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 <linux/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(struct timer_list *unused); 50 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc); 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(struct timer_list *unused) 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 opt_space->tot_len = fopt->tot_len; 319 return opt_space; 320 } 321 EXPORT_SYMBOL_GPL(fl6_merge_options); 322 323 static unsigned long check_linger(unsigned long ttl) 324 { 325 if (ttl < FL_MIN_LINGER) 326 return FL_MIN_LINGER*HZ; 327 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 328 return 0; 329 return ttl*HZ; 330 } 331 332 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 333 { 334 linger = check_linger(linger); 335 if (!linger) 336 return -EPERM; 337 expires = check_linger(expires); 338 if (!expires) 339 return -EPERM; 340 341 spin_lock_bh(&ip6_fl_lock); 342 fl->lastuse = jiffies; 343 if (time_before(fl->linger, linger)) 344 fl->linger = linger; 345 if (time_before(expires, fl->linger)) 346 expires = fl->linger; 347 if (time_before(fl->expires, fl->lastuse + expires)) 348 fl->expires = fl->lastuse + expires; 349 spin_unlock_bh(&ip6_fl_lock); 350 351 return 0; 352 } 353 354 static struct ip6_flowlabel * 355 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 356 char __user *optval, int optlen, int *err_p) 357 { 358 struct ip6_flowlabel *fl = NULL; 359 int olen; 360 int addr_type; 361 int err; 362 363 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 364 err = -EINVAL; 365 if (olen > 64 * 1024) 366 goto done; 367 368 err = -ENOMEM; 369 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 370 if (!fl) 371 goto done; 372 373 if (olen > 0) { 374 struct msghdr msg; 375 struct flowi6 flowi6; 376 struct sockcm_cookie sockc_junk; 377 struct ipcm6_cookie ipc6; 378 379 err = -ENOMEM; 380 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 381 if (!fl->opt) 382 goto done; 383 384 memset(fl->opt, 0, sizeof(*fl->opt)); 385 fl->opt->tot_len = sizeof(*fl->opt) + olen; 386 err = -EFAULT; 387 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen)) 388 goto done; 389 390 msg.msg_controllen = olen; 391 msg.msg_control = (void *)(fl->opt+1); 392 memset(&flowi6, 0, sizeof(flowi6)); 393 394 ipc6.opt = fl->opt; 395 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6, &sockc_junk); 396 if (err) 397 goto done; 398 err = -EINVAL; 399 if (fl->opt->opt_flen) 400 goto done; 401 if (fl->opt->opt_nflen == 0) { 402 kfree(fl->opt); 403 fl->opt = NULL; 404 } 405 } 406 407 fl->fl_net = net; 408 fl->expires = jiffies; 409 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 410 if (err) 411 goto done; 412 fl->share = freq->flr_share; 413 addr_type = ipv6_addr_type(&freq->flr_dst); 414 if ((addr_type & IPV6_ADDR_MAPPED) || 415 addr_type == IPV6_ADDR_ANY) { 416 err = -EINVAL; 417 goto done; 418 } 419 fl->dst = freq->flr_dst; 420 atomic_set(&fl->users, 1); 421 switch (fl->share) { 422 case IPV6_FL_S_EXCL: 423 case IPV6_FL_S_ANY: 424 break; 425 case IPV6_FL_S_PROCESS: 426 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 427 break; 428 case IPV6_FL_S_USER: 429 fl->owner.uid = current_euid(); 430 break; 431 default: 432 err = -EINVAL; 433 goto done; 434 } 435 return fl; 436 437 done: 438 fl_free(fl); 439 *err_p = err; 440 return NULL; 441 } 442 443 static int mem_check(struct sock *sk) 444 { 445 struct ipv6_pinfo *np = inet6_sk(sk); 446 struct ipv6_fl_socklist *sfl; 447 int room = FL_MAX_SIZE - atomic_read(&fl_size); 448 int count = 0; 449 450 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 451 return 0; 452 453 rcu_read_lock_bh(); 454 for_each_sk_fl_rcu(np, sfl) 455 count++; 456 rcu_read_unlock_bh(); 457 458 if (room <= 0 || 459 ((count >= FL_MAX_PER_SOCK || 460 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 461 !capable(CAP_NET_ADMIN))) 462 return -ENOBUFS; 463 464 return 0; 465 } 466 467 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 468 struct ip6_flowlabel *fl) 469 { 470 spin_lock_bh(&ip6_sk_fl_lock); 471 sfl->fl = fl; 472 sfl->next = np->ipv6_fl_list; 473 rcu_assign_pointer(np->ipv6_fl_list, sfl); 474 spin_unlock_bh(&ip6_sk_fl_lock); 475 } 476 477 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 478 int flags) 479 { 480 struct ipv6_pinfo *np = inet6_sk(sk); 481 struct ipv6_fl_socklist *sfl; 482 483 if (flags & IPV6_FL_F_REMOTE) { 484 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 485 return 0; 486 } 487 488 if (np->repflow) { 489 freq->flr_label = np->flow_label; 490 return 0; 491 } 492 493 rcu_read_lock_bh(); 494 495 for_each_sk_fl_rcu(np, sfl) { 496 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 497 spin_lock_bh(&ip6_fl_lock); 498 freq->flr_label = sfl->fl->label; 499 freq->flr_dst = sfl->fl->dst; 500 freq->flr_share = sfl->fl->share; 501 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 502 freq->flr_linger = sfl->fl->linger / HZ; 503 504 spin_unlock_bh(&ip6_fl_lock); 505 rcu_read_unlock_bh(); 506 return 0; 507 } 508 } 509 rcu_read_unlock_bh(); 510 511 return -ENOENT; 512 } 513 514 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen) 515 { 516 int uninitialized_var(err); 517 struct net *net = sock_net(sk); 518 struct ipv6_pinfo *np = inet6_sk(sk); 519 struct in6_flowlabel_req freq; 520 struct ipv6_fl_socklist *sfl1 = NULL; 521 struct ipv6_fl_socklist *sfl; 522 struct ipv6_fl_socklist __rcu **sflp; 523 struct ip6_flowlabel *fl, *fl1 = NULL; 524 525 526 if (optlen < sizeof(freq)) 527 return -EINVAL; 528 529 if (copy_from_user(&freq, optval, sizeof(freq))) 530 return -EFAULT; 531 532 switch (freq.flr_action) { 533 case IPV6_FL_A_PUT: 534 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 535 if (sk->sk_protocol != IPPROTO_TCP) 536 return -ENOPROTOOPT; 537 if (!np->repflow) 538 return -ESRCH; 539 np->flow_label = 0; 540 np->repflow = 0; 541 return 0; 542 } 543 spin_lock_bh(&ip6_sk_fl_lock); 544 for (sflp = &np->ipv6_fl_list; 545 (sfl = rcu_dereference_protected(*sflp, 546 lockdep_is_held(&ip6_sk_fl_lock))) != NULL; 547 sflp = &sfl->next) { 548 if (sfl->fl->label == freq.flr_label) { 549 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK)) 550 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 551 *sflp = sfl->next; 552 spin_unlock_bh(&ip6_sk_fl_lock); 553 fl_release(sfl->fl); 554 kfree_rcu(sfl, rcu); 555 return 0; 556 } 557 } 558 spin_unlock_bh(&ip6_sk_fl_lock); 559 return -ESRCH; 560 561 case IPV6_FL_A_RENEW: 562 rcu_read_lock_bh(); 563 for_each_sk_fl_rcu(np, sfl) { 564 if (sfl->fl->label == freq.flr_label) { 565 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires); 566 rcu_read_unlock_bh(); 567 return err; 568 } 569 } 570 rcu_read_unlock_bh(); 571 572 if (freq.flr_share == IPV6_FL_S_NONE && 573 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 574 fl = fl_lookup(net, freq.flr_label); 575 if (fl) { 576 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires); 577 fl_release(fl); 578 return err; 579 } 580 } 581 return -ESRCH; 582 583 case IPV6_FL_A_GET: 584 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 585 struct net *net = sock_net(sk); 586 if (net->ipv6.sysctl.flowlabel_consistency) { 587 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 588 return -EPERM; 589 } 590 591 if (sk->sk_protocol != IPPROTO_TCP) 592 return -ENOPROTOOPT; 593 594 np->repflow = 1; 595 return 0; 596 } 597 598 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK) 599 return -EINVAL; 600 601 if (net->ipv6.sysctl.flowlabel_state_ranges && 602 (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 603 return -ERANGE; 604 605 fl = fl_create(net, sk, &freq, optval, optlen, &err); 606 if (!fl) 607 return err; 608 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 609 610 if (freq.flr_label) { 611 err = -EEXIST; 612 rcu_read_lock_bh(); 613 for_each_sk_fl_rcu(np, sfl) { 614 if (sfl->fl->label == freq.flr_label) { 615 if (freq.flr_flags&IPV6_FL_F_EXCL) { 616 rcu_read_unlock_bh(); 617 goto done; 618 } 619 fl1 = sfl->fl; 620 atomic_inc(&fl1->users); 621 break; 622 } 623 } 624 rcu_read_unlock_bh(); 625 626 if (!fl1) 627 fl1 = fl_lookup(net, freq.flr_label); 628 if (fl1) { 629 recheck: 630 err = -EEXIST; 631 if (freq.flr_flags&IPV6_FL_F_EXCL) 632 goto release; 633 err = -EPERM; 634 if (fl1->share == IPV6_FL_S_EXCL || 635 fl1->share != fl->share || 636 ((fl1->share == IPV6_FL_S_PROCESS) && 637 (fl1->owner.pid == fl->owner.pid)) || 638 ((fl1->share == IPV6_FL_S_USER) && 639 uid_eq(fl1->owner.uid, fl->owner.uid))) 640 goto release; 641 642 err = -ENOMEM; 643 if (!sfl1) 644 goto release; 645 if (fl->linger > fl1->linger) 646 fl1->linger = fl->linger; 647 if ((long)(fl->expires - fl1->expires) > 0) 648 fl1->expires = fl->expires; 649 fl_link(np, sfl1, fl1); 650 fl_free(fl); 651 return 0; 652 653 release: 654 fl_release(fl1); 655 goto done; 656 } 657 } 658 err = -ENOENT; 659 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 660 goto done; 661 662 err = -ENOMEM; 663 if (!sfl1) 664 goto done; 665 666 err = mem_check(sk); 667 if (err != 0) 668 goto done; 669 670 fl1 = fl_intern(net, fl, freq.flr_label); 671 if (fl1) 672 goto recheck; 673 674 if (!freq.flr_label) { 675 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 676 &fl->label, sizeof(fl->label))) { 677 /* Intentionally ignore fault. */ 678 } 679 } 680 681 fl_link(np, sfl1, fl); 682 return 0; 683 684 default: 685 return -EINVAL; 686 } 687 688 done: 689 fl_free(fl); 690 kfree(sfl1); 691 return err; 692 } 693 694 #ifdef CONFIG_PROC_FS 695 696 struct ip6fl_iter_state { 697 struct seq_net_private p; 698 struct pid_namespace *pid_ns; 699 int bucket; 700 }; 701 702 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 703 704 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 705 { 706 struct ip6_flowlabel *fl = NULL; 707 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 708 struct net *net = seq_file_net(seq); 709 710 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 711 for_each_fl_rcu(state->bucket, fl) { 712 if (net_eq(fl->fl_net, net)) 713 goto out; 714 } 715 } 716 fl = NULL; 717 out: 718 return fl; 719 } 720 721 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 722 { 723 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 724 struct net *net = seq_file_net(seq); 725 726 for_each_fl_continue_rcu(fl) { 727 if (net_eq(fl->fl_net, net)) 728 goto out; 729 } 730 731 try_again: 732 if (++state->bucket <= FL_HASH_MASK) { 733 for_each_fl_rcu(state->bucket, fl) { 734 if (net_eq(fl->fl_net, net)) 735 goto out; 736 } 737 goto try_again; 738 } 739 fl = NULL; 740 741 out: 742 return fl; 743 } 744 745 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 746 { 747 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 748 if (fl) 749 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 750 --pos; 751 return pos ? NULL : fl; 752 } 753 754 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 755 __acquires(RCU) 756 { 757 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 758 759 state->pid_ns = proc_pid_ns(file_inode(seq->file)); 760 761 rcu_read_lock_bh(); 762 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 763 } 764 765 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 766 { 767 struct ip6_flowlabel *fl; 768 769 if (v == SEQ_START_TOKEN) 770 fl = ip6fl_get_first(seq); 771 else 772 fl = ip6fl_get_next(seq, v); 773 ++*pos; 774 return fl; 775 } 776 777 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 778 __releases(RCU) 779 { 780 rcu_read_unlock_bh(); 781 } 782 783 static int ip6fl_seq_show(struct seq_file *seq, void *v) 784 { 785 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 786 if (v == SEQ_START_TOKEN) { 787 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 788 } else { 789 struct ip6_flowlabel *fl = v; 790 seq_printf(seq, 791 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 792 (unsigned int)ntohl(fl->label), 793 fl->share, 794 ((fl->share == IPV6_FL_S_PROCESS) ? 795 pid_nr_ns(fl->owner.pid, state->pid_ns) : 796 ((fl->share == IPV6_FL_S_USER) ? 797 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 798 0)), 799 atomic_read(&fl->users), 800 fl->linger/HZ, 801 (long)(fl->expires - jiffies)/HZ, 802 &fl->dst, 803 fl->opt ? fl->opt->opt_nflen : 0); 804 } 805 return 0; 806 } 807 808 static const struct seq_operations ip6fl_seq_ops = { 809 .start = ip6fl_seq_start, 810 .next = ip6fl_seq_next, 811 .stop = ip6fl_seq_stop, 812 .show = ip6fl_seq_show, 813 }; 814 815 static int __net_init ip6_flowlabel_proc_init(struct net *net) 816 { 817 if (!proc_create_net("ip6_flowlabel", 0444, net->proc_net, 818 &ip6fl_seq_ops, sizeof(struct ip6fl_iter_state))) 819 return -ENOMEM; 820 return 0; 821 } 822 823 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 824 { 825 remove_proc_entry("ip6_flowlabel", net->proc_net); 826 } 827 #else 828 static inline int ip6_flowlabel_proc_init(struct net *net) 829 { 830 return 0; 831 } 832 static inline void ip6_flowlabel_proc_fini(struct net *net) 833 { 834 } 835 #endif 836 837 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 838 { 839 ip6_fl_purge(net); 840 ip6_flowlabel_proc_fini(net); 841 } 842 843 static struct pernet_operations ip6_flowlabel_net_ops = { 844 .init = ip6_flowlabel_proc_init, 845 .exit = ip6_flowlabel_net_exit, 846 }; 847 848 int ip6_flowlabel_init(void) 849 { 850 return register_pernet_subsys(&ip6_flowlabel_net_ops); 851 } 852 853 void ip6_flowlabel_cleanup(void) 854 { 855 del_timer(&ip6_fl_gc_timer); 856 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 857 } 858