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 struct sock *sk = (struct sock *)msk; 94 95 list_for_each_entry_safe(entry, tmp, &msk->pm.userspace_pm_local_addr_list, list) { 96 if (mptcp_addresses_equal(&entry->addr, &addr->addr, false)) { 97 /* TODO: a refcount is needed because the entry can 98 * be used multiple times (e.g. fullmesh mode). 99 */ 100 list_del_rcu(&entry->list); 101 sock_kfree_s(sk, entry, sizeof(*entry)); 102 msk->pm.local_addr_used--; 103 return 0; 104 } 105 } 106 107 return -EINVAL; 108 } 109 110 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 111 unsigned int id, 112 u8 *flags, int *ifindex) 113 { 114 struct mptcp_pm_addr_entry *entry, *match = NULL; 115 116 spin_lock_bh(&msk->pm.lock); 117 list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { 118 if (id == entry->addr.id) { 119 match = entry; 120 break; 121 } 122 } 123 spin_unlock_bh(&msk->pm.lock); 124 if (match) { 125 *flags = match->flags; 126 *ifindex = match->ifindex; 127 } 128 129 return 0; 130 } 131 132 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, 133 struct mptcp_addr_info *skc) 134 { 135 struct mptcp_pm_addr_entry *entry = NULL, *e, new_entry; 136 __be16 msk_sport = ((struct inet_sock *) 137 inet_sk((struct sock *)msk))->inet_sport; 138 139 spin_lock_bh(&msk->pm.lock); 140 list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) { 141 if (mptcp_addresses_equal(&e->addr, skc, false)) { 142 entry = e; 143 break; 144 } 145 } 146 spin_unlock_bh(&msk->pm.lock); 147 if (entry) 148 return entry->addr.id; 149 150 memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry)); 151 new_entry.addr = *skc; 152 new_entry.addr.id = 0; 153 new_entry.flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 154 155 if (new_entry.addr.port == msk_sport) 156 new_entry.addr.port = 0; 157 158 return mptcp_userspace_pm_append_new_local_addr(msk, &new_entry, true); 159 } 160 161 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, 162 struct mptcp_addr_info *skc) 163 { 164 struct mptcp_pm_addr_entry *entry; 165 bool backup = false; 166 167 spin_lock_bh(&msk->pm.lock); 168 list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { 169 if (mptcp_addresses_equal(&entry->addr, skc, false)) { 170 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); 171 break; 172 } 173 } 174 spin_unlock_bh(&msk->pm.lock); 175 176 return backup; 177 } 178 179 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info) 180 { 181 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 182 struct nlattr *addr = info->attrs[MPTCP_PM_ATTR_ADDR]; 183 struct mptcp_pm_addr_entry addr_val; 184 struct mptcp_sock *msk; 185 int err = -EINVAL; 186 u32 token_val; 187 188 if (!addr || !token) { 189 GENL_SET_ERR_MSG(info, "missing required inputs"); 190 return err; 191 } 192 193 token_val = nla_get_u32(token); 194 195 msk = mptcp_token_get_sock(sock_net(skb->sk), token_val); 196 if (!msk) { 197 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 198 return err; 199 } 200 201 if (!mptcp_pm_is_userspace(msk)) { 202 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 203 goto announce_err; 204 } 205 206 err = mptcp_pm_parse_entry(addr, info, true, &addr_val); 207 if (err < 0) { 208 GENL_SET_ERR_MSG(info, "error parsing local address"); 209 goto announce_err; 210 } 211 212 if (addr_val.addr.id == 0 || !(addr_val.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 213 GENL_SET_ERR_MSG(info, "invalid addr id or flags"); 214 err = -EINVAL; 215 goto announce_err; 216 } 217 218 err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val, false); 219 if (err < 0) { 220 GENL_SET_ERR_MSG(info, "did not match address and id"); 221 goto announce_err; 222 } 223 224 lock_sock((struct sock *)msk); 225 spin_lock_bh(&msk->pm.lock); 226 227 if (mptcp_pm_alloc_anno_list(msk, &addr_val.addr)) { 228 msk->pm.add_addr_signaled++; 229 mptcp_pm_announce_addr(msk, &addr_val.addr, false); 230 mptcp_pm_nl_addr_send_ack(msk); 231 } 232 233 spin_unlock_bh(&msk->pm.lock); 234 release_sock((struct sock *)msk); 235 236 err = 0; 237 announce_err: 238 sock_put((struct sock *)msk); 239 return err; 240 } 241 242 static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk, 243 struct genl_info *info) 244 { 245 struct mptcp_rm_list list = { .nr = 0 }; 246 struct mptcp_subflow_context *subflow; 247 struct sock *sk = (struct sock *)msk; 248 bool has_id_0 = false; 249 int err = -EINVAL; 250 251 lock_sock(sk); 252 mptcp_for_each_subflow(msk, subflow) { 253 if (subflow->local_id == 0) { 254 has_id_0 = true; 255 break; 256 } 257 } 258 if (!has_id_0) { 259 GENL_SET_ERR_MSG(info, "address with id 0 not found"); 260 goto remove_err; 261 } 262 263 list.ids[list.nr++] = 0; 264 265 spin_lock_bh(&msk->pm.lock); 266 mptcp_pm_remove_addr(msk, &list); 267 spin_unlock_bh(&msk->pm.lock); 268 269 err = 0; 270 271 remove_err: 272 release_sock(sk); 273 return err; 274 } 275 276 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info) 277 { 278 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 279 struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID]; 280 struct mptcp_pm_addr_entry *match = NULL; 281 struct mptcp_pm_addr_entry *entry; 282 struct mptcp_sock *msk; 283 LIST_HEAD(free_list); 284 int err = -EINVAL; 285 u32 token_val; 286 u8 id_val; 287 288 if (!id || !token) { 289 GENL_SET_ERR_MSG(info, "missing required inputs"); 290 return err; 291 } 292 293 id_val = nla_get_u8(id); 294 token_val = nla_get_u32(token); 295 296 msk = mptcp_token_get_sock(sock_net(skb->sk), token_val); 297 if (!msk) { 298 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 299 return err; 300 } 301 302 if (!mptcp_pm_is_userspace(msk)) { 303 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 304 goto remove_err; 305 } 306 307 if (id_val == 0) { 308 err = mptcp_userspace_pm_remove_id_zero_address(msk, info); 309 goto remove_err; 310 } 311 312 lock_sock((struct sock *)msk); 313 314 list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { 315 if (entry->addr.id == id_val) { 316 match = entry; 317 break; 318 } 319 } 320 321 if (!match) { 322 GENL_SET_ERR_MSG(info, "address with specified id not found"); 323 release_sock((struct sock *)msk); 324 goto remove_err; 325 } 326 327 list_move(&match->list, &free_list); 328 329 mptcp_pm_remove_addrs(msk, &free_list); 330 331 release_sock((struct sock *)msk); 332 333 list_for_each_entry_safe(match, entry, &free_list, list) { 334 sock_kfree_s((struct sock *)msk, match, sizeof(*match)); 335 } 336 337 err = 0; 338 remove_err: 339 sock_put((struct sock *)msk); 340 return err; 341 } 342 343 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info) 344 { 345 struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 346 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 347 struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR]; 348 struct mptcp_pm_addr_entry local = { 0 }; 349 struct mptcp_addr_info addr_r; 350 struct mptcp_addr_info addr_l; 351 struct mptcp_sock *msk; 352 int err = -EINVAL; 353 struct sock *sk; 354 u32 token_val; 355 356 if (!laddr || !raddr || !token) { 357 GENL_SET_ERR_MSG(info, "missing required inputs"); 358 return err; 359 } 360 361 token_val = nla_get_u32(token); 362 363 msk = mptcp_token_get_sock(genl_info_net(info), token_val); 364 if (!msk) { 365 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 366 return err; 367 } 368 369 if (!mptcp_pm_is_userspace(msk)) { 370 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 371 goto create_err; 372 } 373 374 err = mptcp_pm_parse_addr(laddr, info, &addr_l); 375 if (err < 0) { 376 NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr"); 377 goto create_err; 378 } 379 380 err = mptcp_pm_parse_addr(raddr, info, &addr_r); 381 if (err < 0) { 382 NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr"); 383 goto create_err; 384 } 385 386 sk = (struct sock *)msk; 387 388 if (!mptcp_pm_addr_families_match(sk, &addr_l, &addr_r)) { 389 GENL_SET_ERR_MSG(info, "families mismatch"); 390 err = -EINVAL; 391 goto create_err; 392 } 393 394 local.addr = addr_l; 395 err = mptcp_userspace_pm_append_new_local_addr(msk, &local, false); 396 if (err < 0) { 397 GENL_SET_ERR_MSG(info, "did not match address and id"); 398 goto create_err; 399 } 400 401 lock_sock(sk); 402 403 err = __mptcp_subflow_connect(sk, &addr_l, &addr_r); 404 405 release_sock(sk); 406 407 spin_lock_bh(&msk->pm.lock); 408 if (err) 409 mptcp_userspace_pm_delete_local_addr(msk, &local); 410 else 411 msk->pm.subflows++; 412 spin_unlock_bh(&msk->pm.lock); 413 414 create_err: 415 sock_put((struct sock *)msk); 416 return err; 417 } 418 419 static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk, 420 const struct mptcp_addr_info *local, 421 const struct mptcp_addr_info *remote) 422 { 423 struct mptcp_subflow_context *subflow; 424 425 if (local->family != remote->family) 426 return NULL; 427 428 mptcp_for_each_subflow(msk, subflow) { 429 const struct inet_sock *issk; 430 struct sock *ssk; 431 432 ssk = mptcp_subflow_tcp_sock(subflow); 433 434 if (local->family != ssk->sk_family) 435 continue; 436 437 issk = inet_sk(ssk); 438 439 switch (ssk->sk_family) { 440 case AF_INET: 441 if (issk->inet_saddr != local->addr.s_addr || 442 issk->inet_daddr != remote->addr.s_addr) 443 continue; 444 break; 445 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 446 case AF_INET6: { 447 const struct ipv6_pinfo *pinfo = inet6_sk(ssk); 448 449 if (!ipv6_addr_equal(&local->addr6, &pinfo->saddr) || 450 !ipv6_addr_equal(&remote->addr6, &ssk->sk_v6_daddr)) 451 continue; 452 break; 453 } 454 #endif 455 default: 456 continue; 457 } 458 459 if (issk->inet_sport == local->port && 460 issk->inet_dport == remote->port) 461 return ssk; 462 } 463 464 return NULL; 465 } 466 467 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info) 468 { 469 struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 470 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 471 struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR]; 472 struct mptcp_addr_info addr_l; 473 struct mptcp_addr_info addr_r; 474 struct mptcp_sock *msk; 475 struct sock *sk, *ssk; 476 int err = -EINVAL; 477 u32 token_val; 478 479 if (!laddr || !raddr || !token) { 480 GENL_SET_ERR_MSG(info, "missing required inputs"); 481 return err; 482 } 483 484 token_val = nla_get_u32(token); 485 486 msk = mptcp_token_get_sock(genl_info_net(info), token_val); 487 if (!msk) { 488 NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); 489 return err; 490 } 491 492 if (!mptcp_pm_is_userspace(msk)) { 493 GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); 494 goto destroy_err; 495 } 496 497 err = mptcp_pm_parse_addr(laddr, info, &addr_l); 498 if (err < 0) { 499 NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr"); 500 goto destroy_err; 501 } 502 503 err = mptcp_pm_parse_addr(raddr, info, &addr_r); 504 if (err < 0) { 505 NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr"); 506 goto destroy_err; 507 } 508 509 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 510 if (addr_l.family == AF_INET && ipv6_addr_v4mapped(&addr_r.addr6)) { 511 ipv6_addr_set_v4mapped(addr_l.addr.s_addr, &addr_l.addr6); 512 addr_l.family = AF_INET6; 513 } 514 if (addr_r.family == AF_INET && ipv6_addr_v4mapped(&addr_l.addr6)) { 515 ipv6_addr_set_v4mapped(addr_r.addr.s_addr, &addr_r.addr6); 516 addr_r.family = AF_INET6; 517 } 518 #endif 519 if (addr_l.family != addr_r.family) { 520 GENL_SET_ERR_MSG(info, "address families do not match"); 521 err = -EINVAL; 522 goto destroy_err; 523 } 524 525 if (!addr_l.port || !addr_r.port) { 526 GENL_SET_ERR_MSG(info, "missing local or remote port"); 527 err = -EINVAL; 528 goto destroy_err; 529 } 530 531 sk = (struct sock *)msk; 532 lock_sock(sk); 533 ssk = mptcp_nl_find_ssk(msk, &addr_l, &addr_r); 534 if (ssk) { 535 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 536 struct mptcp_pm_addr_entry entry = { .addr = addr_l }; 537 538 spin_lock_bh(&msk->pm.lock); 539 mptcp_userspace_pm_delete_local_addr(msk, &entry); 540 spin_unlock_bh(&msk->pm.lock); 541 mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN); 542 mptcp_close_ssk(sk, ssk, subflow); 543 MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW); 544 err = 0; 545 } else { 546 err = -ESRCH; 547 } 548 release_sock(sk); 549 550 destroy_err: 551 sock_put((struct sock *)msk); 552 return err; 553 } 554 555 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 556 struct mptcp_pm_addr_entry *loc, 557 struct mptcp_pm_addr_entry *rem, u8 bkup) 558 { 559 struct mptcp_sock *msk; 560 int ret = -EINVAL; 561 u32 token_val; 562 563 token_val = nla_get_u32(token); 564 565 msk = mptcp_token_get_sock(net, token_val); 566 if (!msk) 567 return ret; 568 569 if (!mptcp_pm_is_userspace(msk)) 570 goto set_flags_err; 571 572 if (loc->addr.family == AF_UNSPEC || 573 rem->addr.family == AF_UNSPEC) 574 goto set_flags_err; 575 576 lock_sock((struct sock *)msk); 577 ret = mptcp_pm_nl_mp_prio_send_ack(msk, &loc->addr, &rem->addr, bkup); 578 release_sock((struct sock *)msk); 579 580 set_flags_err: 581 sock_put((struct sock *)msk); 582 return ret; 583 } 584