net/appletalk/ddp.c

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This source file includes following definitions.
__atalk_insert_socket
atalk_remove_socket
atalk_search_socket
atalk_find_or_insert_socket
atalk_destroy_timer
atalk_destroy_socket
atif_drop_device
atif_add_device
atif_probe_device
atif_proxy_probe_device
atalk_find_dev_addr
atalk_find_primary
atalk_find_anynet
atalk_find_interface
atrtr_find
atrtr_get_dev
atrtr_set_default
atrtr_create
atrtr_delete
atrtr_device_down
atalk_dev_down
ddp_device_event
atif_ioctl
atrtr_ioctl
atalk_sum_partial
atalk_sum_skb
atalk_checksum
atalk_create
atalk_release
atalk_pick_and_bind_port
atalk_autobind
atalk_bind
atalk_connect
atalk_getname
is_ip_over_ddp
handle_ip_over_ddp
atalk_route_packet
atalk_rcv
ltalk_rcv
atalk_sendmsg
atalk_recvmsg
atalk_ioctl
atalk_compat_ioctl
atalk_init
atalk_exit
   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      DDP:    An implementation of the AppleTalk DDP protocol for
   4  *              Ethernet 'ELAP'.
   5  *
   6  *              Alan Cox  <alan@lxorguk.ukuu.org.uk>
   7  *
   8  *              With more than a little assistance from
   9  *
  10  *              Wesley Craig <netatalk@umich.edu>
  11  *
  12  *      Fixes:
  13  *              Neil Horman             :       Added missing device ioctls
  14  *              Michael Callahan        :       Made routing work
  15  *              Wesley Craig            :       Fix probing to listen to a
  16  *                                              passed node id.
  17  *              Alan Cox                :       Added send/recvmsg support
  18  *              Alan Cox                :       Moved at. to protinfo in
  19  *                                              socket.
  20  *              Alan Cox                :       Added firewall hooks.
  21  *              Alan Cox                :       Supports new ARPHRD_LOOPBACK
  22  *              Christer Weinigel       :       Routing and /proc fixes.
  23  *              Bradford Johnson        :       LocalTalk.
  24  *              Tom Dyas                :       Module support.
  25  *              Alan Cox                :       Hooks for PPP (based on the
  26  *                                              LocalTalk hook).
  27  *              Alan Cox                :       Posix bits
  28  *              Alan Cox/Mike Freeman   :       Possible fix to NBP problems
  29  *              Bradford Johnson        :       IP-over-DDP (experimental)
  30  *              Jay Schulist            :       Moved IP-over-DDP to its own
  31  *                                              driver file. (ipddp.c & ipddp.h)
  32  *              Jay Schulist            :       Made work as module with
  33  *                                              AppleTalk drivers, cleaned it.
  34  *              Rob Newberry            :       Added proxy AARP and AARP
  35  *                                              procfs, moved probing to AARP
  36  *                                              module.
  37  *              Adrian Sun/
  38  *              Michael Zuelsdorff      :       fix for net.0 packets. don't
  39  *                                              allow illegal ether/tokentalk
  40  *                                              port assignment. we lose a
  41  *                                              valid localtalk port as a
  42  *                                              result.
  43  *              Arnaldo C. de Melo      :       Cleanup, in preparation for
  44  *                                              shared skb support 8)
  45  *              Arnaldo C. de Melo      :       Move proc stuff to atalk_proc.c,
  46  *                                              use seq_file
  47  */
  48 
  49 #include <linux/capability.h>
  50 #include <linux/module.h>
  51 #include <linux/if_arp.h>
  52 #include <linux/termios.h>      /* For TIOCOUTQ/INQ */
  53 #include <linux/compat.h>
  54 #include <linux/slab.h>
  55 #include <net/datalink.h>
  56 #include <net/psnap.h>
  57 #include <net/sock.h>
  58 #include <net/tcp_states.h>
  59 #include <net/route.h>
  60 #include <linux/atalk.h>
  61 #include <linux/highmem.h>
  62 
  63 struct datalink_proto *ddp_dl, *aarp_dl;
  64 static const struct proto_ops atalk_dgram_ops;
  65 
  66 /**************************************************************************\
  67 *                                                                          *
  68 * Handlers for the socket list.                                            *
  69 *                                                                          *
  70 \**************************************************************************/
  71 
  72 HLIST_HEAD(atalk_sockets);
  73 DEFINE_RWLOCK(atalk_sockets_lock);
  74 
  75 static inline void __atalk_insert_socket(struct sock *sk)
  76 {
  77         sk_add_node(sk, &atalk_sockets);
  78 }
  79 
  80 static inline void atalk_remove_socket(struct sock *sk)
  81 {
  82         write_lock_bh(&atalk_sockets_lock);
  83         sk_del_node_init(sk);
  84         write_unlock_bh(&atalk_sockets_lock);
  85 }
  86 
  87 static struct sock *atalk_search_socket(struct sockaddr_at *to,
  88                                         struct atalk_iface *atif)
  89 {
  90         struct sock *s;
  91 
  92         read_lock_bh(&atalk_sockets_lock);
  93         sk_for_each(s, &atalk_sockets) {
  94                 struct atalk_sock *at = at_sk(s);
  95 
  96                 if (to->sat_port != at->src_port)
  97                         continue;
  98 
  99                 if (to->sat_addr.s_net == ATADDR_ANYNET &&
 100                     to->sat_addr.s_node == ATADDR_BCAST)
 101                         goto found;
 102 
 103                 if (to->sat_addr.s_net == at->src_net &&
 104                     (to->sat_addr.s_node == at->src_node ||
 105                      to->sat_addr.s_node == ATADDR_BCAST ||
 106                      to->sat_addr.s_node == ATADDR_ANYNODE))
 107                         goto found;
 108 
 109                 /* XXXX.0 -- we got a request for this router. make sure
 110                  * that the node is appropriately set. */
 111                 if (to->sat_addr.s_node == ATADDR_ANYNODE &&
 112                     to->sat_addr.s_net != ATADDR_ANYNET &&
 113                     atif->address.s_node == at->src_node) {
 114                         to->sat_addr.s_node = atif->address.s_node;
 115                         goto found;
 116                 }
 117         }
 118         s = NULL;
 119 found:
 120         read_unlock_bh(&atalk_sockets_lock);
 121         return s;
 122 }
 123 
 124 /**
 125  * atalk_find_or_insert_socket - Try to find a socket matching ADDR
 126  * @sk: socket to insert in the list if it is not there already
 127  * @sat: address to search for
 128  *
 129  * Try to find a socket matching ADDR in the socket list, if found then return
 130  * it. If not, insert SK into the socket list.
 131  *
 132  * This entire operation must execute atomically.
 133  */
 134 static struct sock *atalk_find_or_insert_socket(struct sock *sk,
 135                                                 struct sockaddr_at *sat)
 136 {
 137         struct sock *s;
 138         struct atalk_sock *at;
 139 
 140         write_lock_bh(&atalk_sockets_lock);
 141         sk_for_each(s, &atalk_sockets) {
 142                 at = at_sk(s);
 143 
 144                 if (at->src_net == sat->sat_addr.s_net &&
 145                     at->src_node == sat->sat_addr.s_node &&
 146                     at->src_port == sat->sat_port)
 147                         goto found;
 148         }
 149         s = NULL;
 150         __atalk_insert_socket(sk); /* Wheee, it's free, assign and insert. */
 151 found:
 152         write_unlock_bh(&atalk_sockets_lock);
 153         return s;
 154 }
 155 
 156 static void atalk_destroy_timer(struct timer_list *t)
 157 {
 158         struct sock *sk = from_timer(sk, t, sk_timer);
 159 
 160         if (sk_has_allocations(sk)) {
 161                 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME;
 162                 add_timer(&sk->sk_timer);
 163         } else
 164                 sock_put(sk);
 165 }
 166 
 167 static inline void atalk_destroy_socket(struct sock *sk)
 168 {
 169         atalk_remove_socket(sk);
 170         skb_queue_purge(&sk->sk_receive_queue);
 171 
 172         if (sk_has_allocations(sk)) {
 173                 timer_setup(&sk->sk_timer, atalk_destroy_timer, 0);
 174                 sk->sk_timer.expires    = jiffies + SOCK_DESTROY_TIME;
 175                 add_timer(&sk->sk_timer);
 176         } else
 177                 sock_put(sk);
 178 }
 179 
 180 /**************************************************************************\
 181 *                                                                          *
 182 * Routing tables for the AppleTalk socket layer.                           *
 183 *                                                                          *
 184 \**************************************************************************/
 185 
 186 /* Anti-deadlock ordering is atalk_routes_lock --> iface_lock -DaveM */
 187 struct atalk_route *atalk_routes;
 188 DEFINE_RWLOCK(atalk_routes_lock);
 189 
 190 struct atalk_iface *atalk_interfaces;
 191 DEFINE_RWLOCK(atalk_interfaces_lock);
 192 
 193 /* For probing devices or in a routerless network */
 194 struct atalk_route atrtr_default;
 195 
 196 /* AppleTalk interface control */
 197 /*
 198  * Drop a device. Doesn't drop any of its routes - that is the caller's
 199  * problem. Called when we down the interface or delete the address.
 200  */
 201 static void atif_drop_device(struct net_device *dev)
 202 {
 203         struct atalk_iface **iface = &atalk_interfaces;
 204         struct atalk_iface *tmp;
 205 
 206         write_lock_bh(&atalk_interfaces_lock);
 207         while ((tmp = *iface) != NULL) {
 208                 if (tmp->dev == dev) {
 209                         *iface = tmp->next;
 210                         dev_put(dev);
 211                         kfree(tmp);
 212                         dev->atalk_ptr = NULL;
 213                 } else
 214                         iface = &tmp->next;
 215         }
 216         write_unlock_bh(&atalk_interfaces_lock);
 217 }
 218 
 219 static struct atalk_iface *atif_add_device(struct net_device *dev,
 220                                            struct atalk_addr *sa)
 221 {
 222         struct atalk_iface *iface = kzalloc(sizeof(*iface), GFP_KERNEL);
 223 
 224         if (!iface)
 225                 goto out;
 226 
 227         dev_hold(dev);
 228         iface->dev = dev;
 229         dev->atalk_ptr = iface;
 230         iface->address = *sa;
 231         iface->status = 0;
 232 
 233         write_lock_bh(&atalk_interfaces_lock);
 234         iface->next = atalk_interfaces;
 235         atalk_interfaces = iface;
 236         write_unlock_bh(&atalk_interfaces_lock);
 237 out:
 238         return iface;
 239 }
 240 
 241 /* Perform phase 2 AARP probing on our tentative address */
 242 static int atif_probe_device(struct atalk_iface *atif)
 243 {
 244         int netrange = ntohs(atif->nets.nr_lastnet) -
 245                         ntohs(atif->nets.nr_firstnet) + 1;
 246         int probe_net = ntohs(atif->address.s_net);
 247         int probe_node = atif->address.s_node;
 248         int netct, nodect;
 249 
 250         /* Offset the network we start probing with */
 251         if (probe_net == ATADDR_ANYNET) {
 252                 probe_net = ntohs(atif->nets.nr_firstnet);
 253                 if (netrange)
 254                         probe_net += jiffies % netrange;
 255         }
 256         if (probe_node == ATADDR_ANYNODE)
 257                 probe_node = jiffies & 0xFF;
 258 
 259         /* Scan the networks */
 260         atif->status |= ATIF_PROBE;
 261         for (netct = 0; netct <= netrange; netct++) {
 262                 /* Sweep the available nodes from a given start */
 263                 atif->address.s_net = htons(probe_net);
 264                 for (nodect = 0; nodect < 256; nodect++) {
 265                         atif->address.s_node = (nodect + probe_node) & 0xFF;
 266                         if (atif->address.s_node > 0 &&
 267                             atif->address.s_node < 254) {
 268                                 /* Probe a proposed address */
 269                                 aarp_probe_network(atif);
 270 
 271                                 if (!(atif->status & ATIF_PROBE_FAIL)) {
 272                                         atif->status &= ~ATIF_PROBE;
 273                                         return 0;
 274                                 }
 275                         }
 276                         atif->status &= ~ATIF_PROBE_FAIL;
 277                 }
 278                 probe_net++;
 279                 if (probe_net > ntohs(atif->nets.nr_lastnet))
 280                         probe_net = ntohs(atif->nets.nr_firstnet);
 281         }
 282         atif->status &= ~ATIF_PROBE;
 283 
 284         return -EADDRINUSE;     /* Network is full... */
 285 }
 286 
 287 
 288 /* Perform AARP probing for a proxy address */
 289 static int atif_proxy_probe_device(struct atalk_iface *atif,
 290                                    struct atalk_addr *proxy_addr)
 291 {
 292         int netrange = ntohs(atif->nets.nr_lastnet) -
 293                         ntohs(atif->nets.nr_firstnet) + 1;
 294         /* we probe the interface's network */
 295         int probe_net = ntohs(atif->address.s_net);
 296         int probe_node = ATADDR_ANYNODE;            /* we'll take anything */
 297         int netct, nodect;
 298 
 299         /* Offset the network we start probing with */
 300         if (probe_net == ATADDR_ANYNET) {
 301                 probe_net = ntohs(atif->nets.nr_firstnet);
 302                 if (netrange)
 303                         probe_net += jiffies % netrange;
 304         }
 305 
 306         if (probe_node == ATADDR_ANYNODE)
 307                 probe_node = jiffies & 0xFF;
 308 
 309         /* Scan the networks */
 310         for (netct = 0; netct <= netrange; netct++) {
 311                 /* Sweep the available nodes from a given start */
 312                 proxy_addr->s_net = htons(probe_net);
 313                 for (nodect = 0; nodect < 256; nodect++) {
 314                         proxy_addr->s_node = (nodect + probe_node) & 0xFF;
 315                         if (proxy_addr->s_node > 0 &&
 316                             proxy_addr->s_node < 254) {
 317                                 /* Tell AARP to probe a proposed address */
 318                                 int ret = aarp_proxy_probe_network(atif,
 319                                                                     proxy_addr);
 320 
 321                                 if (ret != -EADDRINUSE)
 322                                         return ret;
 323                         }
 324                 }
 325                 probe_net++;
 326                 if (probe_net > ntohs(atif->nets.nr_lastnet))
 327                         probe_net = ntohs(atif->nets.nr_firstnet);
 328         }
 329 
 330         return -EADDRINUSE;     /* Network is full... */
 331 }
 332 
 333 
 334 struct atalk_addr *atalk_find_dev_addr(struct net_device *dev)
 335 {
 336         struct atalk_iface *iface = dev->atalk_ptr;
 337         return iface ? &iface->address : NULL;
 338 }
 339 
 340 static struct atalk_addr *atalk_find_primary(void)
 341 {
 342         struct atalk_iface *fiface = NULL;
 343         struct atalk_addr *retval;
 344         struct atalk_iface *iface;
 345 
 346         /*
 347          * Return a point-to-point interface only if
 348          * there is no non-ptp interface available.
 349          */
 350         read_lock_bh(&atalk_interfaces_lock);
 351         for (iface = atalk_interfaces; iface; iface = iface->next) {
 352                 if (!fiface && !(iface->dev->flags & IFF_LOOPBACK))
 353                         fiface = iface;
 354                 if (!(iface->dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) {
 355                         retval = &iface->address;
 356                         goto out;
 357                 }
 358         }
 359 
 360         if (fiface)
 361                 retval = &fiface->address;
 362         else if (atalk_interfaces)
 363                 retval = &atalk_interfaces->address;
 364         else
 365                 retval = NULL;
 366 out:
 367         read_unlock_bh(&atalk_interfaces_lock);
 368         return retval;
 369 }
 370 
 371 /*
 372  * Find a match for 'any network' - ie any of our interfaces with that
 373  * node number will do just nicely.
 374  */
 375 static struct atalk_iface *atalk_find_anynet(int node, struct net_device *dev)
 376 {
 377         struct atalk_iface *iface = dev->atalk_ptr;
 378 
 379         if (!iface || iface->status & ATIF_PROBE)
 380                 goto out_err;
 381 
 382         if (node != ATADDR_BCAST &&
 383             iface->address.s_node != node &&
 384             node != ATADDR_ANYNODE)
 385                 goto out_err;
 386 out:
 387         return iface;
 388 out_err:
 389         iface = NULL;
 390         goto out;
 391 }
 392 
 393 /* Find a match for a specific network:node pair */
 394 static struct atalk_iface *atalk_find_interface(__be16 net, int node)
 395 {
 396         struct atalk_iface *iface;
 397 
 398         read_lock_bh(&atalk_interfaces_lock);
 399         for (iface = atalk_interfaces; iface; iface = iface->next) {
 400                 if ((node == ATADDR_BCAST ||
 401                      node == ATADDR_ANYNODE ||
 402                      iface->address.s_node == node) &&
 403                     iface->address.s_net == net &&
 404                     !(iface->status & ATIF_PROBE))
 405                         break;
 406 
 407                 /* XXXX.0 -- net.0 returns the iface associated with net */
 408                 if (node == ATADDR_ANYNODE && net != ATADDR_ANYNET &&
 409                     ntohs(iface->nets.nr_firstnet) <= ntohs(net) &&
 410                     ntohs(net) <= ntohs(iface->nets.nr_lastnet))
 411                         break;
 412         }
 413         read_unlock_bh(&atalk_interfaces_lock);
 414         return iface;
 415 }
 416 
 417 
 418 /*
 419  * Find a route for an AppleTalk packet. This ought to get cached in
 420  * the socket (later on...). We know about host routes and the fact
 421  * that a route must be direct to broadcast.
 422  */
 423 static struct atalk_route *atrtr_find(struct atalk_addr *target)
 424 {
 425         /*
 426          * we must search through all routes unless we find a
 427          * host route, because some host routes might overlap
 428          * network routes
 429          */
 430         struct atalk_route *net_route = NULL;
 431         struct atalk_route *r;
 432 
 433         read_lock_bh(&atalk_routes_lock);
 434         for (r = atalk_routes; r; r = r->next) {
 435                 if (!(r->flags & RTF_UP))
 436                         continue;
 437 
 438                 if (r->target.s_net == target->s_net) {
 439                         if (r->flags & RTF_HOST) {
 440                                 /*
 441                                  * if this host route is for the target,
 442                                  * the we're done
 443                                  */
 444                                 if (r->target.s_node == target->s_node)
 445                                         goto out;
 446                         } else
 447                                 /*
 448                                  * this route will work if there isn't a
 449                                  * direct host route, so cache it
 450                                  */
 451                                 net_route = r;
 452                 }
 453         }
 454 
 455         /*
 456          * if we found a network route but not a direct host
 457          * route, then return it
 458          */
 459         if (net_route)
 460                 r = net_route;
 461         else if (atrtr_default.dev)
 462                 r = &atrtr_default;
 463         else /* No route can be found */
 464                 r = NULL;
 465 out:
 466         read_unlock_bh(&atalk_routes_lock);
 467         return r;
 468 }
 469 
 470 
 471 /*
 472  * Given an AppleTalk network, find the device to use. This can be
 473  * a simple lookup.
 474  */
 475 struct net_device *atrtr_get_dev(struct atalk_addr *sa)
 476 {
 477         struct atalk_route *atr = atrtr_find(sa);
 478         return atr ? atr->dev : NULL;
 479 }
 480 
 481 /* Set up a default router */
 482 static void atrtr_set_default(struct net_device *dev)
 483 {
 484         atrtr_default.dev            = dev;
 485         atrtr_default.flags          = RTF_UP;
 486         atrtr_default.gateway.s_net  = htons(0);
 487         atrtr_default.gateway.s_node = 0;
 488 }
 489 
 490 /*
 491  * Add a router. Basically make sure it looks valid and stuff the
 492  * entry in the list. While it uses netranges we always set them to one
 493  * entry to work like netatalk.
 494  */
 495 static int atrtr_create(struct rtentry *r, struct net_device *devhint)
 496 {
 497         struct sockaddr_at *ta = (struct sockaddr_at *)&r->rt_dst;
 498         struct sockaddr_at *ga = (struct sockaddr_at *)&r->rt_gateway;
 499         struct atalk_route *rt;
 500         struct atalk_iface *iface, *riface;
 501         int retval = -EINVAL;
 502 
 503         /*
 504          * Fixme: Raise/Lower a routing change semaphore for these
 505          * operations.
 506          */
 507 
 508         /* Validate the request */
 509         if (ta->sat_family != AF_APPLETALK ||
 510             (!devhint && ga->sat_family != AF_APPLETALK))
 511                 goto out;
 512 
 513         /* Now walk the routing table and make our decisions */
 514         write_lock_bh(&atalk_routes_lock);
 515         for (rt = atalk_routes; rt; rt = rt->next) {
 516                 if (r->rt_flags != rt->flags)
 517                         continue;
 518 
 519                 if (ta->sat_addr.s_net == rt->target.s_net) {
 520                         if (!(rt->flags & RTF_HOST))
 521                                 break;
 522                         if (ta->sat_addr.s_node == rt->target.s_node)
 523                                 break;
 524                 }
 525         }
 526 
 527         if (!devhint) {
 528                 riface = NULL;
 529 
 530                 read_lock_bh(&atalk_interfaces_lock);
 531                 for (iface = atalk_interfaces; iface; iface = iface->next) {
 532                         if (!riface &&
 533                             ntohs(ga->sat_addr.s_net) >=
 534                                         ntohs(iface->nets.nr_firstnet) &&
 535                             ntohs(ga->sat_addr.s_net) <=
 536                                         ntohs(iface->nets.nr_lastnet))
 537                                 riface = iface;
 538 
 539                         if (ga->sat_addr.s_net == iface->address.s_net &&
 540                             ga->sat_addr.s_node == iface->address.s_node)
 541                                 riface = iface;
 542                 }
 543                 read_unlock_bh(&atalk_interfaces_lock);
 544 
 545                 retval = -ENETUNREACH;
 546                 if (!riface)
 547                         goto out_unlock;
 548 
 549                 devhint = riface->dev;
 550         }
 551 
 552         if (!rt) {
 553                 rt = kzalloc(sizeof(*rt), GFP_ATOMIC);
 554 
 555                 retval = -ENOBUFS;
 556                 if (!rt)
 557                         goto out_unlock;
 558 
 559                 rt->next = atalk_routes;
 560                 atalk_routes = rt;
 561         }
 562 
 563         /* Fill in the routing entry */
 564         rt->target  = ta->sat_addr;
 565         dev_hold(devhint);
 566         rt->dev     = devhint;
 567         rt->flags   = r->rt_flags;
 568         rt->gateway = ga->sat_addr;
 569 
 570         retval = 0;
 571 out_unlock:
 572         write_unlock_bh(&atalk_routes_lock);
 573 out:
 574         return retval;
 575 }
 576 
 577 /* Delete a route. Find it and discard it */
 578 static int atrtr_delete(struct atalk_addr *addr)
 579 {
 580         struct atalk_route **r = &atalk_routes;
 581         int retval = 0;
 582         struct atalk_route *tmp;
 583 
 584         write_lock_bh(&atalk_routes_lock);
 585         while ((tmp = *r) != NULL) {
 586                 if (tmp->target.s_net == addr->s_net &&
 587                     (!(tmp->flags&RTF_GATEWAY) ||
 588                      tmp->target.s_node == addr->s_node)) {
 589                         *r = tmp->next;
 590                         dev_put(tmp->dev);
 591                         kfree(tmp);
 592                         goto out;
 593                 }
 594                 r = &tmp->next;
 595         }
 596         retval = -ENOENT;
 597 out:
 598         write_unlock_bh(&atalk_routes_lock);
 599         return retval;
 600 }
 601 
 602 /*
 603  * Called when a device is downed. Just throw away any routes
 604  * via it.
 605  */
 606 static void atrtr_device_down(struct net_device *dev)
 607 {
 608         struct atalk_route **r = &atalk_routes;
 609         struct atalk_route *tmp;
 610 
 611         write_lock_bh(&atalk_routes_lock);
 612         while ((tmp = *r) != NULL) {
 613                 if (tmp->dev == dev) {
 614                         *r = tmp->next;
 615                         dev_put(dev);
 616                         kfree(tmp);
 617                 } else
 618                         r = &tmp->next;
 619         }
 620         write_unlock_bh(&atalk_routes_lock);
 621 
 622         if (atrtr_default.dev == dev)
 623                 atrtr_set_default(NULL);
 624 }
 625 
 626 /* Actually down the interface */
 627 static inline void atalk_dev_down(struct net_device *dev)
 628 {
 629         atrtr_device_down(dev); /* Remove all routes for the device */
 630         aarp_device_down(dev);  /* Remove AARP entries for the device */
 631         atif_drop_device(dev);  /* Remove the device */
 632 }
 633 
 634 /*
 635  * A device event has occurred. Watch for devices going down and
 636  * delete our use of them (iface and route).
 637  */
 638 static int ddp_device_event(struct notifier_block *this, unsigned long event,
 639                             void *ptr)
 640 {
 641         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 642 
 643         if (!net_eq(dev_net(dev), &init_net))
 644                 return NOTIFY_DONE;
 645 
 646         if (event == NETDEV_DOWN)
 647                 /* Discard any use of this */
 648                 atalk_dev_down(dev);
 649 
 650         return NOTIFY_DONE;
 651 }
 652 
 653 /* ioctl calls. Shouldn't even need touching */
 654 /* Device configuration ioctl calls */
 655 static int atif_ioctl(int cmd, void __user *arg)
 656 {
 657         static char aarp_mcast[6] = { 0x09, 0x00, 0x00, 0xFF, 0xFF, 0xFF };
 658         struct ifreq atreq;
 659         struct atalk_netrange *nr;
 660         struct sockaddr_at *sa;
 661         struct net_device *dev;
 662         struct atalk_iface *atif;
 663         int ct;
 664         int limit;
 665         struct rtentry rtdef;
 666         int add_route;
 667 
 668         if (copy_from_user(&atreq, arg, sizeof(atreq)))
 669                 return -EFAULT;
 670 
 671         dev = __dev_get_by_name(&init_net, atreq.ifr_name);
 672         if (!dev)
 673                 return -ENODEV;
 674 
 675         sa = (struct sockaddr_at *)&atreq.ifr_addr;
 676         atif = atalk_find_dev(dev);
 677 
 678         switch (cmd) {
 679         case SIOCSIFADDR:
 680                 if (!capable(CAP_NET_ADMIN))
 681                         return -EPERM;
 682                 if (sa->sat_family != AF_APPLETALK)
 683                         return -EINVAL;
 684                 if (dev->type != ARPHRD_ETHER &&
 685                     dev->type != ARPHRD_LOOPBACK &&
 686                     dev->type != ARPHRD_LOCALTLK &&
 687                     dev->type != ARPHRD_PPP)
 688                         return -EPROTONOSUPPORT;
 689 
 690                 nr = (struct atalk_netrange *)&sa->sat_zero[0];
 691                 add_route = 1;
 692 
 693                 /*
 694                  * if this is a point-to-point iface, and we already
 695                  * have an iface for this AppleTalk address, then we
 696                  * should not add a route
 697                  */
 698                 if ((dev->flags & IFF_POINTOPOINT) &&
 699                     atalk_find_interface(sa->sat_addr.s_net,
 700                                          sa->sat_addr.s_node)) {
 701                         printk(KERN_DEBUG "AppleTalk: point-to-point "
 702                                "interface added with "
 703                                "existing address\n");
 704                         add_route = 0;
 705                 }
 706 
 707                 /*
 708                  * Phase 1 is fine on LocalTalk but we don't do
 709                  * EtherTalk phase 1. Anyone wanting to add it go ahead.
 710                  */
 711                 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2)
 712                         return -EPROTONOSUPPORT;
 713                 if (sa->sat_addr.s_node == ATADDR_BCAST ||
 714                     sa->sat_addr.s_node == 254)
 715                         return -EINVAL;
 716                 if (atif) {
 717                         /* Already setting address */
 718                         if (atif->status & ATIF_PROBE)
 719                                 return -EBUSY;
 720 
 721                         atif->address.s_net  = sa->sat_addr.s_net;
 722                         atif->address.s_node = sa->sat_addr.s_node;
 723                         atrtr_device_down(dev); /* Flush old routes */
 724                 } else {
 725                         atif = atif_add_device(dev, &sa->sat_addr);
 726                         if (!atif)
 727                                 return -ENOMEM;
 728                 }
 729                 atif->nets = *nr;
 730 
 731                 /*
 732                  * Check if the chosen address is used. If so we
 733                  * error and atalkd will try another.
 734                  */
 735 
 736                 if (!(dev->flags & IFF_LOOPBACK) &&
 737                     !(dev->flags & IFF_POINTOPOINT) &&
 738                     atif_probe_device(atif) < 0) {
 739                         atif_drop_device(dev);
 740                         return -EADDRINUSE;
 741                 }
 742 
 743                 /* Hey it worked - add the direct routes */
 744                 sa = (struct sockaddr_at *)&rtdef.rt_gateway;
 745                 sa->sat_family = AF_APPLETALK;
 746                 sa->sat_addr.s_net  = atif->address.s_net;
 747                 sa->sat_addr.s_node = atif->address.s_node;
 748                 sa = (struct sockaddr_at *)&rtdef.rt_dst;
 749                 rtdef.rt_flags = RTF_UP;
 750                 sa->sat_family = AF_APPLETALK;
 751                 sa->sat_addr.s_node = ATADDR_ANYNODE;
 752                 if (dev->flags & IFF_LOOPBACK ||
 753                     dev->flags & IFF_POINTOPOINT)
 754                         rtdef.rt_flags |= RTF_HOST;
 755 
 756                 /* Routerless initial state */
 757                 if (nr->nr_firstnet == htons(0) &&
 758                     nr->nr_lastnet == htons(0xFFFE)) {
 759                         sa->sat_addr.s_net = atif->address.s_net;
 760                         atrtr_create(&rtdef, dev);
 761                         atrtr_set_default(dev);
 762                 } else {
 763                         limit = ntohs(nr->nr_lastnet);
 764                         if (limit - ntohs(nr->nr_firstnet) > 4096) {
 765                                 printk(KERN_WARNING "Too many routes/"
 766                                        "iface.\n");
 767                                 return -EINVAL;
 768                         }
 769                         if (add_route)
 770                                 for (ct = ntohs(nr->nr_firstnet);
 771                                      ct <= limit; ct++) {
 772                                         sa->sat_addr.s_net = htons(ct);
 773                                         atrtr_create(&rtdef, dev);
 774                                 }
 775                 }
 776                 dev_mc_add_global(dev, aarp_mcast);
 777                 return 0;
 778 
 779         case SIOCGIFADDR:
 780                 if (!atif)
 781                         return -EADDRNOTAVAIL;
 782 
 783                 sa->sat_family = AF_APPLETALK;
 784                 sa->sat_addr = atif->address;
 785                 break;
 786 
 787         case SIOCGIFBRDADDR:
 788                 if (!atif)
 789                         return -EADDRNOTAVAIL;
 790 
 791                 sa->sat_family = AF_APPLETALK;
 792                 sa->sat_addr.s_net = atif->address.s_net;
 793                 sa->sat_addr.s_node = ATADDR_BCAST;
 794                 break;
 795 
 796         case SIOCATALKDIFADDR:
 797         case SIOCDIFADDR:
 798                 if (!capable(CAP_NET_ADMIN))
 799                         return -EPERM;
 800                 if (sa->sat_family != AF_APPLETALK)
 801                         return -EINVAL;
 802                 atalk_dev_down(dev);
 803                 break;
 804 
 805         case SIOCSARP:
 806                 if (!capable(CAP_NET_ADMIN))
 807                         return -EPERM;
 808                 if (sa->sat_family != AF_APPLETALK)
 809                         return -EINVAL;
 810                 /*
 811                  * for now, we only support proxy AARP on ELAP;
 812                  * we should be able to do it for LocalTalk, too.
 813                  */
 814                 if (dev->type != ARPHRD_ETHER)
 815                         return -EPROTONOSUPPORT;
 816 
 817                 /*
 818                  * atif points to the current interface on this network;
 819                  * we aren't concerned about its current status (at
 820                  * least for now), but it has all the settings about
 821                  * the network we're going to probe. Consequently, it
 822                  * must exist.
 823                  */
 824                 if (!atif)
 825                         return -EADDRNOTAVAIL;
 826 
 827                 nr = (struct atalk_netrange *)&(atif->nets);
 828                 /*
 829                  * Phase 1 is fine on Localtalk but we don't do
 830                  * Ethertalk phase 1. Anyone wanting to add it go ahead.
 831                  */
 832                 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2)
 833                         return -EPROTONOSUPPORT;
 834 
 835                 if (sa->sat_addr.s_node == ATADDR_BCAST ||
 836                     sa->sat_addr.s_node == 254)
 837                         return -EINVAL;
 838 
 839                 /*
 840                  * Check if the chosen address is used. If so we
 841                  * error and ATCP will try another.
 842                  */
 843                 if (atif_proxy_probe_device(atif, &(sa->sat_addr)) < 0)
 844                         return -EADDRINUSE;
 845 
 846                 /*
 847                  * We now have an address on the local network, and
 848                  * the AARP code will defend it for us until we take it
 849                  * down. We don't set up any routes right now, because
 850                  * ATCP will install them manually via SIOCADDRT.
 851                  */
 852                 break;
 853 
 854         case SIOCDARP:
 855                 if (!capable(CAP_NET_ADMIN))
 856                         return -EPERM;
 857                 if (sa->sat_family != AF_APPLETALK)
 858                         return -EINVAL;
 859                 if (!atif)
 860                         return -EADDRNOTAVAIL;
 861 
 862                 /* give to aarp module to remove proxy entry */
 863                 aarp_proxy_remove(atif->dev, &(sa->sat_addr));
 864                 return 0;
 865         }
 866 
 867         return copy_to_user(arg, &atreq, sizeof(atreq)) ? -EFAULT : 0;
 868 }
 869 
 870 /* Routing ioctl() calls */
 871 static int atrtr_ioctl(unsigned int cmd, void __user *arg)
 872 {
 873         struct rtentry rt;
 874 
 875         if (copy_from_user(&rt, arg, sizeof(rt)))
 876                 return -EFAULT;
 877 
 878         switch (cmd) {
 879         case SIOCDELRT:
 880                 if (rt.rt_dst.sa_family != AF_APPLETALK)
 881                         return -EINVAL;
 882                 return atrtr_delete(&((struct sockaddr_at *)
 883                                       &rt.rt_dst)->sat_addr);
 884 
 885         case SIOCADDRT: {
 886                 struct net_device *dev = NULL;
 887                 if (rt.rt_dev) {
 888                         char name[IFNAMSIZ];
 889                         if (copy_from_user(name, rt.rt_dev, IFNAMSIZ-1))
 890                                 return -EFAULT;
 891                         name[IFNAMSIZ-1] = '\0';
 892                         dev = __dev_get_by_name(&init_net, name);
 893                         if (!dev)
 894                                 return -ENODEV;
 895                 }
 896                 return atrtr_create(&rt, dev);
 897         }
 898         }
 899         return -EINVAL;
 900 }
 901 
 902 /**************************************************************************\
 903 *                                                                          *
 904 * Handling for system calls applied via the various interfaces to an       *
 905 * AppleTalk socket object.                                                 *
 906 *                                                                          *
 907 \**************************************************************************/
 908 
 909 /*
 910  * Checksum: This is 'optional'. It's quite likely also a good
 911  * candidate for assembler hackery 8)
 912  */
 913 static unsigned long atalk_sum_partial(const unsigned char *data,
 914                                        int len, unsigned long sum)
 915 {
 916         /* This ought to be unwrapped neatly. I'll trust gcc for now */
 917         while (len--) {
 918                 sum += *data++;
 919                 sum = rol16(sum, 1);
 920         }
 921         return sum;
 922 }
 923 
 924 /*  Checksum skb data --  similar to skb_checksum  */
 925 static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset,
 926                                    int len, unsigned long sum)
 927 {
 928         int start = skb_headlen(skb);
 929         struct sk_buff *frag_iter;
 930         int i, copy;
 931 
 932         /* checksum stuff in header space */
 933         if ((copy = start - offset) > 0) {
 934                 if (copy > len)
 935                         copy = len;
 936                 sum = atalk_sum_partial(skb->data + offset, copy, sum);
 937                 if ((len -= copy) == 0)
 938                         return sum;
 939 
 940                 offset += copy;
 941         }
 942 
 943         /* checksum stuff in frags */
 944         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 945                 int end;
 946                 const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 947                 WARN_ON(start > offset + len);
 948 
 949                 end = start + skb_frag_size(frag);
 950                 if ((copy = end - offset) > 0) {
 951                         u8 *vaddr;
 952 
 953                         if (copy > len)
 954                                 copy = len;
 955                         vaddr = kmap_atomic(skb_frag_page(frag));
 956                         sum = atalk_sum_partial(vaddr + skb_frag_off(frag) +
 957                                                 offset - start, copy, sum);
 958                         kunmap_atomic(vaddr);
 959 
 960                         if (!(len -= copy))
 961                                 return sum;
 962                         offset += copy;
 963                 }
 964                 start = end;
 965         }
 966 
 967         skb_walk_frags(skb, frag_iter) {
 968                 int end;
 969 
 970                 WARN_ON(start > offset + len);
 971 
 972                 end = start + frag_iter->len;
 973                 if ((copy = end - offset) > 0) {
 974                         if (copy > len)
 975                                 copy = len;
 976                         sum = atalk_sum_skb(frag_iter, offset - start,
 977                                             copy, sum);
 978                         if ((len -= copy) == 0)
 979                                 return sum;
 980                         offset += copy;
 981                 }
 982                 start = end;
 983         }
 984 
 985         BUG_ON(len > 0);
 986 
 987         return sum;
 988 }
 989 
 990 static __be16 atalk_checksum(const struct sk_buff *skb, int len)
 991 {
 992         unsigned long sum;
 993 
 994         /* skip header 4 bytes */
 995         sum = atalk_sum_skb(skb, 4, len-4, 0);
 996 
 997         /* Use 0xFFFF for 0. 0 itself means none */
 998         return sum ? htons((unsigned short)sum) : htons(0xFFFF);
 999 }
1000 
1001 static struct proto ddp_proto = {
1002         .name     = "DDP",
1003         .owner    = THIS_MODULE,
1004         .obj_size = sizeof(struct atalk_sock),
1005 };
1006 
1007 /*
1008  * Create a socket. Initialise the socket, blank the addresses
1009  * set the state.
1010  */
1011 static int atalk_create(struct net *net, struct socket *sock, int protocol,
1012                         int kern)
1013 {
1014         struct sock *sk;
1015         int rc = -ESOCKTNOSUPPORT;
1016 
1017         if (!net_eq(net, &init_net))
1018                 return -EAFNOSUPPORT;
1019 
1020         /*
1021          * We permit SOCK_DGRAM and RAW is an extension. It is trivial to do
1022          * and gives you the full ELAP frame. Should be handy for CAP 8)
1023          */
1024         if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
1025                 goto out;
1026 
1027         rc = -EPERM;
1028         if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
1029                 goto out;
1030 
1031         rc = -ENOMEM;
1032         sk = sk_alloc(net, PF_APPLETALK, GFP_KERNEL, &ddp_proto, kern);
1033         if (!sk)
1034                 goto out;
1035         rc = 0;
1036         sock->ops = &atalk_dgram_ops;
1037         sock_init_data(sock, sk);
1038 
1039         /* Checksums on by default */
1040         sock_set_flag(sk, SOCK_ZAPPED);
1041 out:
1042         return rc;
1043 }
1044 
1045 /* Free a socket. No work needed */
1046 static int atalk_release(struct socket *sock)
1047 {
1048         struct sock *sk = sock->sk;
1049 
1050         if (sk) {
1051                 sock_hold(sk);
1052                 lock_sock(sk);
1053 
1054                 sock_orphan(sk);
1055                 sock->sk = NULL;
1056                 atalk_destroy_socket(sk);
1057 
1058                 release_sock(sk);
1059                 sock_put(sk);
1060         }
1061         return 0;
1062 }
1063 
1064 /**
1065  * atalk_pick_and_bind_port - Pick a source port when one is not given
1066  * @sk: socket to insert into the tables
1067  * @sat: address to search for
1068  *
1069  * Pick a source port when one is not given. If we can find a suitable free
1070  * one, we insert the socket into the tables using it.
1071  *
1072  * This whole operation must be atomic.
1073  */
1074 static int atalk_pick_and_bind_port(struct sock *sk, struct sockaddr_at *sat)
1075 {
1076         int retval;
1077 
1078         write_lock_bh(&atalk_sockets_lock);
1079 
1080         for (sat->sat_port = ATPORT_RESERVED;
1081              sat->sat_port < ATPORT_LAST;
1082              sat->sat_port++) {
1083                 struct sock *s;
1084 
1085                 sk_for_each(s, &atalk_sockets) {
1086                         struct atalk_sock *at = at_sk(s);
1087 
1088                         if (at->src_net == sat->sat_addr.s_net &&
1089                             at->src_node == sat->sat_addr.s_node &&
1090                             at->src_port == sat->sat_port)
1091                                 goto try_next_port;
1092                 }
1093 
1094                 /* Wheee, it's free, assign and insert. */
1095                 __atalk_insert_socket(sk);
1096                 at_sk(sk)->src_port = sat->sat_port;
1097                 retval = 0;
1098                 goto out;
1099 
1100 try_next_port:;
1101         }
1102 
1103         retval = -EBUSY;
1104 out:
1105         write_unlock_bh(&atalk_sockets_lock);
1106         return retval;
1107 }
1108 
1109 static int atalk_autobind(struct sock *sk)
1110 {
1111         struct atalk_sock *at = at_sk(sk);
1112         struct sockaddr_at sat;
1113         struct atalk_addr *ap = atalk_find_primary();
1114         int n = -EADDRNOTAVAIL;
1115 
1116         if (!ap || ap->s_net == htons(ATADDR_ANYNET))
1117                 goto out;
1118 
1119         at->src_net  = sat.sat_addr.s_net  = ap->s_net;
1120         at->src_node = sat.sat_addr.s_node = ap->s_node;
1121 
1122         n = atalk_pick_and_bind_port(sk, &sat);
1123         if (!n)
1124                 sock_reset_flag(sk, SOCK_ZAPPED);
1125 out:
1126         return n;
1127 }
1128 
1129 /* Set the address 'our end' of the connection */
1130 static int atalk_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
1131 {
1132         struct sockaddr_at *addr = (struct sockaddr_at *)uaddr;
1133         struct sock *sk = sock->sk;
1134         struct atalk_sock *at = at_sk(sk);
1135         int err;
1136 
1137         if (!sock_flag(sk, SOCK_ZAPPED) ||
1138             addr_len != sizeof(struct sockaddr_at))
1139                 return -EINVAL;
1140 
1141         if (addr->sat_family != AF_APPLETALK)
1142                 return -EAFNOSUPPORT;
1143 
1144         lock_sock(sk);
1145         if (addr->sat_addr.s_net == htons(ATADDR_ANYNET)) {
1146                 struct atalk_addr *ap = atalk_find_primary();
1147 
1148                 err = -EADDRNOTAVAIL;
1149                 if (!ap)
1150                         goto out;
1151 
1152                 at->src_net  = addr->sat_addr.s_net = ap->s_net;
1153                 at->src_node = addr->sat_addr.s_node = ap->s_node;
1154         } else {
1155                 err = -EADDRNOTAVAIL;
1156                 if (!atalk_find_interface(addr->sat_addr.s_net,
1157                                           addr->sat_addr.s_node))
1158                         goto out;
1159 
1160                 at->src_net  = addr->sat_addr.s_net;
1161                 at->src_node = addr->sat_addr.s_node;
1162         }
1163 
1164         if (addr->sat_port == ATADDR_ANYPORT) {
1165                 err = atalk_pick_and_bind_port(sk, addr);
1166 
1167                 if (err < 0)
1168                         goto out;
1169         } else {
1170                 at->src_port = addr->sat_port;
1171 
1172                 err = -EADDRINUSE;
1173                 if (atalk_find_or_insert_socket(sk, addr))
1174                         goto out;
1175         }
1176 
1177         sock_reset_flag(sk, SOCK_ZAPPED);
1178         err = 0;
1179 out:
1180         release_sock(sk);
1181         return err;
1182 }
1183 
1184 /* Set the address we talk to */
1185 static int atalk_connect(struct socket *sock, struct sockaddr *uaddr,
1186                          int addr_len, int flags)
1187 {
1188         struct sock *sk = sock->sk;
1189         struct atalk_sock *at = at_sk(sk);
1190         struct sockaddr_at *addr;
1191         int err;
1192 
1193         sk->sk_state   = TCP_CLOSE;
1194         sock->state = SS_UNCONNECTED;
1195 
1196         if (addr_len != sizeof(*addr))
1197                 return -EINVAL;
1198 
1199         addr = (struct sockaddr_at *)uaddr;
1200 
1201         if (addr->sat_family != AF_APPLETALK)
1202                 return -EAFNOSUPPORT;
1203 
1204         if (addr->sat_addr.s_node == ATADDR_BCAST &&
1205             !sock_flag(sk, SOCK_BROADCAST)) {
1206 #if 1
1207                 pr_warn("atalk_connect: %s is broken and did not set SO_BROADCAST.\n",
1208                         current->comm);
1209 #else
1210                 return -EACCES;
1211 #endif
1212         }
1213 
1214         lock_sock(sk);
1215         err = -EBUSY;
1216         if (sock_flag(sk, SOCK_ZAPPED))
1217                 if (atalk_autobind(sk) < 0)
1218                         goto out;
1219 
1220         err = -ENETUNREACH;
1221         if (!atrtr_get_dev(&addr->sat_addr))
1222                 goto out;
1223 
1224         at->dest_port = addr->sat_port;
1225         at->dest_net  = addr->sat_addr.s_net;
1226         at->dest_node = addr->sat_addr.s_node;
1227 
1228         sock->state  = SS_CONNECTED;
1229         sk->sk_state = TCP_ESTABLISHED;
1230         err = 0;
1231 out:
1232         release_sock(sk);
1233         return err;
1234 }
1235 
1236 /*
1237  * Find the name of an AppleTalk socket. Just copy the right
1238  * fields into the sockaddr.
1239  */
1240 static int atalk_getname(struct socket *sock, struct sockaddr *uaddr,
1241                          int peer)
1242 {
1243         struct sockaddr_at sat;
1244         struct sock *sk = sock->sk;
1245         struct atalk_sock *at = at_sk(sk);
1246         int err;
1247 
1248         lock_sock(sk);
1249         err = -ENOBUFS;
1250         if (sock_flag(sk, SOCK_ZAPPED))
1251                 if (atalk_autobind(sk) < 0)
1252                         goto out;
1253 
1254         memset(&sat, 0, sizeof(sat));
1255 
1256         if (peer) {
1257                 err = -ENOTCONN;
1258                 if (sk->sk_state != TCP_ESTABLISHED)
1259                         goto out;
1260 
1261                 sat.sat_addr.s_net  = at->dest_net;
1262                 sat.sat_addr.s_node = at->dest_node;
1263                 sat.sat_port        = at->dest_port;
1264         } else {
1265                 sat.sat_addr.s_net  = at->src_net;
1266                 sat.sat_addr.s_node = at->src_node;
1267                 sat.sat_port        = at->src_port;
1268         }
1269 
1270         sat.sat_family = AF_APPLETALK;
1271         memcpy(uaddr, &sat, sizeof(sat));
1272         err = sizeof(struct sockaddr_at);
1273 
1274 out:
1275         release_sock(sk);
1276         return err;
1277 }
1278 
1279 #if IS_ENABLED(CONFIG_IPDDP)
1280 static __inline__ int is_ip_over_ddp(struct sk_buff *skb)
1281 {
1282         return skb->data[12] == 22;
1283 }
1284 
1285 static int handle_ip_over_ddp(struct sk_buff *skb)
1286 {
1287         struct net_device *dev = __dev_get_by_name(&init_net, "ipddp0");
1288         struct net_device_stats *stats;
1289 
1290         /* This needs to be able to handle ipddp"N" devices */
1291         if (!dev) {
1292                 kfree_skb(skb);
1293                 return NET_RX_DROP;
1294         }
1295 
1296         skb->protocol = htons(ETH_P_IP);
1297         skb_pull(skb, 13);
1298         skb->dev   = dev;
1299         skb_reset_transport_header(skb);
1300 
1301         stats = netdev_priv(dev);
1302         stats->rx_packets++;
1303         stats->rx_bytes += skb->len + 13;
1304         return netif_rx(skb);  /* Send the SKB up to a higher place. */
1305 }
1306 #else
1307 /* make it easy for gcc to optimize this test out, i.e. kill the code */
1308 #define is_ip_over_ddp(skb) 0
1309 #define handle_ip_over_ddp(skb) 0
1310 #endif
1311 
1312 static int atalk_route_packet(struct sk_buff *skb, struct net_device *dev,
1313                               struct ddpehdr *ddp, __u16 len_hops, int origlen)
1314 {
1315         struct atalk_route *rt;
1316         struct atalk_addr ta;
1317 
1318         /*
1319          * Don't route multicast, etc., packets, or packets sent to "this
1320          * network"
1321          */
1322         if (skb->pkt_type != PACKET_HOST || !ddp->deh_dnet) {
1323                 /*
1324                  * FIXME:
1325                  *
1326                  * Can it ever happen that a packet is from a PPP iface and
1327                  * needs to be broadcast onto the default network?
1328                  */
1329                 if (dev->type == ARPHRD_PPP)
1330                         printk(KERN_DEBUG "AppleTalk: didn't forward broadcast "
1331                                           "packet received from PPP iface\n");
1332                 goto free_it;
1333         }
1334 
1335         ta.s_net  = ddp->deh_dnet;
1336         ta.s_node = ddp->deh_dnode;
1337 
1338         /* Route the packet */
1339         rt = atrtr_find(&ta);
1340         /* increment hops count */
1341         len_hops += 1 << 10;
1342         if (!rt || !(len_hops & (15 << 10)))
1343                 goto free_it;
1344 
1345         /* FIXME: use skb->cb to be able to use shared skbs */
1346 
1347         /*
1348          * Route goes through another gateway, so set the target to the
1349          * gateway instead.
1350          */
1351 
1352         if (rt->flags & RTF_GATEWAY) {
1353                 ta.s_net  = rt->gateway.s_net;
1354                 ta.s_node = rt->gateway.s_node;
1355         }
1356 
1357         /* Fix up skb->len field */
1358         skb_trim(skb, min_t(unsigned int, origlen,
1359                             (rt->dev->hard_header_len +
1360                              ddp_dl->header_length + (len_hops & 1023))));
1361 
1362         /* FIXME: use skb->cb to be able to use shared skbs */
1363         ddp->deh_len_hops = htons(len_hops);
1364 
1365         /*
1366          * Send the buffer onwards
1367          *
1368          * Now we must always be careful. If it's come from LocalTalk to
1369          * EtherTalk it might not fit
1370          *
1371          * Order matters here: If a packet has to be copied to make a new
1372          * headroom (rare hopefully) then it won't need unsharing.
1373          *
1374          * Note. ddp-> becomes invalid at the realloc.
1375          */
1376         if (skb_headroom(skb) < 22) {
1377                 /* 22 bytes - 12 ether, 2 len, 3 802.2 5 snap */
1378                 struct sk_buff *nskb = skb_realloc_headroom(skb, 32);
1379                 kfree_skb(skb);
1380                 skb = nskb;
1381         } else
1382                 skb = skb_unshare(skb, GFP_ATOMIC);
1383 
1384         /*
1385          * If the buffer didn't vanish into the lack of space bitbucket we can
1386          * send it.
1387          */
1388         if (skb == NULL)
1389                 goto drop;
1390 
1391         if (aarp_send_ddp(rt->dev, skb, &ta, NULL) == NET_XMIT_DROP)
1392                 return NET_RX_DROP;
1393         return NET_RX_SUCCESS;
1394 free_it:
1395         kfree_skb(skb);
1396 drop:
1397         return NET_RX_DROP;
1398 }
1399 
1400 /**
1401  *      atalk_rcv - Receive a packet (in skb) from device dev
1402  *      @skb - packet received
1403  *      @dev - network device where the packet comes from
1404  *      @pt - packet type
1405  *
1406  *      Receive a packet (in skb) from device dev. This has come from the SNAP
1407  *      decoder, and on entry skb->transport_header is the DDP header, skb->len
1408  *      is the DDP header, skb->len is the DDP length. The physical headers
1409  *      have been extracted. PPP should probably pass frames marked as for this
1410  *      layer.  [ie ARPHRD_ETHERTALK]
1411  */
1412 static int atalk_rcv(struct sk_buff *skb, struct net_device *dev,
1413                      struct packet_type *pt, struct net_device *orig_dev)
1414 {
1415         struct ddpehdr *ddp;
1416         struct sock *sock;
1417         struct atalk_iface *atif;
1418         struct sockaddr_at tosat;
1419         int origlen;
1420         __u16 len_hops;
1421 
1422         if (!net_eq(dev_net(dev), &init_net))
1423                 goto drop;
1424 
1425         /* Don't mangle buffer if shared */
1426         if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
1427                 goto out;
1428 
1429         /* Size check and make sure header is contiguous */
1430         if (!pskb_may_pull(skb, sizeof(*ddp)))
1431                 goto drop;
1432 
1433         ddp = ddp_hdr(skb);
1434 
1435         len_hops = ntohs(ddp->deh_len_hops);
1436 
1437         /* Trim buffer in case of stray trailing data */
1438         origlen = skb->len;
1439         skb_trim(skb, min_t(unsigned int, skb->len, len_hops & 1023));
1440 
1441         /*
1442          * Size check to see if ddp->deh_len was crap
1443          * (Otherwise we'll detonate most spectacularly
1444          * in the middle of atalk_checksum() or recvmsg()).
1445          */
1446         if (skb->len < sizeof(*ddp) || skb->len < (len_hops & 1023)) {
1447                 pr_debug("AppleTalk: dropping corrupted frame (deh_len=%u, "
1448                          "skb->len=%u)\n", len_hops & 1023, skb->len);
1449                 goto drop;
1450         }
1451 
1452         /*
1453          * Any checksums. Note we don't do htons() on this == is assumed to be
1454          * valid for net byte orders all over the networking code...
1455          */
1456         if (ddp->deh_sum &&
1457             atalk_checksum(skb, len_hops & 1023) != ddp->deh_sum)
1458                 /* Not a valid AppleTalk frame - dustbin time */
1459                 goto drop;
1460 
1461         /* Check the packet is aimed at us */
1462         if (!ddp->deh_dnet)     /* Net 0 is 'this network' */
1463                 atif = atalk_find_anynet(ddp->deh_dnode, dev);
1464         else
1465                 atif = atalk_find_interface(ddp->deh_dnet, ddp->deh_dnode);
1466 
1467         if (!atif) {
1468                 /* Not ours, so we route the packet via the correct
1469                  * AppleTalk iface
1470                  */
1471                 return atalk_route_packet(skb, dev, ddp, len_hops, origlen);
1472         }
1473 
1474         /* if IP over DDP is not selected this code will be optimized out */
1475         if (is_ip_over_ddp(skb))
1476                 return handle_ip_over_ddp(skb);
1477         /*
1478          * Which socket - atalk_search_socket() looks for a *full match*
1479          * of the <net, node, port> tuple.
1480          */
1481         tosat.sat_addr.s_net  = ddp->deh_dnet;
1482         tosat.sat_addr.s_node = ddp->deh_dnode;
1483         tosat.sat_port        = ddp->deh_dport;
1484 
1485         sock = atalk_search_socket(&tosat, atif);
1486         if (!sock) /* But not one of our sockets */
1487                 goto drop;
1488 
1489         /* Queue packet (standard) */
1490         if (sock_queue_rcv_skb(sock, skb) < 0)
1491                 goto drop;
1492 
1493         return NET_RX_SUCCESS;
1494 
1495 drop:
1496         kfree_skb(skb);
1497 out:
1498         return NET_RX_DROP;
1499 
1500 }
1501 
1502 /*
1503  * Receive a LocalTalk frame. We make some demands on the caller here.
1504  * Caller must provide enough headroom on the packet to pull the short
1505  * header and append a long one.
1506  */
1507 static int ltalk_rcv(struct sk_buff *skb, struct net_device *dev,
1508                      struct packet_type *pt, struct net_device *orig_dev)
1509 {
1510         if (!net_eq(dev_net(dev), &init_net))
1511                 goto freeit;
1512 
1513         /* Expand any short form frames */
1514         if (skb_mac_header(skb)[2] == 1) {
1515                 struct ddpehdr *ddp;
1516                 /* Find our address */
1517                 struct atalk_addr *ap = atalk_find_dev_addr(dev);
1518 
1519                 if (!ap || skb->len < sizeof(__be16) || skb->len > 1023)
1520                         goto freeit;
1521 
1522                 /* Don't mangle buffer if shared */
1523                 if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
1524                         return 0;
1525 
1526                 /*
1527                  * The push leaves us with a ddephdr not an shdr, and
1528                  * handily the port bytes in the right place preset.
1529                  */
1530                 ddp = skb_push(skb, sizeof(*ddp) - 4);
1531 
1532                 /* Now fill in the long header */
1533 
1534                 /*
1535                  * These two first. The mac overlays the new source/dest
1536                  * network information so we MUST copy these before
1537                  * we write the network numbers !
1538                  */
1539 
1540                 ddp->deh_dnode = skb_mac_header(skb)[0];     /* From physical header */
1541                 ddp->deh_snode = skb_mac_header(skb)[1];     /* From physical header */
1542 
1543                 ddp->deh_dnet  = ap->s_net;     /* Network number */
1544                 ddp->deh_snet  = ap->s_net;
1545                 ddp->deh_sum   = 0;             /* No checksum */
1546                 /*
1547                  * Not sure about this bit...
1548                  */
1549                 /* Non routable, so force a drop if we slip up later */
1550                 ddp->deh_len_hops = htons(skb->len + (DDP_MAXHOPS << 10));
1551         }
1552         skb_reset_transport_header(skb);
1553 
1554         return atalk_rcv(skb, dev, pt, orig_dev);
1555 freeit:
1556         kfree_skb(skb);
1557         return 0;
1558 }
1559 
1560 static int atalk_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1561 {
1562         struct sock *sk = sock->sk;
1563         struct atalk_sock *at = at_sk(sk);
1564         DECLARE_SOCKADDR(struct sockaddr_at *, usat, msg->msg_name);
1565         int flags = msg->msg_flags;
1566         int loopback = 0;
1567         struct sockaddr_at local_satalk, gsat;
1568         struct sk_buff *skb;
1569         struct net_device *dev;
1570         struct ddpehdr *ddp;
1571         int size;
1572         struct atalk_route *rt;
1573         int err;
1574 
1575         if (flags & ~(MSG_DONTWAIT|MSG_CMSG_COMPAT))
1576                 return -EINVAL;
1577 
1578         if (len > DDP_MAXSZ)
1579                 return -EMSGSIZE;
1580 
1581         lock_sock(sk);
1582         if (usat) {
1583                 err = -EBUSY;
1584                 if (sock_flag(sk, SOCK_ZAPPED))
1585                         if (atalk_autobind(sk) < 0)
1586                                 goto out;
1587 
1588                 err = -EINVAL;
1589                 if (msg->msg_namelen < sizeof(*usat) ||
1590                     usat->sat_family != AF_APPLETALK)
1591                         goto out;
1592 
1593                 err = -EPERM;
1594                 /* netatalk didn't implement this check */
1595                 if (usat->sat_addr.s_node == ATADDR_BCAST &&
1596                     !sock_flag(sk, SOCK_BROADCAST)) {
1597                         goto out;
1598                 }
1599         } else {
1600                 err = -ENOTCONN;
1601                 if (sk->sk_state != TCP_ESTABLISHED)
1602                         goto out;
1603                 usat = &local_satalk;
1604                 usat->sat_family      = AF_APPLETALK;
1605                 usat->sat_port        = at->dest_port;
1606                 usat->sat_addr.s_node = at->dest_node;
1607                 usat->sat_addr.s_net  = at->dest_net;
1608         }
1609 
1610         /* Build a packet */
1611         SOCK_DEBUG(sk, "SK %p: Got address.\n", sk);
1612 
1613         /* For headers */
1614         size = sizeof(struct ddpehdr) + len + ddp_dl->header_length;
1615 
1616         if (usat->sat_addr.s_net || usat->sat_addr.s_node == ATADDR_ANYNODE) {
1617                 rt = atrtr_find(&usat->sat_addr);
1618         } else {
1619                 struct atalk_addr at_hint;
1620 
1621                 at_hint.s_node = 0;
1622                 at_hint.s_net  = at->src_net;
1623 
1624                 rt = atrtr_find(&at_hint);
1625         }
1626         err = -ENETUNREACH;
1627         if (!rt)
1628                 goto out;
1629 
1630         dev = rt->dev;
1631 
1632         SOCK_DEBUG(sk, "SK %p: Size needed %d, device %s\n",
1633                         sk, size, dev->name);
1634 
1635         size += dev->hard_header_len;
1636         release_sock(sk);
1637         skb = sock_alloc_send_skb(sk, size, (flags & MSG_DONTWAIT), &err);
1638         lock_sock(sk);
1639         if (!skb)
1640                 goto out;
1641 
1642         skb_reserve(skb, ddp_dl->header_length);
1643         skb_reserve(skb, dev->hard_header_len);
1644         skb->dev = dev;
1645 
1646         SOCK_DEBUG(sk, "SK %p: Begin build.\n", sk);
1647 
1648         ddp = skb_put(skb, sizeof(struct ddpehdr));
1649         ddp->deh_len_hops  = htons(len + sizeof(*ddp));
1650         ddp->deh_dnet  = usat->sat_addr.s_net;
1651         ddp->deh_snet  = at->src_net;
1652         ddp->deh_dnode = usat->sat_addr.s_node;
1653         ddp->deh_snode = at->src_node;
1654         ddp->deh_dport = usat->sat_port;
1655         ddp->deh_sport = at->src_port;
1656 
1657         SOCK_DEBUG(sk, "SK %p: Copy user data (%zd bytes).\n", sk, len);
1658 
1659         err = memcpy_from_msg(skb_put(skb, len), msg, len);
1660         if (err) {
1661                 kfree_skb(skb);
1662                 err = -EFAULT;
1663                 goto out;
1664         }
1665 
1666         if (sk->sk_no_check_tx)
1667                 ddp->deh_sum = 0;
1668         else
1669                 ddp->deh_sum = atalk_checksum(skb, len + sizeof(*ddp));
1670 
1671         /*
1672          * Loopback broadcast packets to non gateway targets (ie routes
1673          * to group we are in)
1674          */
1675         if (ddp->deh_dnode == ATADDR_BCAST &&
1676             !(rt->flags & RTF_GATEWAY) && !(dev->flags & IFF_LOOPBACK)) {
1677                 struct sk_buff *skb2 = skb_copy(skb, GFP_KERNEL);
1678 
1679                 if (skb2) {
1680                         loopback = 1;
1681                         SOCK_DEBUG(sk, "SK %p: send out(copy).\n", sk);
1682                         /*
1683                          * If it fails it is queued/sent above in the aarp queue
1684                          */
1685                         aarp_send_ddp(dev, skb2, &usat->sat_addr, NULL);
1686                 }
1687         }
1688 
1689         if (dev->flags & IFF_LOOPBACK || loopback) {
1690                 SOCK_DEBUG(sk, "SK %p: Loop back.\n", sk);
1691                 /* loop back */
1692                 skb_orphan(skb);
1693                 if (ddp->deh_dnode == ATADDR_BCAST) {
1694                         struct atalk_addr at_lo;
1695 
1696                         at_lo.s_node = 0;
1697                         at_lo.s_net  = 0;
1698 
1699                         rt = atrtr_find(&at_lo);
1700                         if (!rt) {
1701                                 kfree_skb(skb);
1702                                 err = -ENETUNREACH;
1703                                 goto out;
1704                         }
1705                         dev = rt->dev;
1706                         skb->dev = dev;
1707                 }
1708                 ddp_dl->request(ddp_dl, skb, dev->dev_addr);
1709         } else {
1710                 SOCK_DEBUG(sk, "SK %p: send out.\n", sk);
1711                 if (rt->flags & RTF_GATEWAY) {
1712                     gsat.sat_addr = rt->gateway;
1713                     usat = &gsat;
1714                 }
1715 
1716                 /*
1717                  * If it fails it is queued/sent above in the aarp queue
1718                  */
1719                 aarp_send_ddp(dev, skb, &usat->sat_addr, NULL);
1720         }
1721         SOCK_DEBUG(sk, "SK %p: Done write (%zd).\n", sk, len);
1722 
1723 out:
1724         release_sock(sk);
1725         return err ? : len;
1726 }
1727 
1728 static int atalk_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1729                          int flags)
1730 {
1731         struct sock *sk = sock->sk;
1732         struct ddpehdr *ddp;
1733         int copied = 0;
1734         int offset = 0;
1735         int err = 0;
1736         struct sk_buff *skb;
1737 
1738         skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1739                                                 flags & MSG_DONTWAIT, &err);
1740         lock_sock(sk);
1741 
1742         if (!skb)
1743                 goto out;
1744 
1745         /* FIXME: use skb->cb to be able to use shared skbs */
1746         ddp = ddp_hdr(skb);
1747         copied = ntohs(ddp->deh_len_hops) & 1023;
1748 
1749         if (sk->sk_type != SOCK_RAW) {
1750                 offset = sizeof(*ddp);
1751                 copied -= offset;
1752         }
1753 
1754         if (copied > size) {
1755                 copied = size;
1756                 msg->msg_flags |= MSG_TRUNC;
1757         }
1758         err = skb_copy_datagram_msg(skb, offset, msg, copied);
1759 
1760         if (!err && msg->msg_name) {
1761                 DECLARE_SOCKADDR(struct sockaddr_at *, sat, msg->msg_name);
1762                 sat->sat_family      = AF_APPLETALK;
1763                 sat->sat_port        = ddp->deh_sport;
1764                 sat->sat_addr.s_node = ddp->deh_snode;
1765                 sat->sat_addr.s_net  = ddp->deh_snet;
1766                 msg->msg_namelen     = sizeof(*sat);
1767         }
1768 
1769         skb_free_datagram(sk, skb);     /* Free the datagram. */
1770 
1771 out:
1772         release_sock(sk);
1773         return err ? : copied;
1774 }
1775 
1776 
1777 /*
1778  * AppleTalk ioctl calls.
1779  */
1780 static int atalk_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1781 {
1782         int rc = -ENOIOCTLCMD;
1783         struct sock *sk = sock->sk;
1784         void __user *argp = (void __user *)arg;
1785 
1786         switch (cmd) {
1787         /* Protocol layer */
1788         case TIOCOUTQ: {
1789                 long amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1790 
1791                 if (amount < 0)
1792                         amount = 0;
1793                 rc = put_user(amount, (int __user *)argp);
1794                 break;
1795         }
1796         case TIOCINQ: {
1797                 /*
1798                  * These two are safe on a single CPU system as only
1799                  * user tasks fiddle here
1800                  */
1801                 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
1802                 long amount = 0;
1803 
1804                 if (skb)
1805                         amount = skb->len - sizeof(struct ddpehdr);
1806                 rc = put_user(amount, (int __user *)argp);
1807                 break;
1808         }
1809         /* Routing */
1810         case SIOCADDRT:
1811         case SIOCDELRT:
1812                 rc = -EPERM;
1813                 if (capable(CAP_NET_ADMIN))
1814                         rc = atrtr_ioctl(cmd, argp);
1815                 break;
1816         /* Interface */
1817         case SIOCGIFADDR:
1818         case SIOCSIFADDR:
1819         case SIOCGIFBRDADDR:
1820         case SIOCATALKDIFADDR:
1821         case SIOCDIFADDR:
1822         case SIOCSARP:          /* proxy AARP */
1823         case SIOCDARP:          /* proxy AARP */
1824                 rtnl_lock();
1825                 rc = atif_ioctl(cmd, argp);
1826                 rtnl_unlock();
1827                 break;
1828         }
1829 
1830         return rc;
1831 }
1832 
1833 
1834 #ifdef CONFIG_COMPAT
1835 static int atalk_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1836 {
1837         /*
1838          * SIOCATALKDIFADDR is a SIOCPROTOPRIVATE ioctl number, so we
1839          * cannot handle it in common code. The data we access if ifreq
1840          * here is compatible, so we can simply call the native
1841          * handler.
1842          */
1843         if (cmd == SIOCATALKDIFADDR)
1844                 return atalk_ioctl(sock, cmd, (unsigned long)compat_ptr(arg));
1845 
1846         return -ENOIOCTLCMD;
1847 }
1848 #endif
1849 
1850 
1851 static const struct net_proto_family atalk_family_ops = {
1852         .family         = PF_APPLETALK,
1853         .create         = atalk_create,
1854         .owner          = THIS_MODULE,
1855 };
1856 
1857 static const struct proto_ops atalk_dgram_ops = {
1858         .family         = PF_APPLETALK,
1859         .owner          = THIS_MODULE,
1860         .release        = atalk_release,
1861         .bind           = atalk_bind,
1862         .connect        = atalk_connect,
1863         .socketpair     = sock_no_socketpair,
1864         .accept         = sock_no_accept,
1865         .getname        = atalk_getname,
1866         .poll           = datagram_poll,
1867         .ioctl          = atalk_ioctl,
1868         .gettstamp      = sock_gettstamp,
1869 #ifdef CONFIG_COMPAT
1870         .compat_ioctl   = atalk_compat_ioctl,
1871 #endif
1872         .listen         = sock_no_listen,
1873         .shutdown       = sock_no_shutdown,
1874         .setsockopt     = sock_no_setsockopt,
1875         .getsockopt     = sock_no_getsockopt,
1876         .sendmsg        = atalk_sendmsg,
1877         .recvmsg        = atalk_recvmsg,
1878         .mmap           = sock_no_mmap,
1879         .sendpage       = sock_no_sendpage,
1880 };
1881 
1882 static struct notifier_block ddp_notifier = {
1883         .notifier_call  = ddp_device_event,
1884 };
1885 
1886 static struct packet_type ltalk_packet_type __read_mostly = {
1887         .type           = cpu_to_be16(ETH_P_LOCALTALK),
1888         .func           = ltalk_rcv,
1889 };
1890 
1891 static struct packet_type ppptalk_packet_type __read_mostly = {
1892         .type           = cpu_to_be16(ETH_P_PPPTALK),
1893         .func           = atalk_rcv,
1894 };
1895 
1896 static unsigned char ddp_snap_id[] = { 0x08, 0x00, 0x07, 0x80, 0x9B };
1897 
1898 /* Export symbols for use by drivers when AppleTalk is a module */
1899 EXPORT_SYMBOL(atrtr_get_dev);
1900 EXPORT_SYMBOL(atalk_find_dev_addr);
1901 
1902 /* Called by proto.c on kernel start up */
1903 static int __init atalk_init(void)
1904 {
1905         int rc;
1906 
1907         rc = proto_register(&ddp_proto, 0);
1908         if (rc)
1909                 goto out;
1910 
1911         rc = sock_register(&atalk_family_ops);
1912         if (rc)
1913                 goto out_proto;
1914 
1915         ddp_dl = register_snap_client(ddp_snap_id, atalk_rcv);
1916         if (!ddp_dl) {
1917                 pr_crit("Unable to register DDP with SNAP.\n");
1918                 rc = -ENOMEM;
1919                 goto out_sock;
1920         }
1921 
1922         dev_add_pack(&ltalk_packet_type);
1923         dev_add_pack(&ppptalk_packet_type);
1924 
1925         rc = register_netdevice_notifier(&ddp_notifier);
1926         if (rc)
1927                 goto out_snap;
1928 
1929         rc = aarp_proto_init();
1930         if (rc)
1931                 goto out_dev;
1932 
1933         rc = atalk_proc_init();
1934         if (rc)
1935                 goto out_aarp;
1936 
1937         rc = atalk_register_sysctl();
1938         if (rc)
1939                 goto out_proc;
1940 out:
1941         return rc;
1942 out_proc:
1943         atalk_proc_exit();
1944 out_aarp:
1945         aarp_cleanup_module();
1946 out_dev:
1947         unregister_netdevice_notifier(&ddp_notifier);
1948 out_snap:
1949         dev_remove_pack(&ppptalk_packet_type);
1950         dev_remove_pack(&ltalk_packet_type);
1951         unregister_snap_client(ddp_dl);
1952 out_sock:
1953         sock_unregister(PF_APPLETALK);
1954 out_proto:
1955         proto_unregister(&ddp_proto);
1956         goto out;
1957 }
1958 module_init(atalk_init);
1959 
1960 /*
1961  * No explicit module reference count manipulation is needed in the
1962  * protocol. Socket layer sets module reference count for us
1963  * and interfaces reference counting is done
1964  * by the network device layer.
1965  *
1966  * Ergo, before the AppleTalk module can be removed, all AppleTalk
1967  * sockets be closed from user space.
1968  */
1969 static void __exit atalk_exit(void)
1970 {
1971 #ifdef CONFIG_SYSCTL
1972         atalk_unregister_sysctl();
1973 #endif /* CONFIG_SYSCTL */
1974         atalk_proc_exit();
1975         aarp_cleanup_module();  /* General aarp clean-up. */
1976         unregister_netdevice_notifier(&ddp_notifier);
1977         dev_remove_pack(&ltalk_packet_type);
1978         dev_remove_pack(&ppptalk_packet_type);
1979         unregister_snap_client(ddp_dl);
1980         sock_unregister(PF_APPLETALK);
1981         proto_unregister(&ddp_proto);
1982 }
1983 module_exit(atalk_exit);
1984 
1985 MODULE_LICENSE("GPL");
1986 MODULE_AUTHOR("Alan Cox <alan@lxorguk.ukuu.org.uk>");
1987 MODULE_DESCRIPTION("AppleTalk 0.20\n");
1988 MODULE_ALIAS_NETPROTO(PF_APPLETALK);
/* [<][>][^][v][top][bottom][index][help] */
root/net/appletalk/ddp.c

DEFINITIONS
