1 /* 2 * ip6_flowlabel.c IPv6 flowlabel manager. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10 */ 11 12 #include <linux/capability.h> 13 #include <linux/errno.h> 14 #include <linux/types.h> 15 #include <linux/socket.h> 16 #include <linux/net.h> 17 #include <linux/netdevice.h> 18 #include <linux/in6.h> 19 #include <linux/proc_fs.h> 20 #include <linux/seq_file.h> 21 #include <linux/slab.h> 22 #include <linux/export.h> 23 #include <linux/pid_namespace.h> 24 25 #include <net/net_namespace.h> 26 #include <net/sock.h> 27 28 #include <net/ipv6.h> 29 #include <net/rawv6.h> 30 #include <net/transp_v6.h> 31 32 #include <asm/uaccess.h> 33 34 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified 35 in old IPv6 RFC. Well, it was reasonable value. 36 */ 37 #define FL_MAX_LINGER 150 /* Maximal linger timeout */ 38 39 /* FL hash table */ 40 41 #define FL_MAX_PER_SOCK 32 42 #define FL_MAX_SIZE 4096 43 #define FL_HASH_MASK 255 44 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK) 45 46 static atomic_t fl_size = ATOMIC_INIT(0); 47 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1]; 48 49 static void ip6_fl_gc(unsigned long dummy); 50 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0); 51 52 /* FL hash table lock: it protects only of GC */ 53 54 static DEFINE_SPINLOCK(ip6_fl_lock); 55 56 /* Big socket sock */ 57 58 static DEFINE_SPINLOCK(ip6_sk_fl_lock); 59 60 #define for_each_fl_rcu(hash, fl) \ 61 for (fl = rcu_dereference_bh(fl_ht[(hash)]); \ 62 fl != NULL; \ 63 fl = rcu_dereference_bh(fl->next)) 64 #define for_each_fl_continue_rcu(fl) \ 65 for (fl = rcu_dereference_bh(fl->next); \ 66 fl != NULL; \ 67 fl = rcu_dereference_bh(fl->next)) 68 69 #define for_each_sk_fl_rcu(np, sfl) \ 70 for (sfl = rcu_dereference_bh(np->ipv6_fl_list); \ 71 sfl != NULL; \ 72 sfl = rcu_dereference_bh(sfl->next)) 73 74 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label) 75 { 76 struct ip6_flowlabel *fl; 77 78 for_each_fl_rcu(FL_HASH(label), fl) { 79 if (fl->label == label && net_eq(fl->fl_net, net)) 80 return fl; 81 } 82 return NULL; 83 } 84 85 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) 86 { 87 struct ip6_flowlabel *fl; 88 89 rcu_read_lock_bh(); 90 fl = __fl_lookup(net, label); 91 if (fl && !atomic_inc_not_zero(&fl->users)) 92 fl = NULL; 93 rcu_read_unlock_bh(); 94 return fl; 95 } 96 97 98 static void fl_free(struct ip6_flowlabel *fl) 99 { 100 if (fl) { 101 if (fl->share == IPV6_FL_S_PROCESS) 102 put_pid(fl->owner.pid); 103 kfree(fl->opt); 104 kfree_rcu(fl, rcu); 105 } 106 } 107 108 static void fl_release(struct ip6_flowlabel *fl) 109 { 110 spin_lock_bh(&ip6_fl_lock); 111 112 fl->lastuse = jiffies; 113 if (atomic_dec_and_test(&fl->users)) { 114 unsigned long ttd = fl->lastuse + fl->linger; 115 if (time_after(ttd, fl->expires)) 116 fl->expires = ttd; 117 ttd = fl->expires; 118 if (fl->opt && fl->share == IPV6_FL_S_EXCL) { 119 struct ipv6_txoptions *opt = fl->opt; 120 fl->opt = NULL; 121 kfree(opt); 122 } 123 if (!timer_pending(&ip6_fl_gc_timer) || 124 time_after(ip6_fl_gc_timer.expires, ttd)) 125 mod_timer(&ip6_fl_gc_timer, ttd); 126 } 127 spin_unlock_bh(&ip6_fl_lock); 128 } 129 130 static void ip6_fl_gc(unsigned long dummy) 131 { 132 int i; 133 unsigned long now = jiffies; 134 unsigned long sched = 0; 135 136 spin_lock(&ip6_fl_lock); 137 138 for (i = 0; i <= FL_HASH_MASK; i++) { 139 struct ip6_flowlabel *fl; 140 struct ip6_flowlabel __rcu **flp; 141 142 flp = &fl_ht[i]; 143 while ((fl = rcu_dereference_protected(*flp, 144 lockdep_is_held(&ip6_fl_lock))) != NULL) { 145 if (atomic_read(&fl->users) == 0) { 146 unsigned long ttd = fl->lastuse + fl->linger; 147 if (time_after(ttd, fl->expires)) 148 fl->expires = ttd; 149 ttd = fl->expires; 150 if (time_after_eq(now, ttd)) { 151 *flp = fl->next; 152 fl_free(fl); 153 atomic_dec(&fl_size); 154 continue; 155 } 156 if (!sched || time_before(ttd, sched)) 157 sched = ttd; 158 } 159 flp = &fl->next; 160 } 161 } 162 if (!sched && atomic_read(&fl_size)) 163 sched = now + FL_MAX_LINGER; 164 if (sched) { 165 mod_timer(&ip6_fl_gc_timer, sched); 166 } 167 spin_unlock(&ip6_fl_lock); 168 } 169 170 static void __net_exit ip6_fl_purge(struct net *net) 171 { 172 int i; 173 174 spin_lock_bh(&ip6_fl_lock); 175 for (i = 0; i <= FL_HASH_MASK; i++) { 176 struct ip6_flowlabel *fl; 177 struct ip6_flowlabel __rcu **flp; 178 179 flp = &fl_ht[i]; 180 while ((fl = rcu_dereference_protected(*flp, 181 lockdep_is_held(&ip6_fl_lock))) != NULL) { 182 if (net_eq(fl->fl_net, net) && 183 atomic_read(&fl->users) == 0) { 184 *flp = fl->next; 185 fl_free(fl); 186 atomic_dec(&fl_size); 187 continue; 188 } 189 flp = &fl->next; 190 } 191 } 192 spin_unlock_bh(&ip6_fl_lock); 193 } 194 195 static struct ip6_flowlabel *fl_intern(struct net *net, 196 struct ip6_flowlabel *fl, __be32 label) 197 { 198 struct ip6_flowlabel *lfl; 199 200 fl->label = label & IPV6_FLOWLABEL_MASK; 201 202 spin_lock_bh(&ip6_fl_lock); 203 if (label == 0) { 204 for (;;) { 205 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK; 206 if (fl->label) { 207 lfl = __fl_lookup(net, fl->label); 208 if (!lfl) 209 break; 210 } 211 } 212 } else { 213 /* 214 * we dropper the ip6_fl_lock, so this entry could reappear 215 * and we need to recheck with it. 216 * 217 * OTOH no need to search the active socket first, like it is 218 * done in ipv6_flowlabel_opt - sock is locked, so new entry 219 * with the same label can only appear on another sock 220 */ 221 lfl = __fl_lookup(net, fl->label); 222 if (lfl) { 223 atomic_inc(&lfl->users); 224 spin_unlock_bh(&ip6_fl_lock); 225 return lfl; 226 } 227 } 228 229 fl->lastuse = jiffies; 230 fl->next = fl_ht[FL_HASH(fl->label)]; 231 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 232 atomic_inc(&fl_size); 233 spin_unlock_bh(&ip6_fl_lock); 234 return NULL; 235 } 236 237 238 239 /* Socket flowlabel lists */ 240 241 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label) 242 { 243 struct ipv6_fl_socklist *sfl; 244 struct ipv6_pinfo *np = inet6_sk(sk); 245 246 label &= IPV6_FLOWLABEL_MASK; 247 248 rcu_read_lock_bh(); 249 for_each_sk_fl_rcu(np, sfl) { 250 struct ip6_flowlabel *fl = sfl->fl; 251 if (fl->label == label) { 252 fl->lastuse = jiffies; 253 atomic_inc(&fl->users); 254 rcu_read_unlock_bh(); 255 return fl; 256 } 257 } 258 rcu_read_unlock_bh(); 259 return NULL; 260 } 261 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 262 263 void fl6_free_socklist(struct sock *sk) 264 { 265 struct ipv6_pinfo *np = inet6_sk(sk); 266 struct ipv6_fl_socklist *sfl; 267 268 if (!rcu_access_pointer(np->ipv6_fl_list)) 269 return; 270 271 spin_lock_bh(&ip6_sk_fl_lock); 272 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 273 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 274 np->ipv6_fl_list = sfl->next; 275 spin_unlock_bh(&ip6_sk_fl_lock); 276 277 fl_release(sfl->fl); 278 kfree_rcu(sfl, rcu); 279 280 spin_lock_bh(&ip6_sk_fl_lock); 281 } 282 spin_unlock_bh(&ip6_sk_fl_lock); 283 } 284 285 /* Service routines */ 286 287 288 /* 289 It is the only difficult place. flowlabel enforces equal headers 290 before and including routing header, however user may supply options 291 following rthdr. 292 */ 293 294 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 295 struct ip6_flowlabel *fl, 296 struct ipv6_txoptions *fopt) 297 { 298 struct ipv6_txoptions *fl_opt = fl->opt; 299 300 if (!fopt || fopt->opt_flen == 0) 301 return fl_opt; 302 303 if (fl_opt) { 304 opt_space->hopopt = fl_opt->hopopt; 305 opt_space->dst0opt = fl_opt->dst0opt; 306 opt_space->srcrt = fl_opt->srcrt; 307 opt_space->opt_nflen = fl_opt->opt_nflen; 308 } else { 309 if (fopt->opt_nflen == 0) 310 return fopt; 311 opt_space->hopopt = NULL; 312 opt_space->dst0opt = NULL; 313 opt_space->srcrt = NULL; 314 opt_space->opt_nflen = 0; 315 } 316 opt_space->dst1opt = fopt->dst1opt; 317 opt_space->opt_flen = fopt->opt_flen; 318 return opt_space; 319 } 320 EXPORT_SYMBOL_GPL(fl6_merge_options); 321 322 static unsigned long check_linger(unsigned long ttl) 323 { 324 if (ttl < FL_MIN_LINGER) 325 return FL_MIN_LINGER*HZ; 326 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 327 return 0; 328 return ttl*HZ; 329 } 330 331 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 332 { 333 linger = check_linger(linger); 334 if (!linger) 335 return -EPERM; 336 expires = check_linger(expires); 337 if (!expires) 338 return -EPERM; 339 340 spin_lock_bh(&ip6_fl_lock); 341 fl->lastuse = jiffies; 342 if (time_before(fl->linger, linger)) 343 fl->linger = linger; 344 if (time_before(expires, fl->linger)) 345 expires = fl->linger; 346 if (time_before(fl->expires, fl->lastuse + expires)) 347 fl->expires = fl->lastuse + expires; 348 spin_unlock_bh(&ip6_fl_lock); 349 350 return 0; 351 } 352 353 static struct ip6_flowlabel * 354 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 355 char __user *optval, int optlen, int *err_p) 356 { 357 struct ip6_flowlabel *fl = NULL; 358 int olen; 359 int addr_type; 360 int err; 361 362 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 363 err = -EINVAL; 364 if (olen > 64 * 1024) 365 goto done; 366 367 err = -ENOMEM; 368 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 369 if (!fl) 370 goto done; 371 372 if (olen > 0) { 373 struct msghdr msg; 374 struct flowi6 flowi6; 375 int junk; 376 377 err = -ENOMEM; 378 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 379 if (!fl->opt) 380 goto done; 381 382 memset(fl->opt, 0, sizeof(*fl->opt)); 383 fl->opt->tot_len = sizeof(*fl->opt) + olen; 384 err = -EFAULT; 385 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen)) 386 goto done; 387 388 msg.msg_controllen = olen; 389 msg.msg_control = (void *)(fl->opt+1); 390 memset(&flowi6, 0, sizeof(flowi6)); 391 392 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, fl->opt, 393 &junk, &junk, &junk); 394 if (err) 395 goto done; 396 err = -EINVAL; 397 if (fl->opt->opt_flen) 398 goto done; 399 if (fl->opt->opt_nflen == 0) { 400 kfree(fl->opt); 401 fl->opt = NULL; 402 } 403 } 404 405 fl->fl_net = net; 406 fl->expires = jiffies; 407 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 408 if (err) 409 goto done; 410 fl->share = freq->flr_share; 411 addr_type = ipv6_addr_type(&freq->flr_dst); 412 if ((addr_type & IPV6_ADDR_MAPPED) || 413 addr_type == IPV6_ADDR_ANY) { 414 err = -EINVAL; 415 goto done; 416 } 417 fl->dst = freq->flr_dst; 418 atomic_set(&fl->users, 1); 419 switch (fl->share) { 420 case IPV6_FL_S_EXCL: 421 case IPV6_FL_S_ANY: 422 break; 423 case IPV6_FL_S_PROCESS: 424 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 425 break; 426 case IPV6_FL_S_USER: 427 fl->owner.uid = current_euid(); 428 break; 429 default: 430 err = -EINVAL; 431 goto done; 432 } 433 return fl; 434 435 done: 436 fl_free(fl); 437 *err_p = err; 438 return NULL; 439 } 440 441 static int mem_check(struct sock *sk) 442 { 443 struct ipv6_pinfo *np = inet6_sk(sk); 444 struct ipv6_fl_socklist *sfl; 445 int room = FL_MAX_SIZE - atomic_read(&fl_size); 446 int count = 0; 447 448 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 449 return 0; 450 451 rcu_read_lock_bh(); 452 for_each_sk_fl_rcu(np, sfl) 453 count++; 454 rcu_read_unlock_bh(); 455 456 if (room <= 0 || 457 ((count >= FL_MAX_PER_SOCK || 458 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 459 !capable(CAP_NET_ADMIN))) 460 return -ENOBUFS; 461 462 return 0; 463 } 464 465 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 466 struct ip6_flowlabel *fl) 467 { 468 spin_lock_bh(&ip6_sk_fl_lock); 469 sfl->fl = fl; 470 sfl->next = np->ipv6_fl_list; 471 rcu_assign_pointer(np->ipv6_fl_list, sfl); 472 spin_unlock_bh(&ip6_sk_fl_lock); 473 } 474 475 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 476 int flags) 477 { 478 struct ipv6_pinfo *np = inet6_sk(sk); 479 struct ipv6_fl_socklist *sfl; 480 481 if (flags & IPV6_FL_F_REMOTE) { 482 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 483 return 0; 484 } 485 486 if (np->repflow) { 487 freq->flr_label = np->flow_label; 488 return 0; 489 } 490 491 rcu_read_lock_bh(); 492 493 for_each_sk_fl_rcu(np, sfl) { 494 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 495 spin_lock_bh(&ip6_fl_lock); 496 freq->flr_label = sfl->fl->label; 497 freq->flr_dst = sfl->fl->dst; 498 freq->flr_share = sfl->fl->share; 499 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 500 freq->flr_linger = sfl->fl->linger / HZ; 501 502 spin_unlock_bh(&ip6_fl_lock); 503 rcu_read_unlock_bh(); 504 return 0; 505 } 506 } 507 rcu_read_unlock_bh(); 508 509 return -ENOENT; 510 } 511 512 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen) 513 { 514 int uninitialized_var(err); 515 struct net *net = sock_net(sk); 516 struct ipv6_pinfo *np = inet6_sk(sk); 517 struct in6_flowlabel_req freq; 518 struct ipv6_fl_socklist *sfl1 = NULL; 519 struct ipv6_fl_socklist *sfl; 520 struct ipv6_fl_socklist __rcu **sflp; 521 struct ip6_flowlabel *fl, *fl1 = NULL; 522 523 524 if (optlen < sizeof(freq)) 525 return -EINVAL; 526 527 if (copy_from_user(&freq, optval, sizeof(freq))) 528 return -EFAULT; 529 530 switch (freq.flr_action) { 531 case IPV6_FL_A_PUT: 532 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 533 if (sk->sk_protocol != IPPROTO_TCP) 534 return -ENOPROTOOPT; 535 if (!np->repflow) 536 return -ESRCH; 537 np->flow_label = 0; 538 np->repflow = 0; 539 return 0; 540 } 541 spin_lock_bh(&ip6_sk_fl_lock); 542 for (sflp = &np->ipv6_fl_list; 543 (sfl = rcu_dereference(*sflp)) != NULL; 544 sflp = &sfl->next) { 545 if (sfl->fl->label == freq.flr_label) { 546 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK)) 547 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 548 *sflp = rcu_dereference(sfl->next); 549 spin_unlock_bh(&ip6_sk_fl_lock); 550 fl_release(sfl->fl); 551 kfree_rcu(sfl, rcu); 552 return 0; 553 } 554 } 555 spin_unlock_bh(&ip6_sk_fl_lock); 556 return -ESRCH; 557 558 case IPV6_FL_A_RENEW: 559 rcu_read_lock_bh(); 560 for_each_sk_fl_rcu(np, sfl) { 561 if (sfl->fl->label == freq.flr_label) { 562 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires); 563 rcu_read_unlock_bh(); 564 return err; 565 } 566 } 567 rcu_read_unlock_bh(); 568 569 if (freq.flr_share == IPV6_FL_S_NONE && 570 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 571 fl = fl_lookup(net, freq.flr_label); 572 if (fl) { 573 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires); 574 fl_release(fl); 575 return err; 576 } 577 } 578 return -ESRCH; 579 580 case IPV6_FL_A_GET: 581 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 582 struct net *net = sock_net(sk); 583 if (net->ipv6.sysctl.flowlabel_consistency) { 584 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 585 return -EPERM; 586 } 587 588 if (sk->sk_protocol != IPPROTO_TCP) 589 return -ENOPROTOOPT; 590 591 np->repflow = 1; 592 return 0; 593 } 594 595 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK) 596 return -EINVAL; 597 598 if (net->ipv6.sysctl.flowlabel_state_ranges && 599 (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 600 return -ERANGE; 601 602 fl = fl_create(net, sk, &freq, optval, optlen, &err); 603 if (!fl) 604 return err; 605 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 606 607 if (freq.flr_label) { 608 err = -EEXIST; 609 rcu_read_lock_bh(); 610 for_each_sk_fl_rcu(np, sfl) { 611 if (sfl->fl->label == freq.flr_label) { 612 if (freq.flr_flags&IPV6_FL_F_EXCL) { 613 rcu_read_unlock_bh(); 614 goto done; 615 } 616 fl1 = sfl->fl; 617 atomic_inc(&fl1->users); 618 break; 619 } 620 } 621 rcu_read_unlock_bh(); 622 623 if (!fl1) 624 fl1 = fl_lookup(net, freq.flr_label); 625 if (fl1) { 626 recheck: 627 err = -EEXIST; 628 if (freq.flr_flags&IPV6_FL_F_EXCL) 629 goto release; 630 err = -EPERM; 631 if (fl1->share == IPV6_FL_S_EXCL || 632 fl1->share != fl->share || 633 ((fl1->share == IPV6_FL_S_PROCESS) && 634 (fl1->owner.pid == fl->owner.pid)) || 635 ((fl1->share == IPV6_FL_S_USER) && 636 uid_eq(fl1->owner.uid, fl->owner.uid))) 637 goto release; 638 639 err = -ENOMEM; 640 if (!sfl1) 641 goto release; 642 if (fl->linger > fl1->linger) 643 fl1->linger = fl->linger; 644 if ((long)(fl->expires - fl1->expires) > 0) 645 fl1->expires = fl->expires; 646 fl_link(np, sfl1, fl1); 647 fl_free(fl); 648 return 0; 649 650 release: 651 fl_release(fl1); 652 goto done; 653 } 654 } 655 err = -ENOENT; 656 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 657 goto done; 658 659 err = -ENOMEM; 660 if (!sfl1) 661 goto done; 662 663 err = mem_check(sk); 664 if (err != 0) 665 goto done; 666 667 fl1 = fl_intern(net, fl, freq.flr_label); 668 if (fl1) 669 goto recheck; 670 671 if (!freq.flr_label) { 672 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 673 &fl->label, sizeof(fl->label))) { 674 /* Intentionally ignore fault. */ 675 } 676 } 677 678 fl_link(np, sfl1, fl); 679 return 0; 680 681 default: 682 return -EINVAL; 683 } 684 685 done: 686 fl_free(fl); 687 kfree(sfl1); 688 return err; 689 } 690 691 #ifdef CONFIG_PROC_FS 692 693 struct ip6fl_iter_state { 694 struct seq_net_private p; 695 struct pid_namespace *pid_ns; 696 int bucket; 697 }; 698 699 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 700 701 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 702 { 703 struct ip6_flowlabel *fl = NULL; 704 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 705 struct net *net = seq_file_net(seq); 706 707 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 708 for_each_fl_rcu(state->bucket, fl) { 709 if (net_eq(fl->fl_net, net)) 710 goto out; 711 } 712 } 713 fl = NULL; 714 out: 715 return fl; 716 } 717 718 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 719 { 720 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 721 struct net *net = seq_file_net(seq); 722 723 for_each_fl_continue_rcu(fl) { 724 if (net_eq(fl->fl_net, net)) 725 goto out; 726 } 727 728 try_again: 729 if (++state->bucket <= FL_HASH_MASK) { 730 for_each_fl_rcu(state->bucket, fl) { 731 if (net_eq(fl->fl_net, net)) 732 goto out; 733 } 734 goto try_again; 735 } 736 fl = NULL; 737 738 out: 739 return fl; 740 } 741 742 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 743 { 744 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 745 if (fl) 746 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 747 --pos; 748 return pos ? NULL : fl; 749 } 750 751 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 752 __acquires(RCU) 753 { 754 rcu_read_lock_bh(); 755 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 756 } 757 758 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 759 { 760 struct ip6_flowlabel *fl; 761 762 if (v == SEQ_START_TOKEN) 763 fl = ip6fl_get_first(seq); 764 else 765 fl = ip6fl_get_next(seq, v); 766 ++*pos; 767 return fl; 768 } 769 770 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 771 __releases(RCU) 772 { 773 rcu_read_unlock_bh(); 774 } 775 776 static int ip6fl_seq_show(struct seq_file *seq, void *v) 777 { 778 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 779 if (v == SEQ_START_TOKEN) { 780 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 781 } else { 782 struct ip6_flowlabel *fl = v; 783 seq_printf(seq, 784 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 785 (unsigned int)ntohl(fl->label), 786 fl->share, 787 ((fl->share == IPV6_FL_S_PROCESS) ? 788 pid_nr_ns(fl->owner.pid, state->pid_ns) : 789 ((fl->share == IPV6_FL_S_USER) ? 790 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 791 0)), 792 atomic_read(&fl->users), 793 fl->linger/HZ, 794 (long)(fl->expires - jiffies)/HZ, 795 &fl->dst, 796 fl->opt ? fl->opt->opt_nflen : 0); 797 } 798 return 0; 799 } 800 801 static const struct seq_operations ip6fl_seq_ops = { 802 .start = ip6fl_seq_start, 803 .next = ip6fl_seq_next, 804 .stop = ip6fl_seq_stop, 805 .show = ip6fl_seq_show, 806 }; 807 808 static int ip6fl_seq_open(struct inode *inode, struct file *file) 809 { 810 struct seq_file *seq; 811 struct ip6fl_iter_state *state; 812 int err; 813 814 err = seq_open_net(inode, file, &ip6fl_seq_ops, 815 sizeof(struct ip6fl_iter_state)); 816 817 if (!err) { 818 seq = file->private_data; 819 state = ip6fl_seq_private(seq); 820 rcu_read_lock(); 821 state->pid_ns = get_pid_ns(task_active_pid_ns(current)); 822 rcu_read_unlock(); 823 } 824 return err; 825 } 826 827 static int ip6fl_seq_release(struct inode *inode, struct file *file) 828 { 829 struct seq_file *seq = file->private_data; 830 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 831 put_pid_ns(state->pid_ns); 832 return seq_release_net(inode, file); 833 } 834 835 static const struct file_operations ip6fl_seq_fops = { 836 .owner = THIS_MODULE, 837 .open = ip6fl_seq_open, 838 .read = seq_read, 839 .llseek = seq_lseek, 840 .release = ip6fl_seq_release, 841 }; 842 843 static int __net_init ip6_flowlabel_proc_init(struct net *net) 844 { 845 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net, 846 &ip6fl_seq_fops)) 847 return -ENOMEM; 848 return 0; 849 } 850 851 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 852 { 853 remove_proc_entry("ip6_flowlabel", net->proc_net); 854 } 855 #else 856 static inline int ip6_flowlabel_proc_init(struct net *net) 857 { 858 return 0; 859 } 860 static inline void ip6_flowlabel_proc_fini(struct net *net) 861 { 862 } 863 #endif 864 865 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 866 { 867 ip6_fl_purge(net); 868 ip6_flowlabel_proc_fini(net); 869 } 870 871 static struct pernet_operations ip6_flowlabel_net_ops = { 872 .init = ip6_flowlabel_proc_init, 873 .exit = ip6_flowlabel_net_exit, 874 }; 875 876 int ip6_flowlabel_init(void) 877 { 878 return register_pernet_subsys(&ip6_flowlabel_net_ops); 879 } 880 881 void ip6_flowlabel_cleanup(void) 882 { 883 del_timer(&ip6_fl_gc_timer); 884 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 885 } 886