git.oblomov.eu Git - linux-2.6/blob - net/ipv6/ip6_flowlabel.c

   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/config.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
  24 #include <net/sock.h>
  25
  26 #include <net/ipv6.h>
  27 #include <net/ndisc.h>
  28 #include <net/protocol.h>
  29 #include <net/ip6_route.h>
  30 #include <net/addrconf.h>
  31 #include <net/rawv6.h>
  32 #include <net/icmp.h>
  33 #include <net/transp_v6.h>
  34
  35 #include <asm/uaccess.h>
  36
  37 #define FL_MIN_LINGER   6       /* Minimal linger. It is set to 6sec specified
  38                                    in old IPv6 RFC. Well, it was reasonable value.
  39                                  */
  40 #define FL_MAX_LINGER   60      /* Maximal linger timeout */
  41
  42 /* FL hash table */
  43
  44 #define FL_MAX_PER_SOCK 32
  45 #define FL_MAX_SIZE     4096
  46 #define FL_HASH_MASK    255
  47 #define FL_HASH(l)      (ntohl(l)&FL_HASH_MASK)
  48
  49 static atomic_t fl_size = ATOMIC_INIT(0);
  50 static struct ip6_flowlabel *fl_ht[FL_HASH_MASK+1];
  51
  52 static void ip6_fl_gc(unsigned long dummy);
  53 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);
  54
  55 /* FL hash table lock: it protects only of GC */
  56
  57 static DEFINE_RWLOCK(ip6_fl_lock);
  58
  59 /* Big socket sock */
  60
  61 static DEFINE_RWLOCK(ip6_sk_fl_lock);
  62
  63
  64 static __inline__ struct ip6_flowlabel * __fl_lookup(u32 label)
  65 {
  66         struct ip6_flowlabel *fl;
  67
  68         for (fl=fl_ht[FL_HASH(label)]; fl; fl = fl->next) {
  69                 if (fl->label == label)
  70                         return fl;
  71         }
  72         return NULL;
  73 }
  74
  75 static struct ip6_flowlabel * fl_lookup(u32 label)
  76 {
  77         struct ip6_flowlabel *fl;
  78
  79         read_lock_bh(&ip6_fl_lock);
  80         fl = __fl_lookup(label);
  81         if (fl)
  82                 atomic_inc(&fl->users);
  83         read_unlock_bh(&ip6_fl_lock);
  84         return fl;
  85 }
  86
  87
  88 static void fl_free(struct ip6_flowlabel *fl)
  89 {
  90         if (fl)
  91                 kfree(fl->opt);
  92         kfree(fl);
  93 }
  94
  95 static void fl_release(struct ip6_flowlabel *fl)
  96 {
  97         write_lock_bh(&ip6_fl_lock);
  98
  99         fl->lastuse = jiffies;
 100         if (atomic_dec_and_test(&fl->users)) {
 101                 unsigned long ttd = fl->lastuse + fl->linger;
 102                 if (time_after(ttd, fl->expires))
 103                         fl->expires = ttd;
 104                 ttd = fl->expires;
 105                 if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
 106                         struct ipv6_txoptions *opt = fl->opt;
 107                         fl->opt = NULL;
 108                         kfree(opt);
 109                 }
 110                 if (!timer_pending(&ip6_fl_gc_timer) ||
 111                     time_after(ip6_fl_gc_timer.expires, ttd))
 112                         mod_timer(&ip6_fl_gc_timer, ttd);
 113         }
 114
 115         write_unlock_bh(&ip6_fl_lock);
 116 }
 117
 118 static void ip6_fl_gc(unsigned long dummy)
 119 {
 120         int i;
 121         unsigned long now = jiffies;
 122         unsigned long sched = 0;
 123
 124         write_lock(&ip6_fl_lock);
 125
 126         for (i=0; i<=FL_HASH_MASK; i++) {
 127                 struct ip6_flowlabel *fl, **flp;
 128                 flp = &fl_ht[i];
 129                 while ((fl=*flp) != NULL) {
 130                         if (atomic_read(&fl->users) == 0) {
 131                                 unsigned long ttd = fl->lastuse + fl->linger;
 132                                 if (time_after(ttd, fl->expires))
 133                                         fl->expires = ttd;
 134                                 ttd = fl->expires;
 135                                 if (time_after_eq(now, ttd)) {
 136                                         *flp = fl->next;
 137                                         fl_free(fl);
 138                                         atomic_dec(&fl_size);
 139                                         continue;
 140                                 }
 141                                 if (!sched || time_before(ttd, sched))
 142                                         sched = ttd;
 143                         }
 144                         flp = &fl->next;
 145                 }
 146         }
 147         if (!sched && atomic_read(&fl_size))
 148                 sched = now + FL_MAX_LINGER;
 149         if (sched) {
 150                 ip6_fl_gc_timer.expires = sched;
 151                 add_timer(&ip6_fl_gc_timer);
 152         }
 153         write_unlock(&ip6_fl_lock);
 154 }
 155
 156 static int fl_intern(struct ip6_flowlabel *fl, __u32 label)
 157 {
 158         fl->label = label & IPV6_FLOWLABEL_MASK;
 159
 160         write_lock_bh(&ip6_fl_lock);
 161         if (label == 0) {
 162                 for (;;) {
 163                         fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
 164                         if (fl->label) {
 165                                 struct ip6_flowlabel *lfl;
 166                                 lfl = __fl_lookup(fl->label);
 167                                 if (lfl == NULL)
 168                                         break;
 169                         }
 170                 }
 171         }
 172
 173         fl->lastuse = jiffies;
 174         fl->next = fl_ht[FL_HASH(fl->label)];
 175         fl_ht[FL_HASH(fl->label)] = fl;
 176         atomic_inc(&fl_size);
 177         write_unlock_bh(&ip6_fl_lock);
 178         return 0;
 179 }
 180
 181
 182
 183 /* Socket flowlabel lists */
 184
 185 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, u32 label)
 186 {
 187         struct ipv6_fl_socklist *sfl;
 188         struct ipv6_pinfo *np = inet6_sk(sk);
 189
 190         label &= IPV6_FLOWLABEL_MASK;
 191
 192         for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
 193                 struct ip6_flowlabel *fl = sfl->fl;
 194                 if (fl->label == label) {
 195                         fl->lastuse = jiffies;
 196                         atomic_inc(&fl->users);
 197                         return fl;
 198                 }
 199         }
 200         return NULL;
 201 }
 202
 203 EXPORT_SYMBOL_GPL(fl6_sock_lookup);
 204
 205 void fl6_free_socklist(struct sock *sk)
 206 {
 207         struct ipv6_pinfo *np = inet6_sk(sk);
 208         struct ipv6_fl_socklist *sfl;
 209
 210         while ((sfl = np->ipv6_fl_list) != NULL) {
 211                 np->ipv6_fl_list = sfl->next;
 212                 fl_release(sfl->fl);
 213                 kfree(sfl);
 214         }
 215 }
 216
 217 /* Service routines */
 218
 219
 220 /*
 221    It is the only difficult place. flowlabel enforces equal headers
 222    before and including routing header, however user may supply options
 223    following rthdr.
 224  */
 225
 226 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
 227                                          struct ip6_flowlabel * fl,
 228                                          struct ipv6_txoptions * fopt)
 229 {
 230         struct ipv6_txoptions * fl_opt = fl->opt;
 231
 232         if (fopt == NULL || fopt->opt_flen == 0)
 233                 return fl_opt;
 234
 235         if (fl_opt != NULL) {
 236                 opt_space->hopopt = fl_opt->hopopt;
 237                 opt_space->dst0opt = fl_opt->dst0opt;
 238                 opt_space->srcrt = fl_opt->srcrt;
 239                 opt_space->opt_nflen = fl_opt->opt_nflen;
 240         } else {
 241                 if (fopt->opt_nflen == 0)
 242                         return fopt;
 243                 opt_space->hopopt = NULL;
 244                 opt_space->dst0opt = NULL;
 245                 opt_space->srcrt = NULL;
 246                 opt_space->opt_nflen = 0;
 247         }
 248         opt_space->dst1opt = fopt->dst1opt;
 249         opt_space->opt_flen = fopt->opt_flen;
 250         return opt_space;
 251 }
 252
 253 static unsigned long check_linger(unsigned long ttl)
 254 {
 255         if (ttl < FL_MIN_LINGER)
 256                 return FL_MIN_LINGER*HZ;
 257         if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
 258                 return 0;
 259         return ttl*HZ;
 260 }
 261
 262 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
 263 {
 264         linger = check_linger(linger);
 265         if (!linger)
 266                 return -EPERM;
 267         expires = check_linger(expires);
 268         if (!expires)
 269                 return -EPERM;
 270         fl->lastuse = jiffies;
 271         if (time_before(fl->linger, linger))
 272                 fl->linger = linger;
 273         if (time_before(expires, fl->linger))
 274                 expires = fl->linger;
 275         if (time_before(fl->expires, fl->lastuse + expires))
 276                 fl->expires = fl->lastuse + expires;
 277         return 0;
 278 }
 279
 280 static struct ip6_flowlabel *
 281 fl_create(struct in6_flowlabel_req *freq, char __user *optval, int optlen, int *err_p)
 282 {
 283         struct ip6_flowlabel *fl;
 284         int olen;
 285         int addr_type;
 286         int err;
 287
 288         err = -ENOMEM;
 289         fl = kmalloc(sizeof(*fl), GFP_KERNEL);
 290         if (fl == NULL)
 291                 goto done;
 292         memset(fl, 0, sizeof(*fl));
 293
 294         olen = optlen - CMSG_ALIGN(sizeof(*freq));
 295         if (olen > 0) {
 296                 struct msghdr msg;
 297                 struct flowi flowi;
 298                 int junk;
 299
 300                 err = -ENOMEM;
 301                 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
 302                 if (fl->opt == NULL)
 303                         goto done;
 304
 305                 memset(fl->opt, 0, sizeof(*fl->opt));
 306                 fl->opt->tot_len = sizeof(*fl->opt) + olen;
 307                 err = -EFAULT;
 308                 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
 309                         goto done;
 310
 311                 msg.msg_controllen = olen;
 312                 msg.msg_control = (void*)(fl->opt+1);
 313                 flowi.oif = 0;
 314
 315                 err = datagram_send_ctl(&msg, &flowi, fl->opt, &junk, &junk);
 316                 if (err)
 317                         goto done;
 318                 err = -EINVAL;
 319                 if (fl->opt->opt_flen)
 320                         goto done;
 321                 if (fl->opt->opt_nflen == 0) {
 322                         kfree(fl->opt);
 323                         fl->opt = NULL;
 324                 }
 325         }
 326
 327         fl->expires = jiffies;
 328         err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
 329         if (err)
 330                 goto done;
 331         fl->share = freq->flr_share;
 332         addr_type = ipv6_addr_type(&freq->flr_dst);
 333         if ((addr_type&IPV6_ADDR_MAPPED)
 334             || addr_type == IPV6_ADDR_ANY)
 335                 goto done;
 336         ipv6_addr_copy(&fl->dst, &freq->flr_dst);
 337         atomic_set(&fl->users, 1);
 338         switch (fl->share) {
 339         case IPV6_FL_S_EXCL:
 340         case IPV6_FL_S_ANY:
 341                 break;
 342         case IPV6_FL_S_PROCESS:
 343                 fl->owner = current->pid;
 344                 break;
 345         case IPV6_FL_S_USER:
 346                 fl->owner = current->euid;
 347                 break;
 348         default:
 349                 err = -EINVAL;
 350                 goto done;
 351         }
 352         return fl;
 353
 354 done:
 355         fl_free(fl);
 356         *err_p = err;
 357         return NULL;
 358 }
 359
 360 static int mem_check(struct sock *sk)
 361 {
 362         struct ipv6_pinfo *np = inet6_sk(sk);
 363         struct ipv6_fl_socklist *sfl;
 364         int room = FL_MAX_SIZE - atomic_read(&fl_size);
 365         int count = 0;
 366
 367         if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
 368                 return 0;
 369
 370         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next)
 371                 count++;
 372
 373         if (room <= 0 ||
 374             ((count >= FL_MAX_PER_SOCK ||
 375              (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4)
 376              && !capable(CAP_NET_ADMIN)))
 377                 return -ENOBUFS;
 378
 379         return 0;
 380 }
 381
 382 static int ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2)
 383 {
 384         if (h1 == h2)
 385                 return 0;
 386         if (h1 == NULL || h2 == NULL)
 387                 return 1;
 388         if (h1->hdrlen != h2->hdrlen)
 389                 return 1;
 390         return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1));
 391 }
 392
 393 static int ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
 394 {
 395         if (o1 == o2)
 396                 return 0;
 397         if (o1 == NULL || o2 == NULL)
 398                 return 1;
 399         if (o1->opt_nflen != o2->opt_nflen)
 400                 return 1;
 401         if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt))
 402                 return 1;
 403         if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt))
 404                 return 1;
 405         if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt))
 406                 return 1;
 407         return 0;
 408 }
 409
 410 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
 411 {
 412         int err;
 413         struct ipv6_pinfo *np = inet6_sk(sk);
 414         struct in6_flowlabel_req freq;
 415         struct ipv6_fl_socklist *sfl1=NULL;
 416         struct ipv6_fl_socklist *sfl, **sflp;
 417         struct ip6_flowlabel *fl;
 418
 419         if (optlen < sizeof(freq))
 420                 return -EINVAL;
 421
 422         if (copy_from_user(&freq, optval, sizeof(freq)))
 423                 return -EFAULT;
 424
 425         switch (freq.flr_action) {
 426         case IPV6_FL_A_PUT:
 427                 write_lock_bh(&ip6_sk_fl_lock);
 428                 for (sflp = &np->ipv6_fl_list; (sfl=*sflp)!=NULL; sflp = &sfl->next) {
 429                         if (sfl->fl->label == freq.flr_label) {
 430                                 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
 431                                         np->flow_label &= ~IPV6_FLOWLABEL_MASK;
 432                                 *sflp = sfl->next;
 433                                 write_unlock_bh(&ip6_sk_fl_lock);
 434                                 fl_release(sfl->fl);
 435                                 kfree(sfl);
 436                                 return 0;
 437                         }
 438                 }
 439                 write_unlock_bh(&ip6_sk_fl_lock);
 440                 return -ESRCH;
 441
 442         case IPV6_FL_A_RENEW:
 443                 read_lock_bh(&ip6_sk_fl_lock);
 444                 for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
 445                         if (sfl->fl->label == freq.flr_label) {
 446                                 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
 447                                 read_unlock_bh(&ip6_sk_fl_lock);
 448                                 return err;
 449                         }
 450                 }
 451                 read_unlock_bh(&ip6_sk_fl_lock);
 452
 453                 if (freq.flr_share == IPV6_FL_S_NONE && capable(CAP_NET_ADMIN)) {
 454                         fl = fl_lookup(freq.flr_label);
 455                         if (fl) {
 456                                 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
 457                                 fl_release(fl);
 458                                 return err;
 459                         }
 460                 }
 461                 return -ESRCH;
 462
 463         case IPV6_FL_A_GET:
 464                 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
 465                         return -EINVAL;
 466
 467                 fl = fl_create(&freq, optval, optlen, &err);
 468                 if (fl == NULL)
 469                         return err;
 470                 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
 471
 472                 if (freq.flr_label) {
 473                         struct ip6_flowlabel *fl1 = NULL;
 474
 475                         err = -EEXIST;
 476                         read_lock_bh(&ip6_sk_fl_lock);
 477                         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
 478                                 if (sfl->fl->label == freq.flr_label) {
 479                                         if (freq.flr_flags&IPV6_FL_F_EXCL) {
 480                                                 read_unlock_bh(&ip6_sk_fl_lock);
 481                                                 goto done;
 482                                         }
 483                                         fl1 = sfl->fl;
 484                                         atomic_inc(&fl1->users);
 485                                         break;
 486                                 }
 487                         }
 488                         read_unlock_bh(&ip6_sk_fl_lock);
 489
 490                         if (fl1 == NULL)
 491                                 fl1 = fl_lookup(freq.flr_label);
 492                         if (fl1) {
 493                                 err = -EEXIST;
 494                                 if (freq.flr_flags&IPV6_FL_F_EXCL)
 495                                         goto release;
 496                                 err = -EPERM;
 497                                 if (fl1->share == IPV6_FL_S_EXCL ||
 498                                     fl1->share != fl->share ||
 499                                     fl1->owner != fl->owner)
 500                                         goto release;
 501
 502                                 err = -EINVAL;
 503                                 if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
 504                                     ipv6_opt_cmp(fl1->opt, fl->opt))
 505                                         goto release;
 506
 507                                 err = -ENOMEM;
 508                                 if (sfl1 == NULL)
 509                                         goto release;
 510                                 if (fl->linger > fl1->linger)
 511                                         fl1->linger = fl->linger;
 512                                 if ((long)(fl->expires - fl1->expires) > 0)
 513                                         fl1->expires = fl->expires;
 514                                 write_lock_bh(&ip6_sk_fl_lock);
 515                                 sfl1->fl = fl1;
 516                                 sfl1->next = np->ipv6_fl_list;
 517                                 np->ipv6_fl_list = sfl1;
 518                                 write_unlock_bh(&ip6_sk_fl_lock);
 519                                 fl_free(fl);
 520                                 return 0;
 521
 522 release:
 523                                 fl_release(fl1);
 524                                 goto done;
 525                         }
 526                 }
 527                 err = -ENOENT;
 528                 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
 529                         goto done;
 530
 531                 err = -ENOMEM;
 532                 if (sfl1 == NULL || (err = mem_check(sk)) != 0)
 533                         goto done;
 534
 535                 err = fl_intern(fl, freq.flr_label);
 536                 if (err)
 537                         goto done;
 538
 539                 if (!freq.flr_label) {
 540                         if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
 541                                          &fl->label, sizeof(fl->label))) {
 542                                 /* Intentionally ignore fault. */
 543                         }
 544                 }
 545
 546                 sfl1->fl = fl;
 547                 sfl1->next = np->ipv6_fl_list;
 548                 np->ipv6_fl_list = sfl1;
 549                 return 0;
 550
 551         default:
 552                 return -EINVAL;
 553         }
 554
 555 done:
 556         fl_free(fl);
 557         kfree(sfl1);
 558         return err;
 559 }
 560
 561 #ifdef CONFIG_PROC_FS
 562
 563 struct ip6fl_iter_state {
 564         int bucket;
 565 };
 566
 567 #define ip6fl_seq_private(seq)  ((struct ip6fl_iter_state *)(seq)->private)
 568
 569 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
 570 {
 571         struct ip6_flowlabel *fl = NULL;
 572         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
 573
 574         for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
 575                 if (fl_ht[state->bucket]) {
 576                         fl = fl_ht[state->bucket];
 577                         break;
 578                 }
 579         }
 580         return fl;
 581 }
 582
 583 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
 584 {
 585         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
 586
 587         fl = fl->next;
 588         while (!fl) {
 589                 if (++state->bucket <= FL_HASH_MASK)
 590                         fl = fl_ht[state->bucket];
 591         }
 592         return fl;
 593 }
 594
 595 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
 596 {
 597         struct ip6_flowlabel *fl = ip6fl_get_first(seq);
 598         if (fl)
 599                 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
 600                         --pos;
 601         return pos ? NULL : fl;
 602 }
 603
 604 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
 605 {
 606         read_lock_bh(&ip6_fl_lock);
 607         return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
 608 }
 609
 610 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 611 {
 612         struct ip6_flowlabel *fl;
 613
 614         if (v == SEQ_START_TOKEN)
 615                 fl = ip6fl_get_first(seq);
 616         else
 617                 fl = ip6fl_get_next(seq, v);
 618         ++*pos;
 619         return fl;
 620 }
 621
 622 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
 623 {
 624         read_unlock_bh(&ip6_fl_lock);
 625 }
 626
 627 static void ip6fl_fl_seq_show(struct seq_file *seq, struct ip6_flowlabel *fl)
 628 {
 629         while(fl) {
 630                 seq_printf(seq,
 631                            "%05X %-1d %-6d %-6d %-6ld %-8ld "
 632                            "%02x%02x%02x%02x%02x%02x%02x%02x "
 633                            "%-4d\n",
 634                            (unsigned)ntohl(fl->label),
 635                            fl->share,
 636                            (unsigned)fl->owner,
 637                            atomic_read(&fl->users),
 638                            fl->linger/HZ,
 639                            (long)(fl->expires - jiffies)/HZ,
 640                            NIP6(fl->dst),
 641                            fl->opt ? fl->opt->opt_nflen : 0);
 642                 fl = fl->next;
 643         }
 644 }
 645
 646 static int ip6fl_seq_show(struct seq_file *seq, void *v)
 647 {
 648         if (v == SEQ_START_TOKEN)
 649                 seq_puts(seq, "Label S Owner  Users  Linger Expires  "
 650                               "Dst                              Opt\n");
 651         else
 652                 ip6fl_fl_seq_show(seq, v);
 653         return 0;
 654 }
 655
 656 static struct seq_operations ip6fl_seq_ops = {
 657         .start  =       ip6fl_seq_start,
 658         .next   =       ip6fl_seq_next,
 659         .stop   =       ip6fl_seq_stop,
 660         .show   =       ip6fl_seq_show,
 661 };
 662
 663 static int ip6fl_seq_open(struct inode *inode, struct file *file)
 664 {
 665         struct seq_file *seq;
 666         int rc = -ENOMEM;
 667         struct ip6fl_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
 668
 669         if (!s)
 670                 goto out;
 671
 672         rc = seq_open(file, &ip6fl_seq_ops);
 673         if (rc)
 674                 goto out_kfree;
 675
 676         seq = file->private_data;
 677         seq->private = s;
 678         memset(s, 0, sizeof(*s));
 679 out:
 680         return rc;
 681 out_kfree:
 682         kfree(s);
 683         goto out;
 684 }
 685
 686 static struct file_operations ip6fl_seq_fops = {
 687         .owner          =       THIS_MODULE,
 688         .open           =       ip6fl_seq_open,
 689         .read           =       seq_read,
 690         .llseek         =       seq_lseek,
 691         .release        =       seq_release_private,
 692 };
 693 #endif
 694
 695
 696 void ip6_flowlabel_init(void)
 697 {
 698 #ifdef CONFIG_PROC_FS
 699         proc_net_fops_create("ip6_flowlabel", S_IRUGO, &ip6fl_seq_fops);
 700 #endif
 701 }
 702
 703 void ip6_flowlabel_cleanup(void)
 704 {
 705         del_timer(&ip6_fl_gc_timer);
 706 #ifdef CONFIG_PROC_FS
 707         proc_net_remove("ip6_flowlabel");
 708 #endif
 709 }