1 /* 2 * NETLINK Kernel-user communication protocol. 3 * 4 * Authors: Alan Cox <alan@lxorguk.ukuu.org.uk> 5 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 * 12 * Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith 13 * added netlink_proto_exit 14 * Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br> 15 * use nlk_sk, as sk->protinfo is on a diet 8) 16 * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org> 17 * - inc module use count of module that owns 18 * the kernel socket in case userspace opens 19 * socket of same protocol 20 * - remove all module support, since netlink is 21 * mandatory if CONFIG_NET=y these days 22 */ 23 24 #include <linux/module.h> 25 26 #include <linux/capability.h> 27 #include <linux/kernel.h> 28 #include <linux/init.h> 29 #include <linux/signal.h> 30 #include <linux/sched.h> 31 #include <linux/errno.h> 32 #include <linux/string.h> 33 #include <linux/stat.h> 34 #include <linux/socket.h> 35 #include <linux/un.h> 36 #include <linux/fcntl.h> 37 #include <linux/termios.h> 38 #include <linux/sockios.h> 39 #include <linux/net.h> 40 #include <linux/fs.h> 41 #include <linux/slab.h> 42 #include <asm/uaccess.h> 43 #include <linux/skbuff.h> 44 #include <linux/netdevice.h> 45 #include <linux/rtnetlink.h> 46 #include <linux/proc_fs.h> 47 #include <linux/seq_file.h> 48 #include <linux/notifier.h> 49 #include <linux/security.h> 50 #include <linux/jhash.h> 51 #include <linux/jiffies.h> 52 #include <linux/random.h> 53 #include <linux/bitops.h> 54 #include <linux/mm.h> 55 #include <linux/types.h> 56 #include <linux/audit.h> 57 #include <linux/mutex.h> 58 59 #include <net/net_namespace.h> 60 #include <net/sock.h> 61 #include <net/scm.h> 62 #include <net/netlink.h> 63 64 #define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8) 65 #define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long)) 66 67 struct netlink_sock { 68 /* struct sock has to be the first member of netlink_sock */ 69 struct sock sk; 70 u32 pid; 71 u32 dst_pid; 72 u32 dst_group; 73 u32 flags; 74 u32 subscriptions; 75 u32 ngroups; 76 unsigned long *groups; 77 unsigned long state; 78 wait_queue_head_t wait; 79 struct netlink_callback *cb; 80 struct mutex *cb_mutex; 81 struct mutex cb_def_mutex; 82 void (*netlink_rcv)(struct sk_buff *skb); 83 struct module *module; 84 }; 85 86 struct listeners { 87 struct rcu_head rcu; 88 unsigned long masks[0]; 89 }; 90 91 #define NETLINK_KERNEL_SOCKET 0x1 92 #define NETLINK_RECV_PKTINFO 0x2 93 #define NETLINK_BROADCAST_SEND_ERROR 0x4 94 #define NETLINK_RECV_NO_ENOBUFS 0x8 95 96 static inline struct netlink_sock *nlk_sk(struct sock *sk) 97 { 98 return container_of(sk, struct netlink_sock, sk); 99 } 100 101 static inline int netlink_is_kernel(struct sock *sk) 102 { 103 return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET; 104 } 105 106 struct nl_pid_hash { 107 struct hlist_head *table; 108 unsigned long rehash_time; 109 110 unsigned int mask; 111 unsigned int shift; 112 113 unsigned int entries; 114 unsigned int max_shift; 115 116 u32 rnd; 117 }; 118 119 struct netlink_table { 120 struct nl_pid_hash hash; 121 struct hlist_head mc_list; 122 struct listeners __rcu *listeners; 123 unsigned int nl_nonroot; 124 unsigned int groups; 125 struct mutex *cb_mutex; 126 struct module *module; 127 int registered; 128 }; 129 130 static struct netlink_table *nl_table; 131 132 static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait); 133 134 static int netlink_dump(struct sock *sk); 135 static void netlink_destroy_callback(struct netlink_callback *cb); 136 137 static DEFINE_RWLOCK(nl_table_lock); 138 static atomic_t nl_table_users = ATOMIC_INIT(0); 139 140 static ATOMIC_NOTIFIER_HEAD(netlink_chain); 141 142 static inline u32 netlink_group_mask(u32 group) 143 { 144 return group ? 1 << (group - 1) : 0; 145 } 146 147 static inline struct hlist_head *nl_pid_hashfn(struct nl_pid_hash *hash, u32 pid) 148 { 149 return &hash->table[jhash_1word(pid, hash->rnd) & hash->mask]; 150 } 151 152 static void netlink_sock_destruct(struct sock *sk) 153 { 154 struct netlink_sock *nlk = nlk_sk(sk); 155 156 if (nlk->cb) { 157 if (nlk->cb->done) 158 nlk->cb->done(nlk->cb); 159 netlink_destroy_callback(nlk->cb); 160 } 161 162 skb_queue_purge(&sk->sk_receive_queue); 163 164 if (!sock_flag(sk, SOCK_DEAD)) { 165 printk(KERN_ERR "Freeing alive netlink socket %p\n", sk); 166 return; 167 } 168 169 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 170 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 171 WARN_ON(nlk_sk(sk)->groups); 172 } 173 174 /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on 175 * SMP. Look, when several writers sleep and reader wakes them up, all but one 176 * immediately hit write lock and grab all the cpus. Exclusive sleep solves 177 * this, _but_ remember, it adds useless work on UP machines. 178 */ 179 180 void netlink_table_grab(void) 181 __acquires(nl_table_lock) 182 { 183 might_sleep(); 184 185 write_lock_irq(&nl_table_lock); 186 187 if (atomic_read(&nl_table_users)) { 188 DECLARE_WAITQUEUE(wait, current); 189 190 add_wait_queue_exclusive(&nl_table_wait, &wait); 191 for (;;) { 192 set_current_state(TASK_UNINTERRUPTIBLE); 193 if (atomic_read(&nl_table_users) == 0) 194 break; 195 write_unlock_irq(&nl_table_lock); 196 schedule(); 197 write_lock_irq(&nl_table_lock); 198 } 199 200 __set_current_state(TASK_RUNNING); 201 remove_wait_queue(&nl_table_wait, &wait); 202 } 203 } 204 205 void netlink_table_ungrab(void) 206 __releases(nl_table_lock) 207 { 208 write_unlock_irq(&nl_table_lock); 209 wake_up(&nl_table_wait); 210 } 211 212 static inline void 213 netlink_lock_table(void) 214 { 215 /* read_lock() synchronizes us to netlink_table_grab */ 216 217 read_lock(&nl_table_lock); 218 atomic_inc(&nl_table_users); 219 read_unlock(&nl_table_lock); 220 } 221 222 static inline void 223 netlink_unlock_table(void) 224 { 225 if (atomic_dec_and_test(&nl_table_users)) 226 wake_up(&nl_table_wait); 227 } 228 229 static struct sock *netlink_lookup(struct net *net, int protocol, u32 pid) 230 { 231 struct nl_pid_hash *hash = &nl_table[protocol].hash; 232 struct hlist_head *head; 233 struct sock *sk; 234 struct hlist_node *node; 235 236 read_lock(&nl_table_lock); 237 head = nl_pid_hashfn(hash, pid); 238 sk_for_each(sk, node, head) { 239 if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->pid == pid)) { 240 sock_hold(sk); 241 goto found; 242 } 243 } 244 sk = NULL; 245 found: 246 read_unlock(&nl_table_lock); 247 return sk; 248 } 249 250 static struct hlist_head *nl_pid_hash_zalloc(size_t size) 251 { 252 if (size <= PAGE_SIZE) 253 return kzalloc(size, GFP_ATOMIC); 254 else 255 return (struct hlist_head *) 256 __get_free_pages(GFP_ATOMIC | __GFP_ZERO, 257 get_order(size)); 258 } 259 260 static void nl_pid_hash_free(struct hlist_head *table, size_t size) 261 { 262 if (size <= PAGE_SIZE) 263 kfree(table); 264 else 265 free_pages((unsigned long)table, get_order(size)); 266 } 267 268 static int nl_pid_hash_rehash(struct nl_pid_hash *hash, int grow) 269 { 270 unsigned int omask, mask, shift; 271 size_t osize, size; 272 struct hlist_head *otable, *table; 273 int i; 274 275 omask = mask = hash->mask; 276 osize = size = (mask + 1) * sizeof(*table); 277 shift = hash->shift; 278 279 if (grow) { 280 if (++shift > hash->max_shift) 281 return 0; 282 mask = mask * 2 + 1; 283 size *= 2; 284 } 285 286 table = nl_pid_hash_zalloc(size); 287 if (!table) 288 return 0; 289 290 otable = hash->table; 291 hash->table = table; 292 hash->mask = mask; 293 hash->shift = shift; 294 get_random_bytes(&hash->rnd, sizeof(hash->rnd)); 295 296 for (i = 0; i <= omask; i++) { 297 struct sock *sk; 298 struct hlist_node *node, *tmp; 299 300 sk_for_each_safe(sk, node, tmp, &otable[i]) 301 __sk_add_node(sk, nl_pid_hashfn(hash, nlk_sk(sk)->pid)); 302 } 303 304 nl_pid_hash_free(otable, osize); 305 hash->rehash_time = jiffies + 10 * 60 * HZ; 306 return 1; 307 } 308 309 static inline int nl_pid_hash_dilute(struct nl_pid_hash *hash, int len) 310 { 311 int avg = hash->entries >> hash->shift; 312 313 if (unlikely(avg > 1) && nl_pid_hash_rehash(hash, 1)) 314 return 1; 315 316 if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) { 317 nl_pid_hash_rehash(hash, 0); 318 return 1; 319 } 320 321 return 0; 322 } 323 324 static const struct proto_ops netlink_ops; 325 326 static void 327 netlink_update_listeners(struct sock *sk) 328 { 329 struct netlink_table *tbl = &nl_table[sk->sk_protocol]; 330 struct hlist_node *node; 331 unsigned long mask; 332 unsigned int i; 333 334 for (i = 0; i < NLGRPLONGS(tbl->groups); i++) { 335 mask = 0; 336 sk_for_each_bound(sk, node, &tbl->mc_list) { 337 if (i < NLGRPLONGS(nlk_sk(sk)->ngroups)) 338 mask |= nlk_sk(sk)->groups[i]; 339 } 340 tbl->listeners->masks[i] = mask; 341 } 342 /* this function is only called with the netlink table "grabbed", which 343 * makes sure updates are visible before bind or setsockopt return. */ 344 } 345 346 static int netlink_insert(struct sock *sk, struct net *net, u32 pid) 347 { 348 struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash; 349 struct hlist_head *head; 350 int err = -EADDRINUSE; 351 struct sock *osk; 352 struct hlist_node *node; 353 int len; 354 355 netlink_table_grab(); 356 head = nl_pid_hashfn(hash, pid); 357 len = 0; 358 sk_for_each(osk, node, head) { 359 if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->pid == pid)) 360 break; 361 len++; 362 } 363 if (node) 364 goto err; 365 366 err = -EBUSY; 367 if (nlk_sk(sk)->pid) 368 goto err; 369 370 err = -ENOMEM; 371 if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX)) 372 goto err; 373 374 if (len && nl_pid_hash_dilute(hash, len)) 375 head = nl_pid_hashfn(hash, pid); 376 hash->entries++; 377 nlk_sk(sk)->pid = pid; 378 sk_add_node(sk, head); 379 err = 0; 380 381 err: 382 netlink_table_ungrab(); 383 return err; 384 } 385 386 static void netlink_remove(struct sock *sk) 387 { 388 netlink_table_grab(); 389 if (sk_del_node_init(sk)) 390 nl_table[sk->sk_protocol].hash.entries--; 391 if (nlk_sk(sk)->subscriptions) 392 __sk_del_bind_node(sk); 393 netlink_table_ungrab(); 394 } 395 396 static struct proto netlink_proto = { 397 .name = "NETLINK", 398 .owner = THIS_MODULE, 399 .obj_size = sizeof(struct netlink_sock), 400 }; 401 402 static int __netlink_create(struct net *net, struct socket *sock, 403 struct mutex *cb_mutex, int protocol) 404 { 405 struct sock *sk; 406 struct netlink_sock *nlk; 407 408 sock->ops = &netlink_ops; 409 410 sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto); 411 if (!sk) 412 return -ENOMEM; 413 414 sock_init_data(sock, sk); 415 416 nlk = nlk_sk(sk); 417 if (cb_mutex) 418 nlk->cb_mutex = cb_mutex; 419 else { 420 nlk->cb_mutex = &nlk->cb_def_mutex; 421 mutex_init(nlk->cb_mutex); 422 } 423 init_waitqueue_head(&nlk->wait); 424 425 sk->sk_destruct = netlink_sock_destruct; 426 sk->sk_protocol = protocol; 427 return 0; 428 } 429 430 static int netlink_create(struct net *net, struct socket *sock, int protocol, 431 int kern) 432 { 433 struct module *module = NULL; 434 struct mutex *cb_mutex; 435 struct netlink_sock *nlk; 436 int err = 0; 437 438 sock->state = SS_UNCONNECTED; 439 440 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) 441 return -ESOCKTNOSUPPORT; 442 443 if (protocol < 0 || protocol >= MAX_LINKS) 444 return -EPROTONOSUPPORT; 445 446 netlink_lock_table(); 447 #ifdef CONFIG_MODULES 448 if (!nl_table[protocol].registered) { 449 netlink_unlock_table(); 450 request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol); 451 netlink_lock_table(); 452 } 453 #endif 454 if (nl_table[protocol].registered && 455 try_module_get(nl_table[protocol].module)) 456 module = nl_table[protocol].module; 457 else 458 err = -EPROTONOSUPPORT; 459 cb_mutex = nl_table[protocol].cb_mutex; 460 netlink_unlock_table(); 461 462 if (err < 0) 463 goto out; 464 465 err = __netlink_create(net, sock, cb_mutex, protocol); 466 if (err < 0) 467 goto out_module; 468 469 local_bh_disable(); 470 sock_prot_inuse_add(net, &netlink_proto, 1); 471 local_bh_enable(); 472 473 nlk = nlk_sk(sock->sk); 474 nlk->module = module; 475 out: 476 return err; 477 478 out_module: 479 module_put(module); 480 goto out; 481 } 482 483 static int netlink_release(struct socket *sock) 484 { 485 struct sock *sk = sock->sk; 486 struct netlink_sock *nlk; 487 488 if (!sk) 489 return 0; 490 491 netlink_remove(sk); 492 sock_orphan(sk); 493 nlk = nlk_sk(sk); 494 495 /* 496 * OK. Socket is unlinked, any packets that arrive now 497 * will be purged. 498 */ 499 500 sock->sk = NULL; 501 wake_up_interruptible_all(&nlk->wait); 502 503 skb_queue_purge(&sk->sk_write_queue); 504 505 if (nlk->pid) { 506 struct netlink_notify n = { 507 .net = sock_net(sk), 508 .protocol = sk->sk_protocol, 509 .pid = nlk->pid, 510 }; 511 atomic_notifier_call_chain(&netlink_chain, 512 NETLINK_URELEASE, &n); 513 } 514 515 module_put(nlk->module); 516 517 netlink_table_grab(); 518 if (netlink_is_kernel(sk)) { 519 BUG_ON(nl_table[sk->sk_protocol].registered == 0); 520 if (--nl_table[sk->sk_protocol].registered == 0) { 521 kfree(nl_table[sk->sk_protocol].listeners); 522 nl_table[sk->sk_protocol].module = NULL; 523 nl_table[sk->sk_protocol].registered = 0; 524 } 525 } else if (nlk->subscriptions) 526 netlink_update_listeners(sk); 527 netlink_table_ungrab(); 528 529 kfree(nlk->groups); 530 nlk->groups = NULL; 531 532 local_bh_disable(); 533 sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1); 534 local_bh_enable(); 535 sock_put(sk); 536 return 0; 537 } 538 539 static int netlink_autobind(struct socket *sock) 540 { 541 struct sock *sk = sock->sk; 542 struct net *net = sock_net(sk); 543 struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash; 544 struct hlist_head *head; 545 struct sock *osk; 546 struct hlist_node *node; 547 s32 pid = task_tgid_vnr(current); 548 int err; 549 static s32 rover = -4097; 550 551 retry: 552 cond_resched(); 553 netlink_table_grab(); 554 head = nl_pid_hashfn(hash, pid); 555 sk_for_each(osk, node, head) { 556 if (!net_eq(sock_net(osk), net)) 557 continue; 558 if (nlk_sk(osk)->pid == pid) { 559 /* Bind collision, search negative pid values. */ 560 pid = rover--; 561 if (rover > -4097) 562 rover = -4097; 563 netlink_table_ungrab(); 564 goto retry; 565 } 566 } 567 netlink_table_ungrab(); 568 569 err = netlink_insert(sk, net, pid); 570 if (err == -EADDRINUSE) 571 goto retry; 572 573 /* If 2 threads race to autobind, that is fine. */ 574 if (err == -EBUSY) 575 err = 0; 576 577 return err; 578 } 579 580 static inline int netlink_capable(const struct socket *sock, unsigned int flag) 581 { 582 return (nl_table[sock->sk->sk_protocol].nl_nonroot & flag) || 583 capable(CAP_NET_ADMIN); 584 } 585 586 static void 587 netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions) 588 { 589 struct netlink_sock *nlk = nlk_sk(sk); 590 591 if (nlk->subscriptions && !subscriptions) 592 __sk_del_bind_node(sk); 593 else if (!nlk->subscriptions && subscriptions) 594 sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list); 595 nlk->subscriptions = subscriptions; 596 } 597 598 static int netlink_realloc_groups(struct sock *sk) 599 { 600 struct netlink_sock *nlk = nlk_sk(sk); 601 unsigned int groups; 602 unsigned long *new_groups; 603 int err = 0; 604 605 netlink_table_grab(); 606 607 groups = nl_table[sk->sk_protocol].groups; 608 if (!nl_table[sk->sk_protocol].registered) { 609 err = -ENOENT; 610 goto out_unlock; 611 } 612 613 if (nlk->ngroups >= groups) 614 goto out_unlock; 615 616 new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC); 617 if (new_groups == NULL) { 618 err = -ENOMEM; 619 goto out_unlock; 620 } 621 memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0, 622 NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups)); 623 624 nlk->groups = new_groups; 625 nlk->ngroups = groups; 626 out_unlock: 627 netlink_table_ungrab(); 628 return err; 629 } 630 631 static int netlink_bind(struct socket *sock, struct sockaddr *addr, 632 int addr_len) 633 { 634 struct sock *sk = sock->sk; 635 struct net *net = sock_net(sk); 636 struct netlink_sock *nlk = nlk_sk(sk); 637 struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; 638 int err; 639 640 if (nladdr->nl_family != AF_NETLINK) 641 return -EINVAL; 642 643 /* Only superuser is allowed to listen multicasts */ 644 if (nladdr->nl_groups) { 645 if (!netlink_capable(sock, NL_NONROOT_RECV)) 646 return -EPERM; 647 err = netlink_realloc_groups(sk); 648 if (err) 649 return err; 650 } 651 652 if (nlk->pid) { 653 if (nladdr->nl_pid != nlk->pid) 654 return -EINVAL; 655 } else { 656 err = nladdr->nl_pid ? 657 netlink_insert(sk, net, nladdr->nl_pid) : 658 netlink_autobind(sock); 659 if (err) 660 return err; 661 } 662 663 if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0])) 664 return 0; 665 666 netlink_table_grab(); 667 netlink_update_subscriptions(sk, nlk->subscriptions + 668 hweight32(nladdr->nl_groups) - 669 hweight32(nlk->groups[0])); 670 nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups; 671 netlink_update_listeners(sk); 672 netlink_table_ungrab(); 673 674 return 0; 675 } 676 677 static int netlink_connect(struct socket *sock, struct sockaddr *addr, 678 int alen, int flags) 679 { 680 int err = 0; 681 struct sock *sk = sock->sk; 682 struct netlink_sock *nlk = nlk_sk(sk); 683 struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; 684 685 if (alen < sizeof(addr->sa_family)) 686 return -EINVAL; 687 688 if (addr->sa_family == AF_UNSPEC) { 689 sk->sk_state = NETLINK_UNCONNECTED; 690 nlk->dst_pid = 0; 691 nlk->dst_group = 0; 692 return 0; 693 } 694 if (addr->sa_family != AF_NETLINK) 695 return -EINVAL; 696 697 /* Only superuser is allowed to send multicasts */ 698 if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_SEND)) 699 return -EPERM; 700 701 if (!nlk->pid) 702 err = netlink_autobind(sock); 703 704 if (err == 0) { 705 sk->sk_state = NETLINK_CONNECTED; 706 nlk->dst_pid = nladdr->nl_pid; 707 nlk->dst_group = ffs(nladdr->nl_groups); 708 } 709 710 return err; 711 } 712 713 static int netlink_getname(struct socket *sock, struct sockaddr *addr, 714 int *addr_len, int peer) 715 { 716 struct sock *sk = sock->sk; 717 struct netlink_sock *nlk = nlk_sk(sk); 718 DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr); 719 720 nladdr->nl_family = AF_NETLINK; 721 nladdr->nl_pad = 0; 722 *addr_len = sizeof(*nladdr); 723 724 if (peer) { 725 nladdr->nl_pid = nlk->dst_pid; 726 nladdr->nl_groups = netlink_group_mask(nlk->dst_group); 727 } else { 728 nladdr->nl_pid = nlk->pid; 729 nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0; 730 } 731 return 0; 732 } 733 734 static void netlink_overrun(struct sock *sk) 735 { 736 struct netlink_sock *nlk = nlk_sk(sk); 737 738 if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) { 739 if (!test_and_set_bit(0, &nlk_sk(sk)->state)) { 740 sk->sk_err = ENOBUFS; 741 sk->sk_error_report(sk); 742 } 743 } 744 atomic_inc(&sk->sk_drops); 745 } 746 747 static struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid) 748 { 749 struct sock *sock; 750 struct netlink_sock *nlk; 751 752 sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, pid); 753 if (!sock) 754 return ERR_PTR(-ECONNREFUSED); 755 756 /* Don't bother queuing skb if kernel socket has no input function */ 757 nlk = nlk_sk(sock); 758 if (sock->sk_state == NETLINK_CONNECTED && 759 nlk->dst_pid != nlk_sk(ssk)->pid) { 760 sock_put(sock); 761 return ERR_PTR(-ECONNREFUSED); 762 } 763 return sock; 764 } 765 766 struct sock *netlink_getsockbyfilp(struct file *filp) 767 { 768 struct inode *inode = filp->f_path.dentry->d_inode; 769 struct sock *sock; 770 771 if (!S_ISSOCK(inode->i_mode)) 772 return ERR_PTR(-ENOTSOCK); 773 774 sock = SOCKET_I(inode)->sk; 775 if (sock->sk_family != AF_NETLINK) 776 return ERR_PTR(-EINVAL); 777 778 sock_hold(sock); 779 return sock; 780 } 781 782 /* 783 * Attach a skb to a netlink socket. 784 * The caller must hold a reference to the destination socket. On error, the 785 * reference is dropped. The skb is not send to the destination, just all 786 * all error checks are performed and memory in the queue is reserved. 787 * Return values: 788 * < 0: error. skb freed, reference to sock dropped. 789 * 0: continue 790 * 1: repeat lookup - reference dropped while waiting for socket memory. 791 */ 792 int netlink_attachskb(struct sock *sk, struct sk_buff *skb, 793 long *timeo, struct sock *ssk) 794 { 795 struct netlink_sock *nlk; 796 797 nlk = nlk_sk(sk); 798 799 if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || 800 test_bit(0, &nlk->state)) { 801 DECLARE_WAITQUEUE(wait, current); 802 if (!*timeo) { 803 if (!ssk || netlink_is_kernel(ssk)) 804 netlink_overrun(sk); 805 sock_put(sk); 806 kfree_skb(skb); 807 return -EAGAIN; 808 } 809 810 __set_current_state(TASK_INTERRUPTIBLE); 811 add_wait_queue(&nlk->wait, &wait); 812 813 if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || 814 test_bit(0, &nlk->state)) && 815 !sock_flag(sk, SOCK_DEAD)) 816 *timeo = schedule_timeout(*timeo); 817 818 __set_current_state(TASK_RUNNING); 819 remove_wait_queue(&nlk->wait, &wait); 820 sock_put(sk); 821 822 if (signal_pending(current)) { 823 kfree_skb(skb); 824 return sock_intr_errno(*timeo); 825 } 826 return 1; 827 } 828 skb_set_owner_r(skb, sk); 829 return 0; 830 } 831 832 static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb) 833 { 834 int len = skb->len; 835 836 skb_queue_tail(&sk->sk_receive_queue, skb); 837 sk->sk_data_ready(sk, len); 838 return len; 839 } 840 841 int netlink_sendskb(struct sock *sk, struct sk_buff *skb) 842 { 843 int len = __netlink_sendskb(sk, skb); 844 845 sock_put(sk); 846 return len; 847 } 848 849 void netlink_detachskb(struct sock *sk, struct sk_buff *skb) 850 { 851 kfree_skb(skb); 852 sock_put(sk); 853 } 854 855 static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation) 856 { 857 int delta; 858 859 skb_orphan(skb); 860 861 delta = skb->end - skb->tail; 862 if (delta * 2 < skb->truesize) 863 return skb; 864 865 if (skb_shared(skb)) { 866 struct sk_buff *nskb = skb_clone(skb, allocation); 867 if (!nskb) 868 return skb; 869 kfree_skb(skb); 870 skb = nskb; 871 } 872 873 if (!pskb_expand_head(skb, 0, -delta, allocation)) 874 skb->truesize -= delta; 875 876 return skb; 877 } 878 879 static void netlink_rcv_wake(struct sock *sk) 880 { 881 struct netlink_sock *nlk = nlk_sk(sk); 882 883 if (skb_queue_empty(&sk->sk_receive_queue)) 884 clear_bit(0, &nlk->state); 885 if (!test_bit(0, &nlk->state)) 886 wake_up_interruptible(&nlk->wait); 887 } 888 889 static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb) 890 { 891 int ret; 892 struct netlink_sock *nlk = nlk_sk(sk); 893 894 ret = -ECONNREFUSED; 895 if (nlk->netlink_rcv != NULL) { 896 ret = skb->len; 897 skb_set_owner_r(skb, sk); 898 nlk->netlink_rcv(skb); 899 } 900 kfree_skb(skb); 901 sock_put(sk); 902 return ret; 903 } 904 905 int netlink_unicast(struct sock *ssk, struct sk_buff *skb, 906 u32 pid, int nonblock) 907 { 908 struct sock *sk; 909 int err; 910 long timeo; 911 912 skb = netlink_trim(skb, gfp_any()); 913 914 timeo = sock_sndtimeo(ssk, nonblock); 915 retry: 916 sk = netlink_getsockbypid(ssk, pid); 917 if (IS_ERR(sk)) { 918 kfree_skb(skb); 919 return PTR_ERR(sk); 920 } 921 if (netlink_is_kernel(sk)) 922 return netlink_unicast_kernel(sk, skb); 923 924 if (sk_filter(sk, skb)) { 925 err = skb->len; 926 kfree_skb(skb); 927 sock_put(sk); 928 return err; 929 } 930 931 err = netlink_attachskb(sk, skb, &timeo, ssk); 932 if (err == 1) 933 goto retry; 934 if (err) 935 return err; 936 937 return netlink_sendskb(sk, skb); 938 } 939 EXPORT_SYMBOL(netlink_unicast); 940 941 int netlink_has_listeners(struct sock *sk, unsigned int group) 942 { 943 int res = 0; 944 struct listeners *listeners; 945 946 BUG_ON(!netlink_is_kernel(sk)); 947 948 rcu_read_lock(); 949 listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners); 950 951 if (group - 1 < nl_table[sk->sk_protocol].groups) 952 res = test_bit(group - 1, listeners->masks); 953 954 rcu_read_unlock(); 955 956 return res; 957 } 958 EXPORT_SYMBOL_GPL(netlink_has_listeners); 959 960 static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb) 961 { 962 struct netlink_sock *nlk = nlk_sk(sk); 963 964 if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && 965 !test_bit(0, &nlk->state)) { 966 skb_set_owner_r(skb, sk); 967 __netlink_sendskb(sk, skb); 968 return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1); 969 } 970 return -1; 971 } 972 973 struct netlink_broadcast_data { 974 struct sock *exclude_sk; 975 struct net *net; 976 u32 pid; 977 u32 group; 978 int failure; 979 int delivery_failure; 980 int congested; 981 int delivered; 982 gfp_t allocation; 983 struct sk_buff *skb, *skb2; 984 int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data); 985 void *tx_data; 986 }; 987 988 static int do_one_broadcast(struct sock *sk, 989 struct netlink_broadcast_data *p) 990 { 991 struct netlink_sock *nlk = nlk_sk(sk); 992 int val; 993 994 if (p->exclude_sk == sk) 995 goto out; 996 997 if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups || 998 !test_bit(p->group - 1, nlk->groups)) 999 goto out; 1000 1001 if (!net_eq(sock_net(sk), p->net)) 1002 goto out; 1003 1004 if (p->failure) { 1005 netlink_overrun(sk); 1006 goto out; 1007 } 1008 1009 sock_hold(sk); 1010 if (p->skb2 == NULL) { 1011 if (skb_shared(p->skb)) { 1012 p->skb2 = skb_clone(p->skb, p->allocation); 1013 } else { 1014 p->skb2 = skb_get(p->skb); 1015 /* 1016 * skb ownership may have been set when 1017 * delivered to a previous socket. 1018 */ 1019 skb_orphan(p->skb2); 1020 } 1021 } 1022 if (p->skb2 == NULL) { 1023 netlink_overrun(sk); 1024 /* Clone failed. Notify ALL listeners. */ 1025 p->failure = 1; 1026 if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) 1027 p->delivery_failure = 1; 1028 } else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) { 1029 kfree_skb(p->skb2); 1030 p->skb2 = NULL; 1031 } else if (sk_filter(sk, p->skb2)) { 1032 kfree_skb(p->skb2); 1033 p->skb2 = NULL; 1034 } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) { 1035 netlink_overrun(sk); 1036 if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) 1037 p->delivery_failure = 1; 1038 } else { 1039 p->congested |= val; 1040 p->delivered = 1; 1041 p->skb2 = NULL; 1042 } 1043 sock_put(sk); 1044 1045 out: 1046 return 0; 1047 } 1048 1049 int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 pid, 1050 u32 group, gfp_t allocation, 1051 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), 1052 void *filter_data) 1053 { 1054 struct net *net = sock_net(ssk); 1055 struct netlink_broadcast_data info; 1056 struct hlist_node *node; 1057 struct sock *sk; 1058 1059 skb = netlink_trim(skb, allocation); 1060 1061 info.exclude_sk = ssk; 1062 info.net = net; 1063 info.pid = pid; 1064 info.group = group; 1065 info.failure = 0; 1066 info.delivery_failure = 0; 1067 info.congested = 0; 1068 info.delivered = 0; 1069 info.allocation = allocation; 1070 info.skb = skb; 1071 info.skb2 = NULL; 1072 info.tx_filter = filter; 1073 info.tx_data = filter_data; 1074 1075 /* While we sleep in clone, do not allow to change socket list */ 1076 1077 netlink_lock_table(); 1078 1079 sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list) 1080 do_one_broadcast(sk, &info); 1081 1082 consume_skb(skb); 1083 1084 netlink_unlock_table(); 1085 1086 if (info.delivery_failure) { 1087 kfree_skb(info.skb2); 1088 return -ENOBUFS; 1089 } else 1090 consume_skb(info.skb2); 1091 1092 if (info.delivered) { 1093 if (info.congested && (allocation & __GFP_WAIT)) 1094 yield(); 1095 return 0; 1096 } 1097 return -ESRCH; 1098 } 1099 EXPORT_SYMBOL(netlink_broadcast_filtered); 1100 1101 int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid, 1102 u32 group, gfp_t allocation) 1103 { 1104 return netlink_broadcast_filtered(ssk, skb, pid, group, allocation, 1105 NULL, NULL); 1106 } 1107 EXPORT_SYMBOL(netlink_broadcast); 1108 1109 struct netlink_set_err_data { 1110 struct sock *exclude_sk; 1111 u32 pid; 1112 u32 group; 1113 int code; 1114 }; 1115 1116 static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p) 1117 { 1118 struct netlink_sock *nlk = nlk_sk(sk); 1119 int ret = 0; 1120 1121 if (sk == p->exclude_sk) 1122 goto out; 1123 1124 if (!net_eq(sock_net(sk), sock_net(p->exclude_sk))) 1125 goto out; 1126 1127 if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups || 1128 !test_bit(p->group - 1, nlk->groups)) 1129 goto out; 1130 1131 if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) { 1132 ret = 1; 1133 goto out; 1134 } 1135 1136 sk->sk_err = p->code; 1137 sk->sk_error_report(sk); 1138 out: 1139 return ret; 1140 } 1141 1142 /** 1143 * netlink_set_err - report error to broadcast listeners 1144 * @ssk: the kernel netlink socket, as returned by netlink_kernel_create() 1145 * @pid: the PID of a process that we want to skip (if any) 1146 * @groups: the broadcast group that will notice the error 1147 * @code: error code, must be negative (as usual in kernelspace) 1148 * 1149 * This function returns the number of broadcast listeners that have set the 1150 * NETLINK_RECV_NO_ENOBUFS socket option. 1151 */ 1152 int netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code) 1153 { 1154 struct netlink_set_err_data info; 1155 struct hlist_node *node; 1156 struct sock *sk; 1157 int ret = 0; 1158 1159 info.exclude_sk = ssk; 1160 info.pid = pid; 1161 info.group = group; 1162 /* sk->sk_err wants a positive error value */ 1163 info.code = -code; 1164 1165 read_lock(&nl_table_lock); 1166 1167 sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list) 1168 ret += do_one_set_err(sk, &info); 1169 1170 read_unlock(&nl_table_lock); 1171 return ret; 1172 } 1173 EXPORT_SYMBOL(netlink_set_err); 1174 1175 /* must be called with netlink table grabbed */ 1176 static void netlink_update_socket_mc(struct netlink_sock *nlk, 1177 unsigned int group, 1178 int is_new) 1179 { 1180 int old, new = !!is_new, subscriptions; 1181 1182 old = test_bit(group - 1, nlk->groups); 1183 subscriptions = nlk->subscriptions - old + new; 1184 if (new) 1185 __set_bit(group - 1, nlk->groups); 1186 else 1187 __clear_bit(group - 1, nlk->groups); 1188 netlink_update_subscriptions(&nlk->sk, subscriptions); 1189 netlink_update_listeners(&nlk->sk); 1190 } 1191 1192 static int netlink_setsockopt(struct socket *sock, int level, int optname, 1193 char __user *optval, unsigned int optlen) 1194 { 1195 struct sock *sk = sock->sk; 1196 struct netlink_sock *nlk = nlk_sk(sk); 1197 unsigned int val = 0; 1198 int err; 1199 1200 if (level != SOL_NETLINK) 1201 return -ENOPROTOOPT; 1202 1203 if (optlen >= sizeof(int) && 1204 get_user(val, (unsigned int __user *)optval)) 1205 return -EFAULT; 1206 1207 switch (optname) { 1208 case NETLINK_PKTINFO: 1209 if (val) 1210 nlk->flags |= NETLINK_RECV_PKTINFO; 1211 else 1212 nlk->flags &= ~NETLINK_RECV_PKTINFO; 1213 err = 0; 1214 break; 1215 case NETLINK_ADD_MEMBERSHIP: 1216 case NETLINK_DROP_MEMBERSHIP: { 1217 if (!netlink_capable(sock, NL_NONROOT_RECV)) 1218 return -EPERM; 1219 err = netlink_realloc_groups(sk); 1220 if (err) 1221 return err; 1222 if (!val || val - 1 >= nlk->ngroups) 1223 return -EINVAL; 1224 netlink_table_grab(); 1225 netlink_update_socket_mc(nlk, val, 1226 optname == NETLINK_ADD_MEMBERSHIP); 1227 netlink_table_ungrab(); 1228 err = 0; 1229 break; 1230 } 1231 case NETLINK_BROADCAST_ERROR: 1232 if (val) 1233 nlk->flags |= NETLINK_BROADCAST_SEND_ERROR; 1234 else 1235 nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR; 1236 err = 0; 1237 break; 1238 case NETLINK_NO_ENOBUFS: 1239 if (val) { 1240 nlk->flags |= NETLINK_RECV_NO_ENOBUFS; 1241 clear_bit(0, &nlk->state); 1242 wake_up_interruptible(&nlk->wait); 1243 } else 1244 nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS; 1245 err = 0; 1246 break; 1247 default: 1248 err = -ENOPROTOOPT; 1249 } 1250 return err; 1251 } 1252 1253 static int netlink_getsockopt(struct socket *sock, int level, int optname, 1254 char __user *optval, int __user *optlen) 1255 { 1256 struct sock *sk = sock->sk; 1257 struct netlink_sock *nlk = nlk_sk(sk); 1258 int len, val, err; 1259 1260 if (level != SOL_NETLINK) 1261 return -ENOPROTOOPT; 1262 1263 if (get_user(len, optlen)) 1264 return -EFAULT; 1265 if (len < 0) 1266 return -EINVAL; 1267 1268 switch (optname) { 1269 case NETLINK_PKTINFO: 1270 if (len < sizeof(int)) 1271 return -EINVAL; 1272 len = sizeof(int); 1273 val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0; 1274 if (put_user(len, optlen) || 1275 put_user(val, optval)) 1276 return -EFAULT; 1277 err = 0; 1278 break; 1279 case NETLINK_BROADCAST_ERROR: 1280 if (len < sizeof(int)) 1281 return -EINVAL; 1282 len = sizeof(int); 1283 val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0; 1284 if (put_user(len, optlen) || 1285 put_user(val, optval)) 1286 return -EFAULT; 1287 err = 0; 1288 break; 1289 case NETLINK_NO_ENOBUFS: 1290 if (len < sizeof(int)) 1291 return -EINVAL; 1292 len = sizeof(int); 1293 val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0; 1294 if (put_user(len, optlen) || 1295 put_user(val, optval)) 1296 return -EFAULT; 1297 err = 0; 1298 break; 1299 default: 1300 err = -ENOPROTOOPT; 1301 } 1302 return err; 1303 } 1304 1305 static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) 1306 { 1307 struct nl_pktinfo info; 1308 1309 info.group = NETLINK_CB(skb).dst_group; 1310 put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info); 1311 } 1312 1313 static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, 1314 struct msghdr *msg, size_t len) 1315 { 1316 struct sock_iocb *siocb = kiocb_to_siocb(kiocb); 1317 struct sock *sk = sock->sk; 1318 struct netlink_sock *nlk = nlk_sk(sk); 1319 struct sockaddr_nl *addr = msg->msg_name; 1320 u32 dst_pid; 1321 u32 dst_group; 1322 struct sk_buff *skb; 1323 int err; 1324 struct scm_cookie scm; 1325 1326 if (msg->msg_flags&MSG_OOB) 1327 return -EOPNOTSUPP; 1328 1329 if (NULL == siocb->scm) 1330 siocb->scm = &scm; 1331 1332 err = scm_send(sock, msg, siocb->scm); 1333 if (err < 0) 1334 return err; 1335 1336 if (msg->msg_namelen) { 1337 err = -EINVAL; 1338 if (addr->nl_family != AF_NETLINK) 1339 goto out; 1340 dst_pid = addr->nl_pid; 1341 dst_group = ffs(addr->nl_groups); 1342 err = -EPERM; 1343 if (dst_group && !netlink_capable(sock, NL_NONROOT_SEND)) 1344 goto out; 1345 } else { 1346 dst_pid = nlk->dst_pid; 1347 dst_group = nlk->dst_group; 1348 } 1349 1350 if (!nlk->pid) { 1351 err = netlink_autobind(sock); 1352 if (err) 1353 goto out; 1354 } 1355 1356 err = -EMSGSIZE; 1357 if (len > sk->sk_sndbuf - 32) 1358 goto out; 1359 err = -ENOBUFS; 1360 skb = alloc_skb(len, GFP_KERNEL); 1361 if (skb == NULL) 1362 goto out; 1363 1364 NETLINK_CB(skb).pid = nlk->pid; 1365 NETLINK_CB(skb).dst_group = dst_group; 1366 memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred)); 1367 1368 err = -EFAULT; 1369 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) { 1370 kfree_skb(skb); 1371 goto out; 1372 } 1373 1374 err = security_netlink_send(sk, skb); 1375 if (err) { 1376 kfree_skb(skb); 1377 goto out; 1378 } 1379 1380 if (dst_group) { 1381 atomic_inc(&skb->users); 1382 netlink_broadcast(sk, skb, dst_pid, dst_group, GFP_KERNEL); 1383 } 1384 err = netlink_unicast(sk, skb, dst_pid, msg->msg_flags&MSG_DONTWAIT); 1385 1386 out: 1387 scm_destroy(siocb->scm); 1388 return err; 1389 } 1390 1391 static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, 1392 struct msghdr *msg, size_t len, 1393 int flags) 1394 { 1395 struct sock_iocb *siocb = kiocb_to_siocb(kiocb); 1396 struct scm_cookie scm; 1397 struct sock *sk = sock->sk; 1398 struct netlink_sock *nlk = nlk_sk(sk); 1399 int noblock = flags&MSG_DONTWAIT; 1400 size_t copied; 1401 struct sk_buff *skb, *data_skb; 1402 int err, ret; 1403 1404 if (flags&MSG_OOB) 1405 return -EOPNOTSUPP; 1406 1407 copied = 0; 1408 1409 skb = skb_recv_datagram(sk, flags, noblock, &err); 1410 if (skb == NULL) 1411 goto out; 1412 1413 data_skb = skb; 1414 1415 #ifdef CONFIG_COMPAT_NETLINK_MESSAGES 1416 if (unlikely(skb_shinfo(skb)->frag_list)) { 1417 /* 1418 * If this skb has a frag_list, then here that means that we 1419 * will have to use the frag_list skb's data for compat tasks 1420 * and the regular skb's data for normal (non-compat) tasks. 1421 * 1422 * If we need to send the compat skb, assign it to the 1423 * 'data_skb' variable so that it will be used below for data 1424 * copying. We keep 'skb' for everything else, including 1425 * freeing both later. 1426 */ 1427 if (flags & MSG_CMSG_COMPAT) 1428 data_skb = skb_shinfo(skb)->frag_list; 1429 } 1430 #endif 1431 1432 msg->msg_namelen = 0; 1433 1434 copied = data_skb->len; 1435 if (len < copied) { 1436 msg->msg_flags |= MSG_TRUNC; 1437 copied = len; 1438 } 1439 1440 skb_reset_transport_header(data_skb); 1441 err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied); 1442 1443 if (msg->msg_name) { 1444 struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name; 1445 addr->nl_family = AF_NETLINK; 1446 addr->nl_pad = 0; 1447 addr->nl_pid = NETLINK_CB(skb).pid; 1448 addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group); 1449 msg->msg_namelen = sizeof(*addr); 1450 } 1451 1452 if (nlk->flags & NETLINK_RECV_PKTINFO) 1453 netlink_cmsg_recv_pktinfo(msg, skb); 1454 1455 if (NULL == siocb->scm) { 1456 memset(&scm, 0, sizeof(scm)); 1457 siocb->scm = &scm; 1458 } 1459 siocb->scm->creds = *NETLINK_CREDS(skb); 1460 if (flags & MSG_TRUNC) 1461 copied = data_skb->len; 1462 1463 skb_free_datagram(sk, skb); 1464 1465 if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) { 1466 ret = netlink_dump(sk); 1467 if (ret) { 1468 sk->sk_err = ret; 1469 sk->sk_error_report(sk); 1470 } 1471 } 1472 1473 scm_recv(sock, msg, siocb->scm, flags); 1474 out: 1475 netlink_rcv_wake(sk); 1476 return err ? : copied; 1477 } 1478 1479 static void netlink_data_ready(struct sock *sk, int len) 1480 { 1481 BUG(); 1482 } 1483 1484 /* 1485 * We export these functions to other modules. They provide a 1486 * complete set of kernel non-blocking support for message 1487 * queueing. 1488 */ 1489 1490 struct sock * 1491 netlink_kernel_create(struct net *net, int unit, unsigned int groups, 1492 void (*input)(struct sk_buff *skb), 1493 struct mutex *cb_mutex, struct module *module) 1494 { 1495 struct socket *sock; 1496 struct sock *sk; 1497 struct netlink_sock *nlk; 1498 struct listeners *listeners = NULL; 1499 1500 BUG_ON(!nl_table); 1501 1502 if (unit < 0 || unit >= MAX_LINKS) 1503 return NULL; 1504 1505 if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) 1506 return NULL; 1507 1508 /* 1509 * We have to just have a reference on the net from sk, but don't 1510 * get_net it. Besides, we cannot get and then put the net here. 1511 * So we create one inside init_net and the move it to net. 1512 */ 1513 1514 if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0) 1515 goto out_sock_release_nosk; 1516 1517 sk = sock->sk; 1518 sk_change_net(sk, net); 1519 1520 if (groups < 32) 1521 groups = 32; 1522 1523 listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); 1524 if (!listeners) 1525 goto out_sock_release; 1526 1527 sk->sk_data_ready = netlink_data_ready; 1528 if (input) 1529 nlk_sk(sk)->netlink_rcv = input; 1530 1531 if (netlink_insert(sk, net, 0)) 1532 goto out_sock_release; 1533 1534 nlk = nlk_sk(sk); 1535 nlk->flags |= NETLINK_KERNEL_SOCKET; 1536 1537 netlink_table_grab(); 1538 if (!nl_table[unit].registered) { 1539 nl_table[unit].groups = groups; 1540 rcu_assign_pointer(nl_table[unit].listeners, listeners); 1541 nl_table[unit].cb_mutex = cb_mutex; 1542 nl_table[unit].module = module; 1543 nl_table[unit].registered = 1; 1544 } else { 1545 kfree(listeners); 1546 nl_table[unit].registered++; 1547 } 1548 netlink_table_ungrab(); 1549 return sk; 1550 1551 out_sock_release: 1552 kfree(listeners); 1553 netlink_kernel_release(sk); 1554 return NULL; 1555 1556 out_sock_release_nosk: 1557 sock_release(sock); 1558 return NULL; 1559 } 1560 EXPORT_SYMBOL(netlink_kernel_create); 1561 1562 1563 void 1564 netlink_kernel_release(struct sock *sk) 1565 { 1566 sk_release_kernel(sk); 1567 } 1568 EXPORT_SYMBOL(netlink_kernel_release); 1569 1570 int __netlink_change_ngroups(struct sock *sk, unsigned int groups) 1571 { 1572 struct listeners *new, *old; 1573 struct netlink_table *tbl = &nl_table[sk->sk_protocol]; 1574 1575 if (groups < 32) 1576 groups = 32; 1577 1578 if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) { 1579 new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC); 1580 if (!new) 1581 return -ENOMEM; 1582 old = rcu_dereference_protected(tbl->listeners, 1); 1583 memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups)); 1584 rcu_assign_pointer(tbl->listeners, new); 1585 1586 kfree_rcu(old, rcu); 1587 } 1588 tbl->groups = groups; 1589 1590 return 0; 1591 } 1592 1593 /** 1594 * netlink_change_ngroups - change number of multicast groups 1595 * 1596 * This changes the number of multicast groups that are available 1597 * on a certain netlink family. Note that it is not possible to 1598 * change the number of groups to below 32. Also note that it does 1599 * not implicitly call netlink_clear_multicast_users() when the 1600 * number of groups is reduced. 1601 * 1602 * @sk: The kernel netlink socket, as returned by netlink_kernel_create(). 1603 * @groups: The new number of groups. 1604 */ 1605 int netlink_change_ngroups(struct sock *sk, unsigned int groups) 1606 { 1607 int err; 1608 1609 netlink_table_grab(); 1610 err = __netlink_change_ngroups(sk, groups); 1611 netlink_table_ungrab(); 1612 1613 return err; 1614 } 1615 1616 void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) 1617 { 1618 struct sock *sk; 1619 struct hlist_node *node; 1620 struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; 1621 1622 sk_for_each_bound(sk, node, &tbl->mc_list) 1623 netlink_update_socket_mc(nlk_sk(sk), group, 0); 1624 } 1625 1626 /** 1627 * netlink_clear_multicast_users - kick off multicast listeners 1628 * 1629 * This function removes all listeners from the given group. 1630 * @ksk: The kernel netlink socket, as returned by 1631 * netlink_kernel_create(). 1632 * @group: The multicast group to clear. 1633 */ 1634 void netlink_clear_multicast_users(struct sock *ksk, unsigned int group) 1635 { 1636 netlink_table_grab(); 1637 __netlink_clear_multicast_users(ksk, group); 1638 netlink_table_ungrab(); 1639 } 1640 1641 void netlink_set_nonroot(int protocol, unsigned int flags) 1642 { 1643 if ((unsigned int)protocol < MAX_LINKS) 1644 nl_table[protocol].nl_nonroot = flags; 1645 } 1646 EXPORT_SYMBOL(netlink_set_nonroot); 1647 1648 static void netlink_destroy_callback(struct netlink_callback *cb) 1649 { 1650 kfree_skb(cb->skb); 1651 kfree(cb); 1652 } 1653 1654 struct nlmsghdr * 1655 __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags) 1656 { 1657 struct nlmsghdr *nlh; 1658 int size = NLMSG_LENGTH(len); 1659 1660 nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size)); 1661 nlh->nlmsg_type = type; 1662 nlh->nlmsg_len = size; 1663 nlh->nlmsg_flags = flags; 1664 nlh->nlmsg_pid = pid; 1665 nlh->nlmsg_seq = seq; 1666 if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0) 1667 memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size); 1668 return nlh; 1669 } 1670 EXPORT_SYMBOL(__nlmsg_put); 1671 1672 /* 1673 * It looks a bit ugly. 1674 * It would be better to create kernel thread. 1675 */ 1676 1677 static int netlink_dump(struct sock *sk) 1678 { 1679 struct netlink_sock *nlk = nlk_sk(sk); 1680 struct netlink_callback *cb; 1681 struct sk_buff *skb = NULL; 1682 struct nlmsghdr *nlh; 1683 int len, err = -ENOBUFS; 1684 int alloc_size; 1685 1686 mutex_lock(nlk->cb_mutex); 1687 1688 cb = nlk->cb; 1689 if (cb == NULL) { 1690 err = -EINVAL; 1691 goto errout_skb; 1692 } 1693 1694 alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE); 1695 1696 skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL); 1697 if (!skb) 1698 goto errout_skb; 1699 1700 len = cb->dump(skb, cb); 1701 1702 if (len > 0) { 1703 mutex_unlock(nlk->cb_mutex); 1704 1705 if (sk_filter(sk, skb)) 1706 kfree_skb(skb); 1707 else 1708 __netlink_sendskb(sk, skb); 1709 return 0; 1710 } 1711 1712 nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); 1713 if (!nlh) 1714 goto errout_skb; 1715 1716 nl_dump_check_consistent(cb, nlh); 1717 1718 memcpy(nlmsg_data(nlh), &len, sizeof(len)); 1719 1720 if (sk_filter(sk, skb)) 1721 kfree_skb(skb); 1722 else 1723 __netlink_sendskb(sk, skb); 1724 1725 if (cb->done) 1726 cb->done(cb); 1727 nlk->cb = NULL; 1728 mutex_unlock(nlk->cb_mutex); 1729 1730 netlink_destroy_callback(cb); 1731 return 0; 1732 1733 errout_skb: 1734 mutex_unlock(nlk->cb_mutex); 1735 kfree_skb(skb); 1736 return err; 1737 } 1738 1739 int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, 1740 const struct nlmsghdr *nlh, 1741 struct netlink_dump_control *control) 1742 { 1743 struct netlink_callback *cb; 1744 struct sock *sk; 1745 struct netlink_sock *nlk; 1746 int ret; 1747 1748 cb = kzalloc(sizeof(*cb), GFP_KERNEL); 1749 if (cb == NULL) 1750 return -ENOBUFS; 1751 1752 cb->dump = control->dump; 1753 cb->done = control->done; 1754 cb->nlh = nlh; 1755 cb->data = control->data; 1756 cb->min_dump_alloc = control->min_dump_alloc; 1757 atomic_inc(&skb->users); 1758 cb->skb = skb; 1759 1760 sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).pid); 1761 if (sk == NULL) { 1762 netlink_destroy_callback(cb); 1763 return -ECONNREFUSED; 1764 } 1765 nlk = nlk_sk(sk); 1766 /* A dump is in progress... */ 1767 mutex_lock(nlk->cb_mutex); 1768 if (nlk->cb) { 1769 mutex_unlock(nlk->cb_mutex); 1770 netlink_destroy_callback(cb); 1771 sock_put(sk); 1772 return -EBUSY; 1773 } 1774 nlk->cb = cb; 1775 mutex_unlock(nlk->cb_mutex); 1776 1777 ret = netlink_dump(sk); 1778 1779 sock_put(sk); 1780 1781 if (ret) 1782 return ret; 1783 1784 /* We successfully started a dump, by returning -EINTR we 1785 * signal not to send ACK even if it was requested. 1786 */ 1787 return -EINTR; 1788 } 1789 EXPORT_SYMBOL(netlink_dump_start); 1790 1791 void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) 1792 { 1793 struct sk_buff *skb; 1794 struct nlmsghdr *rep; 1795 struct nlmsgerr *errmsg; 1796 size_t payload = sizeof(*errmsg); 1797 1798 /* error messages get the original request appened */ 1799 if (err) 1800 payload += nlmsg_len(nlh); 1801 1802 skb = nlmsg_new(payload, GFP_KERNEL); 1803 if (!skb) { 1804 struct sock *sk; 1805 1806 sk = netlink_lookup(sock_net(in_skb->sk), 1807 in_skb->sk->sk_protocol, 1808 NETLINK_CB(in_skb).pid); 1809 if (sk) { 1810 sk->sk_err = ENOBUFS; 1811 sk->sk_error_report(sk); 1812 sock_put(sk); 1813 } 1814 return; 1815 } 1816 1817 rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, 1818 NLMSG_ERROR, payload, 0); 1819 errmsg = nlmsg_data(rep); 1820 errmsg->error = err; 1821 memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh)); 1822 netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT); 1823 } 1824 EXPORT_SYMBOL(netlink_ack); 1825 1826 int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, 1827 struct nlmsghdr *)) 1828 { 1829 struct nlmsghdr *nlh; 1830 int err; 1831 1832 while (skb->len >= nlmsg_total_size(0)) { 1833 int msglen; 1834 1835 nlh = nlmsg_hdr(skb); 1836 err = 0; 1837 1838 if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) 1839 return 0; 1840 1841 /* Only requests are handled by the kernel */ 1842 if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) 1843 goto ack; 1844 1845 /* Skip control messages */ 1846 if (nlh->nlmsg_type < NLMSG_MIN_TYPE) 1847 goto ack; 1848 1849 err = cb(skb, nlh); 1850 if (err == -EINTR) 1851 goto skip; 1852 1853 ack: 1854 if (nlh->nlmsg_flags & NLM_F_ACK || err) 1855 netlink_ack(skb, nlh, err); 1856 1857 skip: 1858 msglen = NLMSG_ALIGN(nlh->nlmsg_len); 1859 if (msglen > skb->len) 1860 msglen = skb->len; 1861 skb_pull(skb, msglen); 1862 } 1863 1864 return 0; 1865 } 1866 EXPORT_SYMBOL(netlink_rcv_skb); 1867 1868 /** 1869 * nlmsg_notify - send a notification netlink message 1870 * @sk: netlink socket to use 1871 * @skb: notification message 1872 * @pid: destination netlink pid for reports or 0 1873 * @group: destination multicast group or 0 1874 * @report: 1 to report back, 0 to disable 1875 * @flags: allocation flags 1876 */ 1877 int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid, 1878 unsigned int group, int report, gfp_t flags) 1879 { 1880 int err = 0; 1881 1882 if (group) { 1883 int exclude_pid = 0; 1884 1885 if (report) { 1886 atomic_inc(&skb->users); 1887 exclude_pid = pid; 1888 } 1889 1890 /* errors reported via destination sk->sk_err, but propagate 1891 * delivery errors if NETLINK_BROADCAST_ERROR flag is set */ 1892 err = nlmsg_multicast(sk, skb, exclude_pid, group, flags); 1893 } 1894 1895 if (report) { 1896 int err2; 1897 1898 err2 = nlmsg_unicast(sk, skb, pid); 1899 if (!err || err == -ESRCH) 1900 err = err2; 1901 } 1902 1903 return err; 1904 } 1905 EXPORT_SYMBOL(nlmsg_notify); 1906 1907 #ifdef CONFIG_PROC_FS 1908 struct nl_seq_iter { 1909 struct seq_net_private p; 1910 int link; 1911 int hash_idx; 1912 }; 1913 1914 static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos) 1915 { 1916 struct nl_seq_iter *iter = seq->private; 1917 int i, j; 1918 struct sock *s; 1919 struct hlist_node *node; 1920 loff_t off = 0; 1921 1922 for (i = 0; i < MAX_LINKS; i++) { 1923 struct nl_pid_hash *hash = &nl_table[i].hash; 1924 1925 for (j = 0; j <= hash->mask; j++) { 1926 sk_for_each(s, node, &hash->table[j]) { 1927 if (sock_net(s) != seq_file_net(seq)) 1928 continue; 1929 if (off == pos) { 1930 iter->link = i; 1931 iter->hash_idx = j; 1932 return s; 1933 } 1934 ++off; 1935 } 1936 } 1937 } 1938 return NULL; 1939 } 1940 1941 static void *netlink_seq_start(struct seq_file *seq, loff_t *pos) 1942 __acquires(nl_table_lock) 1943 { 1944 read_lock(&nl_table_lock); 1945 return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN; 1946 } 1947 1948 static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1949 { 1950 struct sock *s; 1951 struct nl_seq_iter *iter; 1952 int i, j; 1953 1954 ++*pos; 1955 1956 if (v == SEQ_START_TOKEN) 1957 return netlink_seq_socket_idx(seq, 0); 1958 1959 iter = seq->private; 1960 s = v; 1961 do { 1962 s = sk_next(s); 1963 } while (s && sock_net(s) != seq_file_net(seq)); 1964 if (s) 1965 return s; 1966 1967 i = iter->link; 1968 j = iter->hash_idx + 1; 1969 1970 do { 1971 struct nl_pid_hash *hash = &nl_table[i].hash; 1972 1973 for (; j <= hash->mask; j++) { 1974 s = sk_head(&hash->table[j]); 1975 while (s && sock_net(s) != seq_file_net(seq)) 1976 s = sk_next(s); 1977 if (s) { 1978 iter->link = i; 1979 iter->hash_idx = j; 1980 return s; 1981 } 1982 } 1983 1984 j = 0; 1985 } while (++i < MAX_LINKS); 1986 1987 return NULL; 1988 } 1989 1990 static void netlink_seq_stop(struct seq_file *seq, void *v) 1991 __releases(nl_table_lock) 1992 { 1993 read_unlock(&nl_table_lock); 1994 } 1995 1996 1997 static int netlink_seq_show(struct seq_file *seq, void *v) 1998 { 1999 if (v == SEQ_START_TOKEN) 2000 seq_puts(seq, 2001 "sk Eth Pid Groups " 2002 "Rmem Wmem Dump Locks Drops Inode\n"); 2003 else { 2004 struct sock *s = v; 2005 struct netlink_sock *nlk = nlk_sk(s); 2006 2007 seq_printf(seq, "%pK %-3d %-6d %08x %-8d %-8d %pK %-8d %-8d %-8lu\n", 2008 s, 2009 s->sk_protocol, 2010 nlk->pid, 2011 nlk->groups ? (u32)nlk->groups[0] : 0, 2012 sk_rmem_alloc_get(s), 2013 sk_wmem_alloc_get(s), 2014 nlk->cb, 2015 atomic_read(&s->sk_refcnt), 2016 atomic_read(&s->sk_drops), 2017 sock_i_ino(s) 2018 ); 2019 2020 } 2021 return 0; 2022 } 2023 2024 static const struct seq_operations netlink_seq_ops = { 2025 .start = netlink_seq_start, 2026 .next = netlink_seq_next, 2027 .stop = netlink_seq_stop, 2028 .show = netlink_seq_show, 2029 }; 2030 2031 2032 static int netlink_seq_open(struct inode *inode, struct file *file) 2033 { 2034 return seq_open_net(inode, file, &netlink_seq_ops, 2035 sizeof(struct nl_seq_iter)); 2036 } 2037 2038 static const struct file_operations netlink_seq_fops = { 2039 .owner = THIS_MODULE, 2040 .open = netlink_seq_open, 2041 .read = seq_read, 2042 .llseek = seq_lseek, 2043 .release = seq_release_net, 2044 }; 2045 2046 #endif 2047 2048 int netlink_register_notifier(struct notifier_block *nb) 2049 { 2050 return atomic_notifier_chain_register(&netlink_chain, nb); 2051 } 2052 EXPORT_SYMBOL(netlink_register_notifier); 2053 2054 int netlink_unregister_notifier(struct notifier_block *nb) 2055 { 2056 return atomic_notifier_chain_unregister(&netlink_chain, nb); 2057 } 2058 EXPORT_SYMBOL(netlink_unregister_notifier); 2059 2060 static const struct proto_ops netlink_ops = { 2061 .family = PF_NETLINK, 2062 .owner = THIS_MODULE, 2063 .release = netlink_release, 2064 .bind = netlink_bind, 2065 .connect = netlink_connect, 2066 .socketpair = sock_no_socketpair, 2067 .accept = sock_no_accept, 2068 .getname = netlink_getname, 2069 .poll = datagram_poll, 2070 .ioctl = sock_no_ioctl, 2071 .listen = sock_no_listen, 2072 .shutdown = sock_no_shutdown, 2073 .setsockopt = netlink_setsockopt, 2074 .getsockopt = netlink_getsockopt, 2075 .sendmsg = netlink_sendmsg, 2076 .recvmsg = netlink_recvmsg, 2077 .mmap = sock_no_mmap, 2078 .sendpage = sock_no_sendpage, 2079 }; 2080 2081 static const struct net_proto_family netlink_family_ops = { 2082 .family = PF_NETLINK, 2083 .create = netlink_create, 2084 .owner = THIS_MODULE, /* for consistency 8) */ 2085 }; 2086 2087 static int __net_init netlink_net_init(struct net *net) 2088 { 2089 #ifdef CONFIG_PROC_FS 2090 if (!proc_net_fops_create(net, "netlink", 0, &netlink_seq_fops)) 2091 return -ENOMEM; 2092 #endif 2093 return 0; 2094 } 2095 2096 static void __net_exit netlink_net_exit(struct net *net) 2097 { 2098 #ifdef CONFIG_PROC_FS 2099 proc_net_remove(net, "netlink"); 2100 #endif 2101 } 2102 2103 static void __init netlink_add_usersock_entry(void) 2104 { 2105 struct listeners *listeners; 2106 int groups = 32; 2107 2108 listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); 2109 if (!listeners) 2110 panic("netlink_add_usersock_entry: Cannot allocate listeners\n"); 2111 2112 netlink_table_grab(); 2113 2114 nl_table[NETLINK_USERSOCK].groups = groups; 2115 rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners); 2116 nl_table[NETLINK_USERSOCK].module = THIS_MODULE; 2117 nl_table[NETLINK_USERSOCK].registered = 1; 2118 2119 netlink_table_ungrab(); 2120 } 2121 2122 static struct pernet_operations __net_initdata netlink_net_ops = { 2123 .init = netlink_net_init, 2124 .exit = netlink_net_exit, 2125 }; 2126 2127 static int __init netlink_proto_init(void) 2128 { 2129 struct sk_buff *dummy_skb; 2130 int i; 2131 unsigned long limit; 2132 unsigned int order; 2133 int err = proto_register(&netlink_proto, 0); 2134 2135 if (err != 0) 2136 goto out; 2137 2138 BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb)); 2139 2140 nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL); 2141 if (!nl_table) 2142 goto panic; 2143 2144 if (totalram_pages >= (128 * 1024)) 2145 limit = totalram_pages >> (21 - PAGE_SHIFT); 2146 else 2147 limit = totalram_pages >> (23 - PAGE_SHIFT); 2148 2149 order = get_bitmask_order(limit) - 1 + PAGE_SHIFT; 2150 limit = (1UL << order) / sizeof(struct hlist_head); 2151 order = get_bitmask_order(min(limit, (unsigned long)UINT_MAX)) - 1; 2152 2153 for (i = 0; i < MAX_LINKS; i++) { 2154 struct nl_pid_hash *hash = &nl_table[i].hash; 2155 2156 hash->table = nl_pid_hash_zalloc(1 * sizeof(*hash->table)); 2157 if (!hash->table) { 2158 while (i-- > 0) 2159 nl_pid_hash_free(nl_table[i].hash.table, 2160 1 * sizeof(*hash->table)); 2161 kfree(nl_table); 2162 goto panic; 2163 } 2164 hash->max_shift = order; 2165 hash->shift = 0; 2166 hash->mask = 0; 2167 hash->rehash_time = jiffies; 2168 } 2169 2170 netlink_add_usersock_entry(); 2171 2172 sock_register(&netlink_family_ops); 2173 register_pernet_subsys(&netlink_net_ops); 2174 /* The netlink device handler may be needed early. */ 2175 rtnetlink_init(); 2176 out: 2177 return err; 2178 panic: 2179 panic("netlink_init: Cannot allocate nl_table\n"); 2180 } 2181 2182 core_initcall(netlink_proto_init); 2183