENL_SET_ERR_MSG(info, "did not match address and id"); 220 goto announce_err; 221 } 222 223 lock_sock((struct sock *)msk); 224 spin_lock_bh(&msk->pm.lock); 225 226 if (mptcp_pm_alloc_anno_list(msk, &addr_val.addr)) { 227 msk->pm.add_addr_signaled++; 228 mptcp_pm_announce_addr(msk, &addr_val.addr, false); 229 mptcp_pm_nl_addr_send_ack(msk); 230 } 231 232 spin_unlock_bh(&msk->pm.lock); 233 release_sock((struct sock *)msk); 234 235 err = 0; 236 announce_err: 237 sock_put((struct sock *)msk); 238 return err; 239 } 240 241 static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk, 242 struct genl_info *info) 243 { 244 struct mptcp_rm_list list = { .nr = 0 }; 245 struct mptcp_subflow_context *subflow; 246 struct sock *sk = (struct sock *)msk; 247 bool has_id_0 = false; 248 int err = -EINVAL; 249 250 lock_sock(sk); 251 mptcp_for_each_subflow(msk, subflow) { 252 if (subflow->local_id == 0) { 253 has_id_0 = true; 254 break; 255 } 256 } 257 if (!has_id_0) { 258 GENL_SET_ERR_MSG(info, "address with id 0 not found"); 259 goto remove_err; 260 } 261 262 list.ids[list.nr++] = 0; 263 264 spin_lock_bh(&msk->pm.lock); 265 mptcp_pm_remove_addr(msk, &list); 266 spin_unlock_bh(&msk->pm.lock); 267 268 err = 0; 269 270 remove_err: 271 release_sock(sk); 272 return err; 273 } 274 275 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info) 276 { 277 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 278 struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID]; 279 struct mptcp_pm_addr_entry *match = NULL; 280 struct mptcp_pm_addr_entry *entry; 281 struct mptcp_sock *msk; 282 LIST_HEAD(free_list); 283 int err = -EINVAL; 284 u32 token_val; 285 u8 id_val; 286 287 if (!id || !token) { 288 GENL_SET_ERR_MSG(info, "missing required inputs"); 289 return err; 290 } 291 292 id_val = nla_get_u8(id); 293 token_val = nla_get_u32(token); 294 295 msk = mptcp_token_get_sock(sock_net(skb->sk), token_val); 296 if (!msk) { 297 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 298 return err; 299 } 300 301 if (!mptcp_pm_is_userspace(msk)) { 302 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 303 goto remove_err; 304 } 305 306 if (id_val == 0) { 307 err = mptcp_userspace_pm_remove_id_zero_address(msk, info); 308 goto remove_err; 309 } 310 311 lock_sock((struct sock *)msk); 312 313 list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { 314 if (entry->addr.id == id_val) { 315 match = entry; 316 break; 317 } 318 } 319 320 if (!match) { 321 GENL_SET_ERR_MSG(info, "address with specified id not found"); 322 release_sock((struct sock *)msk); 323 goto remove_err; 324 } 325 326 list_move(&match->list, &free_list); 327 328 mptcp_pm_remove_addrs(msk, &free_list); 329 330 release_sock((struct sock *)msk); 331 332 list_for_each_entry_safe(match, entry, &free_list, list) { 333 sock_kfree_s((struct sock *)msk, match, sizeof(*match)); 334 } 335 336 err = 0; 337 remove_err: 338 sock_put((struct sock *)msk); 339 return err; 340 } 341 342 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info) 343 { 344 struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 345 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 346 struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR]; 347 struct mptcp_pm_addr_entry local = { 0 }; 348 struct mptcp_addr_info addr_r; 349 struct mptcp_addr_info addr_l; 350 struct mptcp_sock *msk; 351 int err = -EINVAL; 352 struct sock *sk; 353 u32 token_val; 354 355 if (!laddr || !raddr || !token) { 356 GENL_SET_ERR_MSG(info, "missing required inputs"); 357 return err; 358 } 359 360 token_val = nla_get_u32(token); 361 362 msk = mptcp_token_get_sock(genl_info_net(info), token_val); 363 if (!msk) { 364 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 365 return err; 366 } 367 368 if (!mptcp_pm_is_userspace(msk)) { 369 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 370 goto create_err; 371 } 372 373 err = mptcp_pm_parse_addr(laddr, info, &addr_l); 374 if (err < 0) { 375 NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr"); 376 goto create_err; 377 } 378 379 err = mptcp_pm_parse_addr(raddr, info, &addr_r); 380 if (err < 0) { 381 NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr"); 382 goto create_err; 383 } 384 385 sk = (struct sock *)msk; 386 387 if (!mptcp_pm_addr_families_match(sk, &addr_l, &addr_r)) { 388 GENL_SET_ERR_MSG(info, "families mismatch"); 389 err = -EINVAL; 390 goto create_err; 391 } 392 393 local.addr = addr_l; 394 err = mptcp_userspace_pm_append_new_local_addr(msk, &local, false); 395 if (err < 0) { 396 GENL_SET_ERR_MSG(info, "did not match address and id"); 397 goto create_err; 398 } 399 400 lock_sock(sk); 401 402 err = __mptcp_subflow_connect(sk, &addr_l, &addr_r); 403 404 release_sock(sk); 405 406 spin_lock_bh(&msk->pm.lock); 407 if (err) 408 mptcp_userspace_pm_delete_local_addr(msk, &local); 409 else 410 msk->pm.subflows++; 411 spin_unlock_bh(&msk->pm.lock); 412 413 create_err: 414 sock_put((struct sock *)msk); 415 return err; 416 } 417 418 static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk, 419 const struct mptcp_addr_info *local, 420 const struct mptcp_addr_info *remote) 421 { 422 struct mptcp_subflow_context *subflow; 423 424 if (local->family != remote->family) 425 return NULL; 426 427 mptcp_for_each_subflow(msk, subflow) { 428 const struct inet_sock *issk; 429 struct sock *ssk; 430 431 ssk = mptcp_subflow_tcp_sock(subflow); 432 433 if (local->family != ssk->sk_family) 434 continue; 435 436 issk = inet_sk(ssk); 437 438 switch (ssk->sk_family) { 439 case AF_INET: 440 if (issk->inet_saddr != local->addr.s_addr || 441 issk->inet_daddr != remote->addr.s_addr) 442 continue; 443 break; 444 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 445 case AF_INET6: { 446 const struct ipv6_pinfo *pinfo = inet6_sk(ssk); 447 448 if (!ipv6_addr_equal(&local->addr6, &pinfo->saddr) || 449 !ipv6_addr_equal(&remote->addr6, &ssk->sk_v6_daddr)) 450 continue; 451 break; 452 } 453 #endif 454 default: 455 continue; 456 } 457 458 if (issk->inet_sport == local->port && 459 issk->inet_dport == remote->port) 460 return ssk; 461 } 462 463 return NULL; 464 } 465 466 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info) 467 { 468 struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 469 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 470 struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR]; 471 struct mptcp_addr_info addr_l; 472 struct mptcp_addr_info addr_r; 473 struct mptcp_sock *msk; 474 struct sock *sk, *ssk; 475 int err = -EINVAL; 476 u32 token_val; 477 478 if (!laddr || !raddr || !token) { 479 GENL_SET_ERR_MSG(info, "missing required inputs"); 480 return err; 481 } 482 483 token_val = nla_get_u32(token); 484 485 msk = mptcp_token_get_sock(genl_info_net(info), token_val); 486 if (!msk) { 487 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 488 return err; 489 } 490 491 if (!mptcp_pm_is_userspace(msk)) { 492 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 493 goto destroy_err; 494 } 495 496 err = mptcp_pm_parse_addr(laddr, info, &addr_l); 497 if (err < 0) { 498 NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr"); 499 goto destroy_err; 500 } 501 502 err = mptcp_pm_parse_addr(raddr, info, &addr_r); 503 if (err < 0) { 504 NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr"); 505 goto destroy_err; 506 } 507 508 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 509 if (addr_l.family == AF_INET && ipv6_addr_v4mapped(&addr_r.addr6)) { 510 ipv6_addr_set_v4mapped(addr_l.addr.s_addr, &addr_l.addr6); 511 addr_l.family = AF_INET6; 512 } 513 if (addr_r.family == AF_INET && ipv6_addr_v4mapped(&addr_l.addr6)) { 514 ipv6_addr_set_v4mapped(addr_r.addr.s_addr, &addr_r.addr6); 515 addr_r.family = AF_INET6; 516 } 517 #endif 518 if (addr_l.family != addr_r.family) { 519 GENL_SET_ERR_MSG(info, "address families do not match"); 520 err = -EINVAL; 521 goto destroy_err; 522 } 523 524 if (!addr_l.port || !addr_r.port) { 525 GENL_SET_ERR_MSG(info, "missing local or remote port"); 526 err = -EINVAL; 527 goto destroy_err; 528 } 529 530 sk = (struct sock *)msk; 531 lock_sock(sk); 532 ssk = mptcp_nl_find_ssk(msk, &addr_l, &addr_r); 533 if (ssk) { 534 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 535 struct mptcp_pm_addr_entry entry = { .addr = addr_l }; 536 537 spin_lock_bh(&msk->pm.lock); 538 mptcp_userspace_pm_delete_local_addr(msk, &entry); 539 spin_unlock_bh(&msk->pm.lock); 540 mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN); 541 mptcp_close_ssk(sk, ssk, subflow); 542 MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW); 543 err = 0; 544 } else { 545 err = -ESRCH; 546 } 547 release_sock(sk); 548 549 destroy_err: 550 sock_put((struct sock *)msk); 551 return err; 552 } 553 554 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 555 struct mptcp_pm_addr_entry *loc, 556 struct mptcp_pm_addr_entry *rem, u8 bkup) 557 { 558 struct mptcp_sock *msk; 559 int ret = -EINVAL; 560 u32 token_val; 561 562 token_val = nla_get_u32(token); 563 564 msk = mptcp_token_get_sock(net, token_val); 565 if (!msk) 566 return ret; 567 568 if (!mptcp_pm_is_userspace(msk)) 569 goto set_flags_err; 570 571 if (loc->addr.family == AF_UNSPEC || 572 rem->addr.family == AF_UNSPEC) 573 goto set_flags_err; 574 575 lock_sock((struct sock *)msk); 576 ret = mptcp_pm_nl_mp_prio_send_ack(msk, &loc->addr, &rem->addr, bkup); 577 release_sock((struct sock *)msk); 578 579 set_flags_err: 580 sock_put((struct sock *)msk); 581 return ret; 582 } 583