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(&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(&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 } 262 263 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 264 265 void fl6_free_socklist(struct sock *sk) 266 { 267 struct ipv6_pinfo *np = inet6_sk(sk); 268 struct ipv6_fl_socklist *sfl; 269 270 if (!rcu_access_pointer(np->ipv6_fl_list)) 271 return; 272 273 spin_lock_bh(&ip6_sk_fl_lock); 274 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 275 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 276 np->ipv6_fl_list = sfl->next; 277 spin_unlock_bh(&ip6_sk_fl_lock); 278 279 fl_release(sfl->fl); 280 kfree_rcu(sfl, rcu); 281 282 spin_lock_bh(&ip6_sk_fl_lock); 283 } 284 spin_unlock_bh(&ip6_sk_fl_lock); 285 } 286 287 /* Service routines */ 288 289 290 /* 291 It is the only difficult place. flowlabel enforces equal headers 292 before and including routing header, however user may supply options 293 following rthdr. 294 */ 295 296 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space, 297 struct ip6_flowlabel * fl, 298 struct ipv6_txoptions * fopt) 299 { 300 struct ipv6_txoptions * fl_opt = fl->opt; 301 302 if (fopt == NULL || fopt->opt_flen == 0) 303 return fl_opt; 304 305 if (fl_opt != NULL) { 306 opt_space->hopopt = fl_opt->hopopt; 307 opt_space->dst0opt = fl_opt->dst0opt; 308 opt_space->srcrt = fl_opt->srcrt; 309 opt_space->opt_nflen = fl_opt->opt_nflen; 310 } else { 311 if (fopt->opt_nflen == 0) 312 return fopt; 313 opt_space->hopopt = NULL; 314 opt_space->dst0opt = NULL; 315 opt_space->srcrt = NULL; 316 opt_space->opt_nflen = 0; 317 } 318 opt_space->dst1opt = fopt->dst1opt; 319 opt_space->opt_flen = fopt->opt_flen; 320 return opt_space; 321 } 322 EXPORT_SYMBOL_GPL(fl6_merge_options); 323 324 static unsigned long check_linger(unsigned long ttl) 325 { 326 if (ttl < FL_MIN_LINGER) 327 return FL_MIN_LINGER*HZ; 328 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 329 return 0; 330 return ttl*HZ; 331 } 332 333 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 334 { 335 linger = check_linger(linger); 336 if (!linger) 337 return -EPERM; 338 expires = check_linger(expires); 339 if (!expires) 340 return -EPERM; 341 342 spin_lock_bh(&ip6_fl_lock); 343 fl->lastuse = jiffies; 344 if (time_before(fl->linger, linger)) 345 fl->linger = linger; 346 if (time_before(expires, fl->linger)) 347 expires = fl->linger; 348 if (time_before(fl->expires, fl->lastuse + expires)) 349 fl->expires = fl->lastuse + expires; 350 spin_unlock_bh(&ip6_fl_lock); 351 352 return 0; 353 } 354 355 static struct ip6_flowlabel * 356 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 357 char __user *optval, int optlen, int *err_p) 358 { 359 struct ip6_flowlabel *fl = NULL; 360 int olen; 361 int addr_type; 362 int err; 363 364 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 365 err = -EINVAL; 366 if (olen > 64 * 1024) 367 goto done; 368 369 err = -ENOMEM; 370 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 371 if (fl == NULL) 372 goto done; 373 374 if (olen > 0) { 375 struct msghdr msg; 376 struct flowi6 flowi6; 377 int junk; 378 379 err = -ENOMEM; 380 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 381 if (fl->opt == NULL) 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 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, fl->opt, 395 &junk, &junk, &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 = hold_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(*sflp))!=NULL; 546 sflp = &sfl->next) { 547 if (sfl->fl->label == freq.flr_label) { 548 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK)) 549 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 550 *sflp = rcu_dereference(sfl->next); 551 spin_unlock_bh(&ip6_sk_fl_lock); 552 fl_release(sfl->fl); 553 kfree_rcu(sfl, rcu); 554 return 0; 555 } 556 } 557 spin_unlock_bh(&ip6_sk_fl_lock); 558 return -ESRCH; 559 560 case IPV6_FL_A_RENEW: 561 rcu_read_lock_bh(); 562 for_each_sk_fl_rcu(np, sfl) { 563 if (sfl->fl->label == freq.flr_label) { 564 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires); 565 rcu_read_unlock_bh(); 566 return err; 567 } 568 } 569 rcu_read_unlock_bh(); 570 571 if (freq.flr_share == IPV6_FL_S_NONE && 572 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 573 fl = fl_lookup(net, freq.flr_label); 574 if (fl) { 575 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires); 576 fl_release(fl); 577 return err; 578 } 579 } 580 return -ESRCH; 581 582 case IPV6_FL_A_GET: 583 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 584 struct net *net = sock_net(sk); 585 if (net->ipv6.sysctl.flowlabel_consistency) { 586 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 587 return -EPERM; 588 } 589 590 if (sk->sk_protocol != IPPROTO_TCP) 591 return -ENOPROTOOPT; 592 593 np->repflow = 1; 594 return 0; 595 } 596 597 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK) 598 return -EINVAL; 599 600 fl = fl_create(net, sk, &freq, optval, optlen, &err); 601 if (fl == NULL) 602 return err; 603 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 604 605 if (freq.flr_label) { 606 err = -EEXIST; 607 rcu_read_lock_bh(); 608 for_each_sk_fl_rcu(np, sfl) { 609 if (sfl->fl->label == freq.flr_label) { 610 if (freq.flr_flags&IPV6_FL_F_EXCL) { 611 rcu_read_unlock_bh(); 612 goto done; 613 } 614 fl1 = sfl->fl; 615 atomic_inc(&fl1->users); 616 break; 617 } 618 } 619 rcu_read_unlock_bh(); 620 621 if (fl1 == NULL) 622 fl1 = fl_lookup(net, freq.flr_label); 623 if (fl1) { 624 recheck: 625 err = -EEXIST; 626 if (freq.flr_flags&IPV6_FL_F_EXCL) 627 goto release; 628 err = -EPERM; 629 if (fl1->share == IPV6_FL_S_EXCL || 630 fl1->share != fl->share || 631 ((fl1->share == IPV6_FL_S_PROCESS) && 632 (fl1->owner.pid == fl->owner.pid)) || 633 ((fl1->share == IPV6_FL_S_USER) && 634 uid_eq(fl1->owner.uid, fl->owner.uid))) 635 goto release; 636 637 err = -ENOMEM; 638 if (sfl1 == NULL) 639 goto release; 640 if (fl->linger > fl1->linger) 641 fl1->linger = fl->linger; 642 if ((long)(fl->expires - fl1->expires) > 0) 643 fl1->expires = fl->expires; 644 fl_link(np, sfl1, fl1); 645 fl_free(fl); 646 return 0; 647 648 release: 649 fl_release(fl1); 650 goto done; 651 } 652 } 653 err = -ENOENT; 654 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 655 goto done; 656 657 err = -ENOMEM; 658 if (sfl1 == NULL || (err = mem_check(sk)) != 0) 659 goto done; 660 661 fl1 = fl_intern(net, fl, freq.flr_label); 662 if (fl1 != NULL) 663 goto recheck; 664 665 if (!freq.flr_label) { 666 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 667 &fl->label, sizeof(fl->label))) { 668 /* Intentionally ignore fault. */ 669 } 670 } 671 672 fl_link(np, sfl1, fl); 673 return 0; 674 675 default: 676 return -EINVAL; 677 } 678 679 done: 680 fl_free(fl); 681 kfree(sfl1); 682 return err; 683 } 684 685 #ifdef CONFIG_PROC_FS 686 687 struct ip6fl_iter_state { 688 struct seq_net_private p; 689 struct pid_namespace *pid_ns; 690 int bucket; 691 }; 692 693 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 694 695 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 696 { 697 struct ip6_flowlabel *fl = NULL; 698 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 699 struct net *net = seq_file_net(seq); 700 701 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 702 for_each_fl_rcu(state->bucket, fl) { 703 if (net_eq(fl->fl_net, net)) 704 goto out; 705 } 706 } 707 fl = NULL; 708 out: 709 return fl; 710 } 711 712 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 713 { 714 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 715 struct net *net = seq_file_net(seq); 716 717 for_each_fl_continue_rcu(fl) { 718 if (net_eq(fl->fl_net, net)) 719 goto out; 720 } 721 722 try_again: 723 if (++state->bucket <= FL_HASH_MASK) { 724 for_each_fl_rcu(state->bucket, fl) { 725 if (net_eq(fl->fl_net, net)) 726 goto out; 727 } 728 goto try_again; 729 } 730 fl = NULL; 731 732 out: 733 return fl; 734 } 735 736 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 737 { 738 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 739 if (fl) 740 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 741 --pos; 742 return pos ? NULL : fl; 743 } 744 745 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 746 __acquires(RCU) 747 { 748 rcu_read_lock_bh(); 749 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 750 } 751 752 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 753 { 754 struct ip6_flowlabel *fl; 755 756 if (v == SEQ_START_TOKEN) 757 fl = ip6fl_get_first(seq); 758 else 759 fl = ip6fl_get_next(seq, v); 760 ++*pos; 761 return fl; 762 } 763 764 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 765 __releases(RCU) 766 { 767 rcu_read_unlock_bh(); 768 } 769 770 static int ip6fl_seq_show(struct seq_file *seq, void *v) 771 { 772 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 773 if (v == SEQ_START_TOKEN) 774 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n", 775 "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt"); 776 else { 777 struct ip6_flowlabel *fl = v; 778 seq_printf(seq, 779 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 780 (unsigned int)ntohl(fl->label), 781 fl->share, 782 ((fl->share == IPV6_FL_S_PROCESS) ? 783 pid_nr_ns(fl->owner.pid, state->pid_ns) : 784 ((fl->share == IPV6_FL_S_USER) ? 785 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 786 0)), 787 atomic_read(&fl->users), 788 fl->linger/HZ, 789 (long)(fl->expires - jiffies)/HZ, 790 &fl->dst, 791 fl->opt ? fl->opt->opt_nflen : 0); 792 } 793 return 0; 794 } 795 796 static const struct seq_operations ip6fl_seq_ops = { 797 .start = ip6fl_seq_start, 798 .next = ip6fl_seq_next, 799 .stop = ip6fl_seq_stop, 800 .show = ip6fl_seq_show, 801 }; 802 803 static int ip6fl_seq_open(struct inode *inode, struct file *file) 804 { 805 struct seq_file *seq; 806 struct ip6fl_iter_state *state; 807 int err; 808 809 err = seq_open_net(inode, file, &ip6fl_seq_ops, 810 sizeof(struct ip6fl_iter_state)); 811 812 if (!err) { 813 seq = file->private_data; 814 state = ip6fl_seq_private(seq); 815 rcu_read_lock(); 816 state->pid_ns = get_pid_ns(task_active_pid_ns(current)); 817 rcu_read_unlock(); 818 } 819 return err; 820 } 821 822 static int ip6fl_seq_release(struct inode *inode, struct file *file) 823 { 824 struct seq_file *seq = file->private_data; 825 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 826 put_pid_ns(state->pid_ns); 827 return seq_release_net(inode, file); 828 } 829 830 static const struct file_operations ip6fl_seq_fops = { 831 .owner = THIS_MODULE, 832 .open = ip6fl_seq_open, 833 .read = seq_read, 834 .llseek = seq_lseek, 835 .release = ip6fl_seq_release, 836 }; 837 838 static int __net_init ip6_flowlabel_proc_init(struct net *net) 839 { 840 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net, 841 &ip6fl_seq_fops)) 842 return -ENOMEM; 843 return 0; 844 } 845 846 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 847 { 848 remove_proc_entry("ip6_flowlabel", net->proc_net); 849 } 850 #else 851 static inline int ip6_flowlabel_proc_init(struct net *net) 852 { 853 return 0; 854 } 855 static inline void ip6_flowlabel_proc_fini(struct net *net) 856 { 857 } 858 #endif 859 860 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 861 { 862 ip6_fl_purge(net); 863 ip6_flowlabel_proc_fini(net); 864 } 865 866 static struct pernet_operations ip6_flowlabel_net_ops = { 867 .init = ip6_flowlabel_proc_init, 868 .exit = ip6_flowlabel_net_exit, 869 }; 870 871 int ip6_flowlabel_init(void) 872 { 873 return register_pernet_subsys(&ip6_flowlabel_net_ops); 874 } 875 876 void ip6_flowlabel_cleanup(void) 877 { 878 del_timer(&ip6_fl_gc_timer); 879 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 880 } 881