1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ip6_flowlabel.c IPv6 flowlabel manager. 4 * 5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 6 */ 7 8 #include <linux/capability.h> 9 #include <linux/errno.h> 10 #include <linux/types.h> 11 #include <linux/socket.h> 12 #include <linux/net.h> 13 #include <linux/netdevice.h> 14 #include <linux/in6.h> 15 #include <linux/proc_fs.h> 16 #include <linux/seq_file.h> 17 #include <linux/slab.h> 18 #include <linux/export.h> 19 #include <linux/pid_namespace.h> 20 21 #include <net/net_namespace.h> 22 #include <net/sock.h> 23 24 #include <net/ipv6.h> 25 #include <net/rawv6.h> 26 #include <net/transp_v6.h> 27 28 #include <linux/uaccess.h> 29 30 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified 31 in old IPv6 RFC. Well, it was reasonable value. 32 */ 33 #define FL_MAX_LINGER 150 /* Maximal linger timeout */ 34 35 /* FL hash table */ 36 37 #define FL_MAX_PER_SOCK 32 38 #define FL_MAX_SIZE 4096 39 #define FL_HASH_MASK 255 40 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK) 41 42 static atomic_t fl_size = ATOMIC_INIT(0); 43 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1]; 44 45 static void ip6_fl_gc(struct timer_list *unused); 46 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc); 47 48 /* FL hash table lock: it protects only of GC */ 49 50 static DEFINE_SPINLOCK(ip6_fl_lock); 51 52 /* Big socket sock */ 53 54 static DEFINE_SPINLOCK(ip6_sk_fl_lock); 55 56 #define for_each_fl_rcu(hash, fl) \ 57 for (fl = rcu_dereference_bh(fl_ht[(hash)]); \ 58 fl != NULL; \ 59 fl = rcu_dereference_bh(fl->next)) 60 #define for_each_fl_continue_rcu(fl) \ 61 for (fl = rcu_dereference_bh(fl->next); \ 62 fl != NULL; \ 63 fl = rcu_dereference_bh(fl->next)) 64 65 #define for_each_sk_fl_rcu(np, sfl) \ 66 for (sfl = rcu_dereference_bh(np->ipv6_fl_list); \ 67 sfl != NULL; \ 68 sfl = rcu_dereference_bh(sfl->next)) 69 70 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label) 71 { 72 struct ip6_flowlabel *fl; 73 74 for_each_fl_rcu(FL_HASH(label), fl) { 75 if (fl->label == label && net_eq(fl->fl_net, net)) 76 return fl; 77 } 78 return NULL; 79 } 80 81 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) 82 { 83 struct ip6_flowlabel *fl; 84 85 rcu_read_lock_bh(); 86 fl = __fl_lookup(net, label); 87 if (fl && !atomic_inc_not_zero(&fl->users)) 88 fl = NULL; 89 rcu_read_unlock_bh(); 90 return fl; 91 } 92 93 static void fl_free_rcu(struct rcu_head *head) 94 { 95 struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu); 96 97 if (fl->share == IPV6_FL_S_PROCESS) 98 put_pid(fl->owner.pid); 99 kfree(fl->opt); 100 kfree(fl); 101 } 102 103 104 static void fl_free(struct ip6_flowlabel *fl) 105 { 106 if (fl) 107 call_rcu(&fl->rcu, fl_free_rcu); 108 } 109 110 static void fl_release(struct ip6_flowlabel *fl) 111 { 112 spin_lock_bh(&ip6_fl_lock); 113 114 fl->lastuse = jiffies; 115 if (atomic_dec_and_test(&fl->users)) { 116 unsigned long ttd = fl->lastuse + fl->linger; 117 if (time_after(ttd, fl->expires)) 118 fl->expires = ttd; 119 ttd = fl->expires; 120 if (fl->opt && fl->share == IPV6_FL_S_EXCL) { 121 struct ipv6_txoptions *opt = fl->opt; 122 fl->opt = NULL; 123 kfree(opt); 124 } 125 if (!timer_pending(&ip6_fl_gc_timer) || 126 time_after(ip6_fl_gc_timer.expires, ttd)) 127 mod_timer(&ip6_fl_gc_timer, ttd); 128 } 129 spin_unlock_bh(&ip6_fl_lock); 130 } 131 132 static void ip6_fl_gc(struct timer_list *unused) 133 { 134 int i; 135 unsigned long now = jiffies; 136 unsigned long sched = 0; 137 138 spin_lock(&ip6_fl_lock); 139 140 for (i = 0; i <= FL_HASH_MASK; i++) { 141 struct ip6_flowlabel *fl; 142 struct ip6_flowlabel __rcu **flp; 143 144 flp = &fl_ht[i]; 145 while ((fl = rcu_dereference_protected(*flp, 146 lockdep_is_held(&ip6_fl_lock))) != NULL) { 147 if (atomic_read(&fl->users) == 0) { 148 unsigned long ttd = fl->lastuse + fl->linger; 149 if (time_after(ttd, fl->expires)) 150 fl->expires = ttd; 151 ttd = fl->expires; 152 if (time_after_eq(now, ttd)) { 153 *flp = fl->next; 154 fl_free(fl); 155 atomic_dec(&fl_size); 156 continue; 157 } 158 if (!sched || time_before(ttd, sched)) 159 sched = ttd; 160 } 161 flp = &fl->next; 162 } 163 } 164 if (!sched && atomic_read(&fl_size)) 165 sched = now + FL_MAX_LINGER; 166 if (sched) { 167 mod_timer(&ip6_fl_gc_timer, sched); 168 } 169 spin_unlock(&ip6_fl_lock); 170 } 171 172 static void __net_exit ip6_fl_purge(struct net *net) 173 { 174 int i; 175 176 spin_lock_bh(&ip6_fl_lock); 177 for (i = 0; i <= FL_HASH_MASK; i++) { 178 struct ip6_flowlabel *fl; 179 struct ip6_flowlabel __rcu **flp; 180 181 flp = &fl_ht[i]; 182 while ((fl = rcu_dereference_protected(*flp, 183 lockdep_is_held(&ip6_fl_lock))) != NULL) { 184 if (net_eq(fl->fl_net, net) && 185 atomic_read(&fl->users) == 0) { 186 *flp = fl->next; 187 fl_free(fl); 188 atomic_dec(&fl_size); 189 continue; 190 } 191 flp = &fl->next; 192 } 193 } 194 spin_unlock_bh(&ip6_fl_lock); 195 } 196 197 static struct ip6_flowlabel *fl_intern(struct net *net, 198 struct ip6_flowlabel *fl, __be32 label) 199 { 200 struct ip6_flowlabel *lfl; 201 202 fl->label = label & IPV6_FLOWLABEL_MASK; 203 204 spin_lock_bh(&ip6_fl_lock); 205 if (label == 0) { 206 for (;;) { 207 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK; 208 if (fl->label) { 209 lfl = __fl_lookup(net, fl->label); 210 if (!lfl) 211 break; 212 } 213 } 214 } else { 215 /* 216 * we dropper the ip6_fl_lock, so this entry could reappear 217 * and we need to recheck with it. 218 * 219 * OTOH no need to search the active socket first, like it is 220 * done in ipv6_flowlabel_opt - sock is locked, so new entry 221 * with the same label can only appear on another sock 222 */ 223 lfl = __fl_lookup(net, fl->label); 224 if (lfl) { 225 atomic_inc(&lfl->users); 226 spin_unlock_bh(&ip6_fl_lock); 227 return lfl; 228 } 229 } 230 231 fl->lastuse = jiffies; 232 fl->next = fl_ht[FL_HASH(fl->label)]; 233 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 234 atomic_inc(&fl_size); 235 spin_unlock_bh(&ip6_fl_lock); 236 return NULL; 237 } 238 239 240 241 /* Socket flowlabel lists */ 242 243 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label) 244 { 245 struct ipv6_fl_socklist *sfl; 246 struct ipv6_pinfo *np = inet6_sk(sk); 247 248 label &= IPV6_FLOWLABEL_MASK; 249 250 rcu_read_lock_bh(); 251 for_each_sk_fl_rcu(np, sfl) { 252 struct ip6_flowlabel *fl = sfl->fl; 253 if (fl->label == label) { 254 fl->lastuse = jiffies; 255 atomic_inc(&fl->users); 256 rcu_read_unlock_bh(); 257 return fl; 258 } 259 } 260 rcu_read_unlock_bh(); 261 return NULL; 262 } 263 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 264 265 void fl6_free_socklist(struct sock *sk) 266 { 267 struct ipv6_pinfo *np = inet6_sk(sk); 268 struct ipv6_fl_socklist *sfl; 269 270 if (!rcu_access_pointer(np->ipv6_fl_list)) 271 return; 272 273 spin_lock_bh(&ip6_sk_fl_lock); 274 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 275 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 276 np->ipv6_fl_list = sfl->next; 277 spin_unlock_bh(&ip6_sk_fl_lock); 278 279 fl_release(sfl->fl); 280 kfree_rcu(sfl, rcu); 281 282 spin_lock_bh(&ip6_sk_fl_lock); 283 } 284 spin_unlock_bh(&ip6_sk_fl_lock); 285 } 286 287 /* Service routines */ 288 289 290 /* 291 It is the only difficult place. flowlabel enforces equal headers 292 before and including routing header, however user may supply options 293 following rthdr. 294 */ 295 296 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 297 struct ip6_flowlabel *fl, 298 struct ipv6_txoptions *fopt) 299 { 300 struct ipv6_txoptions *fl_opt = fl->opt; 301 302 if (!fopt || fopt->opt_flen == 0) 303 return fl_opt; 304 305 if (fl_opt) { 306 opt_space->hopopt = fl_opt->hopopt; 307 opt_space->dst0opt = fl_opt->dst0opt; 308 opt_space->srcrt = fl_opt->srcrt; 309 opt_space->opt_nflen = fl_opt->opt_nflen; 310 } else { 311 if (fopt->opt_nflen == 0) 312 return fopt; 313 opt_space->hopopt = NULL; 314 opt_space->dst0opt = NULL; 315 opt_space->srcrt = NULL; 316 opt_space->opt_nflen = 0; 317 } 318 opt_space->dst1opt = fopt->dst1opt; 319 opt_space->opt_flen = fopt->opt_flen; 320 opt_space->tot_len = fopt->tot_len; 321 return opt_space; 322 } 323 EXPORT_SYMBOL_GPL(fl6_merge_options); 324 325 static unsigned long check_linger(unsigned long ttl) 326 { 327 if (ttl < FL_MIN_LINGER) 328 return FL_MIN_LINGER*HZ; 329 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 330 return 0; 331 return ttl*HZ; 332 } 333 334 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 335 { 336 linger = check_linger(linger); 337 if (!linger) 338 return -EPERM; 339 expires = check_linger(expires); 340 if (!expires) 341 return -EPERM; 342 343 spin_lock_bh(&ip6_fl_lock); 344 fl->lastuse = jiffies; 345 if (time_before(fl->linger, linger)) 346 fl->linger = linger; 347 if (time_before(expires, fl->linger)) 348 expires = fl->linger; 349 if (time_before(fl->expires, fl->lastuse + expires)) 350 fl->expires = fl->lastuse + expires; 351 spin_unlock_bh(&ip6_fl_lock); 352 353 return 0; 354 } 355 356 static struct ip6_flowlabel * 357 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 358 char __user *optval, int optlen, int *err_p) 359 { 360 struct ip6_flowlabel *fl = NULL; 361 int olen; 362 int addr_type; 363 int err; 364 365 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 366 err = -EINVAL; 367 if (olen > 64 * 1024) 368 goto done; 369 370 err = -ENOMEM; 371 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 372 if (!fl) 373 goto done; 374 375 if (olen > 0) { 376 struct msghdr msg; 377 struct flowi6 flowi6; 378 struct ipcm6_cookie ipc6; 379 380 err = -ENOMEM; 381 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 382 if (!fl->opt) 383 goto done; 384 385 memset(fl->opt, 0, sizeof(*fl->opt)); 386 fl->opt->tot_len = sizeof(*fl->opt) + olen; 387 err = -EFAULT; 388 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen)) 389 goto done; 390 391 msg.msg_controllen = olen; 392 msg.msg_control = (void *)(fl->opt+1); 393 memset(&flowi6, 0, sizeof(flowi6)); 394 395 ipc6.opt = fl->opt; 396 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6); 397 if (err) 398 goto done; 399 err = -EINVAL; 400 if (fl->opt->opt_flen) 401 goto done; 402 if (fl->opt->opt_nflen == 0) { 403 kfree(fl->opt); 404 fl->opt = NULL; 405 } 406 } 407 408 fl->fl_net = net; 409 fl->expires = jiffies; 410 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 411 if (err) 412 goto done; 413 fl->share = freq->flr_share; 414 addr_type = ipv6_addr_type(&freq->flr_dst); 415 if ((addr_type & IPV6_ADDR_MAPPED) || 416 addr_type == IPV6_ADDR_ANY) { 417 err = -EINVAL; 418 goto done; 419 } 420 fl->dst = freq->flr_dst; 421 atomic_set(&fl->users, 1); 422 switch (fl->share) { 423 case IPV6_FL_S_EXCL: 424 case IPV6_FL_S_ANY: 425 break; 426 case IPV6_FL_S_PROCESS: 427 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 428 break; 429 case IPV6_FL_S_USER: 430 fl->owner.uid = current_euid(); 431 break; 432 default: 433 err = -EINVAL; 434 goto done; 435 } 436 return fl; 437 438 done: 439 fl_free(fl); 440 *err_p = err; 441 return NULL; 442 } 443 444 static int mem_check(struct sock *sk) 445 { 446 struct ipv6_pinfo *np = inet6_sk(sk); 447 struct ipv6_fl_socklist *sfl; 448 int room = FL_MAX_SIZE - atomic_read(&fl_size); 449 int count = 0; 450 451 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 452 return 0; 453 454 rcu_read_lock_bh(); 455 for_each_sk_fl_rcu(np, sfl) 456 count++; 457 rcu_read_unlock_bh(); 458 459 if (room <= 0 || 460 ((count >= FL_MAX_PER_SOCK || 461 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 462 !capable(CAP_NET_ADMIN))) 463 return -ENOBUFS; 464 465 return 0; 466 } 467 468 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 469 struct ip6_flowlabel *fl) 470 { 471 spin_lock_bh(&ip6_sk_fl_lock); 472 sfl->fl = fl; 473 sfl->next = np->ipv6_fl_list; 474 rcu_assign_pointer(np->ipv6_fl_list, sfl); 475 spin_unlock_bh(&ip6_sk_fl_lock); 476 } 477 478 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 479 int flags) 480 { 481 struct ipv6_pinfo *np = inet6_sk(sk); 482 struct ipv6_fl_socklist *sfl; 483 484 if (flags & IPV6_FL_F_REMOTE) { 485 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 486 return 0; 487 } 488 489 if (np->repflow) { 490 freq->flr_label = np->flow_label; 491 return 0; 492 } 493 494 rcu_read_lock_bh(); 495 496 for_each_sk_fl_rcu(np, sfl) { 497 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 498 spin_lock_bh(&ip6_fl_lock); 499 freq->flr_label = sfl->fl->label; 500 freq->flr_dst = sfl->fl->dst; 501 freq->flr_share = sfl->fl->share; 502 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 503 freq->flr_linger = sfl->fl->linger / HZ; 504 505 spin_unlock_bh(&ip6_fl_lock); 506 rcu_read_unlock_bh(); 507 return 0; 508 } 509 } 510 rcu_read_unlock_bh(); 511 512 return -ENOENT; 513 } 514 515 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen) 516 { 517 int uninitialized_var(err); 518 struct net *net = sock_net(sk); 519 struct ipv6_pinfo *np = inet6_sk(sk); 520 struct in6_flowlabel_req freq; 521 struct ipv6_fl_socklist *sfl1 = NULL; 522 struct ipv6_fl_socklist *sfl; 523 struct ipv6_fl_socklist __rcu **sflp; 524 struct ip6_flowlabel *fl, *fl1 = NULL; 525 526 527 if (optlen < sizeof(freq)) 528 return -EINVAL; 529 530 if (copy_from_user(&freq, optval, sizeof(freq))) 531 return -EFAULT; 532 533 switch (freq.flr_action) { 534 case IPV6_FL_A_PUT: 535 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 536 if (sk->sk_protocol != IPPROTO_TCP) 537 return -ENOPROTOOPT; 538 if (!np->repflow) 539 return -ESRCH; 540 np->flow_label = 0; 541 np->repflow = 0; 542 return 0; 543 } 544 spin_lock_bh(&ip6_sk_fl_lock); 545 for (sflp = &np->ipv6_fl_list; 546 (sfl = rcu_dereference_protected(*sflp, 547 lockdep_is_held(&ip6_sk_fl_lock))) != NULL; 548 sflp = &sfl->next) { 549 if (sfl->fl->label == freq.flr_label) { 550 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK)) 551 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 552 *sflp = sfl->next; 553 spin_unlock_bh(&ip6_sk_fl_lock); 554 fl_release(sfl->fl); 555 kfree_rcu(sfl, rcu); 556 return 0; 557 } 558 } 559 spin_unlock_bh(&ip6_sk_fl_lock); 560 return -ESRCH; 561 562 case IPV6_FL_A_RENEW: 563 rcu_read_lock_bh(); 564 for_each_sk_fl_rcu(np, sfl) { 565 if (sfl->fl->label == freq.flr_label) { 566 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires); 567 rcu_read_unlock_bh(); 568 return err; 569 } 570 } 571 rcu_read_unlock_bh(); 572 573 if (freq.flr_share == IPV6_FL_S_NONE && 574 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 575 fl = fl_lookup(net, freq.flr_label); 576 if (fl) { 577 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires); 578 fl_release(fl); 579 return err; 580 } 581 } 582 return -ESRCH; 583 584 case IPV6_FL_A_GET: 585 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 586 struct net *net = sock_net(sk); 587 if (net->ipv6.sysctl.flowlabel_consistency) { 588 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 589 return -EPERM; 590 } 591 592 if (sk->sk_protocol != IPPROTO_TCP) 593 return -ENOPROTOOPT; 594 595 np->repflow = 1; 596 return 0; 597 } 598 599 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK) 600 return -EINVAL; 601 602 if (net->ipv6.sysctl.flowlabel_state_ranges && 603 (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 604 return -ERANGE; 605 606 fl = fl_create(net, sk, &freq, optval, optlen, &err); 607 if (!fl) 608 return err; 609 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 610 611 if (freq.flr_label) { 612 err = -EEXIST; 613 rcu_read_lock_bh(); 614 for_each_sk_fl_rcu(np, sfl) { 615 if (sfl->fl->label == freq.flr_label) { 616 if (freq.flr_flags&IPV6_FL_F_EXCL) { 617 rcu_read_unlock_bh(); 618 goto done; 619 } 620 fl1 = sfl->fl; 621 atomic_inc(&fl1->users); 622 break; 623 } 624 } 625 rcu_read_unlock_bh(); 626 627 if (!fl1) 628 fl1 = fl_lookup(net, freq.flr_label); 629 if (fl1) { 630 recheck: 631 err = -EEXIST; 632 if (freq.flr_flags&IPV6_FL_F_EXCL) 633 goto release; 634 err = -EPERM; 635 if (fl1->share == IPV6_FL_S_EXCL || 636 fl1->share != fl->share || 637 ((fl1->share == IPV6_FL_S_PROCESS) && 638 (fl1->owner.pid != fl->owner.pid)) || 639 ((fl1->share == IPV6_FL_S_USER) && 640 !uid_eq(fl1->owner.uid, fl->owner.uid))) 641 goto release; 642 643 err = -ENOMEM; 644 if (!sfl1) 645 goto release; 646 if (fl->linger > fl1->linger) 647 fl1->linger = fl->linger; 648 if ((long)(fl->expires - fl1->expires) > 0) 649 fl1->expires = fl->expires; 650 fl_link(np, sfl1, fl1); 651 fl_free(fl); 652 return 0; 653 654 release: 655 fl_release(fl1); 656 goto done; 657 } 658 } 659 err = -ENOENT; 660 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 661 goto done; 662 663 err = -ENOMEM; 664 if (!sfl1) 665 goto done; 666 667 err = mem_check(sk); 668 if (err != 0) 669 goto done; 670 671 fl1 = fl_intern(net, fl, freq.flr_label); 672 if (fl1) 673 goto recheck; 674 675 if (!freq.flr_label) { 676 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 677 &fl->label, sizeof(fl->label))) { 678 /* Intentionally ignore fault. */ 679 } 680 } 681 682 fl_link(np, sfl1, fl); 683 return 0; 684 685 default: 686 return -EINVAL; 687 } 688 689 done: 690 fl_free(fl); 691 kfree(sfl1); 692 return err; 693 } 694 695 #ifdef CONFIG_PROC_FS 696 697 struct ip6fl_iter_state { 698 struct seq_net_private p; 699 struct pid_namespace *pid_ns; 700 int bucket; 701 }; 702 703 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 704 705 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 706 { 707 struct ip6_flowlabel *fl = NULL; 708 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 709 struct net *net = seq_file_net(seq); 710 711 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 712 for_each_fl_rcu(state->bucket, fl) { 713 if (net_eq(fl->fl_net, net)) 714 goto out; 715 } 716 } 717 fl = NULL; 718 out: 719 return fl; 720 } 721 722 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 723 { 724 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 725 struct net *net = seq_file_net(seq); 726 727 for_each_fl_continue_rcu(fl) { 728 if (net_eq(fl->fl_net, net)) 729 goto out; 730 } 731 732 try_again: 733 if (++state->bucket <= FL_HASH_MASK) { 734 for_each_fl_rcu(state->bucket, fl) { 735 if (net_eq(fl->fl_net, net)) 736 goto out; 737 } 738 goto try_again; 739 } 740 fl = NULL; 741 742 out: 743 return fl; 744 } 745 746 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 747 { 748 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 749 if (fl) 750 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 751 --pos; 752 return pos ? NULL : fl; 753 } 754 755 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 756 __acquires(RCU) 757 { 758 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 759 760 state->pid_ns = proc_pid_ns(file_inode(seq->file)); 761 762 rcu_read_lock_bh(); 763 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 764 } 765 766 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 767 { 768 struct ip6_flowlabel *fl; 769 770 if (v == SEQ_START_TOKEN) 771 fl = ip6fl_get_first(seq); 772 else 773 fl = ip6fl_get_next(seq, v); 774 ++*pos; 775 return fl; 776 } 777 778 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 779 __releases(RCU) 780 { 781 rcu_read_unlock_bh(); 782 } 783 784 static int ip6fl_seq_show(struct seq_file *seq, void *v) 785 { 786 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 787 if (v == SEQ_START_TOKEN) { 788 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 789 } else { 790 struct ip6_flowlabel *fl = v; 791 seq_printf(seq, 792 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 793 (unsigned int)ntohl(fl->label), 794 fl->share, 795 ((fl->share == IPV6_FL_S_PROCESS) ? 796 pid_nr_ns(fl->owner.pid, state->pid_ns) : 797 ((fl->share == IPV6_FL_S_USER) ? 798 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 799 0)), 800 atomic_read(&fl->users), 801 fl->linger/HZ, 802 (long)(fl->expires - jiffies)/HZ, 803 &fl->dst, 804 fl->opt ? fl->opt->opt_nflen : 0); 805 } 806 return 0; 807 } 808 809 static const struct seq_operations ip6fl_seq_ops = { 810 .start = ip6fl_seq_start, 811 .next = ip6fl_seq_next, 812 .stop = ip6fl_seq_stop, 813 .show = ip6fl_seq_show, 814 }; 815 816 static int __net_init ip6_flowlabel_proc_init(struct net *net) 817 { 818 if (!proc_create_net("ip6_flowlabel", 0444, net->proc_net, 819 &ip6fl_seq_ops, sizeof(struct ip6fl_iter_state))) 820 return -ENOMEM; 821 return 0; 822 } 823 824 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 825 { 826 remove_proc_entry("ip6_flowlabel", net->proc_net); 827 } 828 #else 829 static inline int ip6_flowlabel_proc_init(struct net *net) 830 { 831 return 0; 832 } 833 static inline void ip6_flowlabel_proc_fini(struct net *net) 834 { 835 } 836 #endif 837 838 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 839 { 840 ip6_fl_purge(net); 841 ip6_flowlabel_proc_fini(net); 842 } 843 844 static struct pernet_operations ip6_flowlabel_net_ops = { 845 .init = ip6_flowlabel_proc_init, 846 .exit = ip6_flowlabel_net_exit, 847 }; 848 849 int ip6_flowlabel_init(void) 850 { 851 return register_pernet_subsys(&ip6_flowlabel_net_ops); 852 } 853 854 void ip6_flowlabel_cleanup(void) 855 { 856 del_timer(&ip6_fl_gc_timer); 857 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 858 } 859