err.no Git - linux-2.6/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
   6 #include <linux/config.h>
   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/proc_fs.h>
  29 #include <linux/seq_file.h>
  30 #include <linux/rcupdate.h>
  31 #include <linux/jhash.h>
  32 #include <net/route.h> /* for struct rtable and routing */
  33 #include <net/icmp.h> /* icmp_send */
  34 #include <asm/param.h> /* for HZ */
  35 #include <asm/byteorder.h> /* for htons etc. */
  36 #include <asm/system.h> /* save/restore_flags */
  37 #include <asm/uaccess.h>
  38 #include <asm/atomic.h>
  39
  40 #include "common.h"
  41 #include "resources.h"
  42 #include "ipcommon.h"
  43 #include <net/atmclip.h>
  44
  45
  46 #if 0
  47 #define DPRINTK(format,args...) printk(format,##args)
  48 #else
  49 #define DPRINTK(format,args...)
  50 #endif
  51
  52
  53 static struct net_device *clip_devs;
  54 static struct atm_vcc *atmarpd;
  55 static struct neigh_table clip_tbl;
  56 static struct timer_list idle_timer;
  57
  58 static int to_atmarpd(enum atmarp_ctrl_type type,int itf,unsigned long ip)
  59 {
  60         struct sock *sk;
  61         struct atmarp_ctrl *ctrl;
  62         struct sk_buff *skb;
  63
  64         DPRINTK("to_atmarpd(%d)\n",type);
  65         if (!atmarpd) return -EUNATCH;
  66         skb = alloc_skb(sizeof(struct atmarp_ctrl),GFP_ATOMIC);
  67         if (!skb) return -ENOMEM;
  68         ctrl = (struct atmarp_ctrl *) skb_put(skb,sizeof(struct atmarp_ctrl));
  69         ctrl->type = type;
  70         ctrl->itf_num = itf;
  71         ctrl->ip = ip;
  72         atm_force_charge(atmarpd,skb->truesize);
  73
  74         sk = sk_atm(atmarpd);
  75         skb_queue_tail(&sk->sk_receive_queue, skb);
  76         sk->sk_data_ready(sk, skb->len);
  77         return 0;
  78 }
  79
  80
  81 static void link_vcc(struct clip_vcc *clip_vcc,struct atmarp_entry *entry)
  82 {
  83         DPRINTK("link_vcc %p to entry %p (neigh %p)\n",clip_vcc,entry,
  84             entry->neigh);
  85         clip_vcc->entry = entry;
  86         clip_vcc->xoff = 0; /* @@@ may overrun buffer by one packet */
  87         clip_vcc->next = entry->vccs;
  88         entry->vccs = clip_vcc;
  89         entry->neigh->used = jiffies;
  90 }
  91
  92
  93 static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
  94 {
  95         struct atmarp_entry *entry = clip_vcc->entry;
  96         struct clip_vcc **walk;
  97
  98         if (!entry) {
  99                 printk(KERN_CRIT "!clip_vcc->entry (clip_vcc %p)\n",clip_vcc);
 100                 return;
 101         }
 102         spin_lock_bh(&entry->neigh->dev->xmit_lock);    /* block clip_start_xmit() */
 103         entry->neigh->used = jiffies;
 104         for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
 105                 if (*walk == clip_vcc) {
 106                         int error;
 107
 108                         *walk = clip_vcc->next; /* atomic */
 109                         clip_vcc->entry = NULL;
 110                         if (clip_vcc->xoff)
 111                                 netif_wake_queue(entry->neigh->dev);
 112                         if (entry->vccs)
 113                                 goto out;
 114                         entry->expires = jiffies-1;
 115                                 /* force resolution or expiration */
 116                         error = neigh_update(entry->neigh, NULL, NUD_NONE,
 117                                              NEIGH_UPDATE_F_ADMIN);
 118                         if (error)
 119                                 printk(KERN_CRIT "unlink_clip_vcc: "
 120                                     "neigh_update failed with %d\n",error);
 121                         goto out;
 122                 }
 123         printk(KERN_CRIT "ATMARP: unlink_clip_vcc failed (entry %p, vcc "
 124           "0x%p)\n",entry,clip_vcc);
 125 out:
 126         spin_unlock_bh(&entry->neigh->dev->xmit_lock);
 127 }
 128
 129 /* The neighbour entry n->lock is held. */
 130 static int neigh_check_cb(struct neighbour *n)
 131 {
 132         struct atmarp_entry *entry = NEIGH2ENTRY(n);
 133         struct clip_vcc *cv;
 134
 135         for (cv = entry->vccs; cv; cv = cv->next) {
 136                 unsigned long exp = cv->last_use + cv->idle_timeout;
 137
 138                 if (cv->idle_timeout && time_after(jiffies, exp)) {
 139                         DPRINTK("releasing vcc %p->%p of entry %p\n",
 140                                 cv, cv->vcc, entry);
 141                         vcc_release_async(cv->vcc, -ETIMEDOUT);
 142                 }
 143         }
 144
 145         if (entry->vccs || time_before(jiffies, entry->expires))
 146                 return 0;
 147
 148         if (atomic_read(&n->refcnt) > 1) {
 149                 struct sk_buff *skb;
 150
 151                 DPRINTK("destruction postponed with ref %d\n",
 152                         atomic_read(&n->refcnt));
 153
 154                 while ((skb = skb_dequeue(&n->arp_queue)) != NULL)
 155                         dev_kfree_skb(skb);
 156
 157                 return 0;
 158         }
 159
 160         DPRINTK("expired neigh %p\n",n);
 161         return 1;
 162 }
 163
 164 static void idle_timer_check(unsigned long dummy)
 165 {
 166         write_lock(&clip_tbl.lock);
 167         __neigh_for_each_release(&clip_tbl, neigh_check_cb);
 168         mod_timer(&idle_timer, jiffies+CLIP_CHECK_INTERVAL*HZ);
 169         write_unlock(&clip_tbl.lock);
 170 }
 171
 172 static int clip_arp_rcv(struct sk_buff *skb)
 173 {
 174         struct atm_vcc *vcc;
 175
 176         DPRINTK("clip_arp_rcv\n");
 177         vcc = ATM_SKB(skb)->vcc;
 178         if (!vcc || !atm_charge(vcc,skb->truesize)) {
 179                 dev_kfree_skb_any(skb);
 180                 return 0;
 181         }
 182         DPRINTK("pushing to %p\n",vcc);
 183         DPRINTK("using %p\n",CLIP_VCC(vcc)->old_push);
 184         CLIP_VCC(vcc)->old_push(vcc,skb);
 185         return 0;
 186 }
 187
 188 static const unsigned char llc_oui[] = {
 189         0xaa,   /* DSAP: non-ISO */
 190         0xaa,   /* SSAP: non-ISO */
 191         0x03,   /* Ctrl: Unnumbered Information Command PDU */
 192         0x00,   /* OUI: EtherType */
 193         0x00,
 194         0x00 };
 195
 196 static void clip_push(struct atm_vcc *vcc,struct sk_buff *skb)
 197 {
 198         struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
 199
 200         DPRINTK("clip push\n");
 201         if (!skb) {
 202                 DPRINTK("removing VCC %p\n",clip_vcc);
 203                 if (clip_vcc->entry) unlink_clip_vcc(clip_vcc);
 204                 clip_vcc->old_push(vcc,NULL); /* pass on the bad news */
 205                 kfree(clip_vcc);
 206                 return;
 207         }
 208         atm_return(vcc,skb->truesize);
 209         skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
 210                 /* clip_vcc->entry == NULL if we don't have an IP address yet */
 211         if (!skb->dev) {
 212                 dev_kfree_skb_any(skb);
 213                 return;
 214         }
 215         ATM_SKB(skb)->vcc = vcc;
 216         skb->mac.raw = skb->data;
 217         if (!clip_vcc->encap || skb->len < RFC1483LLC_LEN || memcmp(skb->data,
 218             llc_oui,sizeof(llc_oui))) skb->protocol = htons(ETH_P_IP);
 219         else {
 220                 skb->protocol = ((u16 *) skb->data)[3];
 221                 skb_pull(skb,RFC1483LLC_LEN);
 222                 if (skb->protocol == htons(ETH_P_ARP)) {
 223                         PRIV(skb->dev)->stats.rx_packets++;
 224                         PRIV(skb->dev)->stats.rx_bytes += skb->len;
 225                         clip_arp_rcv(skb);
 226                         return;
 227                 }
 228         }
 229         clip_vcc->last_use = jiffies;
 230         PRIV(skb->dev)->stats.rx_packets++;
 231         PRIV(skb->dev)->stats.rx_bytes += skb->len;
 232         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
 233         netif_rx(skb);
 234 }
 235
 236
 237 /*
 238  * Note: these spinlocks _must_not_ block on non-SMP. The only goal is that
 239  * clip_pop is atomic with respect to the critical section in clip_start_xmit.
 240  */
 241
 242
 243 static void clip_pop(struct atm_vcc *vcc,struct sk_buff *skb)
 244 {
 245         struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
 246         struct net_device *dev = skb->dev;
 247         int old;
 248         unsigned long flags;
 249
 250         DPRINTK("clip_pop(vcc %p)\n",vcc);
 251         clip_vcc->old_pop(vcc,skb);
 252         /* skb->dev == NULL in outbound ARP packets */
 253         if (!dev) return;
 254         spin_lock_irqsave(&PRIV(dev)->xoff_lock,flags);
 255         if (atm_may_send(vcc,0)) {
 256                 old = xchg(&clip_vcc->xoff,0);
 257                 if (old) netif_wake_queue(dev);
 258         }
 259         spin_unlock_irqrestore(&PRIV(dev)->xoff_lock,flags);
 260 }
 261
 262
 263 static void clip_neigh_destroy(struct neighbour *neigh)
 264 {
 265         DPRINTK("clip_neigh_destroy (neigh %p)\n",neigh);
 266         if (NEIGH2ENTRY(neigh)->vccs)
 267                 printk(KERN_CRIT "clip_neigh_destroy: vccs != NULL !!!\n");
 268         NEIGH2ENTRY(neigh)->vccs = (void *) 0xdeadbeef;
 269 }
 270
 271
 272 static void clip_neigh_solicit(struct neighbour *neigh,struct sk_buff *skb)
 273 {
 274         DPRINTK("clip_neigh_solicit (neigh %p, skb %p)\n",neigh,skb);
 275         to_atmarpd(act_need,PRIV(neigh->dev)->number,NEIGH2ENTRY(neigh)->ip);
 276 }
 277
 278
 279 static void clip_neigh_error(struct neighbour *neigh,struct sk_buff *skb)
 280 {
 281 #ifndef CONFIG_ATM_CLIP_NO_ICMP
 282         icmp_send(skb,ICMP_DEST_UNREACH,ICMP_HOST_UNREACH,0);
 283 #endif
 284         kfree_skb(skb);
 285 }
 286
 287
 288 static struct neigh_ops clip_neigh_ops = {
 289         .family =               AF_INET,
 290         .solicit =              clip_neigh_solicit,
 291         .error_report =         clip_neigh_error,
 292         .output =               dev_queue_xmit,
 293         .connected_output =     dev_queue_xmit,
 294         .hh_output =            dev_queue_xmit,
 295         .queue_xmit =           dev_queue_xmit,
 296 };
 297
 298
 299 static int clip_constructor(struct neighbour *neigh)
 300 {
 301         struct atmarp_entry *entry = NEIGH2ENTRY(neigh);
 302         struct net_device *dev = neigh->dev;
 303         struct in_device *in_dev;
 304         struct neigh_parms *parms;
 305
 306         DPRINTK("clip_constructor (neigh %p, entry %p)\n",neigh,entry);
 307         neigh->type = inet_addr_type(entry->ip);
 308         if (neigh->type != RTN_UNICAST) return -EINVAL;
 309
 310         rcu_read_lock();
 311         in_dev = __in_dev_get_rcu(dev);
 312         if (!in_dev) {
 313                 rcu_read_unlock();
 314                 return -EINVAL;
 315         }
 316
 317         parms = in_dev->arp_parms;
 318         __neigh_parms_put(neigh->parms);
 319         neigh->parms = neigh_parms_clone(parms);
 320         rcu_read_unlock();
 321
 322         neigh->ops = &clip_neigh_ops;
 323         neigh->output = neigh->nud_state & NUD_VALID ?
 324             neigh->ops->connected_output : neigh->ops->output;
 325         entry->neigh = neigh;
 326         entry->vccs = NULL;
 327         entry->expires = jiffies-1;
 328         return 0;
 329 }
 330
 331 static u32 clip_hash(const void *pkey, const struct net_device *dev)
 332 {
 333         return jhash_2words(*(u32 *)pkey, dev->ifindex, clip_tbl.hash_rnd);
 334 }
 335
 336 static struct neigh_table clip_tbl = {
 337         .family         = AF_INET,
 338         .entry_size     = sizeof(struct neighbour)+sizeof(struct atmarp_entry),
 339         .key_len        = 4,
 340         .hash           = clip_hash,
 341         .constructor    = clip_constructor,
 342         .id             = "clip_arp_cache",
 343
 344         /* parameters are copied from ARP ... */
 345         .parms = {
 346                 .tbl                    = &clip_tbl,
 347                 .neigh_destructor       = clip_neigh_destroy,
 348                 .base_reachable_time    = 30 * HZ,
 349                 .retrans_time           = 1 * HZ,
 350                 .gc_staletime           = 60 * HZ,
 351                 .reachable_time         = 30 * HZ,
 352                 .delay_probe_time       = 5 * HZ,
 353                 .queue_len              = 3,
 354                 .ucast_probes           = 3,
 355                 .mcast_probes           = 3,
 356                 .anycast_delay          = 1 * HZ,
 357                 .proxy_delay            = (8 * HZ) / 10,
 358                 .proxy_qlen             = 64,
 359                 .locktime               = 1 * HZ,
 360         },
 361         .gc_interval    = 30 * HZ,
 362         .gc_thresh1     = 128,
 363         .gc_thresh2     = 512,
 364         .gc_thresh3     = 1024,
 365 };
 366
 367
 368 /* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
 369
 370 /*
 371  * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
 372  * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
 373  * don't increment the usage count. This is used to create entries in
 374  * clip_setentry.
 375  */
 376
 377
 378 static int clip_encap(struct atm_vcc *vcc,int mode)
 379 {
 380         CLIP_VCC(vcc)->encap = mode;
 381         return 0;
 382 }
 383
 384
 385 static int clip_start_xmit(struct sk_buff *skb,struct net_device *dev)
 386 {
 387         struct clip_priv *clip_priv = PRIV(dev);
 388         struct atmarp_entry *entry;
 389         struct atm_vcc *vcc;
 390         int old;
 391         unsigned long flags;
 392
 393         DPRINTK("clip_start_xmit (skb %p)\n",skb);
 394         if (!skb->dst) {
 395                 printk(KERN_ERR "clip_start_xmit: skb->dst == NULL\n");
 396                 dev_kfree_skb(skb);
 397                 clip_priv->stats.tx_dropped++;
 398                 return 0;
 399         }
 400         if (!skb->dst->neighbour) {
 401 #if 0
 402                 skb->dst->neighbour = clip_find_neighbour(skb->dst,1);
 403                 if (!skb->dst->neighbour) {
 404                         dev_kfree_skb(skb); /* lost that one */
 405                         clip_priv->stats.tx_dropped++;
 406                         return 0;
 407                 }
 408 #endif
 409                 printk(KERN_ERR "clip_start_xmit: NO NEIGHBOUR !\n");
 410                 dev_kfree_skb(skb);
 411                 clip_priv->stats.tx_dropped++;
 412                 return 0;
 413         }
 414         entry = NEIGH2ENTRY(skb->dst->neighbour);
 415         if (!entry->vccs) {
 416                 if (time_after(jiffies, entry->expires)) {
 417                         /* should be resolved */
 418                         entry->expires = jiffies+ATMARP_RETRY_DELAY*HZ;
 419                         to_atmarpd(act_need,PRIV(dev)->number,entry->ip);
 420                 }
 421                 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
 422                         skb_queue_tail(&entry->neigh->arp_queue,skb);
 423                 else {
 424                         dev_kfree_skb(skb);
 425                         clip_priv->stats.tx_dropped++;
 426                 }
 427                 return 0;
 428         }
 429         DPRINTK("neigh %p, vccs %p\n",entry,entry->vccs);
 430         ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
 431         DPRINTK("using neighbour %p, vcc %p\n",skb->dst->neighbour,vcc);
 432         if (entry->vccs->encap) {
 433                 void *here;
 434
 435                 here = skb_push(skb,RFC1483LLC_LEN);
 436                 memcpy(here,llc_oui,sizeof(llc_oui));
 437                 ((u16 *) here)[3] = skb->protocol;
 438         }
 439         atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
 440         ATM_SKB(skb)->atm_options = vcc->atm_options;
 441         entry->vccs->last_use = jiffies;
 442         DPRINTK("atm_skb(%p)->vcc(%p)->dev(%p)\n",skb,vcc,vcc->dev);
 443         old = xchg(&entry->vccs->xoff,1); /* assume XOFF ... */
 444         if (old) {
 445                 printk(KERN_WARNING "clip_start_xmit: XOFF->XOFF transition\n");
 446                 return 0;
 447         }
 448         clip_priv->stats.tx_packets++;
 449         clip_priv->stats.tx_bytes += skb->len;
 450         (void) vcc->send(vcc,skb);
 451         if (atm_may_send(vcc,0)) {
 452                 entry->vccs->xoff = 0;
 453                 return 0;
 454         }
 455         spin_lock_irqsave(&clip_priv->xoff_lock,flags);
 456         netif_stop_queue(dev); /* XOFF -> throttle immediately */
 457         barrier();
 458         if (!entry->vccs->xoff)
 459                 netif_start_queue(dev);
 460                 /* Oh, we just raced with clip_pop. netif_start_queue should be
 461                    good enough, because nothing should really be asleep because
 462                    of the brief netif_stop_queue. If this isn't true or if it
 463                    changes, use netif_wake_queue instead. */
 464         spin_unlock_irqrestore(&clip_priv->xoff_lock,flags);
 465         return 0;
 466 }
 467
 468
 469 static struct net_device_stats *clip_get_stats(struct net_device *dev)
 470 {
 471         return &PRIV(dev)->stats;
 472 }
 473
 474
 475 static int clip_mkip(struct atm_vcc *vcc,int timeout)
 476 {
 477         struct clip_vcc *clip_vcc;
 478         struct sk_buff_head copy;
 479         struct sk_buff *skb;
 480
 481         if (!vcc->push) return -EBADFD;
 482         clip_vcc = kmalloc(sizeof(struct clip_vcc),GFP_KERNEL);
 483         if (!clip_vcc) return -ENOMEM;
 484         DPRINTK("mkip clip_vcc %p vcc %p\n",clip_vcc,vcc);
 485         clip_vcc->vcc = vcc;
 486         vcc->user_back = clip_vcc;
 487         set_bit(ATM_VF_IS_CLIP, &vcc->flags);
 488         clip_vcc->entry = NULL;
 489         clip_vcc->xoff = 0;
 490         clip_vcc->encap = 1;
 491         clip_vcc->last_use = jiffies;
 492         clip_vcc->idle_timeout = timeout*HZ;
 493         clip_vcc->old_push = vcc->push;
 494         clip_vcc->old_pop = vcc->pop;
 495         vcc->push = clip_push;
 496         vcc->pop = clip_pop;
 497         skb_queue_head_init(&copy);
 498         skb_migrate(&sk_atm(vcc)->sk_receive_queue, &copy);
 499         /* re-process everything received between connection setup and MKIP */
 500         while ((skb = skb_dequeue(&copy)) != NULL)
 501                 if (!clip_devs) {
 502                         atm_return(vcc,skb->truesize);
 503                         kfree_skb(skb);
 504                 }
 505                 else {
 506                         unsigned int len = skb->len;
 507
 508                         clip_push(vcc,skb);
 509                         PRIV(skb->dev)->stats.rx_packets--;
 510                         PRIV(skb->dev)->stats.rx_bytes -= len;
 511                 }
 512         return 0;
 513 }
 514
 515
 516 static int clip_setentry(struct atm_vcc *vcc,u32 ip)
 517 {
 518         struct neighbour *neigh;
 519         struct atmarp_entry *entry;
 520         int error;
 521         struct clip_vcc *clip_vcc;
 522         struct flowi fl = { .nl_u = { .ip4_u = { .daddr = ip, .tos = 1 } } };
 523         struct rtable *rt;
 524
 525         if (vcc->push != clip_push) {
 526                 printk(KERN_WARNING "clip_setentry: non-CLIP VCC\n");
 527                 return -EBADF;
 528         }
 529         clip_vcc = CLIP_VCC(vcc);
 530         if (!ip) {
 531                 if (!clip_vcc->entry) {
 532                         printk(KERN_ERR "hiding hidden ATMARP entry\n");
 533                         return 0;
 534                 }
 535                 DPRINTK("setentry: remove\n");
 536                 unlink_clip_vcc(clip_vcc);
 537                 return 0;
 538         }
 539         error = ip_route_output_key(&rt,&fl);
 540         if (error) return error;
 541         neigh = __neigh_lookup(&clip_tbl,&ip,rt->u.dst.dev,1);
 542         ip_rt_put(rt);
 543         if (!neigh)
 544                 return -ENOMEM;
 545         entry = NEIGH2ENTRY(neigh);
 546         if (entry != clip_vcc->entry) {
 547                 if (!clip_vcc->entry) DPRINTK("setentry: add\n");
 548                 else {
 549                         DPRINTK("setentry: update\n");
 550                         unlink_clip_vcc(clip_vcc);
 551                 }
 552                 link_vcc(clip_vcc,entry);
 553         }
 554         error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
 555                              NEIGH_UPDATE_F_OVERRIDE|NEIGH_UPDATE_F_ADMIN);
 556         neigh_release(neigh);
 557         return error;
 558 }
 559
 560
 561 static void clip_setup(struct net_device *dev)
 562 {
 563         dev->hard_start_xmit = clip_start_xmit;
 564         /* sg_xmit ... */
 565         dev->get_stats = clip_get_stats;
 566         dev->type = ARPHRD_ATM;
 567         dev->hard_header_len = RFC1483LLC_LEN;
 568         dev->mtu = RFC1626_MTU;
 569         dev->tx_queue_len = 100; /* "normal" queue (packets) */
 570             /* When using a "real" qdisc, the qdisc determines the queue */
 571             /* length. tx_queue_len is only used for the default case, */
 572             /* without any more elaborate queuing. 100 is a reasonable */
 573             /* compromise between decent burst-tolerance and protection */
 574             /* against memory hogs. */
 575 }
 576
 577
 578 static int clip_create(int number)
 579 {
 580         struct net_device *dev;
 581         struct clip_priv *clip_priv;
 582         int error;
 583
 584         if (number != -1) {
 585                 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
 586                         if (PRIV(dev)->number == number) return -EEXIST;
 587         }
 588         else {
 589                 number = 0;
 590                 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
 591                         if (PRIV(dev)->number >= number)
 592                                 number = PRIV(dev)->number+1;
 593         }
 594         dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
 595         if (!dev)
 596                 return -ENOMEM;
 597         clip_priv = PRIV(dev);
 598         sprintf(dev->name,"atm%d",number);
 599         spin_lock_init(&clip_priv->xoff_lock);
 600         clip_priv->number = number;
 601         error = register_netdev(dev);
 602         if (error) {
 603                 free_netdev(dev);
 604                 return error;
 605         }
 606         clip_priv->next = clip_devs;
 607         clip_devs = dev;
 608         DPRINTK("registered (net:%s)\n",dev->name);
 609         return number;
 610 }
 611
 612
 613 static int clip_device_event(struct notifier_block *this,unsigned long event,
 614                              void *arg)
 615 {
 616         struct net_device *dev = arg;
 617
 618         if (event == NETDEV_UNREGISTER) {
 619                 neigh_ifdown(&clip_tbl, dev);
 620                 return NOTIFY_DONE;
 621         }
 622
 623         /* ignore non-CLIP devices */
 624         if (dev->type != ARPHRD_ATM || dev->hard_start_xmit != clip_start_xmit)
 625                 return NOTIFY_DONE;
 626
 627         switch (event) {
 628                 case NETDEV_UP:
 629                         DPRINTK("clip_device_event NETDEV_UP\n");
 630                         (void) to_atmarpd(act_up,PRIV(dev)->number,0);
 631                         break;
 632                 case NETDEV_GOING_DOWN:
 633                         DPRINTK("clip_device_event NETDEV_DOWN\n");
 634                         (void) to_atmarpd(act_down,PRIV(dev)->number,0);
 635                         break;
 636                 case NETDEV_CHANGE:
 637                 case NETDEV_CHANGEMTU:
 638                         DPRINTK("clip_device_event NETDEV_CHANGE*\n");
 639                         (void) to_atmarpd(act_change,PRIV(dev)->number,0);
 640                         break;
 641                 case NETDEV_REBOOT:
 642                 case NETDEV_REGISTER:
 643                 case NETDEV_DOWN:
 644                         DPRINTK("clip_device_event %ld\n",event);
 645                         /* ignore */
 646                         break;
 647                 default:
 648                         printk(KERN_WARNING "clip_device_event: unknown event "
 649                             "%ld\n",event);
 650                         break;
 651         }
 652         return NOTIFY_DONE;
 653 }
 654
 655
 656 static int clip_inet_event(struct notifier_block *this,unsigned long event,
 657     void *ifa)
 658 {
 659         struct in_device *in_dev;
 660
 661         in_dev = ((struct in_ifaddr *) ifa)->ifa_dev;
 662         if (!in_dev || !in_dev->dev) {
 663                 printk(KERN_WARNING "clip_inet_event: no device\n");
 664                 return NOTIFY_DONE;
 665         }
 666         /*
 667          * Transitions are of the down-change-up type, so it's sufficient to
 668          * handle the change on up.
 669          */
 670         if (event != NETDEV_UP) return NOTIFY_DONE;
 671         return clip_device_event(this,NETDEV_CHANGE,in_dev->dev);
 672 }
 673
 674
 675 static struct notifier_block clip_dev_notifier = {
 676         clip_device_event,
 677         NULL,
 678         0
 679 };
 680
 681
 682
 683 static struct notifier_block clip_inet_notifier = {
 684         clip_inet_event,
 685         NULL,
 686         0
 687 };
 688
 689
 690
 691 static void atmarpd_close(struct atm_vcc *vcc)
 692 {
 693         DPRINTK("atmarpd_close\n");
 694
 695         rtnl_lock();
 696         atmarpd = NULL;
 697         skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
 698         rtnl_unlock();
 699
 700         DPRINTK("(done)\n");
 701         module_put(THIS_MODULE);
 702 }
 703
 704
 705 static struct atmdev_ops atmarpd_dev_ops = {
 706         .close = atmarpd_close
 707 };
 708
 709
 710 static struct atm_dev atmarpd_dev = {
 711         .ops =                  &atmarpd_dev_ops,
 712         .type =                 "arpd",
 713         .number =               999,
 714         .lock =                 SPIN_LOCK_UNLOCKED
 715 };
 716
 717
 718 static int atm_init_atmarp(struct atm_vcc *vcc)
 719 {
 720         rtnl_lock();
 721         if (atmarpd) {
 722                 rtnl_unlock();
 723                 return -EADDRINUSE;
 724         }
 725
 726         mod_timer(&idle_timer, jiffies+CLIP_CHECK_INTERVAL*HZ);
 727
 728         atmarpd = vcc;
 729         set_bit(ATM_VF_META,&vcc->flags);
 730         set_bit(ATM_VF_READY,&vcc->flags);
 731             /* allow replies and avoid getting closed if signaling dies */
 732         vcc->dev = &atmarpd_dev;
 733         vcc_insert_socket(sk_atm(vcc));
 734         vcc->push = NULL;
 735         vcc->pop = NULL; /* crash */
 736         vcc->push_oam = NULL; /* crash */
 737         rtnl_unlock();
 738         return 0;
 739 }
 740
 741 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 742 {
 743         struct atm_vcc *vcc = ATM_SD(sock);
 744         int err = 0;
 745
 746         switch (cmd) {
 747                 case SIOCMKCLIP:
 748                 case ATMARPD_CTRL:
 749                 case ATMARP_MKIP:
 750                 case ATMARP_SETENTRY:
 751                 case ATMARP_ENCAP:
 752                         if (!capable(CAP_NET_ADMIN))
 753                                 return -EPERM;
 754                         break;
 755                 default:
 756                         return -ENOIOCTLCMD;
 757         }
 758
 759         switch (cmd) {
 760                 case SIOCMKCLIP:
 761                         err = clip_create(arg);
 762                         break;
 763                 case ATMARPD_CTRL:
 764                         err = atm_init_atmarp(vcc);
 765                         if (!err) {
 766                                 sock->state = SS_CONNECTED;
 767                                 __module_get(THIS_MODULE);
 768                         }
 769                         break;
 770                 case ATMARP_MKIP:
 771                         err = clip_mkip(vcc ,arg);
 772                         break;
 773                 case ATMARP_SETENTRY:
 774                         err = clip_setentry(vcc, arg);
 775                         break;
 776                 case ATMARP_ENCAP:
 777                         err = clip_encap(vcc, arg);
 778                         break;
 779         }
 780         return err;
 781 }
 782
 783 static struct atm_ioctl clip_ioctl_ops = {
 784         .owner  = THIS_MODULE,
 785         .ioctl  = clip_ioctl,
 786 };
 787
 788 #ifdef CONFIG_PROC_FS
 789
 790 static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
 791 {
 792         static int code[] = { 1,2,10,6,1,0 };
 793         static int e164[] = { 1,8,4,6,1,0 };
 794
 795         if (*addr->sas_addr.pub) {
 796                 seq_printf(seq, "%s", addr->sas_addr.pub);
 797                 if (*addr->sas_addr.prv)
 798                         seq_putc(seq, '+');
 799         } else if (!*addr->sas_addr.prv) {
 800                 seq_printf(seq, "%s", "(none)");
 801                 return;
 802         }
 803         if (*addr->sas_addr.prv) {
 804                 unsigned char *prv = addr->sas_addr.prv;
 805                 int *fields;
 806                 int i, j;
 807
 808                 fields = *prv == ATM_AFI_E164 ? e164 : code;
 809                 for (i = 0; fields[i]; i++) {
 810                         for (j = fields[i]; j; j--)
 811                                 seq_printf(seq, "%02X", *prv++);
 812                         if (fields[i+1])
 813                                 seq_putc(seq, '.');
 814                 }
 815         }
 816 }
 817
 818 /* This means the neighbour entry has no attached VCC objects. */
 819 #define SEQ_NO_VCC_TOKEN        ((void *) 2)
 820
 821 static void atmarp_info(struct seq_file *seq, struct net_device *dev,
 822                         struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
 823 {
 824         unsigned long exp;
 825         char buf[17];
 826         int svc, llc, off;
 827
 828         svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
 829                (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
 830
 831         llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
 832                clip_vcc->encap);
 833
 834         if (clip_vcc == SEQ_NO_VCC_TOKEN)
 835                 exp = entry->neigh->used;
 836         else
 837                 exp = clip_vcc->last_use;
 838
 839         exp = (jiffies - exp) / HZ;
 840
 841         seq_printf(seq, "%-6s%-4s%-4s%5ld ",
 842                    dev->name,
 843                    svc ? "SVC" : "PVC",
 844                    llc ? "LLC" : "NULL",
 845                    exp);
 846
 847         off = scnprintf(buf, sizeof(buf) - 1, "%d.%d.%d.%d",
 848                         NIPQUAD(entry->ip));
 849         while (off < 16)
 850                 buf[off++] = ' ';
 851         buf[off] = '\0';
 852         seq_printf(seq, "%s", buf);
 853
 854         if (clip_vcc == SEQ_NO_VCC_TOKEN) {
 855                 if (time_before(jiffies, entry->expires))
 856                         seq_printf(seq, "(resolving)\n");
 857                 else
 858                         seq_printf(seq, "(expired, ref %d)\n",
 859                                    atomic_read(&entry->neigh->refcnt));
 860         } else if (!svc) {
 861                 seq_printf(seq, "%d.%d.%d\n",
 862                            clip_vcc->vcc->dev->number,
 863                            clip_vcc->vcc->vpi,
 864                            clip_vcc->vcc->vci);
 865         } else {
 866                 svc_addr(seq, &clip_vcc->vcc->remote);
 867                 seq_putc(seq, '\n');
 868         }
 869 }
 870
 871 struct clip_seq_state {
 872         /* This member must be first. */
 873         struct neigh_seq_state ns;
 874
 875         /* Local to clip specific iteration. */
 876         struct clip_vcc *vcc;
 877 };
 878
 879 static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
 880                                           struct clip_vcc *curr)
 881 {
 882         if (!curr) {
 883                 curr = e->vccs;
 884                 if (!curr)
 885                         return SEQ_NO_VCC_TOKEN;
 886                 return curr;
 887         }
 888         if (curr == SEQ_NO_VCC_TOKEN)
 889                 return NULL;
 890
 891         curr = curr->next;
 892
 893         return curr;
 894 }
 895
 896 static void *clip_seq_vcc_walk(struct clip_seq_state *state,
 897                                struct atmarp_entry *e, loff_t *pos)
 898 {
 899         struct clip_vcc *vcc = state->vcc;
 900
 901         vcc = clip_seq_next_vcc(e, vcc);
 902         if (vcc && pos != NULL) {
 903                 while (*pos) {
 904                         vcc = clip_seq_next_vcc(e, vcc);
 905                         if (!vcc)
 906                                 break;
 907                         --(*pos);
 908                 }
 909         }
 910         state->vcc = vcc;
 911
 912         return vcc;
 913 }
 914
 915 static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
 916                                struct neighbour *n, loff_t *pos)
 917 {
 918         struct clip_seq_state *state = (struct clip_seq_state *) _state;
 919
 920         return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos);
 921 }
 922
 923 static void *clip_seq_start(struct seq_file *seq, loff_t *pos)
 924 {
 925         return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY);
 926 }
 927
 928 static int clip_seq_show(struct seq_file *seq, void *v)
 929 {
 930         static char atm_arp_banner[] =
 931                 "IPitf TypeEncp Idle IP address      ATM address\n";
 932
 933         if (v == SEQ_START_TOKEN) {
 934                 seq_puts(seq, atm_arp_banner);
 935         } else {
 936                 struct clip_seq_state *state = seq->private;
 937                 struct neighbour *n = v;
 938                 struct clip_vcc *vcc = state->vcc;
 939
 940                 atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
 941         }
 942         return 0;
 943 }
 944
 945 static struct seq_operations arp_seq_ops = {
 946         .start  = clip_seq_start,
 947         .next   = neigh_seq_next,
 948         .stop   = neigh_seq_stop,
 949         .show   = clip_seq_show,
 950 };
 951
 952 static int arp_seq_open(struct inode *inode, struct file *file)
 953 {
 954         struct clip_seq_state *state;
 955         struct seq_file *seq;
 956         int rc = -EAGAIN;
 957
 958         state = kmalloc(sizeof(*state), GFP_KERNEL);
 959         if (!state) {
 960                 rc = -ENOMEM;
 961                 goto out_kfree;
 962         }
 963         memset(state, 0, sizeof(*state));
 964         state->ns.neigh_sub_iter = clip_seq_sub_iter;
 965
 966         rc = seq_open(file, &arp_seq_ops);
 967         if (rc)
 968                 goto out_kfree;
 969
 970         seq = file->private_data;
 971         seq->private = state;
 972 out:
 973         return rc;
 974
 975 out_kfree:
 976         kfree(state);
 977         goto out;
 978 }
 979
 980 static struct file_operations arp_seq_fops = {
 981         .open           = arp_seq_open,
 982         .read           = seq_read,
 983         .llseek         = seq_lseek,
 984         .release        = seq_release_private,
 985         .owner          = THIS_MODULE
 986 };
 987 #endif
 988
 989 static int __init atm_clip_init(void)
 990 {
 991         neigh_table_init(&clip_tbl);
 992
 993         clip_tbl_hook = &clip_tbl;
 994         register_atm_ioctl(&clip_ioctl_ops);
 995         register_netdevice_notifier(&clip_dev_notifier);
 996         register_inetaddr_notifier(&clip_inet_notifier);
 997
 998         setup_timer(&idle_timer, idle_timer_check, 0);
 999
1000 #ifdef CONFIG_PROC_FS
1001 {
1002         struct proc_dir_entry *p;
1003
1004         p = create_proc_entry("arp", S_IRUGO, atm_proc_root);
1005         if (p)
1006                 p->proc_fops = &arp_seq_fops;
1007 }
1008 #endif
1009
1010         return 0;
1011 }
1012
1013 static void __exit atm_clip_exit(void)
1014 {
1015         struct net_device *dev, *next;
1016
1017         remove_proc_entry("arp", atm_proc_root);
1018
1019         unregister_inetaddr_notifier(&clip_inet_notifier);
1020         unregister_netdevice_notifier(&clip_dev_notifier);
1021
1022         deregister_atm_ioctl(&clip_ioctl_ops);
1023
1024         /* First, stop the idle timer, so it stops banging
1025          * on the table.
1026          */
1027         del_timer_sync(&idle_timer);
1028
1029         /* Next, purge the table, so that the device
1030          * unregister loop below does not hang due to
1031          * device references remaining in the table.
1032          */
1033         neigh_ifdown(&clip_tbl, NULL);
1034
1035         dev = clip_devs;
1036         while (dev) {
1037                 next = PRIV(dev)->next;
1038                 unregister_netdev(dev);
1039                 free_netdev(dev);
1040                 dev = next;
1041         }
1042
1043         /* Now it is safe to fully shutdown whole table. */
1044         neigh_table_clear(&clip_tbl);
1045
1046         clip_tbl_hook = NULL;
1047 }
1048
1049 module_init(atm_clip_init);
1050 module_exit(atm_clip_exit);
1051
1052 MODULE_LICENSE("GPL");