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 .hh_output = dev_queue_xmit, 277 .queue_xmit = dev_queue_xmit, 278 }; 279 280 static int clip_constructor(struct neighbour *neigh) 281 { 282 struct atmarp_entry *entry = NEIGH2ENTRY(neigh); 283 struct net_device *dev = neigh->dev; 284 struct in_device *in_dev; 285 struct neigh_parms *parms; 286 287 pr_debug("(neigh %p, entry %p)\n", neigh, entry); 288 neigh->type = inet_addr_type(&init_net, entry->ip); 289 if (neigh->type != RTN_UNICAST) 290 return -EINVAL; 291 292 rcu_read_lock(); 293 in_dev = __in_dev_get_rcu(dev); 294 if (!in_dev) { 295 rcu_read_unlock(); 296 return -EINVAL; 297 } 298 299 parms = in_dev->arp_parms; 300 __neigh_parms_put(neigh->parms); 301 neigh->parms = neigh_parms_clone(parms); 302 rcu_read_unlock(); 303 304 neigh->ops = &clip_neigh_ops; 305 neigh->output = neigh->nud_state & NUD_VALID ? 306 neigh->ops->connected_output : neigh->ops->output; 307 entry->neigh = neigh; 308 entry->vccs = NULL; 309 entry->expires = jiffies - 1; 310 return 0; 311 } 312 313 static u32 clip_hash(const void *pkey, const struct net_device *dev, __u32 rnd) 314 { 315 return jhash_2words(*(u32 *) pkey, dev->ifindex, rnd); 316 } 317 318 static struct neigh_table clip_tbl = { 319 .family = AF_INET, 320 .entry_size = sizeof(struct neighbour)+sizeof(struct atmarp_entry), 321 .key_len = 4, 322 .hash = clip_hash, 323 .constructor = clip_constructor, 324 .id = "clip_arp_cache", 325 326 /* parameters are copied from ARP ... */ 327 .parms = { 328 .tbl = &clip_tbl, 329 .base_reachable_time = 30 * HZ, 330 .retrans_time = 1 * HZ, 331 .gc_staletime = 60 * HZ, 332 .reachable_time = 30 * HZ, 333 .delay_probe_time = 5 * HZ, 334 .queue_len = 3, 335 .ucast_probes = 3, 336 .mcast_probes = 3, 337 .anycast_delay = 1 * HZ, 338 .proxy_delay = (8 * HZ) / 10, 339 .proxy_qlen = 64, 340 .locktime = 1 * HZ, 341 }, 342 .gc_interval = 30 * HZ, 343 .gc_thresh1 = 128, 344 .gc_thresh2 = 512, 345 .gc_thresh3 = 1024, 346 }; 347 348 /* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */ 349 350 /* 351 * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means 352 * to allocate the neighbour entry but not to ask atmarpd for resolution. Also, 353 * don't increment the usage count. This is used to create entries in 354 * clip_setentry. 355 */ 356 357 static int clip_encap(struct atm_vcc *vcc, int mode) 358 { 359 CLIP_VCC(vcc)->encap = mode; 360 return 0; 361 } 362 363 static netdev_tx_t clip_start_xmit(struct sk_buff *skb, 364 struct net_device *dev) 365 { 366 struct clip_priv *clip_priv = PRIV(dev); 367 struct atmarp_entry *entry; 368 struct atm_vcc *vcc; 369 int old; 370 unsigned long flags; 371 372 pr_debug("(skb %p)\n", skb); 373 if (!skb_dst(skb)) { 374 pr_err("skb_dst(skb) == NULL\n"); 375 dev_kfree_skb(skb); 376 dev->stats.tx_dropped++; 377 return NETDEV_TX_OK; 378 } 379 if (!skb_dst(skb)->neighbour) { 380 #if 0 381 skb_dst(skb)->neighbour = clip_find_neighbour(skb_dst(skb), 1); 382 if (!skb_dst(skb)->neighbour) { 383 dev_kfree_skb(skb); /* lost that one */ 384 dev->stats.tx_dropped++; 385 return 0; 386 } 387 #endif 388 pr_err("NO NEIGHBOUR !\n"); 389 dev_kfree_skb(skb); 390 dev->stats.tx_dropped++; 391 return NETDEV_TX_OK; 392 } 393 entry = NEIGH2ENTRY(skb_dst(skb)->neighbour); 394 if (!entry->vccs) { 395 if (time_after(jiffies, entry->expires)) { 396 /* should be resolved */ 397 entry->expires = jiffies + ATMARP_RETRY_DELAY * HZ; 398 to_atmarpd(act_need, PRIV(dev)->number, entry->ip); 399 } 400 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS) 401 skb_queue_tail(&entry->neigh->arp_queue, skb); 402 else { 403 dev_kfree_skb(skb); 404 dev->stats.tx_dropped++; 405 } 406 return NETDEV_TX_OK; 407 } 408 pr_debug("neigh %p, vccs %p\n", entry, entry->vccs); 409 ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc; 410 pr_debug("using neighbour %p, vcc %p\n", skb_dst(skb)->neighbour, vcc); 411 if (entry->vccs->encap) { 412 void *here; 413 414 here = skb_push(skb, RFC1483LLC_LEN); 415 memcpy(here, llc_oui, sizeof(llc_oui)); 416 ((__be16 *) here)[3] = skb->protocol; 417 } 418 atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc); 419 ATM_SKB(skb)->atm_options = vcc->atm_options; 420 entry->vccs->last_use = jiffies; 421 pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, vcc, vcc->dev); 422 old = xchg(&entry->vccs->xoff, 1); /* assume XOFF ... */ 423 if (old) { 424 pr_warning("XOFF->XOFF transition\n"); 425 return NETDEV_TX_OK; 426 } 427 dev->stats.tx_packets++; 428 dev->stats.tx_bytes += skb->len; 429 vcc->send(vcc, skb); 430 if (atm_may_send(vcc, 0)) { 431 entry->vccs->xoff = 0; 432 return NETDEV_TX_OK; 433 } 434 spin_lock_irqsave(&clip_priv->xoff_lock, flags); 435 netif_stop_queue(dev); /* XOFF -> throttle immediately */ 436 barrier(); 437 if (!entry->vccs->xoff) 438 netif_start_queue(dev); 439 /* Oh, we just raced with clip_pop. netif_start_queue should be 440 good enough, because nothing should really be asleep because 441 of the brief netif_stop_queue. If this isn't true or if it 442 changes, use netif_wake_queue instead. */ 443 spin_unlock_irqrestore(&clip_priv->xoff_lock, flags); 444 return NETDEV_TX_OK; 445 } 446 447 static int clip_mkip(struct atm_vcc *vcc, int timeout) 448 { 449 struct sk_buff_head *rq, queue; 450 struct clip_vcc *clip_vcc; 451 struct sk_buff *skb, *tmp; 452 unsigned long flags; 453 454 if (!vcc->push) 455 return -EBADFD; 456 clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL); 457 if (!clip_vcc) 458 return -ENOMEM; 459 pr_debug("%p vcc %p\n", clip_vcc, vcc); 460 clip_vcc->vcc = vcc; 461 vcc->user_back = clip_vcc; 462 set_bit(ATM_VF_IS_CLIP, &vcc->flags); 463 clip_vcc->entry = NULL; 464 clip_vcc->xoff = 0; 465 clip_vcc->encap = 1; 466 clip_vcc->last_use = jiffies; 467 clip_vcc->idle_timeout = timeout * HZ; 468 clip_vcc->old_push = vcc->push; 469 clip_vcc->old_pop = vcc->pop; 470 vcc->push = clip_push; 471 vcc->pop = clip_pop; 472 473 __skb_queue_head_init(&queue); 474 rq = &sk_atm(vcc)->sk_receive_queue; 475 476 spin_lock_irqsave(&rq->lock, flags); 477 skb_queue_splice_init(rq, &queue); 478 spin_unlock_irqrestore(&rq->lock, flags); 479 480 /* re-process everything received between connection setup and MKIP */ 481 skb_queue_walk_safe(&queue, skb, tmp) { 482 if (!clip_devs) { 483 atm_return(vcc, skb->truesize); 484 kfree_skb(skb); 485 } else { 486 struct net_device *dev = skb->dev; 487 unsigned int len = skb->len; 488 489 skb_get(skb); 490 clip_push(vcc, skb); 491 dev->stats.rx_packets--; 492 dev->stats.rx_bytes -= len; 493 kfree_skb(skb); 494 } 495 } 496 return 0; 497 } 498 499 static int clip_setentry(struct atm_vcc *vcc, __be32 ip) 500 { 501 struct neighbour *neigh; 502 struct atmarp_entry *entry; 503 int error; 504 struct clip_vcc *clip_vcc; 505 struct rtable *rt; 506 507 if (vcc->push != clip_push) { 508 pr_warning("non-CLIP VCC\n"); 509 return -EBADF; 510 } 511 clip_vcc = CLIP_VCC(vcc); 512 if (!ip) { 513 if (!clip_vcc->entry) { 514 pr_err("hiding hidden ATMARP entry\n"); 515 return 0; 516 } 517 pr_debug("remove\n"); 518 unlink_clip_vcc(clip_vcc); 519 return 0; 520 } 521 rt = ip_route_output(&init_net, ip, 0, 1, 0); 522 if (IS_ERR(rt)) 523 return PTR_ERR(rt); 524 neigh = __neigh_lookup(&clip_tbl, &ip, rt->dst.dev, 1); 525 ip_rt_put(rt); 526 if (!neigh) 527 return -ENOMEM; 528 entry = NEIGH2ENTRY(neigh); 529 if (entry != clip_vcc->entry) { 530 if (!clip_vcc->entry) 531 pr_debug("add\n"); 532 else { 533 pr_debug("update\n"); 534 unlink_clip_vcc(clip_vcc); 535 } 536 link_vcc(clip_vcc, entry); 537 } 538 error = neigh_update(neigh, llc_oui, NUD_PERMANENT, 539 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN); 540 neigh_release(neigh); 541 return error; 542 } 543 544 static const struct net_device_ops clip_netdev_ops = { 545 .ndo_start_xmit = clip_start_xmit, 546 }; 547 548 static void clip_setup(struct net_device *dev) 549 { 550 dev->netdev_ops = &clip_netdev_ops; 551 dev->type = ARPHRD_ATM; 552 dev->hard_header_len = RFC1483LLC_LEN; 553 dev->mtu = RFC1626_MTU; 554 dev->tx_queue_len = 100; /* "normal" queue (packets) */ 555 /* When using a "real" qdisc, the qdisc determines the queue */ 556 /* length. tx_queue_len is only used for the default case, */ 557 /* without any more elaborate queuing. 100 is a reasonable */ 558 /* compromise between decent burst-tolerance and protection */ 559 /* against memory hogs. */ 560 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 561 } 562 563 static int clip_create(int number) 564 { 565 struct net_device *dev; 566 struct clip_priv *clip_priv; 567 int error; 568 569 if (number != -1) { 570 for (dev = clip_devs; dev; dev = PRIV(dev)->next) 571 if (PRIV(dev)->number == number) 572 return -EEXIST; 573 } else { 574 number = 0; 575 for (dev = clip_devs; dev; dev = PRIV(dev)->next) 576 if (PRIV(dev)->number >= number) 577 number = PRIV(dev)->number + 1; 578 } 579 dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup); 580 if (!dev) 581 return -ENOMEM; 582 clip_priv = PRIV(dev); 583 sprintf(dev->name, "atm%d", number); 584 spin_lock_init(&clip_priv->xoff_lock); 585 clip_priv->number = number; 586 error = register_netdev(dev); 587 if (error) { 588 free_netdev(dev); 589 return error; 590 } 591 clip_priv->next = clip_devs; 592 clip_devs = dev; 593 pr_debug("registered (net:%s)\n", dev->name); 594 return number; 595 } 596 597 static int clip_device_event(struct notifier_block *this, unsigned long event, 598 void *arg) 599 { 600 struct net_device *dev = arg; 601 602 if (!net_eq(dev_net(dev), &init_net)) 603 return NOTIFY_DONE; 604 605 if (event == NETDEV_UNREGISTER) { 606 neigh_ifdown(&clip_tbl, dev); 607 return NOTIFY_DONE; 608 } 609 610 /* ignore non-CLIP devices */ 611 if (dev->type != ARPHRD_ATM || dev->netdev_ops != &clip_netdev_ops) 612 return NOTIFY_DONE; 613 614 switch (event) { 615 case NETDEV_UP: 616 pr_debug("NETDEV_UP\n"); 617 to_atmarpd(act_up, PRIV(dev)->number, 0); 618 break; 619 case NETDEV_GOING_DOWN: 620 pr_debug("NETDEV_DOWN\n"); 621 to_atmarpd(act_down, PRIV(dev)->number, 0); 622 break; 623 case NETDEV_CHANGE: 624 case NETDEV_CHANGEMTU: 625 pr_debug("NETDEV_CHANGE*\n"); 626 to_atmarpd(act_change, PRIV(dev)->number, 0); 627 break; 628 } 629 return NOTIFY_DONE; 630 } 631 632 static int clip_inet_event(struct notifier_block *this, unsigned long event, 633 void *ifa) 634 { 635 struct in_device *in_dev; 636 637 in_dev = ((struct in_ifaddr *)ifa)->ifa_dev; 638 /* 639 * Transitions are of the down-change-up type, so it's sufficient to 640 * handle the change on up. 641 */ 642 if (event != NETDEV_UP) 643 return NOTIFY_DONE; 644 return clip_device_event(this, NETDEV_CHANGE, in_dev->dev); 645 } 646 647 static struct notifier_block clip_dev_notifier = { 648 .notifier_call = clip_device_event, 649 }; 650 651 652 653 static struct notifier_block clip_inet_notifier = { 654 .notifier_call = clip_inet_event, 655 }; 656 657 658 659 static void atmarpd_close(struct atm_vcc *vcc) 660 { 661 pr_debug("\n"); 662 663 rtnl_lock(); 664 atmarpd = NULL; 665 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue); 666 rtnl_unlock(); 667 668 pr_debug("(done)\n"); 669 module_put(THIS_MODULE); 670 } 671 672 static struct atmdev_ops atmarpd_dev_ops = { 673 .close = atmarpd_close 674 }; 675 676 677 static struct atm_dev atmarpd_dev = { 678 .ops = &atmarpd_dev_ops, 679 .type = "arpd", 680 .number = 999, 681 .lock = __SPIN_LOCK_UNLOCKED(atmarpd_dev.lock) 682 }; 683 684 685 static int atm_init_atmarp(struct atm_vcc *vcc) 686 { 687 rtnl_lock(); 688 if (atmarpd) { 689 rtnl_unlock(); 690 return -EADDRINUSE; 691 } 692 693 mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ); 694 695 atmarpd = vcc; 696 set_bit(ATM_VF_META, &vcc->flags); 697 set_bit(ATM_VF_READY, &vcc->flags); 698 /* allow replies and avoid getting closed if signaling dies */ 699 vcc->dev = &atmarpd_dev; 700 vcc_insert_socket(sk_atm(vcc)); 701 vcc->push = NULL; 702 vcc->pop = NULL; /* crash */ 703 vcc->push_oam = NULL; /* crash */ 704 rtnl_unlock(); 705 return 0; 706 } 707 708 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 709 { 710 struct atm_vcc *vcc = ATM_SD(sock); 711 int err = 0; 712 713 switch (cmd) { 714 case SIOCMKCLIP: 715 case ATMARPD_CTRL: 716 case ATMARP_MKIP: 717 case ATMARP_SETENTRY: 718 case ATMARP_ENCAP: 719 if (!capable(CAP_NET_ADMIN)) 720 return -EPERM; 721 break; 722 default: 723 return -ENOIOCTLCMD; 724 } 725 726 switch (cmd) { 727 case SIOCMKCLIP: 728 err = clip_create(arg); 729 break; 730 case ATMARPD_CTRL: 731 err = atm_init_atmarp(vcc); 732 if (!err) { 733 sock->state = SS_CONNECTED; 734 __module_get(THIS_MODULE); 735 } 736 break; 737 case ATMARP_MKIP: 738 err = clip_mkip(vcc, arg); 739 break; 740 case ATMARP_SETENTRY: 741 err = clip_setentry(vcc, (__force __be32)arg); 742 break; 743 case ATMARP_ENCAP: 744 err = clip_encap(vcc, arg); 745 break; 746 } 747 return err; 748 } 749 750 static struct atm_ioctl clip_ioctl_ops = { 751 .owner = THIS_MODULE, 752 .ioctl = clip_ioctl, 753 }; 754 755 #ifdef CONFIG_PROC_FS 756 757 static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr) 758 { 759 static int code[] = { 1, 2, 10, 6, 1, 0 }; 760 static int e164[] = { 1, 8, 4, 6, 1, 0 }; 761 762 if (*addr->sas_addr.pub) { 763 seq_printf(seq, "%s", addr->sas_addr.pub); 764 if (*addr->sas_addr.prv) 765 seq_putc(seq, '+'); 766 } else if (!*addr->sas_addr.prv) { 767 seq_printf(seq, "%s", "(none)"); 768 return; 769 } 770 if (*addr->sas_addr.prv) { 771 unsigned char *prv = addr->sas_addr.prv; 772 int *fields; 773 int i, j; 774 775 fields = *prv == ATM_AFI_E164 ? e164 : code; 776 for (i = 0; fields[i]; i++) { 777 for (j = fields[i]; j; j--) 778 seq_printf(seq, "%02X", *prv++); 779 if (fields[i + 1]) 780 seq_putc(seq, '.'); 781 } 782 } 783 } 784 785 /* This means the neighbour entry has no attached VCC objects. */ 786 #define SEQ_NO_VCC_TOKEN ((void *) 2) 787 788 static void atmarp_info(struct seq_file *seq, struct net_device *dev, 789 struct atmarp_entry *entry, struct clip_vcc *clip_vcc) 790 { 791 unsigned long exp; 792 char buf[17]; 793 int svc, llc, off; 794 795 svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || 796 (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC)); 797 798 llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || clip_vcc->encap); 799 800 if (clip_vcc == SEQ_NO_VCC_TOKEN) 801 exp = entry->neigh->used; 802 else 803 exp = clip_vcc->last_use; 804 805 exp = (jiffies - exp) / HZ; 806 807 seq_printf(seq, "%-6s%-4s%-4s%5ld ", 808 dev->name, svc ? "SVC" : "PVC", llc ? "LLC" : "NULL", exp); 809 810 off = scnprintf(buf, sizeof(buf) - 1, "%pI4", 811 &entry->ip); 812 while (off < 16) 813 buf[off++] = ' '; 814 buf[off] = '\0'; 815 seq_printf(seq, "%s", buf); 816 817 if (clip_vcc == SEQ_NO_VCC_TOKEN) { 818 if (time_before(jiffies, entry->expires)) 819 seq_printf(seq, "(resolving)\n"); 820 else 821 seq_printf(seq, "(expired, ref %d)\n", 822 atomic_read(&entry->neigh->refcnt)); 823 } else if (!svc) { 824 seq_printf(seq, "%d.%d.%d\n", 825 clip_vcc->vcc->dev->number, 826 clip_vcc->vcc->vpi, clip_vcc->vcc->vci); 827 } else { 828 svc_addr(seq, &clip_vcc->vcc->remote); 829 seq_putc(seq, '\n'); 830 } 831 } 832 833 struct clip_seq_state { 834 /* This member must be first. */ 835 struct neigh_seq_state ns; 836 837 /* Local to clip specific iteration. */ 838 struct clip_vcc *vcc; 839 }; 840 841 static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e, 842 struct clip_vcc *curr) 843 { 844 if (!curr) { 845 curr = e->vccs; 846 if (!curr) 847 return SEQ_NO_VCC_TOKEN; 848 return curr; 849 } 850 if (curr == SEQ_NO_VCC_TOKEN) 851 return NULL; 852 853 curr = curr->next; 854 855 return curr; 856 } 857 858 static void *clip_seq_vcc_walk(struct clip_seq_state *state, 859 struct atmarp_entry *e, loff_t * pos) 860 { 861 struct clip_vcc *vcc = state->vcc; 862 863 vcc = clip_seq_next_vcc(e, vcc); 864 if (vcc && pos != NULL) { 865 while (*pos) { 866 vcc = clip_seq_next_vcc(e, vcc); 867 if (!vcc) 868 break; 869 --(*pos); 870 } 871 } 872 state->vcc = vcc; 873 874 return vcc; 875 } 876 877 static void *clip_seq_sub_iter(struct neigh_seq_state *_state, 878 struct neighbour *n, loff_t * pos) 879 { 880 struct clip_seq_state *state = (struct clip_seq_state *)_state; 881 882 return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos); 883 } 884 885 static void *clip_seq_start(struct seq_file *seq, loff_t * pos) 886 { 887 struct clip_seq_state *state = seq->private; 888 state->ns.neigh_sub_iter = clip_seq_sub_iter; 889 return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY); 890 } 891 892 static int clip_seq_show(struct seq_file *seq, void *v) 893 { 894 static char atm_arp_banner[] = 895 "IPitf TypeEncp Idle IP address ATM address\n"; 896 897 if (v == SEQ_START_TOKEN) { 898 seq_puts(seq, atm_arp_banner); 899 } else { 900 struct clip_seq_state *state = seq->private; 901 struct neighbour *n = v; 902 struct clip_vcc *vcc = state->vcc; 903 904 atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc); 905 } 906 return 0; 907 } 908 909 static const struct seq_operations arp_seq_ops = { 910 .start = clip_seq_start, 911 .next = neigh_seq_next, 912 .stop = neigh_seq_stop, 913 .show = clip_seq_show, 914 }; 915 916 static int arp_seq_open(struct inode *inode, struct file *file) 917 { 918 return seq_open_net(inode, file, &arp_seq_ops, 919 sizeof(struct clip_seq_state)); 920 } 921 922 static const struct file_operations arp_seq_fops = { 923 .open = arp_seq_open, 924 .read = seq_read, 925 .llseek = seq_lseek, 926 .release = seq_release_net, 927 .owner = THIS_MODULE 928 }; 929 #endif 930 931 static void atm_clip_exit_noproc(void); 932 933 static int __init atm_clip_init(void) 934 { 935 neigh_table_init_no_netlink(&clip_tbl); 936 937 clip_tbl_hook = &clip_tbl; 938 register_atm_ioctl(&clip_ioctl_ops); 939 register_netdevice_notifier(&clip_dev_notifier); 940 register_inetaddr_notifier(&clip_inet_notifier); 941 942 setup_timer(&idle_timer, idle_timer_check, 0); 943 944 #ifdef CONFIG_PROC_FS 945 { 946 struct proc_dir_entry *p; 947 948 p = proc_create("arp", S_IRUGO, atm_proc_root, &arp_seq_fops); 949 if (!p) { 950 pr_err("Unable to initialize /proc/net/atm/arp\n"); 951 atm_clip_exit_noproc(); 952 return -ENOMEM; 953 } 954 } 955 #endif 956 957 return 0; 958 } 959 960 static void atm_clip_exit_noproc(void) 961 { 962 struct net_device *dev, *next; 963 964 unregister_inetaddr_notifier(&clip_inet_notifier); 965 unregister_netdevice_notifier(&clip_dev_notifier); 966 967 deregister_atm_ioctl(&clip_ioctl_ops); 968 969 /* First, stop the idle timer, so it stops banging 970 * on the table. 971 */ 972 del_timer_sync(&idle_timer); 973 974 /* Next, purge the table, so that the device 975 * unregister loop below does not hang due to 976 * device references remaining in the table. 977 */ 978 neigh_ifdown(&clip_tbl, NULL); 979 980 dev = clip_devs; 981 while (dev) { 982 next = PRIV(dev)->next; 983 unregister_netdev(dev); 984 free_netdev(dev); 985 dev = next; 986 } 987 988 /* Now it is safe to fully shutdown whole table. */ 989 neigh_table_clear(&clip_tbl); 990 991 clip_tbl_hook = NULL; 992 } 993 994 static void __exit atm_clip_exit(void) 995 { 996 remove_proc_entry("arp", atm_proc_root); 997 998 atm_clip_exit_noproc(); 999 } 1000 1001 module_init(atm_clip_init); 1002 module_exit(atm_clip_exit); 1003 MODULE_AUTHOR("Werner Almesberger"); 1004 MODULE_DESCRIPTION("Classical/IP over ATM interface"); 1005 MODULE_LICENSE("GPL"); 1006