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 static void fl_free_rcu(struct rcu_head *head) 98 { 99 struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu); 100 101 if (fl->share == IPV6_FL_S_PROCESS) 102 put_pid(fl->owner.pid); 103 kfree(fl->opt); 104 kfree(fl); 105 } 106 107 108 static void fl_free(struct ip6_flowlabel *fl) 109 { 110 if (fl) 111 call_rcu(&fl->rcu, fl_free_rcu); 112 } 113 114 static void fl_release(struct ip6_flowlabel *fl) 115 { 116 spin_lock_bh(&ip6_fl_lock); 117 118 fl->lastuse = jiffies; 119 if (atomic_dec_and_test(&fl->users)) { 120 unsigned long ttd = fl->lastuse + fl->linger; 121 if (time_after(ttd, fl->expires)) 122 fl->expires = ttd; 123 ttd = fl->expires; 124 if (fl->opt && fl->share == IPV6_FL_S_EXCL) { 125 struct ipv6_txoptions *opt = fl->opt; 126 fl->opt = NULL; 127 kfree(opt); 128 } 129 if (!timer_pending(&ip6_fl_gc_timer) || 130 time_after(ip6_fl_gc_timer.expires, ttd)) 131 mod_timer(&ip6_fl_gc_timer, ttd); 132 } 133 spin_unlock_bh(&ip6_fl_lock); 134 } 135 136 static void ip6_fl_gc(struct timer_list *unused) 137 { 138 int i; 139 unsigned long now = jiffies; 140 unsigned long sched = 0; 141 142 spin_lock(&ip6_fl_lock); 143 144 for (i = 0; i <= FL_HASH_MASK; i++) { 145 struct ip6_flowlabel *fl; 146 struct ip6_flowlabel __rcu **flp; 147 148 flp = &fl_ht[i]; 149 while ((fl = rcu_dereference_protected(*flp, 150 lockdep_is_held(&ip6_fl_lock))) != NULL) { 151 if (atomic_read(&fl->users) == 0) { 152 unsigned long ttd = fl->lastuse + fl->linger; 153 if (time_after(ttd, fl->expires)) 154 fl->expires = ttd; 155 ttd = fl->expires; 156 if (time_after_eq(now, ttd)) { 157 *flp = fl->next; 158 fl_free(fl); 159 atomic_dec(&fl_size); 160 continue; 161 } 162 if (!sched || time_before(ttd, sched)) 163 sched = ttd; 164 } 165 flp = &fl->next; 166 } 167 } 168 if (!sched && atomic_read(&fl_size)) 169 sched = now + FL_MAX_LINGER; 170 if (sched) { 171 mod_timer(&ip6_fl_gc_timer, sched); 172 } 173 spin_unlock(&ip6_fl_lock); 174 } 175 176 static void __net_exit ip6_fl_purge(struct net *net) 177 { 178 int i; 179 180 spin_lock_bh(&ip6_fl_lock); 181 for (i = 0; i <= FL_HASH_MASK; i++) { 182 struct ip6_flowlabel *fl; 183 struct ip6_flowlabel __rcu **flp; 184 185 flp = &fl_ht[i]; 186 while ((fl = rcu_dereference_protected(*flp, 187 lockdep_is_held(&ip6_fl_lock))) != NULL) { 188 if (net_eq(fl->fl_net, net) && 189 atomic_read(&fl->users) == 0) { 190 *flp = fl->next; 191 fl_free(fl); 192 atomic_dec(&fl_size); 193 continue; 194 } 195 flp = &fl->next; 196 } 197 } 198 spin_unlock_bh(&ip6_fl_lock); 199 } 200 201 static struct ip6_flowlabel *fl_intern(struct net *net, 202 struct ip6_flowlabel *fl, __be32 label) 203 { 204 struct ip6_flowlabel *lfl; 205 206 fl->label = label & IPV6_FLOWLABEL_MASK; 207 208 spin_lock_bh(&ip6_fl_lock); 209 if (label == 0) { 210 for (;;) { 211 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK; 212 if (fl->label) { 213 lfl = __fl_lookup(net, fl->label); 214 if (!lfl) 215 break; 216 } 217 } 218 } else { 219 /* 220 * we dropper the ip6_fl_lock, so this entry could reappear 221 * and we need to recheck with it. 222 * 223 * OTOH no need to search the active socket first, like it is 224 * done in ipv6_flowlabel_opt - sock is locked, so new entry 225 * with the same label can only appear on another sock 226 */ 227 lfl = __fl_lookup(net, fl->label); 228 if (lfl) { 229 atomic_inc(&lfl->users); 230 spin_unlock_bh(&ip6_fl_lock); 231 return lfl; 232 } 233 } 234 235 fl->lastuse = jiffies; 236 fl->next = fl_ht[FL_HASH(fl->label)]; 237 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 238 atomic_inc(&fl_size); 239 spin_unlock_bh(&ip6_fl_lock); 240 return NULL; 241 } 242 243 244 245 /* Socket flowlabel lists */ 246 247 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label) 248 { 249 struct ipv6_fl_socklist *sfl; 250 struct ipv6_pinfo *np = inet6_sk(sk); 251 252 label &= IPV6_FLOWLABEL_MASK; 253 254 rcu_read_lock_bh(); 255 for_each_sk_fl_rcu(np, sfl) { 256 struct ip6_flowlabel *fl = sfl->fl; 257 if (fl->label == label) { 258 fl->lastuse = jiffies; 259 atomic_inc(&fl->users); 260 rcu_read_unlock_bh(); 261 return fl; 262 } 263 } 264 rcu_read_unlock_bh(); 265 return NULL; 266 } 267 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 268 269 void fl6_free_socklist(struct sock *sk) 270 { 271 struct ipv6_pinfo *np = inet6_sk(sk); 272 struct ipv6_fl_socklist *sfl; 273 274 if (!rcu_access_pointer(np->ipv6_fl_list)) 275 return; 276 277 spin_lock_bh(&ip6_sk_fl_lock); 278 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 279 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 280 np->ipv6_fl_list = sfl->next; 281 spin_unlock_bh(&ip6_sk_fl_lock); 282 283 fl_release(sfl->fl); 284 kfree_rcu(sfl, rcu); 285 286 spin_lock_bh(&ip6_sk_fl_lock); 287 } 288 spin_unlock_bh(&ip6_sk_fl_lock); 289 } 290 291 /* Service routines */ 292 293 294 /* 295 It is the only difficult place. flowlabel enforces equal headers 296 before and including routing header, however user may supply options 297 following rthdr. 298 */ 299 300 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 301 struct ip6_flowlabel *fl, 302 struct ipv6_txoptions *fopt) 303 { 304 struct ipv6_txoptions *fl_opt = fl->opt; 305 306 if (!fopt || fopt->opt_flen == 0) 307 return fl_opt; 308 309 if (fl_opt) { 310 opt_space->hopopt = fl_opt->hopopt; 311 opt_space->dst0opt = fl_opt->dst0opt; 312 opt_space->srcrt = fl_opt->srcrt; 313 opt_space->opt_nflen = fl_opt->opt_nflen; 314 } else { 315 if (fopt->opt_nflen == 0) 316 return fopt; 317 opt_space->hopopt = NULL; 318 opt_space->dst0opt = NULL; 319 opt_space->srcrt = NULL; 320 opt_space->opt_nflen = 0; 321 } 322 opt_space->dst1opt = fopt->dst1opt; 323 opt_space->opt_flen = fopt->opt_flen; 324 opt_space->tot_len = fopt->tot_len; 325 return opt_space; 326 } 327 EXPORT_SYMBOL_GPL(fl6_merge_options); 328 329 static unsigned long check_linger(unsigned long ttl) 330 { 331 if (ttl < FL_MIN_LINGER) 332 return FL_MIN_LINGER*HZ; 333 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 334 return 0; 335 return ttl*HZ; 336 } 337 338 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 339 { 340 linger = check_linger(linger); 341 if (!linger) 342 return -EPERM; 343 expires = check_linger(expires); 344 if (!expires) 345 return -EPERM; 346 347 spin_lock_bh(&ip6_fl_lock); 348 fl->lastuse = jiffies; 349 if (time_before(fl->linger, linger)) 350 fl->linger = linger; 351 if (time_before(expires, fl->linger)) 352 expires = fl->linger; 353 if (time_before(fl->expires, fl->lastuse + expires)) 354 fl->expires = fl->lastuse + expires; 355 spin_unlock_bh(&ip6_fl_lock); 356 357 return 0; 358 } 359 360 static struct ip6_flowlabel * 361 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 362 char __user *optval, int optlen, int *err_p) 363 { 364 struct ip6_flowlabel *fl = NULL; 365 int olen; 366 int addr_type; 367 int err; 368 369 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 370 err = -EINVAL; 371 if (olen > 64 * 1024) 372 goto done; 373 374 err = -ENOMEM; 375 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 376 if (!fl) 377 goto done; 378 379 if (olen > 0) { 380 struct msghdr msg; 381 struct flowi6 flowi6; 382 struct ipcm6_cookie ipc6; 383 384 err = -ENOMEM; 385 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 386 if (!fl->opt) 387 goto done; 388 389 memset(fl->opt, 0, sizeof(*fl->opt)); 390 fl->opt->tot_len = sizeof(*fl->opt) + olen; 391 err = -EFAULT; 392 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen)) 393 goto done; 394 395 msg.msg_controllen = olen; 396 msg.msg_control = (void *)(fl->opt+1); 397 memset(&flowi6, 0, sizeof(flowi6)); 398 399 ipc6.opt = fl->opt; 400 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6); 401 if (err) 402 goto done; 403 err = -EINVAL; 404 if (fl->opt->opt_flen) 405 goto done; 406 if (fl->opt->opt_nflen == 0) { 407 kfree(fl->opt); 408 fl->opt = NULL; 409 } 410 } 411 412 fl->fl_net = net; 413 fl->expires = jiffies; 414 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 415 if (err) 416 goto done; 417 fl->share = freq->flr_share; 418 addr_type = ipv6_addr_type(&freq->flr_dst); 419 if ((addr_type & IPV6_ADDR_MAPPED) || 420 addr_type == IPV6_ADDR_ANY) { 421 err = -EINVAL; 422 goto done; 423 } 424 fl->dst = freq->flr_dst; 425 atomic_set(&fl->users, 1); 426 switch (fl->share) { 427 case IPV6_FL_S_EXCL: 428 case IPV6_FL_S_ANY: 429 break; 430 case IPV6_FL_S_PROCESS: 431 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 432 break; 433 case IPV6_FL_S_USER: 434 fl->owner.uid = current_euid(); 435 break; 436 default: 437 err = -EINVAL; 438 goto done; 439 } 440 return fl; 441 442 done: 443 fl_free(fl); 444 *err_p = err; 445 return NULL; 446 } 447 448 static int mem_check(struct sock *sk) 449 { 450 struct ipv6_pinfo *np = inet6_sk(sk); 451 struct ipv6_fl_socklist *sfl; 452 int room = FL_MAX_SIZE - atomic_read(&fl_size); 453 int count = 0; 454 455 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 456 return 0; 457 458 rcu_read_lock_bh(); 459 for_each_sk_fl_rcu(np, sfl) 460 count++; 461 rcu_read_unlock_bh(); 462 463 if (room <= 0 || 464 ((count >= FL_MAX_PER_SOCK || 465 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 466 !capable(CAP_NET_ADMIN))) 467 return -ENOBUFS; 468 469 return 0; 470 } 471 472 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 473 struct ip6_flowlabel *fl) 474 { 475 spin_lock_bh(&ip6_sk_fl_lock); 476 sfl->fl = fl; 477 sfl->next = np->ipv6_fl_list; 478 rcu_assign_pointer(np->ipv6_fl_list, sfl); 479 spin_unlock_bh(&ip6_sk_fl_lock); 480 } 481 482 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 483 int flags) 484 { 485 struct ipv6_pinfo *np = inet6_sk(sk); 486 struct ipv6_fl_socklist *sfl; 487 488 if (flags & IPV6_FL_F_REMOTE) { 489 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 490 return 0; 491 } 492 493 if (np->repflow) { 494 freq->flr_label = np->flow_label; 495 return 0; 496 } 497 498 rcu_read_lock_bh(); 499 500 for_each_sk_fl_rcu(np, sfl) { 501 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 502 spin_lock_bh(&ip6_fl_lock); 503 freq->flr_label = sfl->fl->label; 504 freq->flr_dst = sfl->fl->dst; 505 freq->flr_share = sfl->fl->share; 506 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 507 freq->flr_linger = sfl->fl->linger / HZ; 508 509 spin_unlock_bh(&ip6_fl_lock); 510 rcu_read_unlock_bh(); 511 return 0; 512 } 513 } 514 rcu_read_unlock_bh(); 515 516 return -ENOENT; 517 } 518 519 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen) 520 { 521 int uninitialized_var(err); 522 struct net *net = sock_net(sk); 523 struct ipv6_pinfo *np = inet6_sk(sk); 524 struct in6_flowlabel_req freq; 525 struct ipv6_fl_socklist *sfl1 = NULL; 526 struct ipv6_fl_socklist *sfl; 527 struct ipv6_fl_socklist __rcu **sflp; 528 struct ip6_flowlabel *fl, *fl1 = NULL; 529 530 531 if (optlen < sizeof(freq)) 532 return -EINVAL; 533 534 if (copy_from_user(&freq, optval, sizeof(freq))) 535 return -EFAULT; 536 537 switch (freq.flr_action) { 538 case IPV6_FL_A_PUT: 539 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 540 if (sk->sk_protocol != IPPROTO_TCP) 541 return -ENOPROTOOPT; 542 if (!np->repflow) 543 return -ESRCH; 544 np->flow_label = 0; 545 np->repflow = 0; 546 return 0; 547 } 548 spin_lock_bh(&ip6_sk_fl_lock); 549 for (sflp = &np->ipv6_fl_list; 550 (sfl = rcu_dereference_protected(*sflp, 551 lockdep_is_held(&ip6_sk_fl_lock))) != NULL; 552 sflp = &sfl->next) { 553 if (sfl->fl->label == freq.flr_label) { 554 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK)) 555 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 556 *sflp = sfl->next; 557 spin_unlock_bh(&ip6_sk_fl_lock); 558 fl_release(sfl->fl); 559 kfree_rcu(sfl, rcu); 560 return 0; 561 } 562 } 563 spin_unlock_bh(&ip6_sk_fl_lock); 564 return -ESRCH; 565 566 case IPV6_FL_A_RENEW: 567 rcu_read_lock_bh(); 568 for_each_sk_fl_rcu(np, sfl) { 569 if (sfl->fl->label == freq.flr_label) { 570 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires); 571 rcu_read_unlock_bh(); 572 return err; 573 } 574 } 575 rcu_read_unlock_bh(); 576 577 if (freq.flr_share == IPV6_FL_S_NONE && 578 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 579 fl = fl_lookup(net, freq.flr_label); 580 if (fl) { 581 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires); 582 fl_release(fl); 583 return err; 584 } 585 } 586 return -ESRCH; 587 588 case IPV6_FL_A_GET: 589 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 590 struct net *net = sock_net(sk); 591 if (net->ipv6.sysctl.flowlabel_consistency) { 592 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 593 return -EPERM; 594 } 595 596 if (sk->sk_protocol != IPPROTO_TCP) 597 return -ENOPROTOOPT; 598 599 np->repflow = 1; 600 return 0; 601 } 602 603 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK) 604 return -EINVAL; 605 606 if (net->ipv6.sysctl.flowlabel_state_ranges && 607 (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 608 return -ERANGE; 609 610 fl = fl_create(net, sk, &freq, optval, optlen, &err); 611 if (!fl) 612 return err; 613 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 614 615 if (freq.flr_label) { 616 err = -EEXIST; 617 rcu_read_lock_bh(); 618 for_each_sk_fl_rcu(np, sfl) { 619 if (sfl->fl->label == freq.flr_label) { 620 if (freq.flr_flags&IPV6_FL_F_EXCL) { 621 rcu_read_unlock_bh(); 622 goto done; 623 } 624 fl1 = sfl->fl; 625 atomic_inc(&fl1->users); 626 break; 627 } 628 } 629 rcu_read_unlock_bh(); 630 631 if (!fl1) 632 fl1 = fl_lookup(net, freq.flr_label); 633 if (fl1) { 634 recheck: 635 err = -EEXIST; 636 if (freq.flr_flags&IPV6_FL_F_EXCL) 637 goto release; 638 err = -EPERM; 639 if (fl1->share == IPV6_FL_S_EXCL || 640 fl1->share != fl->share || 641 ((fl1->share == IPV6_FL_S_PROCESS) && 642 (fl1->owner.pid != fl->owner.pid)) || 643 ((fl1->share == IPV6_FL_S_USER) && 644 !uid_eq(fl1->owner.uid, fl->owner.uid))) 645 goto release; 646 647 err = -ENOMEM; 648 if (!sfl1) 649 goto release; 650 if (fl->linger > fl1->linger) 651 fl1->linger = fl->linger; 652 if ((long)(fl->expires - fl1->expires) > 0) 653 fl1->expires = fl->expires; 654 fl_link(np, sfl1, fl1); 655 fl_free(fl); 656 return 0; 657 658 release: 659 fl_release(fl1); 660 goto done; 661 } 662 } 663 err = -ENOENT; 664 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 665 goto done; 666 667 err = -ENOMEM; 668 if (!sfl1) 669 goto done; 670 671 err = mem_check(sk); 672 if (err != 0) 673 goto done; 674 675 fl1 = fl_intern(net, fl, freq.flr_label); 676 if (fl1) 677 goto recheck; 678 679 if (!freq.flr_label) { 680 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 681 &fl->label, sizeof(fl->label))) { 682 /* Intentionally ignore fault. */ 683 } 684 } 685 686 fl_link(np, sfl1, fl); 687 return 0; 688 689 default: 690 return -EINVAL; 691 } 692 693 done: 694 fl_free(fl); 695 kfree(sfl1); 696 return err; 697 } 698 699 #ifdef CONFIG_PROC_FS 700 701 struct ip6fl_iter_state { 702 struct seq_net_private p; 703 struct pid_namespace *pid_ns; 704 int bucket; 705 }; 706 707 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 708 709 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 710 { 711 struct ip6_flowlabel *fl = NULL; 712 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 713 struct net *net = seq_file_net(seq); 714 715 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 716 for_each_fl_rcu(state->bucket, fl) { 717 if (net_eq(fl->fl_net, net)) 718 goto out; 719 } 720 } 721 fl = NULL; 722 out: 723 return fl; 724 } 725 726 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 727 { 728 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 729 struct net *net = seq_file_net(seq); 730 731 for_each_fl_continue_rcu(fl) { 732 if (net_eq(fl->fl_net, net)) 733 goto out; 734 } 735 736 try_again: 737 if (++state->bucket <= FL_HASH_MASK) { 738 for_each_fl_rcu(state->bucket, fl) { 739 if (net_eq(fl->fl_net, net)) 740 goto out; 741 } 742 goto try_again; 743 } 744 fl = NULL; 745 746 out: 747 return fl; 748 } 749 750 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 751 { 752 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 753 if (fl) 754 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 755 --pos; 756 return pos ? NULL : fl; 757 } 758 759 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 760 __acquires(RCU) 761 { 762 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 763 764 state->pid_ns = proc_pid_ns(file_inode(seq->file)); 765 766 rcu_read_lock_bh(); 767 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 768 } 769 770 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 771 { 772 struct ip6_flowlabel *fl; 773 774 if (v == SEQ_START_TOKEN) 775 fl = ip6fl_get_first(seq); 776 else 777 fl = ip6fl_get_next(seq, v); 778 ++*pos; 779 return fl; 780 } 781 782 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 783 __releases(RCU) 784 { 785 rcu_read_unlock_bh(); 786 } 787 788 static int ip6fl_seq_show(struct seq_file *seq, void *v) 789 { 790 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 791 if (v == SEQ_START_TOKEN) { 792 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 793 } else { 794 struct ip6_flowlabel *fl = v; 795 seq_printf(seq, 796 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 797 (unsigned int)ntohl(fl->label), 798 fl->share, 799 ((fl->share == IPV6_FL_S_PROCESS) ? 800 pid_nr_ns(fl->owner.pid, state->pid_ns) : 801 ((fl->share == IPV6_FL_S_USER) ? 802 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 803 0)), 804 atomic_read(&fl->users), 805 fl->linger/HZ, 806 (long)(fl->expires - jiffies)/HZ, 807 &fl->dst, 808 fl->opt ? fl->opt->opt_nflen : 0); 809 } 810 return 0; 811 } 812 813 static const struct seq_operations ip6fl_seq_ops = { 814 .start = ip6fl_seq_start, 815 .next = ip6fl_seq_next, 816 .stop = ip6fl_seq_stop, 817 .show = ip6fl_seq_show, 818 }; 819 820 static int __net_init ip6_flowlabel_proc_init(struct net *net) 821 { 822 if (!proc_create_net("ip6_flowlabel", 0444, net->proc_net, 823 &ip6fl_seq_ops, sizeof(struct ip6fl_iter_state))) 824 return -ENOMEM; 825 return 0; 826 } 827 828 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 829 { 830 remove_proc_entry("ip6_flowlabel", net->proc_net); 831 } 832 #else 833 static inline int ip6_flowlabel_proc_init(struct net *net) 834 { 835 return 0; 836 } 837 static inline void ip6_flowlabel_proc_fini(struct net *net) 838 { 839 } 840 #endif 841 842 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 843 { 844 ip6_fl_purge(net); 845 ip6_flowlabel_proc_fini(net); 846 } 847 848 static struct pernet_operations ip6_flowlabel_net_ops = { 849 .init = ip6_flowlabel_proc_init, 850 .exit = ip6_flowlabel_net_exit, 851 }; 852 853 int ip6_flowlabel_init(void) 854 { 855 return register_pernet_subsys(&ip6_flowlabel_net_ops); 856 } 857 858 void ip6_flowlabel_cleanup(void) 859 { 860 del_timer(&ip6_fl_gc_timer); 861 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 862 } 863