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