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 150 /* 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; 148 struct ip6_flowlabel __rcu **flp; 149 150 flp = &fl_ht[i]; 151 while ((fl = rcu_dereference_protected(*flp, 152 lockdep_is_held(&ip6_fl_lock))) != NULL) { 153 if (atomic_read(&fl->users) == 0) { 154 unsigned long ttd = fl->lastuse + fl->linger; 155 if (time_after(ttd, fl->expires)) 156 fl->expires = ttd; 157 ttd = fl->expires; 158 if (time_after_eq(now, ttd)) { 159 *flp = fl->next; 160 fl_free(fl); 161 atomic_dec(&fl_size); 162 continue; 163 } 164 if (!sched || time_before(ttd, sched)) 165 sched = ttd; 166 } 167 flp = &fl->next; 168 } 169 } 170 if (!sched && atomic_read(&fl_size)) 171 sched = now + FL_MAX_LINGER; 172 if (sched) { 173 mod_timer(&ip6_fl_gc_timer, sched); 174 } 175 spin_unlock(&ip6_fl_lock); 176 } 177 178 static void __net_exit ip6_fl_purge(struct net *net) 179 { 180 int i; 181 182 spin_lock(&ip6_fl_lock); 183 for (i = 0; i <= FL_HASH_MASK; i++) { 184 struct ip6_flowlabel *fl; 185 struct ip6_flowlabel __rcu **flp; 186 187 flp = &fl_ht[i]; 188 while ((fl = rcu_dereference_protected(*flp, 189 lockdep_is_held(&ip6_fl_lock))) != NULL) { 190 if (net_eq(fl->fl_net, net) && 191 atomic_read(&fl->users) == 0) { 192 *flp = fl->next; 193 fl_free(fl); 194 atomic_dec(&fl_size); 195 continue; 196 } 197 flp = &fl->next; 198 } 199 } 200 spin_unlock(&ip6_fl_lock); 201 } 202 203 static struct ip6_flowlabel *fl_intern(struct net *net, 204 struct ip6_flowlabel *fl, __be32 label) 205 { 206 struct ip6_flowlabel *lfl; 207 208 fl->label = label & IPV6_FLOWLABEL_MASK; 209 210 spin_lock_bh(&ip6_fl_lock); 211 if (label == 0) { 212 for (;;) { 213 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK; 214 if (fl->label) { 215 lfl = __fl_lookup(net, fl->label); 216 if (lfl == NULL) 217 break; 218 } 219 } 220 } else { 221 /* 222 * we dropper the ip6_fl_lock, so this entry could reappear 223 * and we need to recheck with it. 224 * 225 * OTOH no need to search the active socket first, like it is 226 * done in ipv6_flowlabel_opt - sock is locked, so new entry 227 * with the same label can only appear on another sock 228 */ 229 lfl = __fl_lookup(net, fl->label); 230 if (lfl != NULL) { 231 atomic_inc(&lfl->users); 232 spin_unlock_bh(&ip6_fl_lock); 233 return lfl; 234 } 235 } 236 237 fl->lastuse = jiffies; 238 fl->next = fl_ht[FL_HASH(fl->label)]; 239 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 240 atomic_inc(&fl_size); 241 spin_unlock_bh(&ip6_fl_lock); 242 return NULL; 243 } 244 245 246 247 /* Socket flowlabel lists */ 248 249 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label) 250 { 251 struct ipv6_fl_socklist *sfl; 252 struct ipv6_pinfo *np = inet6_sk(sk); 253 254 label &= IPV6_FLOWLABEL_MASK; 255 256 rcu_read_lock_bh(); 257 for_each_sk_fl_rcu(np, sfl) { 258 struct ip6_flowlabel *fl = sfl->fl; 259 if (fl->label == label) { 260 fl->lastuse = jiffies; 261 atomic_inc(&fl->users); 262 rcu_read_unlock_bh(); 263 return fl; 264 } 265 } 266 rcu_read_unlock_bh(); 267 return NULL; 268 } 269 270 EXPORT_SYMBOL_GPL(fl6_sock_lookup); 271 272 void fl6_free_socklist(struct sock *sk) 273 { 274 struct ipv6_pinfo *np = inet6_sk(sk); 275 struct ipv6_fl_socklist *sfl; 276 277 if (!rcu_access_pointer(np->ipv6_fl_list)) 278 return; 279 280 spin_lock_bh(&ip6_sk_fl_lock); 281 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 282 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 283 np->ipv6_fl_list = sfl->next; 284 spin_unlock_bh(&ip6_sk_fl_lock); 285 286 fl_release(sfl->fl); 287 kfree_rcu(sfl, rcu); 288 289 spin_lock_bh(&ip6_sk_fl_lock); 290 } 291 spin_unlock_bh(&ip6_sk_fl_lock); 292 } 293 294 /* Service routines */ 295 296 297 /* 298 It is the only difficult place. flowlabel enforces equal headers 299 before and including routing header, however user may supply options 300 following rthdr. 301 */ 302 303 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space, 304 struct ip6_flowlabel * fl, 305 struct ipv6_txoptions * fopt) 306 { 307 struct ipv6_txoptions * fl_opt = fl->opt; 308 309 if (fopt == NULL || fopt->opt_flen == 0) 310 return fl_opt; 311 312 if (fl_opt != NULL) { 313 opt_space->hopopt = fl_opt->hopopt; 314 opt_space->dst0opt = fl_opt->dst0opt; 315 opt_space->srcrt = fl_opt->srcrt; 316 opt_space->opt_nflen = fl_opt->opt_nflen; 317 } else { 318 if (fopt->opt_nflen == 0) 319 return fopt; 320 opt_space->hopopt = NULL; 321 opt_space->dst0opt = NULL; 322 opt_space->srcrt = NULL; 323 opt_space->opt_nflen = 0; 324 } 325 opt_space->dst1opt = fopt->dst1opt; 326 opt_space->opt_flen = fopt->opt_flen; 327 return opt_space; 328 } 329 EXPORT_SYMBOL_GPL(fl6_merge_options); 330 331 static unsigned long check_linger(unsigned long ttl) 332 { 333 if (ttl < FL_MIN_LINGER) 334 return FL_MIN_LINGER*HZ; 335 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 336 return 0; 337 return ttl*HZ; 338 } 339 340 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 341 { 342 linger = check_linger(linger); 343 if (!linger) 344 return -EPERM; 345 expires = check_linger(expires); 346 if (!expires) 347 return -EPERM; 348 349 spin_lock_bh(&ip6_fl_lock); 350 fl->lastuse = jiffies; 351 if (time_before(fl->linger, linger)) 352 fl->linger = linger; 353 if (time_before(expires, fl->linger)) 354 expires = fl->linger; 355 if (time_before(fl->expires, fl->lastuse + expires)) 356 fl->expires = fl->lastuse + expires; 357 spin_unlock_bh(&ip6_fl_lock); 358 359 return 0; 360 } 361 362 static struct ip6_flowlabel * 363 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 364 char __user *optval, int optlen, int *err_p) 365 { 366 struct ip6_flowlabel *fl = NULL; 367 int olen; 368 int addr_type; 369 int err; 370 371 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 372 err = -EINVAL; 373 if (olen > 64 * 1024) 374 goto done; 375 376 err = -ENOMEM; 377 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 378 if (fl == NULL) 379 goto done; 380 381 if (olen > 0) { 382 struct msghdr msg; 383 struct flowi6 flowi6; 384 int junk; 385 386 err = -ENOMEM; 387 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 388 if (fl->opt == NULL) 389 goto done; 390 391 memset(fl->opt, 0, sizeof(*fl->opt)); 392 fl->opt->tot_len = sizeof(*fl->opt) + olen; 393 err = -EFAULT; 394 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen)) 395 goto done; 396 397 msg.msg_controllen = olen; 398 msg.msg_control = (void*)(fl->opt+1); 399 memset(&flowi6, 0, sizeof(flowi6)); 400 401 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, fl->opt, 402 &junk, &junk, &junk); 403 if (err) 404 goto done; 405 err = -EINVAL; 406 if (fl->opt->opt_flen) 407 goto done; 408 if (fl->opt->opt_nflen == 0) { 409 kfree(fl->opt); 410 fl->opt = NULL; 411 } 412 } 413 414 fl->fl_net = hold_net(net); 415 fl->expires = jiffies; 416 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 417 if (err) 418 goto done; 419 fl->share = freq->flr_share; 420 addr_type = ipv6_addr_type(&freq->flr_dst); 421 if ((addr_type & IPV6_ADDR_MAPPED) || 422 addr_type == IPV6_ADDR_ANY) { 423 err = -EINVAL; 424 goto done; 425 } 426 fl->dst = freq->flr_dst; 427 atomic_set(&fl->users, 1); 428 switch (fl->share) { 429 case IPV6_FL_S_EXCL: 430 case IPV6_FL_S_ANY: 431 break; 432 case IPV6_FL_S_PROCESS: 433 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 434 break; 435 case IPV6_FL_S_USER: 436 fl->owner.uid = current_euid(); 437 break; 438 default: 439 err = -EINVAL; 440 goto done; 441 } 442 return fl; 443 444 done: 445 fl_free(fl); 446 *err_p = err; 447 return NULL; 448 } 449 450 static int mem_check(struct sock *sk) 451 { 452 struct ipv6_pinfo *np = inet6_sk(sk); 453 struct ipv6_fl_socklist *sfl; 454 int room = FL_MAX_SIZE - atomic_read(&fl_size); 455 int count = 0; 456 457 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 458 return 0; 459 460 rcu_read_lock_bh(); 461 for_each_sk_fl_rcu(np, sfl) 462 count++; 463 rcu_read_unlock_bh(); 464 465 if (room <= 0 || 466 ((count >= FL_MAX_PER_SOCK || 467 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 468 !capable(CAP_NET_ADMIN))) 469 return -ENOBUFS; 470 471 return 0; 472 } 473 474 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 475 struct ip6_flowlabel *fl) 476 { 477 spin_lock_bh(&ip6_sk_fl_lock); 478 sfl->fl = fl; 479 sfl->next = np->ipv6_fl_list; 480 rcu_assign_pointer(np->ipv6_fl_list, sfl); 481 spin_unlock_bh(&ip6_sk_fl_lock); 482 } 483 484 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 485 int flags) 486 { 487 struct ipv6_pinfo *np = inet6_sk(sk); 488 struct ipv6_fl_socklist *sfl; 489 490 if (flags & IPV6_FL_F_REMOTE) { 491 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 492 return 0; 493 } 494 495 if (np->repflow) { 496 freq->flr_label = np->flow_label; 497 return 0; 498 } 499 500 rcu_read_lock_bh(); 501 502 for_each_sk_fl_rcu(np, sfl) { 503 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 504 spin_lock_bh(&ip6_fl_lock); 505 freq->flr_label = sfl->fl->label; 506 freq->flr_dst = sfl->fl->dst; 507 freq->flr_share = sfl->fl->share; 508 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 509 freq->flr_linger = sfl->fl->linger / HZ; 510 511 spin_unlock_bh(&ip6_fl_lock); 512 rcu_read_unlock_bh(); 513 return 0; 514 } 515 } 516 rcu_read_unlock_bh(); 517 518 return -ENOENT; 519 } 520 521 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen) 522 { 523 int uninitialized_var(err); 524 struct net *net = sock_net(sk); 525 struct ipv6_pinfo *np = inet6_sk(sk); 526 struct in6_flowlabel_req freq; 527 struct ipv6_fl_socklist *sfl1=NULL; 528 struct ipv6_fl_socklist *sfl; 529 struct ipv6_fl_socklist __rcu **sflp; 530 struct ip6_flowlabel *fl, *fl1 = NULL; 531 532 533 if (optlen < sizeof(freq)) 534 return -EINVAL; 535 536 if (copy_from_user(&freq, optval, sizeof(freq))) 537 return -EFAULT; 538 539 switch (freq.flr_action) { 540 case IPV6_FL_A_PUT: 541 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 542 if (sk->sk_protocol != IPPROTO_TCP) 543 return -ENOPROTOOPT; 544 if (!np->repflow) 545 return -ESRCH; 546 np->flow_label = 0; 547 np->repflow = 0; 548 return 0; 549 } 550 spin_lock_bh(&ip6_sk_fl_lock); 551 for (sflp = &np->ipv6_fl_list; 552 (sfl = rcu_dereference(*sflp))!=NULL; 553 sflp = &sfl->next) { 554 if (sfl->fl->label == freq.flr_label) { 555 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK)) 556 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 557 *sflp = rcu_dereference(sfl->next); 558 spin_unlock_bh(&ip6_sk_fl_lock); 559 fl_release(sfl->fl); 560 kfree_rcu(sfl, rcu); 561 return 0; 562 } 563 } 564 spin_unlock_bh(&ip6_sk_fl_lock); 565 return -ESRCH; 566 567 case IPV6_FL_A_RENEW: 568 rcu_read_lock_bh(); 569 for_each_sk_fl_rcu(np, sfl) { 570 if (sfl->fl->label == freq.flr_label) { 571 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires); 572 rcu_read_unlock_bh(); 573 return err; 574 } 575 } 576 rcu_read_unlock_bh(); 577 578 if (freq.flr_share == IPV6_FL_S_NONE && 579 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 580 fl = fl_lookup(net, freq.flr_label); 581 if (fl) { 582 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires); 583 fl_release(fl); 584 return err; 585 } 586 } 587 return -ESRCH; 588 589 case IPV6_FL_A_GET: 590 if (freq.flr_flags & IPV6_FL_F_REFLECT) { 591 struct net *net = sock_net(sk); 592 if (net->ipv6.sysctl.flowlabel_consistency) { 593 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 594 return -EPERM; 595 } 596 597 if (sk->sk_protocol != IPPROTO_TCP) 598 return -ENOPROTOOPT; 599 600 np->repflow = 1; 601 return 0; 602 } 603 604 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK) 605 return -EINVAL; 606 607 fl = fl_create(net, sk, &freq, optval, optlen, &err); 608 if (fl == NULL) 609 return err; 610 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 611 612 if (freq.flr_label) { 613 err = -EEXIST; 614 rcu_read_lock_bh(); 615 for_each_sk_fl_rcu(np, sfl) { 616 if (sfl->fl->label == freq.flr_label) { 617 if (freq.flr_flags&IPV6_FL_F_EXCL) { 618 rcu_read_unlock_bh(); 619 goto done; 620 } 621 fl1 = sfl->fl; 622 atomic_inc(&fl1->users); 623 break; 624 } 625 } 626 rcu_read_unlock_bh(); 627 628 if (fl1 == NULL) 629 fl1 = fl_lookup(net, freq.flr_label); 630 if (fl1) { 631 recheck: 632 err = -EEXIST; 633 if (freq.flr_flags&IPV6_FL_F_EXCL) 634 goto release; 635 err = -EPERM; 636 if (fl1->share == IPV6_FL_S_EXCL || 637 fl1->share != fl->share || 638 ((fl1->share == IPV6_FL_S_PROCESS) && 639 (fl1->owner.pid == fl->owner.pid)) || 640 ((fl1->share == IPV6_FL_S_USER) && 641 uid_eq(fl1->owner.uid, fl->owner.uid))) 642 goto release; 643 644 err = -ENOMEM; 645 if (sfl1 == NULL) 646 goto release; 647 if (fl->linger > fl1->linger) 648 fl1->linger = fl->linger; 649 if ((long)(fl->expires - fl1->expires) > 0) 650 fl1->expires = fl->expires; 651 fl_link(np, sfl1, fl1); 652 fl_free(fl); 653 return 0; 654 655 release: 656 fl_release(fl1); 657 goto done; 658 } 659 } 660 err = -ENOENT; 661 if (!(freq.flr_flags&IPV6_FL_F_CREATE)) 662 goto done; 663 664 err = -ENOMEM; 665 if (sfl1 == NULL || (err = mem_check(sk)) != 0) 666 goto done; 667 668 fl1 = fl_intern(net, fl, freq.flr_label); 669 if (fl1 != NULL) 670 goto recheck; 671 672 if (!freq.flr_label) { 673 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label, 674 &fl->label, sizeof(fl->label))) { 675 /* Intentionally ignore fault. */ 676 } 677 } 678 679 fl_link(np, sfl1, fl); 680 return 0; 681 682 default: 683 return -EINVAL; 684 } 685 686 done: 687 fl_free(fl); 688 kfree(sfl1); 689 return err; 690 } 691 692 #ifdef CONFIG_PROC_FS 693 694 struct ip6fl_iter_state { 695 struct seq_net_private p; 696 struct pid_namespace *pid_ns; 697 int bucket; 698 }; 699 700 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 701 702 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 703 { 704 struct ip6_flowlabel *fl = NULL; 705 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 706 struct net *net = seq_file_net(seq); 707 708 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 709 for_each_fl_rcu(state->bucket, fl) { 710 if (net_eq(fl->fl_net, net)) 711 goto out; 712 } 713 } 714 fl = NULL; 715 out: 716 return fl; 717 } 718 719 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 720 { 721 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 722 struct net *net = seq_file_net(seq); 723 724 for_each_fl_continue_rcu(fl) { 725 if (net_eq(fl->fl_net, net)) 726 goto out; 727 } 728 729 try_again: 730 if (++state->bucket <= FL_HASH_MASK) { 731 for_each_fl_rcu(state->bucket, fl) { 732 if (net_eq(fl->fl_net, net)) 733 goto out; 734 } 735 goto try_again; 736 } 737 fl = NULL; 738 739 out: 740 return fl; 741 } 742 743 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 744 { 745 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 746 if (fl) 747 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 748 --pos; 749 return pos ? NULL : fl; 750 } 751 752 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 753 __acquires(RCU) 754 { 755 rcu_read_lock_bh(); 756 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 757 } 758 759 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 760 { 761 struct ip6_flowlabel *fl; 762 763 if (v == SEQ_START_TOKEN) 764 fl = ip6fl_get_first(seq); 765 else 766 fl = ip6fl_get_next(seq, v); 767 ++*pos; 768 return fl; 769 } 770 771 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 772 __releases(RCU) 773 { 774 rcu_read_unlock_bh(); 775 } 776 777 static int ip6fl_seq_show(struct seq_file *seq, void *v) 778 { 779 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 780 if (v == SEQ_START_TOKEN) 781 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n", 782 "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt"); 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