1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ip6_flowlabel.c IPv6 flowlabel manager. 4 * 5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 6 */ 7 8 #include <linux/capability.h> 9 #include <linux/errno.h> 10 #include <linux/types.h> 11 #include <linux/socket.h> 12 #include <linux/net.h> 13 #include <linux/netdevice.h> 14 #include <linux/in6.h> 15 #include <linux/proc_fs.h> 16 #include <linux/seq_file.h> 17 #include <linux/slab.h> 18 #include <linux/export.h> 19 #include <linux/pid_namespace.h> 20 #include <linux/jump_label_ratelimit.h> 21 22 #include <net/net_namespace.h> 23 #include <net/sock.h> 24 25 #include <net/ipv6.h> 26 #include <net/rawv6.h> 27 #include <net/transp_v6.h> 28 29 #include <linux/uaccess.h> 30 31 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified 32 in old IPv6 RFC. Well, it was reasonable value. 33 */ 34 #define FL_MAX_LINGER 150 /* Maximal linger timeout */ 35 36 /* FL hash table */ 37 38 #define FL_MAX_PER_SOCK 32 39 #define FL_MAX_SIZE 4096 40 #define FL_HASH_MASK 255 41 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK) 42 43 static atomic_t fl_size = ATOMIC_INIT(0); 44 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1]; 45 46 static void ip6_fl_gc(struct timer_list *unused); 47 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc); 48 49 /* FL hash table lock: it protects only of GC */ 50 51 static DEFINE_SPINLOCK(ip6_fl_lock); 52 53 /* Big socket sock */ 54 55 static DEFINE_SPINLOCK(ip6_sk_fl_lock); 56 57 DEFINE_STATIC_KEY_DEFERRED_FALSE(ipv6_flowlabel_exclusive, HZ); 58 EXPORT_SYMBOL(ipv6_flowlabel_exclusive); 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 static bool fl_shared_exclusive(struct ip6_flowlabel *fl) 98 { 99 return fl->share == IPV6_FL_S_EXCL || 100 fl->share == IPV6_FL_S_PROCESS || 101 fl->share == IPV6_FL_S_USER; 102 } 103 104 static void fl_free_rcu(struct rcu_head *head) 105 { 106 struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu); 107 108 if (fl->share == IPV6_FL_S_PROCESS) 109 put_pid(fl->owner.pid); 110 kfree(fl->opt); 111 kfree(fl); 112 } 113 114 115 static void fl_free(struct ip6_flowlabel *fl) 116 { 117 if (!fl) 118 return; 119 120 if (fl_shared_exclusive(fl) || fl->opt) 121 static_branch_slow_dec_deferred(&ipv6_flowlabel_exclusive); 122 123 call_rcu(&fl->rcu, fl_free_rcu); 124 } 125 126 static void fl_release(struct ip6_flowlabel *fl) 127 { 128 spin_lock_bh(&ip6_fl_lock); 129 130 fl->lastuse = jiffies; 131 if (atomic_dec_and_test(&fl->users)) { 132 unsigned long ttd = fl->lastuse + fl->linger; 133 if (time_after(ttd, fl->expires)) 134 fl->expires = ttd; 135 ttd = fl->expires; 136 if (fl->opt && fl->share == IPV6_FL_S_EXCL) { 137 struct ipv6_txoptions *opt = fl->opt; 138 fl->opt = NULL; 139 kfree(opt); 140 } 141 if (!timer_pending(&ip6_fl_gc_timer) || 142 time_after(ip6_fl_gc_timer.expires, ttd)) 143 mod_timer(&ip6_fl_gc_timer, ttd); 144 } 145 spin_unlock_bh(&ip6_fl_lock); 146 } 147 148 static void ip6_fl_gc(struct timer_list *unused) 149 { 150 int i; 151 unsigned long now = jiffies; 152 unsigned long sched = 0; 153 154 spin_lock(&ip6_fl_lock); 155 156 for (i = 0; i <= FL_HASH_MASK; i++) { 157 struct ip6_flowlabel *fl; 158 struct ip6_flowlabel __rcu **flp; 159 160 flp = &fl_ht[i]; 161 while ((fl = rcu_dereference_protected(*flp, 162 lockdep_is_held(&ip6_fl_lock))) != NULL) { 163 if (atomic_read(&fl->users) == 0) { 164 unsigned long ttd = fl->lastuse + fl->linger; 165 if (time_after(ttd, fl->expires)) 166 fl->expires = ttd; 167 ttd = fl->expires; 168 if (time_after_eq(now, ttd)) { 169 *flp = fl->next; 170 fl_free(fl); 171 atomic_dec(&fl_size); 172 continue; 173 } 174 if (!sched || time_before(ttd, sched)) 175 sched = ttd; 176 } 177 flp = &fl->next; 178 } 179 } 180 if (!sched && atomic_read(&fl_size)) 181 sched = now + FL_MAX_LINGER; 182 if (sched) { 183 mod_timer(&ip6_fl_gc_timer, sched); 184 } 185 spin_unlock(&ip6_fl_lock); 186 } 187 188 static void __net_exit ip6_fl_purge(struct net *net) 189 { 190 int i; 191 192 spin_lock_bh(&ip6_fl_lock); 193 for (i = 0; i <= FL_HASH_MASK; i++) { 194 struct ip6_flowlabel *fl; 195 struct ip6_flowlabel __rcu **flp; 196 197 flp = &fl_ht[i]; 198 while ((fl = rcu_dereference_protected(*flp, 199 lockdep_is_held(&ip6_fl_lock))) != NULL) { 200 if (net_eq(fl->fl_net, net) && 201 atomic_read(&fl->users) == 0) { 202 *flp = fl->next; 203 fl_free(fl); 204 atomic_dec(&fl_size); 205 continue; 206 } 207 flp = &fl->next; 208 } 209 } 210 spin_unlock_bh(&ip6_fl_lock); 211 } 212 213 static struct ip6_flowlabel *fl_intern(struct net *net, 214 struct ip6_flowlabel *fl, __be32 label) 215 { 216 struct ip6_flowlabel *lfl; 217 218 fl->label = label & IPV6_FLOWLABEL_MASK; 219 220 spin_lock_bh(&ip6_fl_lock); 221 if (label == 0) { 222 for (;;) { 223 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK; 224 if (fl->label) { 225 lfl = __fl_lookup(net, fl->label); 226 if (!lfl) 227 break; 228 } 229 } 230 } else { 231 /* 232 * we dropper the ip6_fl_lock, so this entry could reappear 233 * and we need to recheck with it. 234 * 235 * OTOH no need to search the active socket first, like it is 236 * done in ipv6_flowlabel_opt - sock is locked, so new entry 237 * with the same label can only appear on another sock 238 */ 239 lfl = __fl_lookup(net, fl->label); 240 if (lfl) { 241 atomic_inc(&lfl->users); 242 spin_unlock_bh(&ip6_fl_lock); 243 return lfl; 244 } 245 } 246 247 fl->lastuse = jiffies; 248 fl->next = fl_ht[FL_HASH(fl->label)]; 249 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 250 atomic_inc(&fl_size); 251 spin_unlock_bh(&ip6_fl_lock); 252 return NULL; 253 } 254 255 256 257 /* Socket flowlabel lists */ 258 259 struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label) 260 { 261 struct ipv6_fl_socklist *sfl; 262 struct ipv6_pinfo *np = inet6_sk(sk); 263 264 label &= IPV6_FLOWLABEL_MASK; 265 266 rcu_read_lock_bh(); 267 for_each_sk_fl_rcu(np, sfl) { 268 struct ip6_flowlabel *fl = sfl->fl; 269 270 if (fl->label == label && atomic_inc_not_zero(&fl->users)) { 271 fl->lastuse = jiffies; 272 rcu_read_unlock_bh(); 273 return fl; 274 } 275 } 276 rcu_read_unlock_bh(); 277 return NULL; 278 } 279 EXPORT_SYMBOL_GPL(__fl6_sock_lookup); 280 281 void fl6_free_socklist(struct sock *sk) 282 { 283 struct ipv6_pinfo *np = inet6_sk(sk); 284 struct ipv6_fl_socklist *sfl; 285 286 if (!rcu_access_pointer(np->ipv6_fl_list)) 287 return; 288 289 spin_lock_bh(&ip6_sk_fl_lock); 290 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 291 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 292 np->ipv6_fl_list = sfl->next; 293 spin_unlock_bh(&ip6_sk_fl_lock); 294 295 fl_release(sfl->fl); 296 kfree_rcu(sfl, rcu); 297 298 spin_lock_bh(&ip6_sk_fl_lock); 299 } 300 spin_unlock_bh(&ip6_sk_fl_lock); 301 } 302 303 /* Service routines */ 304 305 306 /* 307 It is the only difficult place. flowlabel enforces equal headers 308 before and including routing header, however user may supply options 309 following rthdr. 310 */ 311 312 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 313 struct ip6_flowlabel *fl, 314 struct ipv6_txoptions *fopt) 315 { 316 struct ipv6_txoptions *fl_opt = fl->opt; 317 318 if (!fopt || fopt->opt_flen == 0) 319 return fl_opt; 320 321 if (fl_opt) { 322 opt_space->hopopt = fl_opt->hopopt; 323 opt_space->dst0opt = fl_opt->dst0opt; 324 opt_space->srcrt = fl_opt->srcrt; 325 opt_space->opt_nflen = fl_opt->opt_nflen; 326 } else { 327 if (fopt->opt_nflen == 0) 328 return fopt; 329 opt_space->hopopt = NULL; 330 opt_space->dst0opt = NULL; 331 opt_space->srcrt = NULL; 332 opt_space->opt_nflen = 0; 333 } 334 opt_space->dst1opt = fopt->dst1opt; 335 opt_space->opt_flen = fopt->opt_flen; 336 opt_space->tot_len = fopt->tot_len; 337 return opt_space; 338 } 339 EXPORT_SYMBOL_GPL(fl6_merge_options); 340 341 static unsigned long check_linger(unsigned long ttl) 342 { 343 if (ttl < FL_MIN_LINGER) 344 return FL_MIN_LINGER*HZ; 345 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 346 return 0; 347 return ttl*HZ; 348 } 349 350 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 351 { 352 linger = check_linger(linger); 353 if (!linger) 354 return -EPERM; 355 expires = check_linger(expires); 356 if (!expires) 357 return -EPERM; 358 359 spin_lock_bh(&ip6_fl_lock); 360 fl->lastuse = jiffies; 361 if (time_before(fl->linger, linger)) 362 fl->linger = linger; 363 if (time_before(expires, fl->linger)) 364 expires = fl->linger; 365 if (time_before(fl->expires, fl->lastuse + expires)) 366 fl->expires = fl->lastuse + expires; 367 spin_unlock_bh(&ip6_fl_lock); 368 369 return 0; 370 } 371 372 static struct ip6_flowlabel * 373 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 374 sockptr_t optval, int optlen, int *err_p) 375 { 376 struct ip6_flowlabel *fl = NULL; 377 int olen; 378 int addr_type; 379 int err; 380 381 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 382 err = -EINVAL; 383 if (olen > 64 * 1024) 384 goto done; 385 386 err = -ENOMEM; 387 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 388 if (!fl) 389 goto done; 390 391 if (olen > 0) { 392 struct msghdr msg; 393 struct flowi6 flowi6; 394 struct ipcm6_cookie ipc6; 395 396 err = -ENOMEM; 397 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 398 if (!fl->opt) 399 goto done; 400 401 memset(fl->opt, 0, sizeof(*fl->opt)); 402 fl->opt->tot_len = sizeof(*fl->opt) + olen; 403 err = -EFAULT; 404 sockptr_advance(optval, CMSG_ALIGN(sizeof(*freq))); 405 if (copy_from_sockptr(fl->opt + 1, optval, olen)) 406 goto done; 407 408 msg.msg_controllen = olen; 409 msg.msg_control = (void *)(fl->opt+1); 410 memset(&flowi6, 0, sizeof(flowi6)); 411 412 ipc6.opt = fl->opt; 413 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6); 414 if (err) 415 goto done; 416 err = -EINVAL; 417 if (fl->opt->opt_flen) 418 goto done; 419 if (fl->opt->opt_nflen == 0) { 420 kfree(fl->opt); 421 fl->opt = NULL; 422 } 423 } 424 425 fl->fl_net = net; 426 fl->expires = jiffies; 427 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 428 if (err) 429 goto done; 430 fl->share = freq->flr_share; 431 addr_type = ipv6_addr_type(&freq->flr_dst); 432 if ((addr_type & IPV6_ADDR_MAPPED) || 433 addr_type == IPV6_ADDR_ANY) { 434 err = -EINVAL; 435 goto done; 436 } 437 fl->dst = freq->flr_dst; 438 atomic_set(&fl->users, 1); 439 switch (fl->share) { 440 case IPV6_FL_S_EXCL: 441 case IPV6_FL_S_ANY: 442 break; 443 case IPV6_FL_S_PROCESS: 444 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 445 break; 446 case IPV6_FL_S_USER: 447 fl->owner.uid = current_euid(); 448 break; 449 default: 450 err = -EINVAL; 451 goto done; 452 } 453 if (fl_shared_exclusive(fl) || fl->opt) 454 static_branch_deferred_inc(&ipv6_flowlabel_exclusive); 455 return fl; 456 457 done: 458 if (fl) { 459 kfree(fl->opt); 460 kfree(fl); 461 } 462 *err_p = err; 463 return NULL; 464 } 465 466 static int mem_check(struct sock *sk) 467 { 468 struct ipv6_pinfo *np = inet6_sk(sk); 469 struct ipv6_fl_socklist *sfl; 470 int room = FL_MAX_SIZE - atomic_read(&fl_size); 471 int count = 0; 472 473 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 474 return 0; 475 476 rcu_read_lock_bh(); 477 for_each_sk_fl_rcu(np, sfl) 478 count++; 479 rcu_read_unlock_bh(); 480 481 if (room <= 0 || 482 ((count >= FL_MAX_PER_SOCK || 483 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 484 !capable(CAP_NET_ADMIN))) 485 return -ENOBUFS; 486 487 return 0; 488 } 489 490 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 491 struct ip6_flowlabel *fl) 492 { 493 spin_lock_bh(&ip6_sk_fl_lock); 494 sfl->fl = fl; 495 sfl->next = np->ipv6_fl_list; 496 rcu_assign_pointer(np->ipv6_fl_list, sfl); 497 spin_unlock_bh(&ip6_sk_fl_lock); 498 } 499 500 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 501 int flags) 502 { 503 struct ipv6_pinfo *np = inet6_sk(sk); 504 struct ipv6_fl_socklist *sfl; 505 506 if (flags & IPV6_FL_F_REMOTE) { 507 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 508 return 0; 509 } 510 511 if (np->repflow) { 512 freq->flr_label = np->flow_label; 513 return 0; 514 } 515 516 rcu_read_lock_bh(); 517 518 for_each_sk_fl_rcu(np, sfl) { 519 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 520 spin_lock_bh(&ip6_fl_lock); 521 freq->flr_label = sfl->fl->label; 522 freq->flr_dst = sfl->fl->dst; 523 freq->flr_share = sfl->fl->share; 524 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 525 freq->flr_linger = sfl->fl->linger / HZ; 526 527 spin_unlock_bh(&ip6_fl_lock); 528 rcu_read_unlock_bh(); 529 return 0; 530 } 531 } 532 rcu_read_unlock_bh(); 533 534 return -ENOENT; 535 } 536 537 #define socklist_dereference(__sflp) \ 538 rcu_dereference_protected(__sflp, lockdep_is_held(&ip6_sk_fl_lock)) 539 540 static int ipv6_flowlabel_put(struct sock *sk, struct in6_flowlabel_req *freq) 541 { 542 struct ipv6_pinfo *np = inet6_sk(sk); 543 struct ipv6_fl_socklist __rcu **sflp; 544 struct ipv6_fl_socklist *sfl; 545 546 if (freq->flr_flags & IPV6_FL_F_REFLECT) { 547 if (sk->sk_protocol != IPPROTO_TCP) 548 return -ENOPROTOOPT; 549 if (!np->repflow) 550 return -ESRCH; 551 np->flow_label = 0; 552 np->repflow = 0; 553 return 0; 554 } 555 556 spin_lock_bh(&ip6_sk_fl_lock); 557 for (sflp = &np->ipv6_fl_list; 558 (sfl = socklist_dereference(*sflp)) != NULL; 559 sflp = &sfl->next) { 560 if (sfl->fl->label == freq->flr_label) 561 goto found; 562 } 563 spin_unlock_bh(&ip6_sk_fl_lock); 564 return -ESRCH; 565 found: 566 if (freq->flr_label == (np->flow_label & IPV6_FLOWLABEL_MASK)) 567 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 568 *sflp = sfl->next; 569 spin_unlock_bh(&ip6_sk_fl_lock); 570 fl_release(sfl->fl); 571 kfree_rcu(sfl, rcu); 572 return 0; 573 } 574 575 static int ipv6_flowlabel_renew(struct sock *sk, struct in6_flowlabel_req *freq) 576 { 577 struct ipv6_pinfo *np = inet6_sk(sk); 578 struct net *net = sock_net(sk); 579 struct ipv6_fl_socklist *sfl; 580 int err; 581 582 rcu_read_lock_bh(); 583 for_each_sk_fl_rcu(np, sfl) { 584 if (sfl->fl->label == freq->flr_label) { 585 err = fl6_renew(sfl->fl, freq->flr_linger, 586 freq->flr_expires); 587 rcu_read_unlock_bh(); 588 return err; 589 } 590 } 591 rcu_read_unlock_bh(); 592 593 if (freq->flr_share == IPV6_FL_S_NONE && 594 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 595 struct ip6_flowlabel *fl = fl_lookup(net, freq->flr_label); 596 597 if (fl) { 598 err = fl6_renew(fl, freq->flr_linger, 599 freq->flr_expires); 600 fl_release(fl); 601 return err; 602 } 603 } 604 return -ESRCH; 605 } 606 607 static int ipv6_flowlabel_get(struct sock *sk, struct in6_flowlabel_req *freq, 608 sockptr_t optval, int optlen) 609 { 610 struct ipv6_fl_socklist *sfl, *sfl1 = NULL; 611 struct ip6_flowlabel *fl, *fl1 = NULL; 612 struct ipv6_pinfo *np = inet6_sk(sk); 613 struct net *net = sock_net(sk); 614 int uninitialized_var(err); 615 616 if (freq->flr_flags & IPV6_FL_F_REFLECT) { 617 if (net->ipv6.sysctl.flowlabel_consistency) { 618 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 619 return -EPERM; 620 } 621 622 if (sk->sk_protocol != IPPROTO_TCP) 623 return -ENOPROTOOPT; 624 np->repflow = 1; 625 return 0; 626 } 627 628 if (freq->flr_label & ~IPV6_FLOWLABEL_MASK) 629 return -EINVAL; 630 if (net->ipv6.sysctl.flowlabel_state_ranges && 631 (freq->flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 632 return -ERANGE; 633 634 fl = fl_create(net, sk, freq, optval, optlen, &err); 635 if (!fl) 636 return err; 637 638 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 639 640 if (freq->flr_label) { 641 err = -EEXIST; 642 rcu_read_lock_bh(); 643 for_each_sk_fl_rcu(np, sfl) { 644 if (sfl->fl->label == freq->flr_label) { 645 if (freq->flr_flags & IPV6_FL_F_EXCL) { 646 rcu_read_unlock_bh(); 647 goto done; 648 } 649 fl1 = sfl->fl; 650 if (!atomic_inc_not_zero(&fl1->users)) 651 fl1 = NULL; 652 break; 653 } 654 } 655 rcu_read_unlock_bh(); 656 657 if (!fl1) 658 fl1 = fl_lookup(net, freq->flr_label); 659 if (fl1) { 660 recheck: 661 err = -EEXIST; 662 if (freq->flr_flags&IPV6_FL_F_EXCL) 663 goto release; 664 err = -EPERM; 665 if (fl1->share == IPV6_FL_S_EXCL || 666 fl1->share != fl->share || 667 ((fl1->share == IPV6_FL_S_PROCESS) && 668 (fl1->owner.pid != fl->owner.pid)) || 669 ((fl1->share == IPV6_FL_S_USER) && 670 !uid_eq(fl1->owner.uid, fl->owner.uid))) 671 goto release; 672 673 err = -ENOMEM; 674 if (!sfl1) 675 goto release; 676 if (fl->linger > fl1->linger) 677 fl1->linger = fl->linger; 678 if ((long)(fl->expires - fl1->expires) > 0) 679 fl1->expires = fl->expires; 680 fl_link(np, sfl1, fl1); 681 fl_free(fl); 682 return 0; 683 684 release: 685 fl_release(fl1); 686 goto done; 687 } 688 } 689 err = -ENOENT; 690 if (!(freq->flr_flags & IPV6_FL_F_CREATE)) 691 goto done; 692 693 err = -ENOMEM; 694 if (!sfl1) 695 goto done; 696 697 err = mem_check(sk); 698 if (err != 0) 699 goto done; 700 701 fl1 = fl_intern(net, fl, freq->flr_label); 702 if (fl1) 703 goto recheck; 704 705 if (!freq->flr_label) { 706 sockptr_advance(optval, 707 offsetof(struct in6_flowlabel_req, flr_label)); 708 if (copy_to_sockptr(optval, &fl->label, sizeof(fl->label))) { 709 /* Intentionally ignore fault. */ 710 } 711 } 712 713 fl_link(np, sfl1, fl); 714 return 0; 715 done: 716 fl_free(fl); 717 kfree(sfl1); 718 return err; 719 } 720 721 int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen) 722 { 723 struct in6_flowlabel_req freq; 724 725 if (optlen < sizeof(freq)) 726 return -EINVAL; 727 if (copy_from_sockptr(&freq, optval, sizeof(freq))) 728 return -EFAULT; 729 730 switch (freq.flr_action) { 731 case IPV6_FL_A_PUT: 732 return ipv6_flowlabel_put(sk, &freq); 733 case IPV6_FL_A_RENEW: 734 return ipv6_flowlabel_renew(sk, &freq); 735 case IPV6_FL_A_GET: 736 return ipv6_flowlabel_get(sk, &freq, optval, optlen); 737 default: 738 return -EINVAL; 739 } 740 } 741 742 #ifdef CONFIG_PROC_FS 743 744 struct ip6fl_iter_state { 745 struct seq_net_private p; 746 struct pid_namespace *pid_ns; 747 int bucket; 748 }; 749 750 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 751 752 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 753 { 754 struct ip6_flowlabel *fl = NULL; 755 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 756 struct net *net = seq_file_net(seq); 757 758 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 759 for_each_fl_rcu(state->bucket, fl) { 760 if (net_eq(fl->fl_net, net)) 761 goto out; 762 } 763 } 764 fl = NULL; 765 out: 766 return fl; 767 } 768 769 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 770 { 771 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 772 struct net *net = seq_file_net(seq); 773 774 for_each_fl_continue_rcu(fl) { 775 if (net_eq(fl->fl_net, net)) 776 goto out; 777 } 778 779 try_again: 780 if (++state->bucket <= FL_HASH_MASK) { 781 for_each_fl_rcu(state->bucket, fl) { 782 if (net_eq(fl->fl_net, net)) 783 goto out; 784 } 785 goto try_again; 786 } 787 fl = NULL; 788 789 out: 790 return fl; 791 } 792 793 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 794 { 795 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 796 if (fl) 797 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 798 --pos; 799 return pos ? NULL : fl; 800 } 801 802 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 803 __acquires(RCU) 804 { 805 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 806 807 state->pid_ns = proc_pid_ns(file_inode(seq->file)->i_sb); 808 809 rcu_read_lock_bh(); 810 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 811 } 812 813 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 814 { 815 struct ip6_flowlabel *fl; 816 817 if (v == SEQ_START_TOKEN) 818 fl = ip6fl_get_first(seq); 819 else 820 fl = ip6fl_get_next(seq, v); 821 ++*pos; 822 return fl; 823 } 824 825 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 826 __releases(RCU) 827 { 828 rcu_read_unlock_bh(); 829 } 830 831 static int ip6fl_seq_show(struct seq_file *seq, void *v) 832 { 833 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 834 if (v == SEQ_START_TOKEN) { 835 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 836 } else { 837 struct ip6_flowlabel *fl = v; 838 seq_printf(seq, 839 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 840 (unsigned int)ntohl(fl->label), 841 fl->share, 842 ((fl->share == IPV6_FL_S_PROCESS) ? 843 pid_nr_ns(fl->owner.pid, state->pid_ns) : 844 ((fl->share == IPV6_FL_S_USER) ? 845 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 846 0)), 847 atomic_read(&fl->users), 848 fl->linger/HZ, 849 (long)(fl->expires - jiffies)/HZ, 850 &fl->dst, 851 fl->opt ? fl->opt->opt_nflen : 0); 852 } 853 return 0; 854 } 855 856 static const struct seq_operations ip6fl_seq_ops = { 857 .start = ip6fl_seq_start, 858 .next = ip6fl_seq_next, 859 .stop = ip6fl_seq_stop, 860 .show = ip6fl_seq_show, 861 }; 862 863 static int __net_init ip6_flowlabel_proc_init(struct net *net) 864 { 865 if (!proc_create_net("ip6_flowlabel", 0444, net->proc_net, 866 &ip6fl_seq_ops, sizeof(struct ip6fl_iter_state))) 867 return -ENOMEM; 868 return 0; 869 } 870 871 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 872 { 873 remove_proc_entry("ip6_flowlabel", net->proc_net); 874 } 875 #else 876 static inline int ip6_flowlabel_proc_init(struct net *net) 877 { 878 return 0; 879 } 880 static inline void ip6_flowlabel_proc_fini(struct net *net) 881 { 882 } 883 #endif 884 885 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 886 { 887 ip6_fl_purge(net); 888 ip6_flowlabel_proc_fini(net); 889 } 890 891 static struct pernet_operations ip6_flowlabel_net_ops = { 892 .init = ip6_flowlabel_proc_init, 893 .exit = ip6_flowlabel_net_exit, 894 }; 895 896 int ip6_flowlabel_init(void) 897 { 898 return register_pernet_subsys(&ip6_flowlabel_net_ops); 899 } 900 901 void ip6_flowlabel_cleanup(void) 902 { 903 static_key_deferred_flush(&ipv6_flowlabel_exclusive); 904 del_timer(&ip6_fl_gc_timer); 905 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 906 } 907