1// SPDX-License-Identifier: GPL-2.0 2/* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */ 3 4#include <linux/bpf.h> 5#include <linux/btf_ids.h> 6#include <linux/filter.h> 7#include <linux/errno.h> 8#include <linux/file.h> 9#include <linux/net.h> 10#include <linux/workqueue.h> 11#include <linux/skmsg.h> 12#include <linux/list.h> 13#include <linux/jhash.h> 14#include <linux/sock_diag.h> 15#include <net/udp.h> 16 17struct bpf_stab { 18 struct bpf_map map; 19 struct sock **sks; 20 struct sk_psock_progs progs; 21 spinlock_t lock; 22}; 23 24#define SOCK_CREATE_FLAG_MASK \ 25 (BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY) 26 27static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog, 28 struct bpf_prog *old, u32 which); 29static struct sk_psock_progs *sock_map_progs(struct bpf_map *map); 30 31static struct bpf_map *sock_map_alloc(union bpf_attr *attr) 32{ 33 struct bpf_stab *stab; 34 35 if (attr->max_entries == 0 || 36 attr->key_size != 4 || 37 (attr->value_size != sizeof(u32) && 38 attr->value_size != sizeof(u64)) || 39 attr->map_flags & ~SOCK_CREATE_FLAG_MASK) 40 return ERR_PTR(-EINVAL); 41 42 stab = bpf_map_area_alloc(sizeof(*stab), NUMA_NO_NODE); 43 if (!stab) 44 return ERR_PTR(-ENOMEM); 45 46 bpf_map_init_from_attr(&stab->map, attr); 47 spin_lock_init(&stab->lock); 48 49 stab->sks = bpf_map_area_alloc((u64) stab->map.max_entries * 50 sizeof(struct sock *), 51 stab->map.numa_node); 52 if (!stab->sks) { 53 bpf_map_area_free(stab); 54 return ERR_PTR(-ENOMEM); 55 } 56 57 return &stab->map; 58} 59 60int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog) 61{ 62 u32 ufd = attr->target_fd; 63 struct bpf_map *map; 64 struct fd f; 65 int ret; 66 67 if (attr->attach_flags || attr->replace_bpf_fd) 68 return -EINVAL; 69 70 f = fdget(ufd); 71 map = __bpf_map_get(f); 72 if (IS_ERR(map)) 73 return PTR_ERR(map); 74 ret = sock_map_prog_update(map, prog, NULL, attr->attach_type); 75 fdput(f); 76 return ret; 77} 78 79int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype) 80{ 81 u32 ufd = attr->target_fd; 82 struct bpf_prog *prog; 83 struct bpf_map *map; 84 struct fd f; 85 int ret; 86 87 if (attr->attach_flags || attr->replace_bpf_fd) 88 return -EINVAL; 89 90 f = fdget(ufd); 91 map = __bpf_map_get(f); 92 if (IS_ERR(map)) 93 return PTR_ERR(map); 94 95 prog = bpf_prog_get(attr->attach_bpf_fd); 96 if (IS_ERR(prog)) { 97 ret = PTR_ERR(prog); 98 goto put_map; 99 } 100 101 if (prog->type != ptype) { 102 ret = -EINVAL; 103 goto put_prog; 104 } 105 106 ret = sock_map_prog_update(map, NULL, prog, attr->attach_type); 107put_prog: 108 bpf_prog_put(prog); 109put_map: 110 fdput(f); 111 return ret; 112} 113 114static void sock_map_sk_acquire(struct sock *sk) 115 __acquires(&sk->sk_lock.slock) 116{ 117 lock_sock(sk); 118 rcu_read_lock(); 119} 120 121static void sock_map_sk_release(struct sock *sk) 122 __releases(&sk->sk_lock.slock) 123{ 124 rcu_read_unlock(); 125 release_sock(sk); 126} 127 128static void sock_map_add_link(struct sk_psock *psock, 129 struct sk_psock_link *link, 130 struct bpf_map *map, void *link_raw) 131{ 132 link->link_raw = link_raw; 133 link->map = map; 134 spin_lock_bh(&psock->link_lock); 135 list_add_tail(&link->list, &psock->link); 136 spin_unlock_bh(&psock->link_lock); 137} 138 139static void sock_map_del_link(struct sock *sk, 140 struct sk_psock *psock, void *link_raw) 141{ 142 bool strp_stop = false, verdict_stop = false; 143 struct sk_psock_link *link, *tmp; 144 145 spin_lock_bh(&psock->link_lock); 146 list_for_each_entry_safe(link, tmp, &psock->link, list) { 147 if (link->link_raw == link_raw) { 148 struct bpf_map *map = link->map; 149 struct sk_psock_progs *progs = sock_map_progs(map); 150 151 if (psock->saved_data_ready && progs->stream_parser) 152 strp_stop = true; 153 if (psock->saved_data_ready && progs->stream_verdict) 154 verdict_stop = true; 155 if (psock->saved_data_ready && progs->skb_verdict) 156 verdict_stop = true; 157 list_del(&link->list); 158 sk_psock_free_link(link); 159 } 160 } 161 spin_unlock_bh(&psock->link_lock); 162 if (strp_stop || verdict_stop) { 163 write_lock_bh(&sk->sk_callback_lock); 164 if (strp_stop) 165 sk_psock_stop_strp(sk, psock); 166 if (verdict_stop) 167 sk_psock_stop_verdict(sk, psock); 168 169 if (psock->psock_update_sk_prot) 170 psock->psock_update_sk_prot(sk, psock, false); 171 write_unlock_bh(&sk->sk_callback_lock); 172 } 173} 174 175static void sock_map_unref(struct sock *sk, void *link_raw) 176{ 177 struct sk_psock *psock = sk_psock(sk); 178 179 if (likely(psock)) { 180 sock_map_del_link(sk, psock, link_raw); 181 sk_psock_put(sk, psock); 182 } 183} 184 185static int sock_map_init_proto(struct sock *sk, struct sk_psock *psock) 186{ 187 if (!sk->sk_prot->psock_update_sk_prot) 188 return -EINVAL; 189 psock->psock_update_sk_prot = sk->sk_prot->psock_update_sk_prot; 190 return sk->sk_prot->psock_update_sk_prot(sk, psock, false); 191} 192 193static struct sk_psock *sock_map_psock_get_checked(struct sock *sk) 194{ 195 struct sk_psock *psock; 196 197 rcu_read_lock(); 198 psock = sk_psock(sk); 199 if (psock) { 200 if (sk->sk_prot->close != sock_map_close) { 201 psock = ERR_PTR(-EBUSY); 202 goto out; 203 } 204 205 if (!refcount_inc_not_zero(&psock->refcnt)) 206 psock = ERR_PTR(-EBUSY); 207 } 208out: 209 rcu_read_unlock(); 210 return psock; 211} 212 213static int sock_map_link(struct bpf_map *map, struct sock *sk) 214{ 215 struct sk_psock_progs *progs = sock_map_progs(map); 216 struct bpf_prog *stream_verdict = NULL; 217 struct bpf_prog *stream_parser = NULL; 218 struct bpf_prog *skb_verdict = NULL; 219 struct bpf_prog *msg_parser = NULL; 220 struct sk_psock *psock; 221 int ret; 222 223 stream_verdict = READ_ONCE(progs->stream_verdict); 224 if (stream_verdict) { 225 stream_verdict = bpf_prog_inc_not_zero(stream_verdict); 226 if (IS_ERR(stream_verdict)) 227 return PTR_ERR(stream_verdict); 228 } 229 230 stream_parser = READ_ONCE(progs->stream_parser); 231 if (stream_parser) { 232 stream_parser = bpf_prog_inc_not_zero(stream_parser); 233 if (IS_ERR(stream_parser)) { 234 ret = PTR_ERR(stream_parser); 235 goto out_put_stream_verdict; 236 } 237 } 238 239 msg_parser = READ_ONCE(progs->msg_parser); 240 if (msg_parser) { 241 msg_parser = bpf_prog_inc_not_zero(msg_parser); 242 if (IS_ERR(msg_parser)) { 243 ret = PTR_ERR(msg_parser); 244 goto out_put_stream_parser; 245 } 246 } 247 248 skb_verdict = READ_ONCE(progs->skb_verdict); 249 if (skb_verdict) { 250 skb_verdict = bpf_prog_inc_not_zero(skb_verdict); 251 if (IS_ERR(skb_verdict)) { 252 ret = PTR_ERR(skb_verdict); 253 goto out_put_msg_parser; 254 } 255 } 256 257 psock = sock_map_psock_get_checked(sk); 258 if (IS_ERR(psock)) { 259 ret = PTR_ERR(psock); 260 goto out_progs; 261 } 262 263 if (psock) { 264 if ((msg_parser && READ_ONCE(psock->progs.msg_parser)) || 265 (stream_parser && READ_ONCE(psock->progs.stream_parser)) || 266 (skb_verdict && READ_ONCE(psock->progs.skb_verdict)) || 267 (skb_verdict && READ_ONCE(psock->progs.stream_verdict)) || 268 (stream_verdict && READ_ONCE(psock->progs.skb_verdict)) || 269 (stream_verdict && READ_ONCE(psock->progs.stream_verdict))) { 270 sk_psock_put(sk, psock); 271 ret = -EBUSY; 272 goto out_progs; 273 } 274 } else { 275 psock = sk_psock_init(sk, map->numa_node); 276 if (IS_ERR(psock)) { 277 ret = PTR_ERR(psock); 278 goto out_progs; 279 } 280 } 281 282 if (msg_parser) 283 psock_set_prog(&psock->progs.msg_parser, msg_parser); 284 if (stream_parser) 285 psock_set_prog(&psock->progs.stream_parser, stream_parser); 286 if (stream_verdict) 287 psock_set_prog(&psock->progs.stream_verdict, stream_verdict); 288 if (skb_verdict) 289 psock_set_prog(&psock->progs.skb_verdict, skb_verdict); 290 291 /* msg_* and stream_* programs references tracked in psock after this 292 * point. Reference dec and cleanup will occur through psock destructor 293 */ 294 ret = sock_map_init_proto(sk, psock); 295 if (ret < 0) { 296 sk_psock_put(sk, psock); 297 goto out; 298 } 299 300 write_lock_bh(&sk->sk_callback_lock); 301 if (stream_parser && stream_verdict && !psock->saved_data_ready) { 302 ret = sk_psock_init_strp(sk, psock); 303 if (ret) { 304 write_unlock_bh(&sk->sk_callback_lock); 305 sk_psock_put(sk, psock); 306 goto out; 307 } 308 sk_psock_start_strp(sk, psock); 309 } else if (!stream_parser && stream_verdict && !psock->saved_data_ready) { 310 sk_psock_start_verdict(sk,psock); 311 } else if (!stream_verdict && skb_verdict && !psock->saved_data_ready) { 312 sk_psock_start_verdict(sk, psock); 313 } 314 write_unlock_bh(&sk->sk_callback_lock); 315 return 0; 316out_progs: 317 if (skb_verdict) 318 bpf_prog_put(skb_verdict); 319out_put_msg_parser: 320 if (msg_parser) 321 bpf_prog_put(msg_parser); 322out_put_stream_parser: 323 if (stream_parser) 324 bpf_prog_put(stream_parser); 325out_put_stream_verdict: 326 if (stream_verdict) 327 bpf_prog_put(stream_verdict); 328out: 329 return ret; 330} 331 332static void sock_map_free(struct bpf_map *map) 333{ 334 struct bpf_stab *stab = container_of(map, struct bpf_stab, map); 335 int i; 336 337 /* After the sync no updates or deletes will be in-flight so it 338 * is safe to walk map and remove entries without risking a race 339 * in EEXIST update case. 340 */ 341 synchronize_rcu(); 342 for (i = 0; i < stab->map.max_entries; i++) { 343 struct sock **psk = &stab->sks[i]; 344 struct sock *sk; 345 346 sk = xchg(psk, NULL); 347 if (sk) { 348 sock_hold(sk); 349 lock_sock(sk); 350 rcu_read_lock(); 351 sock_map_unref(sk, psk); 352 rcu_read_unlock(); 353 release_sock(sk); 354 sock_put(sk); 355 } 356 } 357 358 /* wait for psock readers accessing its map link */ 359 synchronize_rcu(); 360 361 bpf_map_area_free(stab->sks); 362 bpf_map_area_free(stab); 363} 364 365static void sock_map_release_progs(struct bpf_map *map) 366{ 367 psock_progs_drop(&container_of(map, struct bpf_stab, map)->progs); 368} 369 370static struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key) 371{ 372 struct bpf_stab *stab = container_of(map, struct bpf_stab, map); 373 374 WARN_ON_ONCE(!rcu_read_lock_held()); 375 376 if (unlikely(key >= map->max_entries)) 377 return NULL; 378 return READ_ONCE(stab->sks[key]); 379} 380 381static void *sock_map_lookup(struct bpf_map *map, void *key) 382{ 383 struct sock *sk; 384 385 sk = __sock_map_lookup_elem(map, *(u32 *)key); 386 if (!sk) 387 return NULL; 388 if (sk_is_refcounted(sk) && !refcount_inc_not_zero(&sk->sk_refcnt)) 389 return NULL; 390 return sk; 391} 392 393static void *sock_map_lookup_sys(struct bpf_map *map, void *key) 394{ 395 struct sock *sk; 396 397 if (map->value_size != sizeof(u64)) 398 return ERR_PTR(-ENOSPC); 399 400 sk = __sock_map_lookup_elem(map, *(u32 *)key); 401 if (!sk) 402 return ERR_PTR(-ENOENT); 403 404 __sock_gen_cookie(sk); 405 return &sk->sk_cookie; 406} 407 408static int __sock_map_delete(struct bpf_stab *stab, struct sock *sk_test, 409 struct sock **psk) 410{ 411 struct sock *sk; 412 int err = 0; 413 414 spin_lock_bh(&stab->lock); 415 sk = *psk; 416 if (!sk_test || sk_test == sk) 417 sk = xchg(psk, NULL); 418 419 if (likely(sk)) 420 sock_map_unref(sk, psk); 421 else 422 err = -EINVAL; 423 424 spin_unlock_bh(&stab->lock); 425 return err; 426} 427 428static void sock_map_delete_from_link(struct bpf_map *map, struct sock *sk, 429 void *link_raw) 430{ 431 struct bpf_stab *stab = container_of(map, struct bpf_stab, map); 432 433 __sock_map_delete(stab, sk, link_raw); 434} 435 436static long sock_map_delete_elem(struct bpf_map *map, void *key) 437{ 438 struct bpf_stab *stab = container_of(map, struct bpf_stab, map); 439 u32 i = *(u32 *)key; 440 struct sock **psk; 441 442 if (unlikely(i >= map->max_entries)) 443 return -EINVAL; 444 445 psk = &stab->sks[i]; 446 return __sock_map_delete(stab, NULL, psk); 447} 448 449static int sock_map_get_next_key(struct bpf_map *map, void *key, void *next) 450{ 451 struct bpf_stab *stab = container_of(map, struct bpf_stab, map); 452 u32 i = key ? *(u32 *)key : U32_MAX; 453 u32 *key_next = next; 454 455 if (i == stab->map.max_entries - 1) 456 return -ENOENT; 457 if (i >= stab->map.max_entries) 458 *key_next = 0; 459 else 460 *key_next = i + 1; 461 return 0; 462} 463 464static int sock_map_update_common(struct bpf_map *map, u32 idx, 465 struct sock *sk, u64 flags) 466{ 467 struct bpf_stab *stab = container_of(map, struct bpf_stab, map); 468 struct sk_psock_link *link; 469 struct sk_psock *psock; 470 struct sock *osk; 471 int ret; 472 473 WARN_ON_ONCE(!rcu_read_lock_held()); 474 if (unlikely(flags > BPF_EXIST)) 475 return -EINVAL; 476 if (unlikely(idx >= map->max_entries)) 477 return -E2BIG; 478 479 link = sk_psock_init_link(); 480 if (!link) 481 return -ENOMEM; 482 483 ret = sock_map_link(map, sk); 484 if (ret < 0) 485 goto out_free; 486 487 psock = sk_psock(sk); 488 WARN_ON_ONCE(!psock); 489 490 spin_lock_bh(&stab->lock); 491 osk = stab->sks[idx]; 492 if (osk && flags == BPF_NOEXIST) { 493 ret = -EEXIST; 494 goto out_unlock; 495 } else if (!osk && flags == BPF_EXIST) { 496 ret = -ENOENT; 497 goto out_unlock; 498 } 499 500 sock_map_add_link(psock, link, map, &stab->sks[idx]); 501 stab->sks[idx] = sk; 502 if (osk) 503 sock_map_unref(osk, &stab->sks[idx]); 504 spin_unlock_bh(&stab->lock); 505 return 0; 506out_unlock: 507 spin_unlock_bh(&stab->lock); 508 if (psock) 509 sk_psock_put(sk, psock); 510out_free: 511 sk_psock_free_link(link); 512 return ret; 513} 514 515static bool sock_map_op_okay(const struct bpf_sock_ops_kern *ops) 516{ 517 return ops->op == BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB || 518 ops->op == BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB || 519 ops->op == BPF_SOCK_OPS_TCP_LISTEN_CB; 520} 521 522static bool sock_map_redirect_allowed(const struct sock *sk) 523{ 524 if (sk_is_tcp(sk)) 525 return sk->sk_state != TCP_LISTEN; 526 else 527 return sk->sk_state == TCP_ESTABLISHED; 528} 529 530static bool sock_map_sk_is_suitable(const struct sock *sk) 531{ 532 return !!sk->sk_prot->psock_update_sk_prot; 533} 534 535static bool sock_map_sk_state_allowed(const struct sock *sk) 536{ 537 if (sk_is_tcp(sk)) 538 return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_LISTEN); 539 if (sk_is_stream_unix(sk)) 540 return (1 << sk->sk_state) & TCPF_ESTABLISHED; 541 return true; 542} 543 544static int sock_hash_update_common(struct bpf_map *map, void *key, 545 struct sock *sk, u64 flags); 546 547int sock_map_update_elem_sys(struct bpf_map *map, void *key, void *value, 548 u64 flags) 549{ 550 struct socket *sock; 551 struct sock *sk; 552 int ret; 553 u64 ufd; 554 555 if (map->value_size == sizeof(u64)) 556 ufd = *(u64 *)value; 557 else 558 ufd = *(u32 *)value; 559 if (ufd > S32_MAX) 560 return -EINVAL; 561 562 sock = sockfd_lookup(ufd, &ret); 563 if (!sock) 564 return ret; 565 sk = sock->sk; 566 if (!sk) { 567 ret = -EINVAL; 568 goto out; 569 } 570 if (!sock_map_sk_is_suitable(sk)) { 571 ret = -EOPNOTSUPP; 572 goto out; 573 } 574 575 sock_map_sk_acquire(sk); 576 if (!sock_map_sk_state_allowed(sk)) 577 ret = -EOPNOTSUPP; 578 else if (map->map_type == BPF_MAP_TYPE_SOCKMAP) 579 ret = sock_map_update_common(map, *(u32 *)key, sk, flags); 580 else 581 ret = sock_hash_update_common(map, key, sk, flags); 582 sock_map_sk_release(sk); 583out: 584 sockfd_put(sock); 585 return ret; 586} 587 588static long sock_map_update_elem(struct bpf_map *map, void *key, 589 void *value, u64 flags) 590{ 591 struct sock *sk = (struct sock *)value; 592 int ret; 593 594 if (unlikely(!sk || !sk_fullsock(sk))) 595 return -EINVAL; 596 597 if (!sock_map_sk_is_suitable(sk)) 598 return -EOPNOTSUPP; 599 600 local_bh_disable(); 601 bh_lock_sock(sk); 602 if (!sock_map_sk_state_allowed(sk)) 603 ret = -EOPNOTSUPP; 604 else if (map->map_type == BPF_MAP_TYPE_SOCKMAP) 605 ret = sock_map_update_common(map, *(u32 *)key, sk, flags); 606 else 607 ret = sock_hash_update_common(map, key, sk, flags); 608 bh_unlock_sock(sk); 609 local_bh_enable(); 610 return ret; 611} 612 613BPF_CALL_4(bpf_sock_map_update, struct bpf_sock_ops_kern *, sops, 614 struct bpf_map *, map, void *, key, u64, flags) 615{ 616 WARN_ON_ONCE(!rcu_read_lock_held()); 617 618 if (likely(sock_map_sk_is_suitable(sops->sk) && 619 sock_map_op_okay(sops))) 620 return sock_map_update_common(map, *(u32 *)key, sops->sk, 621 flags); 622 return -EOPNOTSUPP; 623} 624 625const struct bpf_func_proto bpf_sock_map_update_proto = { 626 .func = bpf_sock_map_update, 627 .gpl_only = false, 628 .pkt_access = true, 629 .ret_type = RET_INTEGER, 630 .arg1_type = ARG_PTR_TO_CTX, 631 .arg2_type = ARG_CONST_MAP_PTR, 632 .arg3_type = ARG_PTR_TO_MAP_KEY, 633 .arg4_type = ARG_ANYTHING, 634}; 635 636BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb, 637 struct bpf_map *, map, u32, key, u64, flags) 638{ 639 struct sock *sk; 640 641 if (unlikely(flags & ~(BPF_F_INGRESS))) 642 return SK_DROP; 643 644 sk = __sock_map_lookup_elem(map, key); 645 if (unlikely(!sk || !sock_map_redirect_allowed(sk))) 646 return SK_DROP; 647 648 skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS); 649 return SK_PASS; 650} 651 652const struct bpf_func_proto bpf_sk_redirect_map_proto = { 653 .func = bpf_sk_redirect_map, 654 .gpl_only = false, 655 .ret_type = RET_INTEGER, 656 .arg1_type = ARG_PTR_TO_CTX, 657 .arg2_type = ARG_CONST_MAP_PTR, 658 .arg3_type = ARG_ANYTHING, 659 .arg4_type = ARG_ANYTHING, 660}; 661 662BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg *, msg, 663 struct bpf_map *, map, u32, key, u64, flags) 664{ 665 struct sock *sk; 666 667 if (unlikely(flags & ~(BPF_F_INGRESS))) 668 return SK_DROP; 669 670 sk = __sock_map_lookup_elem(map, key); 671 if (unlikely(!sk || !sock_map_redirect_allowed(sk))) 672 return SK_DROP; 673 if (!(flags & BPF_F_INGRESS) && !sk_is_tcp(sk)) 674 return SK_DROP; 675 676 msg->flags = flags; 677 msg->sk_redir = sk; 678 return SK_PASS; 679} 680 681const struct bpf_func_proto bpf_msg_redirect_map_proto = { 682 .func = bpf_msg_redirect_map, 683 .gpl_only = false, 684 .ret_type = RET_INTEGER, 685 .arg1_type = ARG_PTR_TO_CTX, 686 .arg2_type = ARG_CONST_MAP_PTR, 687 .arg3_type = ARG_ANYTHING, 688 .arg4_type = ARG_ANYTHING, 689}; 690 691struct sock_map_seq_info { 692 struct bpf_map *map; 693 struct sock *sk; 694 u32 index; 695}; 696 697struct bpf_iter__sockmap { 698 __bpf_md_ptr(struct bpf_iter_meta *, meta); 699 __bpf_md_ptr(struct bpf_map *, map); 700 __bpf_md_ptr(void *, key); 701 __bpf_md_ptr(struct sock *, sk); 702}; 703 704DEFINE_BPF_ITER_FUNC(sockmap, struct bpf_iter_meta *meta, 705 struct bpf_map *map, void *key, 706 struct sock *sk) 707 708static void *sock_map_seq_lookup_elem(struct sock_map_seq_info *info) 709{ 710 if (unlikely(info->index >= info->map->max_entries)) 711 return NULL; 712 713 info->sk = __sock_map_lookup_elem(info->map, info->index); 714 715 /* can't return sk directly, since that might be NULL */ 716 return info; 717} 718 719static void *sock_map_seq_start(struct seq_file *seq, loff_t *pos) 720 __acquires(rcu) 721{ 722 struct sock_map_seq_info *info = seq->private; 723 724 if (*pos == 0) 725 ++*pos; 726 727 /* pairs with sock_map_seq_stop */ 728 rcu_read_lock(); 729 return sock_map_seq_lookup_elem(info); 730} 731 732static void *sock_map_seq_next(struct seq_file *seq, void *v, loff_t *pos) 733 __must_hold(rcu) 734{ 735 struct sock_map_seq_info *info = seq->private; 736 737 ++*pos; 738 ++info->index; 739 740 return sock_map_seq_lookup_elem(info); 741} 742 743static int sock_map_seq_show(struct seq_file *seq, void *v) 744 __must_hold(rcu) 745{ 746 struct sock_map_seq_info *info = seq->private; 747 struct bpf_iter__sockmap ctx = {}; 748 struct bpf_iter_meta meta; 749 struct bpf_prog *prog; 750 751 meta.seq = seq; 752 prog = bpf_iter_get_info(&meta, !v); 753 if (!prog) 754 return 0; 755 756 ctx.meta = &meta; 757 ctx.map = info->map; 758 if (v) { 759 ctx.key = &info->index; 760 ctx.sk = info->sk; 761 } 762 763 return bpf_iter_run_prog(prog, &ctx); 764} 765 766static void sock_map_seq_stop(struct seq_file *seq, void *v) 767 __releases(rcu) 768{ 769 if (!v) 770 (void)sock_map_seq_show(seq, NULL); 771 772 /* pairs with sock_map_seq_start */ 773 rcu_read_unlock(); 774} 775 776static const struct seq_operations sock_map_seq_ops = { 777 .start = sock_map_seq_start, 778 .next = sock_map_seq_next, 779 .stop = sock_map_seq_stop, 780 .show = sock_map_seq_show, 781}; 782 783static int sock_map_init_seq_private(void *priv_data, 784 struct bpf_iter_aux_info *aux) 785{ 786 struct sock_map_seq_info *info = priv_data; 787 788 bpf_map_inc_with_uref(aux->map); 789 info->map = aux->map; 790 return 0; 791} 792 793static void sock_map_fini_seq_private(void *priv_data) 794{ 795 struct sock_map_seq_info *info = priv_data; 796 797 bpf_map_put_with_uref(info->map); 798} 799 800static u64 sock_map_mem_usage(const struct bpf_map *map) 801{ 802 u64 usage = sizeof(struct bpf_stab); 803 804 usage += (u64)map->max_entries * sizeof(struct sock *); 805 return usage; 806} 807 808static const struct bpf_iter_seq_info sock_map_iter_seq_info = { 809 .seq_ops = &sock_map_seq_ops, 810 .init_seq_private = sock_map_init_seq_private, 811 .fini_seq_private = sock_map_fini_seq_private, 812 .seq_priv_size = sizeof(struct sock_map_seq_info), 813}; 814 815BTF_ID_LIST_SINGLE(sock_map_btf_ids, struct, bpf_stab) 816const struct bpf_map_ops sock_map_ops = { 817 .map_meta_equal = bpf_map_meta_equal, 818 .map_alloc = sock_map_alloc, 819 .map_free = sock_map_free, 820 .map_get_next_key = sock_map_get_next_key, 821 .map_lookup_elem_sys_only = sock_map_lookup_sys, 822 .map_update_elem = sock_map_update_elem, 823 .map_delete_elem = sock_map_delete_elem, 824 .map_lookup_elem = sock_map_lookup, 825 .map_release_uref = sock_map_release_progs, 826 .map_check_btf = map_check_no_btf, 827 .map_mem_usage = sock_map_mem_usage, 828 .map_btf_id = &sock_map_btf_ids[0], 829 .iter_seq_info = &sock_map_iter_seq_info, 830}; 831 832struct bpf_shtab_elem { 833 struct rcu_head rcu; 834 u32 hash; 835 struct sock *sk; 836 struct hlist_node node; 837 u8 key[]; 838}; 839 840struct bpf_shtab_bucket { 841 struct hlist_head head; 842 spinlock_t lock; 843}; 844 845struct bpf_shtab { 846 struct bpf_map map; 847 struct bpf_shtab_bucket *buckets; 848 u32 buckets_num; 849 u32 elem_size; 850 struct sk_psock_progs progs; 851 atomic_t count; 852}; 853 854static inline u32 sock_hash_bucket_hash(const void *key, u32 len) 855{ 856 return jhash(key, len, 0); 857} 858 859static struct bpf_shtab_bucket *sock_hash_select_bucket(struct bpf_shtab *htab, 860 u32 hash) 861{ 862 return &htab->buckets[hash & (htab->buckets_num - 1)]; 863} 864 865static struct bpf_shtab_elem * 866sock_hash_lookup_elem_raw(struct hlist_head *head, u32 hash, void *key, 867 u32 key_size) 868{ 869 struct bpf_shtab_elem *elem; 870 871 hlist_for_each_entry_rcu(elem, head, node) { 872 if (elem->hash == hash && 873 !memcmp(&elem->key, key, key_size)) 874 return elem; 875 } 876 877 return NULL; 878} 879 880static struct sock *__sock_hash_lookup_elem(struct bpf_map *map, void *key) 881{ 882 struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map); 883 u32 key_size = map->key_size, hash; 884 struct bpf_shtab_bucket *bucket; 885 struct bpf_shtab_elem *elem; 886 887 WARN_ON_ONCE(!rcu_read_lock_held()); 888 889 hash = sock_hash_bucket_hash(key, key_size); 890 bucket = sock_hash_select_bucket(htab, hash); 891 elem = sock_hash_lookup_elem_raw(&bucket->head, hash, key, key_size); 892 893 return elem ? elem->sk : NULL; 894} 895 896static void sock_hash_free_elem(struct bpf_shtab *htab, 897 struct bpf_shtab_elem *elem) 898{ 899 atomic_dec(&htab->count); 900 kfree_rcu(elem, rcu); 901} 902 903static void sock_hash_delete_from_link(struct bpf_map *map, struct sock *sk, 904 void *link_raw) 905{ 906 struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map); 907 struct bpf_shtab_elem *elem_probe, *elem = link_raw; 908 struct bpf_shtab_bucket *bucket; 909 910 WARN_ON_ONCE(!rcu_read_lock_held()); 911 bucket = sock_hash_select_bucket(htab, elem->hash); 912 913 /* elem may be deleted in parallel from the map, but access here 914 * is okay since it's going away only after RCU grace period. 915 * However, we need to check whether it's still present. 916 */ 917 spin_lock_bh(&bucket->lock); 918 elem_probe = sock_hash_lookup_elem_raw(&bucket->head, elem->hash, 919 elem->key, map->key_size); 920 if (elem_probe && elem_probe == elem) { 921 hlist_del_rcu(&elem->node); 922 sock_map_unref(elem->sk, elem); 923 sock_hash_free_elem(htab, elem); 924 } 925 spin_unlock_bh(&bucket->lock); 926} 927 928static long sock_hash_delete_elem(struct bpf_map *map, void *key) 929{ 930 struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map); 931 u32 hash, key_size = map->key_size; 932 struct bpf_shtab_bucket *bucket; 933 struct bpf_shtab_elem *elem; 934 int ret = -ENOENT; 935 936 hash = sock_hash_bucket_hash(key, key_size); 937 bucket = sock_hash_select_bucket(htab, hash); 938 939 spin_lock_bh(&bucket->lock); 940 elem = sock_hash_lookup_elem_raw(&bucket->head, hash, key, key_size); 941 if (elem) { 942 hlist_del_rcu(&elem->node); 943 sock_map_unref(elem->sk, elem); 944 sock_hash_free_elem(htab, elem); 945 ret = 0; 946 } 947 spin_unlock_bh(&bucket->lock); 948 return ret; 949} 950 951static struct bpf_shtab_elem *sock_hash_alloc_elem(struct bpf_shtab *htab, 952 void *key, u32 key_size, 953 u32 hash, struct sock *sk, 954 struct bpf_shtab_elem *old) 955{ 956 struct bpf_shtab_elem *new; 957 958 if (atomic_inc_return(&htab->count) > htab->map.max_entries) { 959 if (!old) { 960 atomic_dec(&htab->count); 961 return ERR_PTR(-E2BIG); 962 } 963 } 964 965 new = bpf_map_kmalloc_node(&htab->map, htab->elem_size, 966 GFP_ATOMIC | __GFP_NOWARN, 967 htab->map.numa_node); 968 if (!new) { 969 atomic_dec(&htab->count); 970 return ERR_PTR(-ENOMEM); 971 } 972 memcpy(new->key, key, key_size); 973 new->sk = sk; 974 new->hash = hash; 975 return new; 976} 977 978static int sock_hash_update_common(struct bpf_map *map, void *key, 979 struct sock *sk, u64 flags) 980{ 981 struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map); 982 u32 key_size = map->key_size, hash; 983 struct bpf_shtab_elem *elem, *elem_new; 984 struct bpf_shtab_bucket *bucket; 985 struct sk_psock_link *link; 986 struct sk_psock *psock; 987 int ret; 988 989 WARN_ON_ONCE(!rcu_read_lock_held()); 990 if (unlikely(flags > BPF_EXIST)) 991 return -EINVAL; 992 993 link = sk_psock_init_link(); 994 if (!link) 995 return -ENOMEM; 996 997 ret = sock_map_link(map, sk); 998 if (ret < 0) 999 goto out_free; 1000 1001 psock = sk_psock(sk); 1002 WARN_ON_ONCE(!psock); 1003 1004 hash = sock_hash_bucket_hash(key, key_size); 1005 bucket = sock_hash_select_bucket(htab, hash); 1006 1007 spin_lock_bh(&bucket->lock); 1008 elem = sock_hash_lookup_elem_raw(&bucket->head, hash, key, key_size); 1009 if (elem && flags == BPF_NOEXIST) { 1010 ret = -EEXIST; 1011 goto out_unlock; 1012 } else if (!elem && flags == BPF_EXIST) { 1013 ret = -ENOENT; 1014 goto out_unlock; 1015 } 1016 1017 elem_new = sock_hash_alloc_elem(htab, key, key_size, hash, sk, elem); 1018 if (IS_ERR(elem_new)) { 1019 ret = PTR_ERR(elem_new); 1020 goto out_unlock; 1021 } 1022 1023 sock_map_add_link(psock, link, map, elem_new); 1024 /* Add new element to the head of the list, so that 1025 * concurrent search will find it before old elem. 1026 */ 1027 hlist_add_head_rcu(&elem_new->node, &bucket->head); 1028 if (elem) { 1029 hlist_del_rcu(&elem->node); 1030 sock_map_unref(elem->sk, elem); 1031 sock_hash_free_elem(htab, elem); 1032 } 1033 spin_unlock_bh(&bucket->lock); 1034 return 0; 1035out_unlock: 1036 spin_unlock_bh(&bucket->lock); 1037 sk_psock_put(sk, psock); 1038out_free: 1039 sk_psock_free_link(link); 1040 return ret; 1041} 1042 1043static int sock_hash_get_next_key(struct bpf_map *map, void *key, 1044 void *key_next) 1045{ 1046 struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map); 1047 struct bpf_shtab_elem *elem, *elem_next; 1048 u32 hash, key_size = map->key_size; 1049 struct hlist_head *head; 1050 int i = 0; 1051 1052 if (!key) 1053 goto find_first_elem; 1054 hash = sock_hash_bucket_hash(key, key_size); 1055 head = &sock_hash_select_bucket(htab, hash)->head; 1056 elem = sock_hash_lookup_elem_raw(head, hash, key, key_size); 1057 if (!elem) 1058 goto find_first_elem; 1059 1060 elem_next = hlist_entry_safe(rcu_dereference(hlist_next_rcu(&elem->node)), 1061 struct bpf_shtab_elem, node); 1062 if (elem_next) { 1063 memcpy(key_next, elem_next->key, key_size); 1064 return 0; 1065 } 1066 1067 i = hash & (htab->buckets_num - 1); 1068 i++; 1069find_first_elem: 1070 for (; i < htab->buckets_num; i++) { 1071 head = &sock_hash_select_bucket(htab, i)->head; 1072 elem_next = hlist_entry_safe(rcu_dereference(hlist_first_rcu(head)), 1073 struct bpf_shtab_elem, node); 1074 if (elem_next) { 1075 memcpy(key_next, elem_next->key, key_size); 1076 return 0; 1077 } 1078 } 1079 1080 return -ENOENT; 1081} 1082 1083static struct bpf_map *sock_hash_alloc(union bpf_attr *attr) 1084{ 1085 struct bpf_shtab *htab; 1086 int i, err; 1087 1088 if (attr->max_entries == 0 || 1089 attr->key_size == 0 || 1090 (attr->value_size != sizeof(u32) && 1091 attr->value_size != sizeof(u64)) || 1092 attr->map_flags & ~SOCK_CREATE_FLAG_MASK) 1093 return ERR_PTR(-EINVAL); 1094 if (attr->key_size > MAX_BPF_STACK) 1095 return ERR_PTR(-E2BIG); 1096 1097 htab = bpf_map_area_alloc(sizeof(*htab), NUMA_NO_NODE); 1098 if (!htab) 1099 return ERR_PTR(-ENOMEM); 1100 1101 bpf_map_init_from_attr(&htab->map, attr); 1102 1103 htab->buckets_num = roundup_pow_of_two(htab->map.max_entries); 1104 htab->elem_size = sizeof(struct bpf_shtab_elem) + 1105 round_up(htab->map.key_size, 8); 1106 if (htab->buckets_num == 0 || 1107 htab->buckets_num > U32_MAX / sizeof(struct bpf_shtab_bucket)) { 1108 err = -EINVAL; 1109 goto free_htab; 1110 } 1111 1112 htab->buckets = bpf_map_area_alloc(htab->buckets_num * 1113 sizeof(struct bpf_shtab_bucket), 1114 htab->map.numa_node); 1115 if (!htab->buckets) { 1116 err = -ENOMEM; 1117 goto free_htab; 1118 } 1119 1120 for (i = 0; i < htab->buckets_num; i++) { 1121 INIT_HLIST_HEAD(&htab->buckets[i].head); 1122 spin_lock_init(&htab->buckets[i].lock); 1123 } 1124 1125 return &htab->map; 1126free_htab: 1127 bpf_map_area_free(htab); 1128 return ERR_PTR(err); 1129} 1130 1131static void sock_hash_free(struct bpf_map *map) 1132{ 1133 struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map); 1134 struct bpf_shtab_bucket *bucket; 1135 struct hlist_head unlink_list; 1136 struct bpf_shtab_elem *elem; 1137 struct hlist_node *node; 1138 int i; 1139 1140 /* After the sync no updates or deletes will be in-flight so it 1141 * is safe to walk map and remove entries without risking a race 1142 * in EEXIST update case. 1143 */ 1144 synchronize_rcu(); 1145 for (i = 0; i < htab->buckets_num; i++) { 1146 bucket = sock_hash_select_bucket(htab, i); 1147 1148 /* We are racing with sock_hash_delete_from_link to 1149 * enter the spin-lock critical section. Every socket on 1150 * the list is still linked to sockhash. Since link 1151 * exists, psock exists and holds a ref to socket. That 1152 * lets us to grab a socket ref too. 1153 */ 1154 spin_lock_bh(&bucket->lock); 1155 hlist_for_each_entry(elem, &bucket->head, node) 1156 sock_hold(elem->sk); 1157 hlist_move_list(&bucket->head, &unlink_list); 1158 spin_unlock_bh(&bucket->lock); 1159 1160 /* Process removed entries out of atomic context to 1161 * block for socket lock before deleting the psock's 1162 * link to sockhash. 1163 */ 1164 hlist_for_each_entry_safe(elem, node, &unlink_list, node) { 1165 hlist_del(&elem->node); 1166 lock_sock(elem->sk); 1167 rcu_read_lock(); 1168 sock_map_unref(elem->sk, elem); 1169 rcu_read_unlock(); 1170 release_sock(elem->sk); 1171 sock_put(elem->sk); 1172 sock_hash_free_elem(htab, elem); 1173 } 1174 } 1175 1176 /* wait for psock readers accessing its map link */ 1177 synchronize_rcu(); 1178 1179 bpf_map_area_free(htab->buckets); 1180 bpf_map_area_free(htab); 1181} 1182 1183static void *sock_hash_lookup_sys(struct bpf_map *map, void *key) 1184{ 1185 struct sock *sk; 1186 1187 if (map->value_size != sizeof(u64)) 1188 return ERR_PTR(-ENOSPC); 1189 1190 sk = __sock_hash_lookup_elem(map, key); 1191 if (!sk) 1192 return ERR_PTR(-ENOENT); 1193 1194 __sock_gen_cookie(sk); 1195 return &sk->sk_cookie; 1196} 1197 1198static void *sock_hash_lookup(struct bpf_map *map, void *key) 1199{ 1200 struct sock *sk; 1201 1202 sk = __sock_hash_lookup_elem(map, key); 1203 if (!sk) 1204 return NULL; 1205 if (sk_is_refcounted(sk) && !refcount_inc_not_zero(&sk->sk_refcnt)) 1206 return NULL; 1207 return sk; 1208} 1209 1210static void sock_hash_release_progs(struct bpf_map *map) 1211{ 1212 psock_progs_drop(&container_of(map, struct bpf_shtab, map)->progs); 1213} 1214 1215BPF_CALL_4(bpf_sock_hash_update, struct bpf_sock_ops_kern *, sops, 1216 struct bpf_map *, map, void *, key, u64, flags) 1217{ 1218 WARN_ON_ONCE(!rcu_read_lock_held()); 1219 1220 if (likely(sock_map_sk_is_suitable(sops->sk) && 1221 sock_map_op_okay(sops))) 1222 return sock_hash_update_common(map, key, sops->sk, flags); 1223 return -EOPNOTSUPP; 1224} 1225 1226const struct bpf_func_proto bpf_sock_hash_update_proto = { 1227 .func = bpf_sock_hash_update, 1228 .gpl_only = false, 1229 .pkt_access = true, 1230 .ret_type = RET_INTEGER, 1231 .arg1_type = ARG_PTR_TO_CTX, 1232 .arg2_type = ARG_CONST_MAP_PTR, 1233 .arg3_type = ARG_PTR_TO_MAP_KEY, 1234 .arg4_type = ARG_ANYTHING, 1235}; 1236 1237BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb, 1238 struct bpf_map *, map, void *, key, u64, flags) 1239{ 1240 struct sock *sk; 1241 1242 if (unlikely(flags & ~(BPF_F_INGRESS))) 1243 return SK_DROP; 1244 1245 sk = __sock_hash_lookup_elem(map, key); 1246 if (unlikely(!sk || !sock_map_redirect_allowed(sk))) 1247 return SK_DROP; 1248 1249 skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS); 1250 return SK_PASS; 1251} 1252 1253const struct bpf_func_proto bpf_sk_redirect_hash_proto = { 1254 .func = bpf_sk_redirect_hash, 1255 .gpl_only = false, 1256 .ret_type = RET_INTEGER, 1257 .arg1_type = ARG_PTR_TO_CTX, 1258 .arg2_type = ARG_CONST_MAP_PTR, 1259 .arg3_type = ARG_PTR_TO_MAP_KEY, 1260 .arg4_type = ARG_ANYTHING, 1261}; 1262 1263BPF_CALL_4(bpf_msg_redirect_hash, struct sk_msg *, msg, 1264 struct bpf_map *, map, void *, key, u64, flags) 1265{ 1266 struct sock *sk; 1267 1268 if (unlikely(flags & ~(BPF_F_INGRESS))) 1269 return SK_DROP; 1270 1271 sk = __sock_hash_lookup_elem(map, key); 1272 if (unlikely(!sk || !sock_map_redirect_allowed(sk))) 1273 return SK_DROP; 1274 if (!(flags & BPF_F_INGRESS) && !sk_is_tcp(sk)) 1275 return SK_DROP; 1276 1277 msg->flags = flags; 1278 msg->sk_redir = sk; 1279 return SK_PASS; 1280} 1281 1282const struct bpf_func_proto bpf_msg_redirect_hash_proto = { 1283 .func = bpf_msg_redirect_hash, 1284 .gpl_only = false, 1285 .ret_type = RET_INTEGER, 1286 .arg1_type = ARG_PTR_TO_CTX, 1287 .arg2_type = ARG_CONST_MAP_PTR, 1288 .arg3_type = ARG_PTR_TO_MAP_KEY, 1289 .arg4_type = ARG_ANYTHING, 1290}; 1291 1292struct sock_hash_seq_info { 1293 struct bpf_map *map; 1294 struct bpf_shtab *htab; 1295 u32 bucket_id; 1296}; 1297 1298static void *sock_hash_seq_find_next(struct sock_hash_seq_info *info, 1299 struct bpf_shtab_elem *prev_elem) 1300{ 1301 const struct bpf_shtab *htab = info->htab; 1302 struct bpf_shtab_bucket *bucket; 1303 struct bpf_shtab_elem *elem; 1304 struct hlist_node *node; 1305 1306 /* try to find next elem in the same bucket */ 1307 if (prev_elem) { 1308 node = rcu_dereference(hlist_next_rcu(&prev_elem->node)); 1309 elem = hlist_entry_safe(node, struct bpf_shtab_elem, node); 1310 if (elem) 1311 return elem; 1312 1313 /* no more elements, continue in the next bucket */ 1314 info->bucket_id++; 1315 } 1316 1317 for (; info->bucket_id < htab->buckets_num; info->bucket_id++) { 1318 bucket = &htab->buckets[info->bucket_id]; 1319 node = rcu_dereference(hlist_first_rcu(&bucket->head)); 1320 elem = hlist_entry_safe(node, struct bpf_shtab_elem, node); 1321 if (elem) 1322 return elem; 1323 } 1324 1325 return NULL; 1326} 1327 1328static void *sock_hash_seq_start(struct seq_file *seq, loff_t *pos) 1329 __acquires(rcu) 1330{ 1331 struct sock_hash_seq_info *info = seq->private; 1332 1333 if (*pos == 0) 1334 ++*pos; 1335 1336 /* pairs with sock_hash_seq_stop */ 1337 rcu_read_lock(); 1338 return sock_hash_seq_find_next(info, NULL); 1339} 1340 1341static void *sock_hash_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1342 __must_hold(rcu) 1343{ 1344 struct sock_hash_seq_info *info = seq->private; 1345 1346 ++*pos; 1347 return sock_hash_seq_find_next(info, v); 1348} 1349 1350static int sock_hash_seq_show(struct seq_file *seq, void *v) 1351 __must_hold(rcu) 1352{ 1353 struct sock_hash_seq_info *info = seq->private; 1354 struct bpf_iter__sockmap ctx = {}; 1355 struct bpf_shtab_elem *elem = v; 1356 struct bpf_iter_meta meta; 1357 struct bpf_prog *prog; 1358 1359 meta.seq = seq; 1360 prog = bpf_iter_get_info(&meta, !elem); 1361 if (!prog) 1362 return 0; 1363 1364 ctx.meta = &meta; 1365 ctx.map = info->map; 1366 if (elem) { 1367 ctx.key = elem->key; 1368 ctx.sk = elem->sk; 1369 } 1370 1371 return bpf_iter_run_prog(prog, &ctx); 1372} 1373 1374static void sock_hash_seq_stop(struct seq_file *seq, void *v) 1375 __releases(rcu) 1376{ 1377 if (!v) 1378 (void)sock_hash_seq_show(seq, NULL); 1379 1380 /* pairs with sock_hash_seq_start */ 1381 rcu_read_unlock(); 1382} 1383 1384static const struct seq_operations sock_hash_seq_ops = { 1385 .start = sock_hash_seq_start, 1386 .next = sock_hash_seq_next, 1387 .stop = sock_hash_seq_stop, 1388 .show = sock_hash_seq_show, 1389}; 1390 1391static int sock_hash_init_seq_private(void *priv_data, 1392 struct bpf_iter_aux_info *aux) 1393{ 1394 struct sock_hash_seq_info *info = priv_data; 1395 1396 bpf_map_inc_with_uref(aux->map); 1397 info->map = aux->map; 1398 info->htab = container_of(aux->map, struct bpf_shtab, map); 1399 return 0; 1400} 1401 1402static void sock_hash_fini_seq_private(void *priv_data) 1403{ 1404 struct sock_hash_seq_info *info = priv_data; 1405 1406 bpf_map_put_with_uref(info->map); 1407} 1408 1409static u64 sock_hash_mem_usage(const struct bpf_map *map) 1410{ 1411 struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map); 1412 u64 usage = sizeof(*htab); 1413 1414 usage += htab->buckets_num * sizeof(struct bpf_shtab_bucket); 1415 usage += atomic_read(&htab->count) * (u64)htab->elem_size; 1416 return usage; 1417} 1418 1419static const struct bpf_iter_seq_info sock_hash_iter_seq_info = { 1420 .seq_ops = &sock_hash_seq_ops, 1421 .init_seq_private = sock_hash_init_seq_private, 1422 .fini_seq_private = sock_hash_fini_seq_private, 1423 .seq_priv_size = sizeof(struct sock_hash_seq_info), 1424}; 1425 1426BTF_ID_LIST_SINGLE(sock_hash_map_btf_ids, struct, bpf_shtab) 1427const struct bpf_map_ops sock_hash_ops = { 1428 .map_meta_equal = bpf_map_meta_equal, 1429 .map_alloc = sock_hash_alloc, 1430 .map_free = sock_hash_free, 1431 .map_get_next_key = sock_hash_get_next_key, 1432 .map_update_elem = sock_map_update_elem, 1433 .map_delete_elem = sock_hash_delete_elem, 1434 .map_lookup_elem = sock_hash_lookup, 1435 .map_lookup_elem_sys_only = sock_hash_lookup_sys, 1436 .map_release_uref = sock_hash_release_progs, 1437 .map_check_btf = map_check_no_btf, 1438 .map_mem_usage = sock_hash_mem_usage, 1439 .map_btf_id = &sock_hash_map_btf_ids[0], 1440 .iter_seq_info = &sock_hash_iter_seq_info, 1441}; 1442 1443static struct sk_psock_progs *sock_map_progs(struct bpf_map *map) 1444{ 1445 switch (map->map_type) { 1446 case BPF_MAP_TYPE_SOCKMAP: 1447 return &container_of(map, struct bpf_stab, map)->progs; 1448 case BPF_MAP_TYPE_SOCKHASH: 1449 return &container_of(map, struct bpf_shtab, map)->progs; 1450 default: 1451 break; 1452 } 1453 1454 return NULL; 1455} 1456 1457static int sock_map_prog_lookup(struct bpf_map *map, struct bpf_prog ***pprog, 1458 u32 which) 1459{ 1460 struct sk_psock_progs *progs = sock_map_progs(map); 1461 1462 if (!progs) 1463 return -EOPNOTSUPP; 1464 1465 switch (which) { 1466 case BPF_SK_MSG_VERDICT: 1467 *pprog = &progs->msg_parser; 1468 break; 1469#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER) 1470 case BPF_SK_SKB_STREAM_PARSER: 1471 *pprog = &progs->stream_parser; 1472 break; 1473#endif 1474 case BPF_SK_SKB_STREAM_VERDICT: 1475 if (progs->skb_verdict) 1476 return -EBUSY; 1477 *pprog = &progs->stream_verdict; 1478 break; 1479 case BPF_SK_SKB_VERDICT: 1480 if (progs->stream_verdict) 1481 return -EBUSY; 1482 *pprog = &progs->skb_verdict; 1483 break; 1484 default: 1485 return -EOPNOTSUPP; 1486 } 1487 1488 return 0; 1489} 1490 1491static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog, 1492 struct bpf_prog *old, u32 which) 1493{ 1494 struct bpf_prog **pprog; 1495 int ret; 1496 1497 ret = sock_map_prog_lookup(map, &pprog, which); 1498 if (ret) 1499 return ret; 1500 1501 if (old) 1502 return psock_replace_prog(pprog, prog, old); 1503 1504 psock_set_prog(pprog, prog); 1505 return 0; 1506} 1507 1508int sock_map_bpf_prog_query(const union bpf_attr *attr, 1509 union bpf_attr __user *uattr) 1510{ 1511 __u32 __user *prog_ids = u64_to_user_ptr(attr->query.prog_ids); 1512 u32 prog_cnt = 0, flags = 0, ufd = attr->target_fd; 1513 struct bpf_prog **pprog; 1514 struct bpf_prog *prog; 1515 struct bpf_map *map; 1516 struct fd f; 1517 u32 id = 0; 1518 int ret; 1519 1520 if (attr->query.query_flags) 1521 return -EINVAL; 1522 1523 f = fdget(ufd); 1524 map = __bpf_map_get(f); 1525 if (IS_ERR(map)) 1526 return PTR_ERR(map); 1527 1528 rcu_read_lock(); 1529 1530 ret = sock_map_prog_lookup(map, &pprog, attr->query.attach_type); 1531 if (ret) 1532 goto end; 1533 1534 prog = *pprog; 1535 prog_cnt = !prog ? 0 : 1; 1536 1537 if (!attr->query.prog_cnt || !prog_ids || !prog_cnt) 1538 goto end; 1539 1540 /* we do not hold the refcnt, the bpf prog may be released 1541 * asynchronously and the id would be set to 0. 1542 */ 1543 id = data_race(prog->aux->id); 1544 if (id == 0) 1545 prog_cnt = 0; 1546 1547end: 1548 rcu_read_unlock(); 1549 1550 if (copy_to_user(&uattr->query.attach_flags, &flags, sizeof(flags)) || 1551 (id != 0 && copy_to_user(prog_ids, &id, sizeof(u32))) || 1552 copy_to_user(&uattr->query.prog_cnt, &prog_cnt, sizeof(prog_cnt))) 1553 ret = -EFAULT; 1554 1555 fdput(f); 1556 return ret; 1557} 1558 1559static void sock_map_unlink(struct sock *sk, struct sk_psock_link *link) 1560{ 1561 switch (link->map->map_type) { 1562 case BPF_MAP_TYPE_SOCKMAP: 1563 return sock_map_delete_from_link(link->map, sk, 1564 link->link_raw); 1565 case BPF_MAP_TYPE_SOCKHASH: 1566 return sock_hash_delete_from_link(link->map, sk, 1567 link->link_raw); 1568 default: 1569 break; 1570 } 1571} 1572 1573static void sock_map_remove_links(struct sock *sk, struct sk_psock *psock) 1574{ 1575 struct sk_psock_link *link; 1576 1577 while ((link = sk_psock_link_pop(psock))) { 1578 sock_map_unlink(sk, link); 1579 sk_psock_free_link(link); 1580 } 1581} 1582 1583void sock_map_unhash(struct sock *sk) 1584{ 1585 void (*saved_unhash)(struct sock *sk); 1586 struct sk_psock *psock; 1587 1588 rcu_read_lock(); 1589 psock = sk_psock(sk); 1590 if (unlikely(!psock)) { 1591 rcu_read_unlock(); 1592 saved_unhash = READ_ONCE(sk->sk_prot)->unhash; 1593 } else { 1594 saved_unhash = psock->saved_unhash; 1595 sock_map_remove_links(sk, psock); 1596 rcu_read_unlock(); 1597 } 1598 if (WARN_ON_ONCE(saved_unhash == sock_map_unhash)) 1599 return; 1600 if (saved_unhash) 1601 saved_unhash(sk); 1602} 1603EXPORT_SYMBOL_GPL(sock_map_unhash); 1604 1605void sock_map_destroy(struct sock *sk) 1606{ 1607 void (*saved_destroy)(struct sock *sk); 1608 struct sk_psock *psock; 1609 1610 rcu_read_lock(); 1611 psock = sk_psock_get(sk); 1612 if (unlikely(!psock)) { 1613 rcu_read_unlock(); 1614 saved_destroy = READ_ONCE(sk->sk_prot)->destroy; 1615 } else { 1616 saved_destroy = psock->saved_destroy; 1617 sock_map_remove_links(sk, psock); 1618 rcu_read_unlock(); 1619 sk_psock_stop(psock); 1620 sk_psock_put(sk, psock); 1621 } 1622 if (WARN_ON_ONCE(saved_destroy == sock_map_destroy)) 1623 return; 1624 if (saved_destroy) 1625 saved_destroy(sk); 1626} 1627EXPORT_SYMBOL_GPL(sock_map_destroy); 1628 1629void sock_map_close(struct sock *sk, long timeout) 1630{ 1631 void (*saved_close)(struct sock *sk, long timeout); 1632 struct sk_psock *psock; 1633 1634 lock_sock(sk); 1635 rcu_read_lock(); 1636 psock = sk_psock_get(sk); 1637 if (unlikely(!psock)) { 1638 rcu_read_unlock(); 1639 release_sock(sk); 1640 saved_close = READ_ONCE(sk->sk_prot)->close; 1641 } else { 1642 saved_close = psock->saved_close; 1643 sock_map_remove_links(sk, psock); 1644 rcu_read_unlock(); 1645 sk_psock_stop(psock); 1646 release_sock(sk); 1647 cancel_delayed_work_sync(&psock->work); 1648 sk_psock_put(sk, psock); 1649 } 1650 1651 /* Make sure we do not recurse. This is a bug. 1652 * Leak the socket instead of crashing on a stack overflow. 1653 */ 1654 if (WARN_ON_ONCE(saved_close == sock_map_close)) 1655 return; 1656 saved_close(sk, timeout); 1657} 1658EXPORT_SYMBOL_GPL(sock_map_close); 1659 1660static int sock_map_iter_attach_target(struct bpf_prog *prog, 1661 union bpf_iter_link_info *linfo, 1662 struct bpf_iter_aux_info *aux) 1663{ 1664 struct bpf_map *map; 1665 int err = -EINVAL; 1666 1667 if (!linfo->map.map_fd) 1668 return -EBADF; 1669 1670 map = bpf_map_get_with_uref(linfo->map.map_fd); 1671 if (IS_ERR(map)) 1672 return PTR_ERR(map); 1673 1674 if (map->map_type != BPF_MAP_TYPE_SOCKMAP && 1675 map->map_type != BPF_MAP_TYPE_SOCKHASH) 1676 goto put_map; 1677 1678 if (prog->aux->max_rdonly_access > map->key_size) { 1679 err = -EACCES; 1680 goto put_map; 1681 } 1682 1683 aux->map = map; 1684 return 0; 1685 1686put_map: 1687 bpf_map_put_with_uref(map); 1688 return err; 1689} 1690 1691static void sock_map_iter_detach_target(struct bpf_iter_aux_info *aux) 1692{ 1693 bpf_map_put_with_uref(aux->map); 1694} 1695 1696static struct bpf_iter_reg sock_map_iter_reg = { 1697 .target = "sockmap", 1698 .attach_target = sock_map_iter_attach_target, 1699 .detach_target = sock_map_iter_detach_target, 1700 .show_fdinfo = bpf_iter_map_show_fdinfo, 1701 .fill_link_info = bpf_iter_map_fill_link_info, 1702 .ctx_arg_info_size = 2, 1703 .ctx_arg_info = { 1704 { offsetof(struct bpf_iter__sockmap, key), 1705 PTR_TO_BUF | PTR_MAYBE_NULL | MEM_RDONLY }, 1706 { offsetof(struct bpf_iter__sockmap, sk), 1707 PTR_TO_BTF_ID_OR_NULL }, 1708 }, 1709}; 1710 1711static int __init bpf_sockmap_iter_init(void) 1712{ 1713 sock_map_iter_reg.ctx_arg_info[1].btf_id = 1714 btf_sock_ids[BTF_SOCK_TYPE_SOCK]; 1715 return bpf_iter_reg_target(&sock_map_iter_reg); 1716} 1717late_initcall(bpf_sockmap_iter_init); 1718