Pileus Git - ~andy/linux/blob - net/atm/clip.c

   1 /* net/atm/clip.c - RFC1577 Classical IP over ATM */
   2
   3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   4
   5 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
   6
   7 #include <linux/string.h>
   8 #include <linux/errno.h>
   9 #include <linux/kernel.h> /* for UINT_MAX */
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/wait.h>
  15 #include <linux/timer.h>
  16 #include <linux/if_arp.h> /* for some manifest constants */
  17 #include <linux/notifier.h>
  18 #include <linux/atm.h>
  19 #include <linux/atmdev.h>
  20 #include <linux/atmclip.h>
  21 #include <linux/atmarp.h>
  22 #include <linux/capability.h>
  23 #include <linux/ip.h> /* for net/route.h */
  24 #include <linux/in.h> /* for struct sockaddr_in */
  25 #include <linux/if.h> /* for IFF_UP */
  26 #include <linux/inetdevice.h>
  27 #include <linux/bitops.h>
  28 #include <linux/poison.h>
  29 #include <linux/proc_fs.h>
  30 #include <linux/seq_file.h>
  31 #include <linux/rcupdate.h>
  32 #include <linux/jhash.h>
  33 #include <linux/slab.h>
  34 #include <net/route.h> /* for struct rtable and routing */
  35 #include <net/icmp.h> /* icmp_send */
  36 #include <linux/param.h> /* for HZ */
  37 #include <linux/uaccess.h>
  38 #include <asm/byteorder.h> /* for htons etc. */
  39 #include <asm/system.h> /* save/restore_flags */
  40 #include <asm/atomic.h>
  41
  42 #include "common.h"
  43 #include "resources.h"
  44 #include <net/atmclip.h>
  45
  46 static struct net_device *clip_devs;
  47 static struct atm_vcc *atmarpd;
  48 static struct neigh_table clip_tbl;
  49 static struct timer_list idle_timer;
  50
  51 static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip)
  52 {
  53         struct sock *sk;
  54         struct atmarp_ctrl *ctrl;
  55         struct sk_buff *skb;
  56
  57         pr_debug("(%d)\n", type);
  58         if (!atmarpd)
  59                 return -EUNATCH;
  60         skb = alloc_skb(sizeof(struct atmarp_ctrl), GFP_ATOMIC);
  61         if (!skb)
  62                 return -ENOMEM;
  63         ctrl = (struct atmarp_ctrl *)skb_put(skb, sizeof(struct atmarp_ctrl));
  64         ctrl->type = type;
  65         ctrl->itf_num = itf;
  66         ctrl->ip = ip;
  67         atm_force_charge(atmarpd, skb->truesize);
  68
  69         sk = sk_atm(atmarpd);
  70         skb_queue_tail(&sk->sk_receive_queue, skb);
  71         sk->sk_data_ready(sk, skb->len);
  72         return 0;
  73 }
  74
  75 static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry)
  76 {
  77         pr_debug("%p to entry %p (neigh %p)\n", clip_vcc, entry, entry->neigh);
  78         clip_vcc->entry = entry;
  79         clip_vcc->xoff = 0;     /* @@@ may overrun buffer by one packet */
  80         clip_vcc->next = entry->vccs;
  81         entry->vccs = clip_vcc;
  82         entry->neigh->used = jiffies;
  83 }
  84
  85 static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
  86 {
  87         struct atmarp_entry *entry = clip_vcc->entry;
  88         struct clip_vcc **walk;
  89
  90         if (!entry) {
  91                 pr_crit("!clip_vcc->entry (clip_vcc %p)\n", clip_vcc);
  92                 return;
  93         }
  94         netif_tx_lock_bh(entry->neigh->dev);    /* block clip_start_xmit() */
  95         entry->neigh->used = jiffies;
  96         for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
  97                 if (*walk == clip_vcc) {
  98                         int error;
  99
 100                         *walk = clip_vcc->next; /* atomic */
 101                         clip_vcc->entry = NULL;
 102                         if (clip_vcc->xoff)
 103                                 netif_wake_queue(entry->neigh->dev);
 104                         if (entry->vccs)
 105                                 goto out;
 106                         entry->expires = jiffies - 1;
 107                         /* force resolution or expiration */
 108                         error = neigh_update(entry->neigh, NULL, NUD_NONE,
 109                                              NEIGH_UPDATE_F_ADMIN);
 110                         if (error)
 111                                 pr_crit("neigh_update failed with %d\n", error);
 112                         goto out;
 113                 }
 114         pr_crit("ATMARP: failed (entry %p, vcc 0x%p)\n", entry, clip_vcc);
 115 out:
 116         netif_tx_unlock_bh(entry->neigh->dev);
 117 }
 118
 119 /* The neighbour entry n->lock is held. */
 120 static int neigh_check_cb(struct neighbour *n)
 121 {
 122         struct atmarp_entry *entry = NEIGH2ENTRY(n);
 123         struct clip_vcc *cv;
 124
 125         for (cv = entry->vccs; cv; cv = cv->next) {
 126                 unsigned long exp = cv->last_use + cv->idle_timeout;
 127
 128                 if (cv->idle_timeout && time_after(jiffies, exp)) {
 129                         pr_debug("releasing vcc %p->%p of entry %p\n",
 130                                  cv, cv->vcc, entry);
 131                         vcc_release_async(cv->vcc, -ETIMEDOUT);
 132                 }
 133         }
 134
 135         if (entry->vccs || time_before(jiffies, entry->expires))
 136                 return 0;
 137
 138         if (atomic_read(&n->refcnt) > 1) {
 139                 struct sk_buff *skb;
 140
 141                 pr_debug("destruction postponed with ref %d\n",
 142                          atomic_read(&n->refcnt));
 143
 144                 while ((skb = skb_dequeue(&n->arp_queue)) != NULL)
 145                         dev_kfree_skb(skb);
 146
 147                 return 0;
 148         }
 149
 150         pr_debug("expired neigh %p\n", n);
 151         return 1;
 152 }
 153
 154 static void idle_timer_check(unsigned long dummy)
 155 {
 156         write_lock(&clip_tbl.lock);
 157         __neigh_for_each_release(&clip_tbl, neigh_check_cb);
 158         mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
 159         write_unlock(&clip_tbl.lock);
 160 }
 161
 162 static int clip_arp_rcv(struct sk_buff *skb)
 163 {
 164         struct atm_vcc *vcc;
 165
 166         pr_debug("\n");
 167         vcc = ATM_SKB(skb)->vcc;
 168         if (!vcc || !atm_charge(vcc, skb->truesize)) {
 169                 dev_kfree_skb_any(skb);
 170                 return 0;
 171         }
 172         pr_debug("pushing to %p\n", vcc);
 173         pr_debug("using %p\n", CLIP_VCC(vcc)->old_push);
 174         CLIP_VCC(vcc)->old_push(vcc, skb);
 175         return 0;
 176 }
 177
 178 static const unsigned char llc_oui[] = {
 179         0xaa,   /* DSAP: non-ISO */
 180         0xaa,   /* SSAP: non-ISO */
 181         0x03,   /* Ctrl: Unnumbered Information Command PDU */
 182         0x00,   /* OUI: EtherType */
 183         0x00,
 184         0x00
 185 };
 186
 187 static void clip_push(struct atm_vcc *vcc, struct sk_buff *skb)
 188 {
 189         struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
 190
 191         pr_debug("\n");
 192         if (!skb) {
 193                 pr_debug("removing VCC %p\n", clip_vcc);
 194                 if (clip_vcc->entry)
 195                         unlink_clip_vcc(clip_vcc);
 196                 clip_vcc->old_push(vcc, NULL);  /* pass on the bad news */
 197                 kfree(clip_vcc);
 198                 return;
 199         }
 200         atm_return(vcc, skb->truesize);
 201         skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
 202         /* clip_vcc->entry == NULL if we don't have an IP address yet */
 203         if (!skb->dev) {
 204                 dev_kfree_skb_any(skb);
 205                 return;
 206         }
 207         ATM_SKB(skb)->vcc = vcc;
 208         skb_reset_mac_header(skb);
 209         if (!clip_vcc->encap ||
 210             skb->len < RFC1483LLC_LEN ||
 211             memcmp(skb->data, llc_oui, sizeof(llc_oui)))
 212                 skb->protocol = htons(ETH_P_IP);
 213         else {
 214                 skb->protocol = ((__be16 *)skb->data)[3];
 215                 skb_pull(skb, RFC1483LLC_LEN);
 216                 if (skb->protocol == htons(ETH_P_ARP)) {
 217                         skb->dev->stats.rx_packets++;
 218                         skb->dev->stats.rx_bytes += skb->len;
 219                         clip_arp_rcv(skb);
 220                         return;
 221                 }
 222         }
 223         clip_vcc->last_use = jiffies;
 224         skb->dev->stats.rx_packets++;
 225         skb->dev->stats.rx_bytes += skb->len;
 226         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
 227         netif_rx(skb);
 228 }
 229
 230 /*
 231  * Note: these spinlocks _must_not_ block on non-SMP. The only goal is that
 232  * clip_pop is atomic with respect to the critical section in clip_start_xmit.
 233  */
 234
 235 static void clip_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 236 {
 237         struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
 238         struct net_device *dev = skb->dev;
 239         int old;
 240         unsigned long flags;
 241
 242         pr_debug("(vcc %p)\n", vcc);
 243         clip_vcc->old_pop(vcc, skb);
 244         /* skb->dev == NULL in outbound ARP packets */
 245         if (!dev)
 246                 return;
 247         spin_lock_irqsave(&PRIV(dev)->xoff_lock, flags);
 248         if (atm_may_send(vcc, 0)) {
 249                 old = xchg(&clip_vcc->xoff, 0);
 250                 if (old)
 251                         netif_wake_queue(dev);
 252         }
 253         spin_unlock_irqrestore(&PRIV(dev)->xoff_lock, flags);
 254 }
 255
 256 static void clip_neigh_solicit(struct neighbour *neigh, struct sk_buff *skb)
 257 {
 258         pr_debug("(neigh %p, skb %p)\n", neigh, skb);
 259         to_atmarpd(act_need, PRIV(neigh->dev)->number, NEIGH2ENTRY(neigh)->ip);
 260 }
 261
 262 static void clip_neigh_error(struct neighbour *neigh, struct sk_buff *skb)
 263 {
 264 #ifndef CONFIG_ATM_CLIP_NO_ICMP
 265         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
 266 #endif
 267         kfree_skb(skb);
 268 }
 269
 270 static const struct neigh_ops clip_neigh_ops = {
 271         .family =               AF_INET,
 272         .solicit =              clip_neigh_solicit,
 273         .error_report =         clip_neigh_error,
 274         .output =               dev_queue_xmit,
 275         .connected_output =     dev_queue_xmit,
 276 };
 277
 278 static int clip_constructor(struct neighbour *neigh)
 279 {
 280         struct atmarp_entry *entry = NEIGH2ENTRY(neigh);
 281         struct net_device *dev = neigh->dev;
 282         struct in_device *in_dev;
 283         struct neigh_parms *parms;
 284
 285         pr_debug("(neigh %p, entry %p)\n", neigh, entry);
 286         neigh->type = inet_addr_type(&init_net, entry->ip);
 287         if (neigh->type != RTN_UNICAST)
 288                 return -EINVAL;
 289
 290         rcu_read_lock();
 291         in_dev = __in_dev_get_rcu(dev);
 292         if (!in_dev) {
 293                 rcu_read_unlock();
 294                 return -EINVAL;
 295         }
 296
 297         parms = in_dev->arp_parms;
 298         __neigh_parms_put(neigh->parms);
 299         neigh->parms = neigh_parms_clone(parms);
 300         rcu_read_unlock();
 301
 302         neigh->ops = &clip_neigh_ops;
 303         neigh->output = neigh->nud_state & NUD_VALID ?
 304             neigh->ops->connected_output : neigh->ops->output;
 305         entry->neigh = neigh;
 306         entry->vccs = NULL;
 307         entry->expires = jiffies - 1;
 308         return 0;
 309 }
 310
 311 static u32 clip_hash(const void *pkey, const struct net_device *dev, __u32 rnd)
 312 {
 313         return jhash_2words(*(u32 *) pkey, dev->ifindex, rnd);
 314 }
 315
 316 static struct neigh_table clip_tbl = {
 317         .family         = AF_INET,
 318         .entry_size     = sizeof(struct neighbour)+sizeof(struct atmarp_entry),
 319         .key_len        = 4,
 320         .hash           = clip_hash,
 321         .constructor    = clip_constructor,
 322         .id             = "clip_arp_cache",
 323
 324         /* parameters are copied from ARP ... */
 325         .parms = {
 326                 .tbl                    = &clip_tbl,
 327                 .base_reachable_time    = 30 * HZ,
 328                 .retrans_time           = 1 * HZ,
 329                 .gc_staletime           = 60 * HZ,
 330                 .reachable_time         = 30 * HZ,
 331                 .delay_probe_time       = 5 * HZ,
 332                 .queue_len              = 3,
 333                 .ucast_probes           = 3,
 334                 .mcast_probes           = 3,
 335                 .anycast_delay          = 1 * HZ,
 336                 .proxy_delay            = (8 * HZ) / 10,
 337                 .proxy_qlen             = 64,
 338                 .locktime               = 1 * HZ,
 339         },
 340         .gc_interval    = 30 * HZ,
 341         .gc_thresh1     = 128,
 342         .gc_thresh2     = 512,
 343         .gc_thresh3     = 1024,
 344 };
 345
 346 /* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
 347
 348 /*
 349  * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
 350  * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
 351  * don't increment the usage count. This is used to create entries in
 352  * clip_setentry.
 353  */
 354
 355 static int clip_encap(struct atm_vcc *vcc, int mode)
 356 {
 357         CLIP_VCC(vcc)->encap = mode;
 358         return 0;
 359 }
 360
 361 static netdev_tx_t clip_start_xmit(struct sk_buff *skb,
 362                                    struct net_device *dev)
 363 {
 364         struct clip_priv *clip_priv = PRIV(dev);
 365         struct atmarp_entry *entry;
 366         struct atm_vcc *vcc;
 367         int old;
 368         unsigned long flags;
 369
 370         pr_debug("(skb %p)\n", skb);
 371         if (!skb_dst(skb)) {
 372                 pr_err("skb_dst(skb) == NULL\n");
 373                 dev_kfree_skb(skb);
 374                 dev->stats.tx_dropped++;
 375                 return NETDEV_TX_OK;
 376         }
 377         if (!skb_dst(skb)->neighbour) {
 378 #if 0
 379                 skb_dst(skb)->neighbour = clip_find_neighbour(skb_dst(skb), 1);
 380                 if (!skb_dst(skb)->neighbour) {
 381                         dev_kfree_skb(skb);     /* lost that one */
 382                         dev->stats.tx_dropped++;
 383                         return 0;
 384                 }
 385 #endif
 386                 pr_err("NO NEIGHBOUR !\n");
 387                 dev_kfree_skb(skb);
 388                 dev->stats.tx_dropped++;
 389                 return NETDEV_TX_OK;
 390         }
 391         entry = NEIGH2ENTRY(skb_dst(skb)->neighbour);
 392         if (!entry->vccs) {
 393                 if (time_after(jiffies, entry->expires)) {
 394                         /* should be resolved */
 395                         entry->expires = jiffies + ATMARP_RETRY_DELAY * HZ;
 396                         to_atmarpd(act_need, PRIV(dev)->number, entry->ip);
 397                 }
 398                 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
 399                         skb_queue_tail(&entry->neigh->arp_queue, skb);
 400                 else {
 401                         dev_kfree_skb(skb);
 402                         dev->stats.tx_dropped++;
 403                 }
 404                 return NETDEV_TX_OK;
 405         }
 406         pr_debug("neigh %p, vccs %p\n", entry, entry->vccs);
 407         ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
 408         pr_debug("using neighbour %p, vcc %p\n", skb_dst(skb)->neighbour, vcc);
 409         if (entry->vccs->encap) {
 410                 void *here;
 411
 412                 here = skb_push(skb, RFC1483LLC_LEN);
 413                 memcpy(here, llc_oui, sizeof(llc_oui));
 414                 ((__be16 *) here)[3] = skb->protocol;
 415         }
 416         atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
 417         ATM_SKB(skb)->atm_options = vcc->atm_options;
 418         entry->vccs->last_use = jiffies;
 419         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, vcc, vcc->dev);
 420         old = xchg(&entry->vccs->xoff, 1);      /* assume XOFF ... */
 421         if (old) {
 422                 pr_warning("XOFF->XOFF transition\n");
 423                 return NETDEV_TX_OK;
 424         }
 425         dev->stats.tx_packets++;
 426         dev->stats.tx_bytes += skb->len;
 427         vcc->send(vcc, skb);
 428         if (atm_may_send(vcc, 0)) {
 429                 entry->vccs->xoff = 0;
 430                 return NETDEV_TX_OK;
 431         }
 432         spin_lock_irqsave(&clip_priv->xoff_lock, flags);
 433         netif_stop_queue(dev);  /* XOFF -> throttle immediately */
 434         barrier();
 435         if (!entry->vccs->xoff)
 436                 netif_start_queue(dev);
 437         /* Oh, we just raced with clip_pop. netif_start_queue should be
 438            good enough, because nothing should really be asleep because
 439            of the brief netif_stop_queue. If this isn't true or if it
 440            changes, use netif_wake_queue instead. */
 441         spin_unlock_irqrestore(&clip_priv->xoff_lock, flags);
 442         return NETDEV_TX_OK;
 443 }
 444
 445 static int clip_mkip(struct atm_vcc *vcc, int timeout)
 446 {
 447         struct sk_buff_head *rq, queue;
 448         struct clip_vcc *clip_vcc;
 449         struct sk_buff *skb, *tmp;
 450         unsigned long flags;
 451
 452         if (!vcc->push)
 453                 return -EBADFD;
 454         clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL);
 455         if (!clip_vcc)
 456                 return -ENOMEM;
 457         pr_debug("%p vcc %p\n", clip_vcc, vcc);
 458         clip_vcc->vcc = vcc;
 459         vcc->user_back = clip_vcc;
 460         set_bit(ATM_VF_IS_CLIP, &vcc->flags);
 461         clip_vcc->entry = NULL;
 462         clip_vcc->xoff = 0;
 463         clip_vcc->encap = 1;
 464         clip_vcc->last_use = jiffies;
 465         clip_vcc->idle_timeout = timeout * HZ;
 466         clip_vcc->old_push = vcc->push;
 467         clip_vcc->old_pop = vcc->pop;
 468         vcc->push = clip_push;
 469         vcc->pop = clip_pop;
 470
 471         __skb_queue_head_init(&queue);
 472         rq = &sk_atm(vcc)->sk_receive_queue;
 473
 474         spin_lock_irqsave(&rq->lock, flags);
 475         skb_queue_splice_init(rq, &queue);
 476         spin_unlock_irqrestore(&rq->lock, flags);
 477
 478         /* re-process everything received between connection setup and MKIP */
 479         skb_queue_walk_safe(&queue, skb, tmp) {
 480                 if (!clip_devs) {
 481                         atm_return(vcc, skb->truesize);
 482                         kfree_skb(skb);
 483                 } else {
 484                         struct net_device *dev = skb->dev;
 485                         unsigned int len = skb->len;
 486
 487                         skb_get(skb);
 488                         clip_push(vcc, skb);
 489                         dev->stats.rx_packets--;
 490                         dev->stats.rx_bytes -= len;
 491                         kfree_skb(skb);
 492                 }
 493         }
 494         return 0;
 495 }
 496
 497 static int clip_setentry(struct atm_vcc *vcc, __be32 ip)
 498 {
 499         struct neighbour *neigh;
 500         struct atmarp_entry *entry;
 501         int error;
 502         struct clip_vcc *clip_vcc;
 503         struct rtable *rt;
 504
 505         if (vcc->push != clip_push) {
 506                 pr_warning("non-CLIP VCC\n");
 507                 return -EBADF;
 508         }
 509         clip_vcc = CLIP_VCC(vcc);
 510         if (!ip) {
 511                 if (!clip_vcc->entry) {
 512                         pr_err("hiding hidden ATMARP entry\n");
 513                         return 0;
 514                 }
 515                 pr_debug("remove\n");
 516                 unlink_clip_vcc(clip_vcc);
 517                 return 0;
 518         }
 519         rt = ip_route_output(&init_net, ip, 0, 1, 0);
 520         if (IS_ERR(rt))
 521                 return PTR_ERR(rt);
 522         neigh = __neigh_lookup(&clip_tbl, &ip, rt->dst.dev, 1);
 523         ip_rt_put(rt);
 524         if (!neigh)
 525                 return -ENOMEM;
 526         entry = NEIGH2ENTRY(neigh);
 527         if (entry != clip_vcc->entry) {
 528                 if (!clip_vcc->entry)
 529                         pr_debug("add\n");
 530                 else {
 531                         pr_debug("update\n");
 532                         unlink_clip_vcc(clip_vcc);
 533                 }
 534                 link_vcc(clip_vcc, entry);
 535         }
 536         error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
 537                              NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN);
 538         neigh_release(neigh);
 539         return error;
 540 }
 541
 542 static const struct net_device_ops clip_netdev_ops = {
 543         .ndo_start_xmit = clip_start_xmit,
 544 };
 545
 546 static void clip_setup(struct net_device *dev)
 547 {
 548         dev->netdev_ops = &clip_netdev_ops;
 549         dev->type = ARPHRD_ATM;
 550         dev->hard_header_len = RFC1483LLC_LEN;
 551         dev->mtu = RFC1626_MTU;
 552         dev->tx_queue_len = 100;        /* "normal" queue (packets) */
 553         /* When using a "real" qdisc, the qdisc determines the queue */
 554         /* length. tx_queue_len is only used for the default case, */
 555         /* without any more elaborate queuing. 100 is a reasonable */
 556         /* compromise between decent burst-tolerance and protection */
 557         /* against memory hogs. */
 558         dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
 559 }
 560
 561 static int clip_create(int number)
 562 {
 563         struct net_device *dev;
 564         struct clip_priv *clip_priv;
 565         int error;
 566
 567         if (number != -1) {
 568                 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
 569                         if (PRIV(dev)->number == number)
 570                                 return -EEXIST;
 571         } else {
 572                 number = 0;
 573                 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
 574                         if (PRIV(dev)->number >= number)
 575                                 number = PRIV(dev)->number + 1;
 576         }
 577         dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
 578         if (!dev)
 579                 return -ENOMEM;
 580         clip_priv = PRIV(dev);
 581         sprintf(dev->name, "atm%d", number);
 582         spin_lock_init(&clip_priv->xoff_lock);
 583         clip_priv->number = number;
 584         error = register_netdev(dev);
 585         if (error) {
 586                 free_netdev(dev);
 587                 return error;
 588         }
 589         clip_priv->next = clip_devs;
 590         clip_devs = dev;
 591         pr_debug("registered (net:%s)\n", dev->name);
 592         return number;
 593 }
 594
 595 static int clip_device_event(struct notifier_block *this, unsigned long event,
 596                              void *arg)
 597 {
 598         struct net_device *dev = arg;
 599
 600         if (!net_eq(dev_net(dev), &init_net))
 601                 return NOTIFY_DONE;
 602
 603         if (event == NETDEV_UNREGISTER) {
 604                 neigh_ifdown(&clip_tbl, dev);
 605                 return NOTIFY_DONE;
 606         }
 607
 608         /* ignore non-CLIP devices */
 609         if (dev->type != ARPHRD_ATM || dev->netdev_ops != &clip_netdev_ops)
 610                 return NOTIFY_DONE;
 611
 612         switch (event) {
 613         case NETDEV_UP:
 614                 pr_debug("NETDEV_UP\n");
 615                 to_atmarpd(act_up, PRIV(dev)->number, 0);
 616                 break;
 617         case NETDEV_GOING_DOWN:
 618                 pr_debug("NETDEV_DOWN\n");
 619                 to_atmarpd(act_down, PRIV(dev)->number, 0);
 620                 break;
 621         case NETDEV_CHANGE:
 622         case NETDEV_CHANGEMTU:
 623                 pr_debug("NETDEV_CHANGE*\n");
 624                 to_atmarpd(act_change, PRIV(dev)->number, 0);
 625                 break;
 626         }
 627         return NOTIFY_DONE;
 628 }
 629
 630 static int clip_inet_event(struct notifier_block *this, unsigned long event,
 631                            void *ifa)
 632 {
 633         struct in_device *in_dev;
 634
 635         in_dev = ((struct in_ifaddr *)ifa)->ifa_dev;
 636         /*
 637          * Transitions are of the down-change-up type, so it's sufficient to
 638          * handle the change on up.
 639          */
 640         if (event != NETDEV_UP)
 641                 return NOTIFY_DONE;
 642         return clip_device_event(this, NETDEV_CHANGE, in_dev->dev);
 643 }
 644
 645 static struct notifier_block clip_dev_notifier = {
 646         .notifier_call = clip_device_event,
 647 };
 648
 649
 650
 651 static struct notifier_block clip_inet_notifier = {
 652         .notifier_call = clip_inet_event,
 653 };
 654
 655
 656
 657 static void atmarpd_close(struct atm_vcc *vcc)
 658 {
 659         pr_debug("\n");
 660
 661         rtnl_lock();
 662         atmarpd = NULL;
 663         skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
 664         rtnl_unlock();
 665
 666         pr_debug("(done)\n");
 667         module_put(THIS_MODULE);
 668 }
 669
 670 static struct atmdev_ops atmarpd_dev_ops = {
 671         .close = atmarpd_close
 672 };
 673
 674
 675 static struct atm_dev atmarpd_dev = {
 676         .ops =                  &atmarpd_dev_ops,
 677         .type =                 "arpd",
 678         .number =               999,
 679         .lock =                 __SPIN_LOCK_UNLOCKED(atmarpd_dev.lock)
 680 };
 681
 682
 683 static int atm_init_atmarp(struct atm_vcc *vcc)
 684 {
 685         rtnl_lock();
 686         if (atmarpd) {
 687                 rtnl_unlock();
 688                 return -EADDRINUSE;
 689         }
 690
 691         mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
 692
 693         atmarpd = vcc;
 694         set_bit(ATM_VF_META, &vcc->flags);
 695         set_bit(ATM_VF_READY, &vcc->flags);
 696             /* allow replies and avoid getting closed if signaling dies */
 697         vcc->dev = &atmarpd_dev;
 698         vcc_insert_socket(sk_atm(vcc));
 699         vcc->push = NULL;
 700         vcc->pop = NULL; /* crash */
 701         vcc->push_oam = NULL; /* crash */
 702         rtnl_unlock();
 703         return 0;
 704 }
 705
 706 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 707 {
 708         struct atm_vcc *vcc = ATM_SD(sock);
 709         int err = 0;
 710
 711         switch (cmd) {
 712         case SIOCMKCLIP:
 713         case ATMARPD_CTRL:
 714         case ATMARP_MKIP:
 715         case ATMARP_SETENTRY:
 716         case ATMARP_ENCAP:
 717                 if (!capable(CAP_NET_ADMIN))
 718                         return -EPERM;
 719                 break;
 720         default:
 721                 return -ENOIOCTLCMD;
 722         }
 723
 724         switch (cmd) {
 725         case SIOCMKCLIP:
 726                 err = clip_create(arg);
 727                 break;
 728         case ATMARPD_CTRL:
 729                 err = atm_init_atmarp(vcc);
 730                 if (!err) {
 731                         sock->state = SS_CONNECTED;
 732                         __module_get(THIS_MODULE);
 733                 }
 734                 break;
 735         case ATMARP_MKIP:
 736                 err = clip_mkip(vcc, arg);
 737                 break;
 738         case ATMARP_SETENTRY:
 739                 err = clip_setentry(vcc, (__force __be32)arg);
 740                 break;
 741         case ATMARP_ENCAP:
 742                 err = clip_encap(vcc, arg);
 743                 break;
 744         }
 745         return err;
 746 }
 747
 748 static struct atm_ioctl clip_ioctl_ops = {
 749         .owner = THIS_MODULE,
 750         .ioctl = clip_ioctl,
 751 };
 752
 753 #ifdef CONFIG_PROC_FS
 754
 755 static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
 756 {
 757         static int code[] = { 1, 2, 10, 6, 1, 0 };
 758         static int e164[] = { 1, 8, 4, 6, 1, 0 };
 759
 760         if (*addr->sas_addr.pub) {
 761                 seq_printf(seq, "%s", addr->sas_addr.pub);
 762                 if (*addr->sas_addr.prv)
 763                         seq_putc(seq, '+');
 764         } else if (!*addr->sas_addr.prv) {
 765                 seq_printf(seq, "%s", "(none)");
 766                 return;
 767         }
 768         if (*addr->sas_addr.prv) {
 769                 unsigned char *prv = addr->sas_addr.prv;
 770                 int *fields;
 771                 int i, j;
 772
 773                 fields = *prv == ATM_AFI_E164 ? e164 : code;
 774                 for (i = 0; fields[i]; i++) {
 775                         for (j = fields[i]; j; j--)
 776                                 seq_printf(seq, "%02X", *prv++);
 777                         if (fields[i + 1])
 778                                 seq_putc(seq, '.');
 779                 }
 780         }
 781 }
 782
 783 /* This means the neighbour entry has no attached VCC objects. */
 784 #define SEQ_NO_VCC_TOKEN        ((void *) 2)
 785
 786 static void atmarp_info(struct seq_file *seq, struct net_device *dev,
 787                         struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
 788 {
 789         unsigned long exp;
 790         char buf[17];
 791         int svc, llc, off;
 792
 793         svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
 794                (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
 795
 796         llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || clip_vcc->encap);
 797
 798         if (clip_vcc == SEQ_NO_VCC_TOKEN)
 799                 exp = entry->neigh->used;
 800         else
 801                 exp = clip_vcc->last_use;
 802
 803         exp = (jiffies - exp) / HZ;
 804
 805         seq_printf(seq, "%-6s%-4s%-4s%5ld ",
 806                    dev->name, svc ? "SVC" : "PVC", llc ? "LLC" : "NULL", exp);
 807
 808         off = scnprintf(buf, sizeof(buf) - 1, "%pI4",
 809                         &entry->ip);
 810         while (off < 16)
 811                 buf[off++] = ' ';
 812         buf[off] = '\0';
 813         seq_printf(seq, "%s", buf);
 814
 815         if (clip_vcc == SEQ_NO_VCC_TOKEN) {
 816                 if (time_before(jiffies, entry->expires))
 817                         seq_printf(seq, "(resolving)\n");
 818                 else
 819                         seq_printf(seq, "(expired, ref %d)\n",
 820                                    atomic_read(&entry->neigh->refcnt));
 821         } else if (!svc) {
 822                 seq_printf(seq, "%d.%d.%d\n",
 823                            clip_vcc->vcc->dev->number,
 824                            clip_vcc->vcc->vpi, clip_vcc->vcc->vci);
 825         } else {
 826                 svc_addr(seq, &clip_vcc->vcc->remote);
 827                 seq_putc(seq, '\n');
 828         }
 829 }
 830
 831 struct clip_seq_state {
 832         /* This member must be first. */
 833         struct neigh_seq_state ns;
 834
 835         /* Local to clip specific iteration. */
 836         struct clip_vcc *vcc;
 837 };
 838
 839 static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
 840                                           struct clip_vcc *curr)
 841 {
 842         if (!curr) {
 843                 curr = e->vccs;
 844                 if (!curr)
 845                         return SEQ_NO_VCC_TOKEN;
 846                 return curr;
 847         }
 848         if (curr == SEQ_NO_VCC_TOKEN)
 849                 return NULL;
 850
 851         curr = curr->next;
 852
 853         return curr;
 854 }
 855
 856 static void *clip_seq_vcc_walk(struct clip_seq_state *state,
 857                                struct atmarp_entry *e, loff_t * pos)
 858 {
 859         struct clip_vcc *vcc = state->vcc;
 860
 861         vcc = clip_seq_next_vcc(e, vcc);
 862         if (vcc && pos != NULL) {
 863                 while (*pos) {
 864                         vcc = clip_seq_next_vcc(e, vcc);
 865                         if (!vcc)
 866                                 break;
 867                         --(*pos);
 868                 }
 869         }
 870         state->vcc = vcc;
 871
 872         return vcc;
 873 }
 874
 875 static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
 876                                struct neighbour *n, loff_t * pos)
 877 {
 878         struct clip_seq_state *state = (struct clip_seq_state *)_state;
 879
 880         return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos);
 881 }
 882
 883 static void *clip_seq_start(struct seq_file *seq, loff_t * pos)
 884 {
 885         struct clip_seq_state *state = seq->private;
 886         state->ns.neigh_sub_iter = clip_seq_sub_iter;
 887         return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY);
 888 }
 889
 890 static int clip_seq_show(struct seq_file *seq, void *v)
 891 {
 892         static char atm_arp_banner[] =
 893             "IPitf TypeEncp Idle IP address      ATM address\n";
 894
 895         if (v == SEQ_START_TOKEN) {
 896                 seq_puts(seq, atm_arp_banner);
 897         } else {
 898                 struct clip_seq_state *state = seq->private;
 899                 struct neighbour *n = v;
 900                 struct clip_vcc *vcc = state->vcc;
 901
 902                 atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
 903         }
 904         return 0;
 905 }
 906
 907 static const struct seq_operations arp_seq_ops = {
 908         .start  = clip_seq_start,
 909         .next   = neigh_seq_next,
 910         .stop   = neigh_seq_stop,
 911         .show   = clip_seq_show,
 912 };
 913
 914 static int arp_seq_open(struct inode *inode, struct file *file)
 915 {
 916         return seq_open_net(inode, file, &arp_seq_ops,
 917                             sizeof(struct clip_seq_state));
 918 }
 919
 920 static const struct file_operations arp_seq_fops = {
 921         .open           = arp_seq_open,
 922         .read           = seq_read,
 923         .llseek         = seq_lseek,
 924         .release        = seq_release_net,
 925         .owner          = THIS_MODULE
 926 };
 927 #endif
 928
 929 static void atm_clip_exit_noproc(void);
 930
 931 static int __init atm_clip_init(void)
 932 {
 933         neigh_table_init_no_netlink(&clip_tbl);
 934
 935         clip_tbl_hook = &clip_tbl;
 936         register_atm_ioctl(&clip_ioctl_ops);
 937         register_netdevice_notifier(&clip_dev_notifier);
 938         register_inetaddr_notifier(&clip_inet_notifier);
 939
 940         setup_timer(&idle_timer, idle_timer_check, 0);
 941
 942 #ifdef CONFIG_PROC_FS
 943         {
 944                 struct proc_dir_entry *p;
 945
 946                 p = proc_create("arp", S_IRUGO, atm_proc_root, &arp_seq_fops);
 947                 if (!p) {
 948                         pr_err("Unable to initialize /proc/net/atm/arp\n");
 949                         atm_clip_exit_noproc();
 950                         return -ENOMEM;
 951                 }
 952         }
 953 #endif
 954
 955         return 0;
 956 }
 957
 958 static void atm_clip_exit_noproc(void)
 959 {
 960         struct net_device *dev, *next;
 961
 962         unregister_inetaddr_notifier(&clip_inet_notifier);
 963         unregister_netdevice_notifier(&clip_dev_notifier);
 964
 965         deregister_atm_ioctl(&clip_ioctl_ops);
 966
 967         /* First, stop the idle timer, so it stops banging
 968          * on the table.
 969          */
 970         del_timer_sync(&idle_timer);
 971
 972         /* Next, purge the table, so that the device
 973          * unregister loop below does not hang due to
 974          * device references remaining in the table.
 975          */
 976         neigh_ifdown(&clip_tbl, NULL);
 977
 978         dev = clip_devs;
 979         while (dev) {
 980                 next = PRIV(dev)->next;
 981                 unregister_netdev(dev);
 982                 free_netdev(dev);
 983                 dev = next;
 984         }
 985
 986         /* Now it is safe to fully shutdown whole table. */
 987         neigh_table_clear(&clip_tbl);
 988
 989         clip_tbl_hook = NULL;
 990 }
 991
 992 static void __exit atm_clip_exit(void)
 993 {
 994         remove_proc_entry("arp", atm_proc_root);
 995
 996         atm_clip_exit_noproc();
 997 }
 998
 999 module_init(atm_clip_init);
1000 module_exit(atm_clip_exit);
1001 MODULE_AUTHOR("Werner Almesberger");
1002 MODULE_DESCRIPTION("Classical/IP over ATM interface");
1003 MODULE_LICENSE("GPL");