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/if_arp.h> 19 #include <linux/in6.h> 20 #include <linux/route.h> 21 #include <linux/proc_fs.h> 22 #include <linux/seq_file.h> 23 #include <linux/slab.h> 24 #include <linux/export.h> 25 #include <linux/pid_namespace.h> 26 27 #include <net/net_namespace.h> 28 #include <net/sock.h> 29 30 #include <net/ipv6.h> 31 #include <net/ndisc.h> 32 #include <net/protocol.h> 33 #include <net/ip6_route.h> 34 #include <net/addrconf.h> 35 #include <net/rawv6.h> 36 #include <net/icmp.h> 37 #include <net/transp_v6.h> 38 39 #include <asm/uaccess.h> 40 41 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified 42 in old IPv6 RFC. Well, it was reasonable value. 43 */ 44 #define FL_MAX_LINGER 60 /* Maximal linger timeout */ 45 46 /* FL hash table */ 47 48 #define FL_MAX_PER_SOCK 32 49 #define FL_MAX_SIZE 4096 50 #define FL_HASH_MASK 255 51 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK) 52 53 static atomic_t fl_size = ATOMIC_INIT(0); 54 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1]; 55 56 static void ip6_fl_gc(unsigned long dummy); 57 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0); 58 59 /* FL hash table lock: it protects only of GC */ 60 61 static DEFINE_SPINLOCK(ip6_fl_lock); 62 63 /* Big socket sock */ 64 65 static DEFINE_SPINLOCK(ip6_sk_fl_lock); 66 67 #define for_each_fl_rcu(hash, fl) \ 68 for (fl = rcu_dereference_bh(fl_ht[(hash)]); \ 69 fl != NULL; \ 70 fl = rcu_dereference_bh(fl->next)) 71 #define for_each_fl_continue_rcu(fl) \ 72 for (fl = rcu_dereference_bh(fl->next); \ 73 fl != NULL; \ 74 fl = rcu_dereference_bh(fl->next)) 75 76 #define for_each_sk_fl_rcu(np, sfl) \ 77 for (sfl = rcu_dereference_bh(np->ipv6_fl_list); \ 78 sfl != NULL; \ 79 sfl = rcu_dereference_bh(sfl->next)) 80 81 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label) 82 { 83 struct ip6_flowlabel *fl; 84 85 for_each_fl_rcu(FL_HASH(label), fl) { 86 if (fl->label == label && net_eq(fl->fl_net, net)) 87 return fl; 88 } 89 return NULL; 90 } 91 92 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) 93 { 94 struct ip6_flowlabel *fl; 95 96 rcu_read_lock_bh(); 97 fl = __fl_lookup(net, label); 98 if (fl && !atomic_inc_not_zero(&fl->users)) 99 fl = NULL; 100 rcu_read_unlock_bh(); 101 return fl; 102 } 103 104 105 static void fl_free(struct ip6_flowlabel *fl) 106 { 107 if (fl) { 108 if (fl->share == IPV6_FL_S_PROCESS) 109 put_pid(fl->owner.pid); 110 release_net(fl->fl_net); 111 kfree(fl->opt); 112 kfree_rcu(fl, rcu); 113 } 114 } 115 116 static void fl_release(struct ip6_flowlabel *fl) 117 { 118 spin_lock_bh(&ip6_fl_lock); 119 120 fl->lastuse = jiffies; 121 if (atomic_dec_and_test(&fl->users)) { 122 unsigned long ttd = fl->lastuse + fl->linger; 123 if (time_after(ttd, fl->expires)) 124 fl->expires = ttd; 125 ttd = fl->expires; 126 if (fl->opt && fl->share == IPV6_FL_S_EXCL) { 127 struct ipv6_txoptions *opt = fl->opt; 128 fl->opt = NULL; 129 kfree(opt); 130 } 131 if (!timer_pending(&ip6_fl_gc_timer) || 132 time_after(ip6_fl_gc_timer.expires, ttd)) 133 mod_timer(&ip6_fl_gc_timer, ttd); 134 } 135 spin_unlock_bh(&ip6_fl_lock); 136 } 137 138 static void ip6_fl_gc(unsigned long dummy) 139 { 140 int i; 141 unsigned long now = jiffies; 142 unsigned long sched = 0; 143 144 spin_lock(&ip6_fl_lock); 145 146 for (i=0; i<=FL_HASH_MASK; i++) { 147 struct ip6_flowlabel *fl, **flp; 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(&ip6_fl_lock); 181 for (i = 0; i <= FL_HASH_MASK; i++) { 182 struct ip6_flowlabel *fl, **flp; 183 flp = &fl_ht[i]; 184 while ((fl = rcu_dereference_protected(*flp, 185 lockdep_is_held(&ip6_fl_lock))) != NULL) { 186 if (net_eq(fl->fl_net, net) && 187 atomic_read(&fl->users) == 0) { 188 *flp = fl->next; 189 fl_free(fl); 190 atomic_dec(&fl_size); 191 continue; 192 } 193 flp = &fl->next; 194 } 195 } 196 spin_unlock(&ip6_fl_lock); 197 } 198 199 static struct ip6_flowlabel *fl_intern(struct net *net, 200 struct ip6_flowlabel *fl, __be32 label) 201 { 202 struct ip6_flowlabel *lfl; 203 204 fl->label = label & IPV6_FLOWLABEL_MASK; 205 206 spin_lock_bh(&ip6_fl_lock); 207 if (label == 0) { 208 for (;;) { 209 fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK; 210 if (fl->label) { 211 lfl = __fl_lookup(net, fl->label); 212 if (lfl == NULL) 213 break; 214 } 215 } 216 } else { 217 /* 218 * we dropper the ip6_fl_lock, so this entry could reappear 219 * and we need to recheck with it. 220 * 221 * OTOH no need to search the active socket first, like it is 222 * done in ipv6_flowlabel_opt - sock is locked, so new entry 223 * with the same label can only appear on another sock 224 */ 225 lfl = __fl_lookup(net, fl->label); 226 if (lfl != NULL) { 227 atomic_inc(&lfl->users); 228 spin_unlock_bh(&ip6_fl_lock); 229 return lfl; 230 } 231 } 232 233 fl->lastuse = jiffies; 234 fl->next = fl_ht[FL_HASH(fl->label)]; 235 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 236 atomic_inc(&fl_size); 237 spin_unlock_bh(&ip6_fl_lock); 238 return NULL; 239 } 240 241 242 243 /* Socket flowlabel lists */ 244 245 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label) 246 { 247 struct ipv6_fl_socklist *sfl; 248 struct ipv6_pinfo *np = inet6_sk(sk); 249 250 label &= IPV6_FLOWLABEL_MASK; 251 252 rcu_read_lock_bh(); 253 for_each_sk_fl_rcu(np, sfl) { 254 struct ip6_flowlabel *fl = sfl->fl; 255 if (fl->label == label) { 256 fl->lastuse = jiffies; 257 atomic_inc(&fl->users); 258 rcu_read_unlock_bh(); 259 return fl; 260 } 261 } 262 rcu_read_unlock_bh(); 263 return NULL; 264 } 265 266 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 267 268 void fl6_free_socklist(struct sock *sk) 269 { 270 struct ipv6_pinfo *np = inet6_sk(sk); 271 struct ipv6_fl_socklist *sfl; 272 273 if (!rcu_access_pointer(np->ipv6_fl_list)) 274 return; 275 276 spin_lock_bh(&ip6_sk_fl_lock); 277 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 278 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 279 np->ipv6_fl_list = sfl->next; 280 spin_unlock_bh(&ip6_sk_fl_lock); 281 282 fl_release(sfl->fl); 283 kfree_rcu(sfl, rcu); 284 285 spin_lock_bh(&ip6_sk_fl_lock); 286 } 287 spin_unlock_bh(&ip6_sk_fl_lock); 288 } 289 290 /* Service routines */ 291 292 293 /* 294 It is the only difficult place. flowlabel enforces equal headers 295 before and including routing header, however user may supply options 296 following rthdr. 297 */ 298 299 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space, 300 struct ip6_flowlabel * fl, 301 struct ipv6_txoptions * fopt) 302 { 303 struct ipv6_txoptions * fl_opt = fl->opt; 304 305 if (fopt == NULL || fopt->opt_flen == 0) 306 return fl_opt; 307 308 if (fl_opt != NULL) { 309 opt_space->hopopt = fl_opt->hopopt; 310 opt_space->dst0opt = fl_opt->dst0opt; 311 opt_space->srcrt = fl_opt->srcrt; 312 opt_space->opt_nflen = fl_opt->opt_nflen; 313 } else { 314 if (fopt->opt_nflen == 0) 315 return fopt; 316 opt_space->hopopt = NULL; 317 opt_space->dst0opt = NULL; 318 opt_space->srcrt = NULL; 319 opt_space->opt_nflen = 0; 320 } 321 opt_space->dst1opt = fopt->dst1opt; 322 opt_space->opt_flen = fopt->opt_flen; 323 return opt_space; 324 } 325 EXPORT_SYMBOL_GPL(fl6_merge_options); 326 327 static unsigned long check_linger(unsigned long ttl) 328 { 329 if (ttl < FL_MIN_LINGER) 330 return FL_MIN_LINGER*HZ; 331 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 332 return 0; 333 return ttl*HZ; 334 } 335 336 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 337 { 338 linger = check_linger(linger); 339 if (!linger) 340 return -EPERM; 341 expires = check_linger(expires); 342 if (!expires) 343 return -EPERM; 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 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 for_each_sk_fl_rcu(np, sfl) 453 count++; 454 455 if (room <= 0 || 456 ((count >= FL_MAX_PER_SOCK || 457 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 458 !capable(CAP_NET_ADMIN))) 459 return -ENOBUFS; 460 461 return 0; 462 } 463 464 static bool ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2) 465 { 466 if (h1 == h2) 467 return false; 468 if (h1 == NULL || h2 == NULL) 469 return true; 470 if (h1->hdrlen != h2->hdrlen) 471 return true; 472 return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1)); 473 } 474 475 static bool ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2) 476 { 477 if (o1 == o2) 478 return false; 479 if (o1 == NULL || o2 == NULL) 480 return true; 481 if (o1->opt_nflen != o2->opt_nflen) 482 return true; 483 if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt)) 484 return true; 485 if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt)) 486 return true; 487 if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt)) 488 return true; 489 return false; 490 } 491 492 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 493 struct ip6_flowlabel *fl) 494 { 495 spin_lock_bh(&ip6_sk_fl_lock); 496 sfl->fl = fl; 497 sfl->next = np->ipv6_fl_list; 498 rcu_assign_pointer(np->ipv6_fl_list, sfl); 499 spin_unlock_bh(&ip6_sk_fl_lock); 500 } 501 502 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen) 503 { 504 int uninitialized_var(err); 505 struct net *net = sock_net(sk); 506 struct ipv6_pinfo *np = inet6_sk(sk); 507 struct in6_flowlabel_req freq; 508 struct ipv6_fl_socklist *sfl1=NULL; 509 struct ipv6_fl_socklist *sfl, **sflp; 510 struct ip6_flowlabel *fl, *fl1 = NULL; 511 512 513 if (optlen < sizeof(freq)) 514 return -EINVAL; 515 516 if (copy_from_user(&freq, optval, sizeof(freq))) 517 return -EFAULT; 518 519 switch (freq.flr_action) { 520 case IPV6_FL_A_PUT: 521 spin_lock_bh(&ip6_sk_fl_lock); 522 for (sflp = &np->ipv6_fl_list; 523 (sfl = rcu_dereference(*sflp))!=NULL; 524 sflp = &sfl->next) { 525 if (sfl->fl->label == freq.flr_label) { 526 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK)) 527 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 528 *sflp = rcu_dereference(sfl->next); 529 spin_unlock_bh(&ip6_sk_fl_lock); 530 fl_release(sfl->fl); 531 kfree_rcu(sfl, rcu); 532 return 0; 533 } 534 } 535 spin_unlock_bh(&ip6_sk_fl_lock); 536 return -ESRCH; 537 538 case IPV6_FL_A_RENEW: 539 rcu_read_lock_bh(); 540 for_each_sk_fl_rcu(np, sfl) { 541 if (sfl->fl->label == freq.flr_label) { 542 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires); 543 rcu_read_unlock_bh(); 544 return err; 545 } 546 } 547 rcu_read_unlock_bh(); 548 549 if (freq.flr_share == IPV6_FL_S_NONE && 550 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 551 fl = fl_lookup(net, freq.flr_label); 552 if (fl) { 553 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires); 554 fl_release(fl); 555 return err; 556 } 557 } 558 return -ESRCH; 559 560 case IPV6_FL_A_GET: 561 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK) 562 return -EINVAL; 563 564 fl = fl_create(net, sk, &freq, optval, optlen, &err); 565 if (fl == NULL) 566 return err; 567 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 568 569 if (freq.flr_label) { 570 err = -EEXIST; 571 rcu_read_lock_bh(); 572 for_each_sk_fl_rcu(np, sfl) { 573 if (sfl->fl->label == freq.flr_label) { 574 if (freq.flr_flags&IPV6_FL_F_EXCL) { 575 rcu_read_unlock_bh(); 576 goto done; 577 } 578 fl1 = sfl->fl; 579 atomic_inc(&fl1->users); 580 break; 581 } 582 } 583 rcu_read_unlock_bh(); 584 585 if (fl1 == NULL) 586 fl1 = fl_lookup(net, freq.flr_label); 587 if (fl1) { 588 recheck: 589 err = -EEXIST; 590 if (freq.flr_flags&IPV6_FL_F_EXCL) 591 goto release; 592 err = -EPERM; 593 if (fl1->share == IPV6_FL_S_EXCL || 594 fl1->share != fl->share || 595 ((fl1->share == IPV6_FL_S_PROCESS) && 596 (fl1->owner.pid == fl->owner.pid)) || 597 ((fl1->share == IPV6_FL_S_USER) && 598 uid_eq(fl1->owner.uid, fl->owner.uid))) 599 goto release; 600 601 err = -EINVAL; 602 if (!ipv6_addr_equal(&fl1->dst, &fl->dst) || 603 ipv6_opt_cmp(fl1->opt, fl->opt)) 604 goto release; 605 606 err = -ENOMEM; 607 if (sfl1 == NULL) 608 goto release; 609 if (fl->linger > fl1->linger) 610 fl1->linger = fl->linger; 611 if ((long)(fl->expires - fl1->expires) > 0) 612 fl1->expires = fl->expires; 613 fl_link(np, sfl1, fl1); 614 fl_free(fl); 615 return 0; 616 617 release: 618 fl_release(fl1); 619 goto done; 620 } 621 } 622 err = -ENOENT; 623 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 624 goto done; 625 626 err = -ENOMEM; 627 if (sfl1 == NULL || (err = mem_check(sk)) != 0) 628 goto done; 629 630 fl1 = fl_intern(net, fl, freq.flr_label); 631 if (fl1 != NULL) 632 goto recheck; 633 634 if (!freq.flr_label) { 635 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 636 &fl->label, sizeof(fl->label))) { 637 /* Intentionally ignore fault. */ 638 } 639 } 640 641 fl_link(np, sfl1, fl); 642 return 0; 643 644 default: 645 return -EINVAL; 646 } 647 648 done: 649 fl_free(fl); 650 kfree(sfl1); 651 return err; 652 } 653 654 #ifdef CONFIG_PROC_FS 655 656 struct ip6fl_iter_state { 657 struct seq_net_private p; 658 struct pid_namespace *pid_ns; 659 int bucket; 660 }; 661 662 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 663 664 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 665 { 666 struct ip6_flowlabel *fl = NULL; 667 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 668 struct net *net = seq_file_net(seq); 669 670 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 671 for_each_fl_rcu(state->bucket, fl) { 672 if (net_eq(fl->fl_net, net)) 673 goto out; 674 } 675 } 676 fl = NULL; 677 out: 678 return fl; 679 } 680 681 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 682 { 683 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 684 struct net *net = seq_file_net(seq); 685 686 for_each_fl_continue_rcu(fl) { 687 if (net_eq(fl->fl_net, net)) 688 goto out; 689 } 690 691 try_again: 692 if (++state->bucket <= FL_HASH_MASK) { 693 for_each_fl_rcu(state->bucket, fl) { 694 if (net_eq(fl->fl_net, net)) 695 goto out; 696 } 697 goto try_again; 698 } 699 fl = NULL; 700 701 out: 702 return fl; 703 } 704 705 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 706 { 707 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 708 if (fl) 709 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 710 --pos; 711 return pos ? NULL : fl; 712 } 713 714 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 715 __acquires(RCU) 716 { 717 rcu_read_lock_bh(); 718 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 719 } 720 721 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 722 { 723 struct ip6_flowlabel *fl; 724 725 if (v == SEQ_START_TOKEN) 726 fl = ip6fl_get_first(seq); 727 else 728 fl = ip6fl_get_next(seq, v); 729 ++*pos; 730 return fl; 731 } 732 733 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 734 __releases(RCU) 735 { 736 rcu_read_unlock_bh(); 737 } 738 739 static int ip6fl_seq_show(struct seq_file *seq, void *v) 740 { 741 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 742 if (v == SEQ_START_TOKEN) 743 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n", 744 "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt"); 745 else { 746 struct ip6_flowlabel *fl = v; 747 seq_printf(seq, 748 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 749 (unsigned int)ntohl(fl->label), 750 fl->share, 751 ((fl->share == IPV6_FL_S_PROCESS) ? 752 pid_nr_ns(fl->owner.pid, state->pid_ns) : 753 ((fl->share == IPV6_FL_S_USER) ? 754 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 755 0)), 756 atomic_read(&fl->users), 757 fl->linger/HZ, 758 (long)(fl->expires - jiffies)/HZ, 759 &fl->dst, 760 fl->opt ? fl->opt->opt_nflen : 0); 761 } 762 return 0; 763 } 764 765 static const struct seq_operations ip6fl_seq_ops = { 766 .start = ip6fl_seq_start, 767 .next = ip6fl_seq_next, 768 .stop = ip6fl_seq_stop, 769 .show = ip6fl_seq_show, 770 }; 771 772 static int ip6fl_seq_open(struct inode *inode, struct file *file) 773 { 774 struct seq_file *seq; 775 struct ip6fl_iter_state *state; 776 int err; 777 778 err = seq_open_net(inode, file, &ip6fl_seq_ops, 779 sizeof(struct ip6fl_iter_state)); 780 781 if (!err) { 782 seq = file->private_data; 783 state = ip6fl_seq_private(seq); 784 rcu_read_lock(); 785 state->pid_ns = get_pid_ns(task_active_pid_ns(current)); 786 rcu_read_unlock(); 787 } 788 return err; 789 } 790 791 static int ip6fl_seq_release(struct inode *inode, struct file *file) 792 { 793 struct seq_file *seq = file->private_data; 794 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 795 put_pid_ns(state->pid_ns); 796 return seq_release_net(inode, file); 797 } 798 799 static const struct file_operations ip6fl_seq_fops = { 800 .owner = THIS_MODULE, 801 .open = ip6fl_seq_open, 802 .read = seq_read, 803 .llseek = seq_lseek, 804 .release = ip6fl_seq_release, 805 }; 806 807 static int __net_init ip6_flowlabel_proc_init(struct net *net) 808 { 809 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net, 810 &ip6fl_seq_fops)) 811 return -ENOMEM; 812 return 0; 813 } 814 815 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 816 { 817 remove_proc_entry("ip6_flowlabel", net->proc_net); 818 } 819 #else 820 static inline int ip6_flowlabel_proc_init(struct net *net) 821 { 822 return 0; 823 } 824 static inline void ip6_flowlabel_proc_fini(struct net *net) 825 { 826 } 827 #endif 828 829 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 830 { 831 ip6_fl_purge(net); 832 ip6_flowlabel_proc_fini(net); 833 } 834 835 static struct pernet_operations ip6_flowlabel_net_ops = { 836 .init = ip6_flowlabel_proc_init, 837 .exit = ip6_flowlabel_net_exit, 838 }; 839 840 int ip6_flowlabel_init(void) 841 { 842 return register_pernet_subsys(&ip6_flowlabel_net_ops); 843 } 844 845 void ip6_flowlabel_cleanup(void) 846 { 847 del_timer(&ip6_fl_gc_timer); 848 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 849 } 850