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 kfree(fl->opt); 104 kfree_rcu(fl, rcu); 105 } 106 } 107 108 static void fl_release(struct ip6_flowlabel *fl) 109 { 110 spin_lock_bh(&ip6_fl_lock); 111 112 fl->lastuse = jiffies; 113 if (atomic_dec_and_test(&fl->users)) { 114 unsigned long ttd = fl->lastuse + fl->linger; 115 if (time_after(ttd, fl->expires)) 116 fl->expires = ttd; 117 ttd = fl->expires; 118 if (fl->opt && fl->share == IPV6_FL_S_EXCL) { 119 struct ipv6_txoptions *opt = fl->opt; 120 fl->opt = NULL; 121 kfree(opt); 122 } 123 if (!timer_pending(&ip6_fl_gc_timer) || 124 time_after(ip6_fl_gc_timer.expires, ttd)) 125 mod_timer(&ip6_fl_gc_timer, ttd); 126 } 127 spin_unlock_bh(&ip6_fl_lock); 128 } 129 130 static void ip6_fl_gc(unsigned long dummy) 131 { 132 int i; 133 unsigned long now = jiffies; 134 unsigned long sched = 0; 135 136 spin_lock(&ip6_fl_lock); 137 138 for (i = 0; i <= FL_HASH_MASK; i++) { 139 struct ip6_flowlabel *fl; 140 struct ip6_flowlabel __rcu **flp; 141 142 flp = &fl_ht[i]; 143 while ((fl = rcu_dereference_protected(*flp, 144 lockdep_is_held(&ip6_fl_lock))) != NULL) { 145 if (atomic_read(&fl->users) == 0) { 146 unsigned long ttd = fl->lastuse + fl->linger; 147 if (time_after(ttd, fl->expires)) 148 fl->expires = ttd; 149 ttd = fl->expires; 150 if (time_after_eq(now, ttd)) { 151 *flp = fl->next; 152 fl_free(fl); 153 atomic_dec(&fl_size); 154 continue; 155 } 156 if (!sched || time_before(ttd, sched)) 157 sched = ttd; 158 } 159 flp = &fl->next; 160 } 161 } 162 if (!sched && atomic_read(&fl_size)) 163 sched = now + FL_MAX_LINGER; 164 if (sched) { 165 mod_timer(&ip6_fl_gc_timer, sched); 166 } 167 spin_unlock(&ip6_fl_lock); 168 } 169 170 static void __net_exit ip6_fl_purge(struct net *net) 171 { 172 int i; 173 174 spin_lock_bh(&ip6_fl_lock); 175 for (i = 0; i <= FL_HASH_MASK; i++) { 176 struct ip6_flowlabel *fl; 177 struct ip6_flowlabel __rcu **flp; 178 179 flp = &fl_ht[i]; 180 while ((fl = rcu_dereference_protected(*flp, 181 lockdep_is_held(&ip6_fl_lock))) != NULL) { 182 if (net_eq(fl->fl_net, net) && 183 atomic_read(&fl->users) == 0) { 184 *flp = fl->next; 185 fl_free(fl); 186 atomic_dec(&fl_size); 187 continue; 188 } 189 flp = &fl->next; 190 } 191 } 192 spin_unlock_bh(&ip6_fl_lock); 193 } 194 195 static struct ip6_flowlabel *fl_intern(struct net *net, 196 struct ip6_flowlabel *fl, __be32 label) 197 { 198 struct ip6_flowlabel *lfl; 199 200 fl->label = label & IPV6_FLOWLABEL_MASK; 201 202 spin_lock_bh(&ip6_fl_lock); 203 if (label == 0) { 204 for (;;) { 205 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK; 206 if (fl->label) { 207 lfl = __fl_lookup(net, fl->label); 208 if (!lfl) 209 break; 210 } 211 } 212 } else { 213 /* 214 * we dropper the ip6_fl_lock, so this entry could reappear 215 * and we need to recheck with it. 216 * 217 * OTOH no need to search the active socket first, like it is 218 * done in ipv6_flowlabel_opt - sock is locked, so new entry 219 * with the same label can only appear on another sock 220 */ 221 lfl = __fl_lookup(net, fl->label); 222 if (lfl) { 223 atomic_inc(&lfl->users); 224 spin_unlock_bh(&ip6_fl_lock); 225 return lfl; 226 } 227 } 228 229 fl->lastuse = jiffies; 230 fl->next = fl_ht[FL_HASH(fl->label)]; 231 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 232 atomic_inc(&fl_size); 233 spin_unlock_bh(&ip6_fl_lock); 234 return NULL; 235 } 236 237 238 239 /* Socket flowlabel lists */ 240 241 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label) 242 { 243 struct ipv6_fl_socklist *sfl; 244 struct ipv6_pinfo *np = inet6_sk(sk); 245 246 label &= IPV6_FLOWLABEL_MASK; 247 248 rcu_read_lock_bh(); 249 for_each_sk_fl_rcu(np, sfl) { 250 struct ip6_flowlabel *fl = sfl->fl; 251 if (fl->label == label) { 252 fl->lastuse = jiffies; 253 atomic_inc(&fl->users); 254 rcu_read_unlock_bh(); 255 return fl; 256 } 257 } 258 rcu_read_unlock_bh(); 259 return NULL; 260 } 261 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 262 263 void fl6_free_socklist(struct sock *sk) 264 { 265 struct ipv6_pinfo *np = inet6_sk(sk); 266 struct ipv6_fl_socklist *sfl; 267 268 if (!rcu_access_pointer(np->ipv6_fl_list)) 269 return; 270 271 spin_lock_bh(&ip6_sk_fl_lock); 272 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 273 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 274 np->ipv6_fl_list = sfl->next; 275 spin_unlock_bh(&ip6_sk_fl_lock); 276 277 fl_release(sfl->fl); 278 kfree_rcu(sfl, rcu); 279 280 spin_lock_bh(&ip6_sk_fl_lock); 281 } 282 spin_unlock_bh(&ip6_sk_fl_lock); 283 } 284 285 /* Service routines */ 286 287 288 /* 289 It is the only difficult place. flowlabel enforces equal headers 290 before and including routing header, however user may supply options 291 following rthdr. 292 */ 293 294 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 295 struct ip6_flowlabel *fl, 296 struct ipv6_txoptions *fopt) 297 { 298 struct ipv6_txoptions *fl_opt = fl->opt; 299 300 if (!fopt || fopt->opt_flen == 0) 301 return fl_opt; 302 303 if (fl_opt) { 304 opt_space->hopopt = fl_opt->hopopt; 305 opt_space->dst0opt = fl_opt->dst0opt; 306 opt_space->srcrt = fl_opt->srcrt; 307 opt_space->opt_nflen = fl_opt->opt_nflen; 308 } else { 309 if (fopt->opt_nflen == 0) 310 return fopt; 311 opt_space->hopopt = NULL; 312 opt_space->dst0opt = NULL; 313 opt_space->srcrt = NULL; 314 opt_space->opt_nflen = 0; 315 } 316 opt_space->dst1opt = fopt->dst1opt; 317 opt_space->opt_flen = fopt->opt_flen; 318 return opt_space; 319 } 320 EXPORT_SYMBOL_GPL(fl6_merge_options); 321 322 static unsigned long check_linger(unsigned long ttl) 323 { 324 if (ttl < FL_MIN_LINGER) 325 return FL_MIN_LINGER*HZ; 326 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 327 return 0; 328 return ttl*HZ; 329 } 330 331 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 332 { 333 linger = check_linger(linger); 334 if (!linger) 335 return -EPERM; 336 expires = check_linger(expires); 337 if (!expires) 338 return -EPERM; 339 340 spin_lock_bh(&ip6_fl_lock); 341 fl->lastuse = jiffies; 342 if (time_before(fl->linger, linger)) 343 fl->linger = linger; 344 if (time_before(expires, fl->linger)) 345 expires = fl->linger; 346 if (time_before(fl->expires, fl->lastuse + expires)) 347 fl->expires = fl->lastuse + expires; 348 spin_unlock_bh(&ip6_fl_lock); 349 350 return 0; 351 } 352 353 static struct ip6_flowlabel * 354 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 355 char __user *optval, int optlen, int *err_p) 356 { 357 struct ip6_flowlabel *fl = NULL; 358 int olen; 359 int addr_type; 360 int err; 361 362 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 363 err = -EINVAL; 364 if (olen > 64 * 1024) 365 goto done; 366 367 err = -ENOMEM; 368 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 369 if (!fl) 370 goto done; 371 372 if (olen > 0) { 373 struct msghdr msg; 374 struct flowi6 flowi6; 375 struct sockcm_cookie sockc_junk; 376 struct ipcm6_cookie ipc6; 377 378 err = -ENOMEM; 379 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 380 if (!fl->opt) 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 ipc6.opt = fl->opt; 394 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6, &sockc_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 = 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_protected(*sflp, 545 lockdep_is_held(&ip6_sk_fl_lock))) != 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 = 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 if (net->ipv6.sysctl.flowlabel_state_ranges && 601 (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 602 return -ERANGE; 603 604 fl = fl_create(net, sk, &freq, optval, optlen, &err); 605 if (!fl) 606 return err; 607 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 608 609 if (freq.flr_label) { 610 err = -EEXIST; 611 rcu_read_lock_bh(); 612 for_each_sk_fl_rcu(np, sfl) { 613 if (sfl->fl->label == freq.flr_label) { 614 if (freq.flr_flags&IPV6_FL_F_EXCL) { 615 rcu_read_unlock_bh(); 616 goto done; 617 } 618 fl1 = sfl->fl; 619 atomic_inc(&fl1->users); 620 break; 621 } 622 } 623 rcu_read_unlock_bh(); 624 625 if (!fl1) 626 fl1 = fl_lookup(net, freq.flr_label); 627 if (fl1) { 628 recheck: 629 err = -EEXIST; 630 if (freq.flr_flags&IPV6_FL_F_EXCL) 631 goto release; 632 err = -EPERM; 633 if (fl1->share == IPV6_FL_S_EXCL || 634 fl1->share != fl->share || 635 ((fl1->share == IPV6_FL_S_PROCESS) && 636 (fl1->owner.pid == fl->owner.pid)) || 637 ((fl1->share == IPV6_FL_S_USER) && 638 uid_eq(fl1->owner.uid, fl->owner.uid))) 639 goto release; 640 641 err = -ENOMEM; 642 if (!sfl1) 643 goto release; 644 if (fl->linger > fl1->linger) 645 fl1->linger = fl->linger; 646 if ((long)(fl->expires - fl1->expires) > 0) 647 fl1->expires = fl->expires; 648 fl_link(np, sfl1, fl1); 649 fl_free(fl); 650 return 0; 651 652 release: 653 fl_release(fl1); 654 goto done; 655 } 656 } 657 err = -ENOENT; 658 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 659 goto done; 660 661 err = -ENOMEM; 662 if (!sfl1) 663 goto done; 664 665 err = mem_check(sk); 666 if (err != 0) 667 goto done; 668 669 fl1 = fl_intern(net, fl, freq.flr_label); 670 if (fl1) 671 goto recheck; 672 673 if (!freq.flr_label) { 674 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 675 &fl->label, sizeof(fl->label))) { 676 /* Intentionally ignore fault. */ 677 } 678 } 679 680 fl_link(np, sfl1, fl); 681 return 0; 682 683 default: 684 return -EINVAL; 685 } 686 687 done: 688 fl_free(fl); 689 kfree(sfl1); 690 return err; 691 } 692 693 #ifdef CONFIG_PROC_FS 694 695 struct ip6fl_iter_state { 696 struct seq_net_private p; 697 struct pid_namespace *pid_ns; 698 int bucket; 699 }; 700 701 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 702 703 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 704 { 705 struct ip6_flowlabel *fl = NULL; 706 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 707 struct net *net = seq_file_net(seq); 708 709 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 710 for_each_fl_rcu(state->bucket, fl) { 711 if (net_eq(fl->fl_net, net)) 712 goto out; 713 } 714 } 715 fl = NULL; 716 out: 717 return fl; 718 } 719 720 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 721 { 722 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 723 struct net *net = seq_file_net(seq); 724 725 for_each_fl_continue_rcu(fl) { 726 if (net_eq(fl->fl_net, net)) 727 goto out; 728 } 729 730 try_again: 731 if (++state->bucket <= FL_HASH_MASK) { 732 for_each_fl_rcu(state->bucket, fl) { 733 if (net_eq(fl->fl_net, net)) 734 goto out; 735 } 736 goto try_again; 737 } 738 fl = NULL; 739 740 out: 741 return fl; 742 } 743 744 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 745 { 746 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 747 if (fl) 748 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 749 --pos; 750 return pos ? NULL : fl; 751 } 752 753 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 754 __acquires(RCU) 755 { 756 rcu_read_lock_bh(); 757 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 758 } 759 760 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 761 { 762 struct ip6_flowlabel *fl; 763 764 if (v == SEQ_START_TOKEN) 765 fl = ip6fl_get_first(seq); 766 else 767 fl = ip6fl_get_next(seq, v); 768 ++*pos; 769 return fl; 770 } 771 772 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 773 __releases(RCU) 774 { 775 rcu_read_unlock_bh(); 776 } 777 778 static int ip6fl_seq_show(struct seq_file *seq, void *v) 779 { 780 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 781 if (v == SEQ_START_TOKEN) { 782 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 783 } else { 784 struct ip6_flowlabel *fl = v; 785 seq_printf(seq, 786 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 787 (unsigned int)ntohl(fl->label), 788 fl->share, 789 ((fl->share == IPV6_FL_S_PROCESS) ? 790 pid_nr_ns(fl->owner.pid, state->pid_ns) : 791 ((fl->share == IPV6_FL_S_USER) ? 792 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 793 0)), 794 atomic_read(&fl->users), 795 fl->linger/HZ, 796 (long)(fl->expires - jiffies)/HZ, 797 &fl->dst, 798 fl->opt ? fl->opt->opt_nflen : 0); 799 } 800 return 0; 801 } 802 803 static const struct seq_operations ip6fl_seq_ops = { 804 .start = ip6fl_seq_start, 805 .next = ip6fl_seq_next, 806 .stop = ip6fl_seq_stop, 807 .show = ip6fl_seq_show, 808 }; 809 810 static int ip6fl_seq_open(struct inode *inode, struct file *file) 811 { 812 struct seq_file *seq; 813 struct ip6fl_iter_state *state; 814 int err; 815 816 err = seq_open_net(inode, file, &ip6fl_seq_ops, 817 sizeof(struct ip6fl_iter_state)); 818 819 if (!err) { 820 seq = file->private_data; 821 state = ip6fl_seq_private(seq); 822 rcu_read_lock(); 823 state->pid_ns = get_pid_ns(task_active_pid_ns(current)); 824 rcu_read_unlock(); 825 } 826 return err; 827 } 828 829 static int ip6fl_seq_release(struct inode *inode, struct file *file) 830 { 831 struct seq_file *seq = file->private_data; 832 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 833 put_pid_ns(state->pid_ns); 834 return seq_release_net(inode, file); 835 } 836 837 static const struct file_operations ip6fl_seq_fops = { 838 .owner = THIS_MODULE, 839 .open = ip6fl_seq_open, 840 .read = seq_read, 841 .llseek = seq_lseek, 842 .release = ip6fl_seq_release, 843 }; 844 845 static int __net_init ip6_flowlabel_proc_init(struct net *net) 846 { 847 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net, 848 &ip6fl_seq_fops)) 849 return -ENOMEM; 850 return 0; 851 } 852 853 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 854 { 855 remove_proc_entry("ip6_flowlabel", net->proc_net); 856 } 857 #else 858 static inline int ip6_flowlabel_proc_init(struct net *net) 859 { 860 return 0; 861 } 862 static inline void ip6_flowlabel_proc_fini(struct net *net) 863 { 864 } 865 #endif 866 867 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 868 { 869 ip6_fl_purge(net); 870 ip6_flowlabel_proc_fini(net); 871 } 872 873 static struct pernet_operations ip6_flowlabel_net_ops = { 874 .init = ip6_flowlabel_proc_init, 875 .exit = ip6_flowlabel_net_exit, 876 }; 877 878 int ip6_flowlabel_init(void) 879 { 880 return register_pernet_subsys(&ip6_flowlabel_net_ops); 881 } 882 883 void ip6_flowlabel_cleanup(void) 884 { 885 del_timer(&ip6_fl_gc_timer); 886 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 887 } 888