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