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/addrconf.h> 30 #include <net/rawv6.h> 31 #include <net/transp_v6.h> 32 33 #include <asm/uaccess.h> 34 35 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified 36 in old IPv6 RFC. Well, it was reasonable value. 37 */ 38 #define FL_MAX_LINGER 150 /* Maximal linger timeout */ 39 40 /* FL hash table */ 41 42 #define FL_MAX_PER_SOCK 32 43 #define FL_MAX_SIZE 4096 44 #define FL_HASH_MASK 255 45 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK) 46 47 static atomic_t fl_size = ATOMIC_INIT(0); 48 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1]; 49 50 static void ip6_fl_gc(unsigned long dummy); 51 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0); 52 53 /* FL hash table lock: it protects only of GC */ 54 55 static DEFINE_SPINLOCK(ip6_fl_lock); 56 57 /* Big socket sock */ 58 59 static DEFINE_SPINLOCK(ip6_sk_fl_lock); 60 61 #define for_each_fl_rcu(hash, fl) \ 62 for (fl = rcu_dereference_bh(fl_ht[(hash)]); \ 63 fl != NULL; \ 64 fl = rcu_dereference_bh(fl->next)) 65 #define for_each_fl_continue_rcu(fl) \ 66 for (fl = rcu_dereference_bh(fl->next); \ 67 fl != NULL; \ 68 fl = rcu_dereference_bh(fl->next)) 69 70 #define for_each_sk_fl_rcu(np, sfl) \ 71 for (sfl = rcu_dereference_bh(np->ipv6_fl_list); \ 72 sfl != NULL; \ 73 sfl = rcu_dereference_bh(sfl->next)) 74 75 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label) 76 { 77 struct ip6_flowlabel *fl; 78 79 for_each_fl_rcu(FL_HASH(label), fl) { 80 if (fl->label == label && net_eq(fl->fl_net, net)) 81 return fl; 82 } 83 return NULL; 84 } 85 86 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) 87 { 88 struct ip6_flowlabel *fl; 89 90 rcu_read_lock_bh(); 91 fl = __fl_lookup(net, label); 92 if (fl && !atomic_inc_not_zero(&fl->users)) 93 fl = NULL; 94 rcu_read_unlock_bh(); 95 return fl; 96 } 97 98 99 static void fl_free(struct ip6_flowlabel *fl) 100 { 101 if (fl) { 102 if (fl->share == IPV6_FL_S_PROCESS) 103 put_pid(fl->owner.pid); 104 release_net(fl->fl_net); 105 kfree(fl->opt); 106 kfree_rcu(fl, rcu); 107 } 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(unsigned long dummy) 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(&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(&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 == NULL) 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 != NULL) { 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 } 263 264 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 265 266 void fl6_free_socklist(struct sock *sk) 267 { 268 struct ipv6_pinfo *np = inet6_sk(sk); 269 struct ipv6_fl_socklist *sfl; 270 271 if (!rcu_access_pointer(np->ipv6_fl_list)) 272 return; 273 274 spin_lock_bh(&ip6_sk_fl_lock); 275 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 276 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 277 np->ipv6_fl_list = sfl->next; 278 spin_unlock_bh(&ip6_sk_fl_lock); 279 280 fl_release(sfl->fl); 281 kfree_rcu(sfl, rcu); 282 283 spin_lock_bh(&ip6_sk_fl_lock); 284 } 285 spin_unlock_bh(&ip6_sk_fl_lock); 286 } 287 288 /* Service routines */ 289 290 291 /* 292 It is the only difficult place. flowlabel enforces equal headers 293 before and including routing header, however user may supply options 294 following rthdr. 295 */ 296 297 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space, 298 struct ip6_flowlabel * fl, 299 struct ipv6_txoptions * fopt) 300 { 301 struct ipv6_txoptions * fl_opt = fl->opt; 302 303 if (fopt == NULL || fopt->opt_flen == 0) 304 return fl_opt; 305 306 if (fl_opt != NULL) { 307 opt_space->hopopt = fl_opt->hopopt; 308 opt_space->dst0opt = fl_opt->dst0opt; 309 opt_space->srcrt = fl_opt->srcrt; 310 opt_space->opt_nflen = fl_opt->opt_nflen; 311 } else { 312 if (fopt->opt_nflen == 0) 313 return fopt; 314 opt_space->hopopt = NULL; 315 opt_space->dst0opt = NULL; 316 opt_space->srcrt = NULL; 317 opt_space->opt_nflen = 0; 318 } 319 opt_space->dst1opt = fopt->dst1opt; 320 opt_space->opt_flen = fopt->opt_flen; 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 == NULL) 373 goto done; 374 375 if (olen > 0) { 376 struct msghdr msg; 377 struct flowi6 flowi6; 378 int junk; 379 380 err = -ENOMEM; 381 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 382 if (fl->opt == NULL) 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 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, fl->opt, 396 &junk, &junk, &junk); 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 = hold_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(*sflp))!=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 = rcu_dereference(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 fl = fl_create(net, sk, &freq, optval, optlen, &err); 602 if (fl == NULL) 603 return err; 604 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 605 606 if (freq.flr_label) { 607 err = -EEXIST; 608 rcu_read_lock_bh(); 609 for_each_sk_fl_rcu(np, sfl) { 610 if (sfl->fl->label == freq.flr_label) { 611 if (freq.flr_flags&IPV6_FL_F_EXCL) { 612 rcu_read_unlock_bh(); 613 goto done; 614 } 615 fl1 = sfl->fl; 616 atomic_inc(&fl1->users); 617 break; 618 } 619 } 620 rcu_read_unlock_bh(); 621 622 if (fl1 == NULL) 623 fl1 = fl_lookup(net, freq.flr_label); 624 if (fl1) { 625 recheck: 626 err = -EEXIST; 627 if (freq.flr_flags&IPV6_FL_F_EXCL) 628 goto release; 629 err = -EPERM; 630 if (fl1->share == IPV6_FL_S_EXCL || 631 fl1->share != fl->share || 632 ((fl1->share == IPV6_FL_S_PROCESS) && 633 (fl1->owner.pid == fl->owner.pid)) || 634 ((fl1->share == IPV6_FL_S_USER) && 635 uid_eq(fl1->owner.uid, fl->owner.uid))) 636 goto release; 637 638 err = -ENOMEM; 639 if (sfl1 == NULL) 640 goto release; 641 if (fl->linger > fl1->linger) 642 fl1->linger = fl->linger; 643 if ((long)(fl->expires - fl1->expires) > 0) 644 fl1->expires = fl->expires; 645 fl_link(np, sfl1, fl1); 646 fl_free(fl); 647 return 0; 648 649 release: 650 fl_release(fl1); 651 goto done; 652 } 653 } 654 err = -ENOENT; 655 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 656 goto done; 657 658 err = -ENOMEM; 659 if (sfl1 == NULL || (err = mem_check(sk)) != 0) 660 goto done; 661 662 fl1 = fl_intern(net, fl, freq.flr_label); 663 if (fl1 != NULL) 664 goto recheck; 665 666 if (!freq.flr_label) { 667 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 668 &fl->label, sizeof(fl->label))) { 669 /* Intentionally ignore fault. */ 670 } 671 } 672 673 fl_link(np, sfl1, fl); 674 return 0; 675 676 default: 677 return -EINVAL; 678 } 679 680 done: 681 fl_free(fl); 682 kfree(sfl1); 683 return err; 684 } 685 686 #ifdef CONFIG_PROC_FS 687 688 struct ip6fl_iter_state { 689 struct seq_net_private p; 690 struct pid_namespace *pid_ns; 691 int bucket; 692 }; 693 694 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 695 696 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 697 { 698 struct ip6_flowlabel *fl = NULL; 699 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 700 struct net *net = seq_file_net(seq); 701 702 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 703 for_each_fl_rcu(state->bucket, fl) { 704 if (net_eq(fl->fl_net, net)) 705 goto out; 706 } 707 } 708 fl = NULL; 709 out: 710 return fl; 711 } 712 713 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 714 { 715 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 716 struct net *net = seq_file_net(seq); 717 718 for_each_fl_continue_rcu(fl) { 719 if (net_eq(fl->fl_net, net)) 720 goto out; 721 } 722 723 try_again: 724 if (++state->bucket <= FL_HASH_MASK) { 725 for_each_fl_rcu(state->bucket, fl) { 726 if (net_eq(fl->fl_net, net)) 727 goto out; 728 } 729 goto try_again; 730 } 731 fl = NULL; 732 733 out: 734 return fl; 735 } 736 737 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 738 { 739 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 740 if (fl) 741 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 742 --pos; 743 return pos ? NULL : fl; 744 } 745 746 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 747 __acquires(RCU) 748 { 749 rcu_read_lock_bh(); 750 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 751 } 752 753 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 754 { 755 struct ip6_flowlabel *fl; 756 757 if (v == SEQ_START_TOKEN) 758 fl = ip6fl_get_first(seq); 759 else 760 fl = ip6fl_get_next(seq, v); 761 ++*pos; 762 return fl; 763 } 764 765 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 766 __releases(RCU) 767 { 768 rcu_read_unlock_bh(); 769 } 770 771 static int ip6fl_seq_show(struct seq_file *seq, void *v) 772 { 773 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 774 if (v == SEQ_START_TOKEN) 775 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n", 776 "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt"); 777 else { 778 struct ip6_flowlabel *fl = v; 779 seq_printf(seq, 780 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 781 (unsigned int)ntohl(fl->label), 782 fl->share, 783 ((fl->share == IPV6_FL_S_PROCESS) ? 784 pid_nr_ns(fl->owner.pid, state->pid_ns) : 785 ((fl->share == IPV6_FL_S_USER) ? 786 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 787 0)), 788 atomic_read(&fl->users), 789 fl->linger/HZ, 790 (long)(fl->expires - jiffies)/HZ, 791 &fl->dst, 792 fl->opt ? fl->opt->opt_nflen : 0); 793 } 794 return 0; 795 } 796 797 static const struct seq_operations ip6fl_seq_ops = { 798 .start = ip6fl_seq_start, 799 .next = ip6fl_seq_next, 800 .stop = ip6fl_seq_stop, 801 .show = ip6fl_seq_show, 802 }; 803 804 static int ip6fl_seq_open(struct inode *inode, struct file *file) 805 { 806 struct seq_file *seq; 807 struct ip6fl_iter_state *state; 808 int err; 809 810 err = seq_open_net(inode, file, &ip6fl_seq_ops, 811 sizeof(struct ip6fl_iter_state)); 812 813 if (!err) { 814 seq = file->private_data; 815 state = ip6fl_seq_private(seq); 816 rcu_read_lock(); 817 state->pid_ns = get_pid_ns(task_active_pid_ns(current)); 818 rcu_read_unlock(); 819 } 820 return err; 821 } 822 823 static int ip6fl_seq_release(struct inode *inode, struct file *file) 824 { 825 struct seq_file *seq = file->private_data; 826 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 827 put_pid_ns(state->pid_ns); 828 return seq_release_net(inode, file); 829 } 830 831 static const struct file_operations ip6fl_seq_fops = { 832 .owner = THIS_MODULE, 833 .open = ip6fl_seq_open, 834 .read = seq_read, 835 .llseek = seq_lseek, 836 .release = ip6fl_seq_release, 837 }; 838 839 static int __net_init ip6_flowlabel_proc_init(struct net *net) 840 { 841 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net, 842 &ip6fl_seq_fops)) 843 return -ENOMEM; 844 return 0; 845 } 846 847 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 848 { 849 remove_proc_entry("ip6_flowlabel", net->proc_net); 850 } 851 #else 852 static inline int ip6_flowlabel_proc_init(struct net *net) 853 { 854 return 0; 855 } 856 static inline void ip6_flowlabel_proc_fini(struct net *net) 857 { 858 } 859 #endif 860 861 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 862 { 863 ip6_fl_purge(net); 864 ip6_flowlabel_proc_fini(net); 865 } 866 867 static struct pernet_operations ip6_flowlabel_net_ops = { 868 .init = ip6_flowlabel_proc_init, 869 .exit = ip6_flowlabel_net_exit, 870 }; 871 872 int ip6_flowlabel_init(void) 873 { 874 return register_pernet_subsys(&ip6_flowlabel_net_ops); 875 } 876 877 void ip6_flowlabel_cleanup(void) 878 { 879 del_timer(&ip6_fl_gc_timer); 880 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 881 } 882