1 /* 2 * DDP: An implementation of the AppleTalk DDP protocol for 3 * Ethernet 'ELAP'. 4 * 5 * Alan Cox <alan@lxorguk.ukuu.org.uk> 6 * 7 * With more than a little assistance from 8 * 9 * Wesley Craig <netatalk@umich.edu> 10 * 11 * Fixes: 12 * Neil Horman : Added missing device ioctls 13 * Michael Callahan : Made routing work 14 * Wesley Craig : Fix probing to listen to a 15 * passed node id. 16 * Alan Cox : Added send/recvmsg support 17 * Alan Cox : Moved at. to protinfo in 18 * socket. 19 * Alan Cox : Added firewall hooks. 20 * Alan Cox : Supports new ARPHRD_LOOPBACK 21 * Christer Weinigel : Routing and /proc fixes. 22 * Bradford Johnson : LocalTalk. 23 * Tom Dyas : Module support. 24 * Alan Cox : Hooks for PPP (based on the 25 * LocalTalk hook). 26 * Alan Cox : Posix bits 27 * Alan Cox/Mike Freeman : Possible fix to NBP problems 28 * Bradford Johnson : IP-over-DDP (experimental) 29 * Jay Schulist : Moved IP-over-DDP to its own 30 * driver file. (ipddp.c & ipddp.h) 31 * Jay Schulist : Made work as module with 32 * AppleTalk drivers, cleaned it. 33 * Rob Newberry : Added proxy AARP and AARP 34 * procfs, moved probing to AARP 35 * module. 36 * Adrian Sun/ 37 * Michael Zuelsdorff : fix for net.0 packets. don't 38 * allow illegal ether/tokentalk 39 * port assignment. we lose a 40 * valid localtalk port as a 41 * result. 42 * Arnaldo C. de Melo : Cleanup, in preparation for 43 * shared skb support 8) 44 * Arnaldo C. de Melo : Move proc stuff to atalk_proc.c, 45 * use seq_file 46 * 47 * This program is free software; you can redistribute it and/or 48 * modify it under the terms of the GNU General Public License 49 * as published by the Free Software Foundation; either version 50 * 2 of the License, or (at your option) any later version. 51 * 52 */ 53 54 #include <linux/capability.h> 55 #include <linux/module.h> 56 #include <linux/if_arp.h> 57 #include <linux/smp_lock.h> 58 #include <linux/termios.h> /* For TIOCOUTQ/INQ */ 59 #include <linux/compat.h> 60 #include <net/datalink.h> 61 #include <net/psnap.h> 62 #include <net/sock.h> 63 #include <net/tcp_states.h> 64 #include <net/route.h> 65 #include <linux/atalk.h> 66 #include "../core/kmap_skb.h" 67 68 struct datalink_proto *ddp_dl, *aarp_dl; 69 static const struct proto_ops atalk_dgram_ops; 70 71 /**************************************************************************\ 72 * * 73 * Handlers for the socket list. * 74 * * 75 \**************************************************************************/ 76 77 HLIST_HEAD(atalk_sockets); 78 DEFINE_RWLOCK(atalk_sockets_lock); 79 80 static inline void __atalk_insert_socket(struct sock *sk) 81 { 82 sk_add_node(sk, &atalk_sockets); 83 } 84 85 static inline void atalk_remove_socket(struct sock *sk) 86 { 87 write_lock_bh(&atalk_sockets_lock); 88 sk_del_node_init(sk); 89 write_unlock_bh(&atalk_sockets_lock); 90 } 91 92 static struct sock *atalk_search_socket(struct sockaddr_at *to, 93 struct atalk_iface *atif) 94 { 95 struct sock *s; 96 struct hlist_node *node; 97 98 read_lock_bh(&atalk_sockets_lock); 99 sk_for_each(s, node, &atalk_sockets) { 100 struct atalk_sock *at = at_sk(s); 101 102 if (to->sat_port != at->src_port) 103 continue; 104 105 if (to->sat_addr.s_net == ATADDR_ANYNET && 106 to->sat_addr.s_node == ATADDR_BCAST) 107 goto found; 108 109 if (to->sat_addr.s_net == at->src_net && 110 (to->sat_addr.s_node == at->src_node || 111 to->sat_addr.s_node == ATADDR_BCAST || 112 to->sat_addr.s_node == ATADDR_ANYNODE)) 113 goto found; 114 115 /* XXXX.0 -- we got a request for this router. make sure 116 * that the node is appropriately set. */ 117 if (to->sat_addr.s_node == ATADDR_ANYNODE && 118 to->sat_addr.s_net != ATADDR_ANYNET && 119 atif->address.s_node == at->src_node) { 120 to->sat_addr.s_node = atif->address.s_node; 121 goto found; 122 } 123 } 124 s = NULL; 125 found: 126 read_unlock_bh(&atalk_sockets_lock); 127 return s; 128 } 129 130 /** 131 * atalk_find_or_insert_socket - Try to find a socket matching ADDR 132 * @sk - socket to insert in the list if it is not there already 133 * @sat - address to search for 134 * 135 * Try to find a socket matching ADDR in the socket list, if found then return 136 * it. If not, insert SK into the socket list. 137 * 138 * This entire operation must execute atomically. 139 */ 140 static struct sock *atalk_find_or_insert_socket(struct sock *sk, 141 struct sockaddr_at *sat) 142 { 143 struct sock *s; 144 struct hlist_node *node; 145 struct atalk_sock *at; 146 147 write_lock_bh(&atalk_sockets_lock); 148 sk_for_each(s, node, &atalk_sockets) { 149 at = at_sk(s); 150 151 if (at->src_net == sat->sat_addr.s_net && 152 at->src_node == sat->sat_addr.s_node && 153 at->src_port == sat->sat_port) 154 goto found; 155 } 156 s = NULL; 157 __atalk_insert_socket(sk); /* Wheee, it's free, assign and insert. */ 158 found: 159 write_unlock_bh(&atalk_sockets_lock); 160 return s; 161 } 162 163 static void atalk_destroy_timer(unsigned long data) 164 { 165 struct sock *sk = (struct sock *)data; 166 167 if (sk_has_allocations(sk)) { 168 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME; 169 add_timer(&sk->sk_timer); 170 } else 171 sock_put(sk); 172 } 173 174 static inline void atalk_destroy_socket(struct sock *sk) 175 { 176 atalk_remove_socket(sk); 177 skb_queue_purge(&sk->sk_receive_queue); 178 179 if (sk_has_allocations(sk)) { 180 setup_timer(&sk->sk_timer, atalk_destroy_timer, 181 (unsigned long)sk); 182 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME; 183 add_timer(&sk->sk_timer); 184 } else 185 sock_put(sk); 186 } 187 188 /**************************************************************************\ 189 * * 190 * Routing tables for the AppleTalk socket layer. * 191 * * 192 \**************************************************************************/ 193 194 /* Anti-deadlock ordering is atalk_routes_lock --> iface_lock -DaveM */ 195 struct atalk_route *atalk_routes; 196 DEFINE_RWLOCK(atalk_routes_lock); 197 198 struct atalk_iface *atalk_interfaces; 199 DEFINE_RWLOCK(atalk_interfaces_lock); 200 201 /* For probing devices or in a routerless network */ 202 struct atalk_route atrtr_default; 203 204 /* AppleTalk interface control */ 205 /* 206 * Drop a device. Doesn't drop any of its routes - that is the caller's 207 * problem. Called when we down the interface or delete the address. 208 */ 209 static void atif_drop_device(struct net_device *dev) 210 { 211 struct atalk_iface **iface = &atalk_interfaces; 212 struct atalk_iface *tmp; 213 214 write_lock_bh(&atalk_interfaces_lock); 215 while ((tmp = *iface) != NULL) { 216 if (tmp->dev == dev) { 217 *iface = tmp->next; 218 dev_put(dev); 219 kfree(tmp); 220 dev->atalk_ptr = NULL; 221 } else 222 iface = &tmp->next; 223 } 224 write_unlock_bh(&atalk_interfaces_lock); 225 } 226 227 static struct atalk_iface *atif_add_device(struct net_device *dev, 228 struct atalk_addr *sa) 229 { 230 struct atalk_iface *iface = kzalloc(sizeof(*iface), GFP_KERNEL); 231 232 if (!iface) 233 goto out; 234 235 dev_hold(dev); 236 iface->dev = dev; 237 dev->atalk_ptr = iface; 238 iface->address = *sa; 239 iface->status = 0; 240 241 write_lock_bh(&atalk_interfaces_lock); 242 iface->next = atalk_interfaces; 243 atalk_interfaces = iface; 244 write_unlock_bh(&atalk_interfaces_lock); 245 out: 246 return iface; 247 } 248 249 /* Perform phase 2 AARP probing on our tentative address */ 250 static int atif_probe_device(struct atalk_iface *atif) 251 { 252 int netrange = ntohs(atif->nets.nr_lastnet) - 253 ntohs(atif->nets.nr_firstnet) + 1; 254 int probe_net = ntohs(atif->address.s_net); 255 int probe_node = atif->address.s_node; 256 int netct, nodect; 257 258 /* Offset the network we start probing with */ 259 if (probe_net == ATADDR_ANYNET) { 260 probe_net = ntohs(atif->nets.nr_firstnet); 261 if (netrange) 262 probe_net += jiffies % netrange; 263 } 264 if (probe_node == ATADDR_ANYNODE) 265 probe_node = jiffies & 0xFF; 266 267 /* Scan the networks */ 268 atif->status |= ATIF_PROBE; 269 for (netct = 0; netct <= netrange; netct++) { 270 /* Sweep the available nodes from a given start */ 271 atif->address.s_net = htons(probe_net); 272 for (nodect = 0; nodect < 256; nodect++) { 273 atif->address.s_node = (nodect + probe_node) & 0xFF; 274 if (atif->address.s_node > 0 && 275 atif->address.s_node < 254) { 276 /* Probe a proposed address */ 277 aarp_probe_network(atif); 278 279 if (!(atif->status & ATIF_PROBE_FAIL)) { 280 atif->status &= ~ATIF_PROBE; 281 return 0; 282 } 283 } 284 atif->status &= ~ATIF_PROBE_FAIL; 285 } 286 probe_net++; 287 if (probe_net > ntohs(atif->nets.nr_lastnet)) 288 probe_net = ntohs(atif->nets.nr_firstnet); 289 } 290 atif->status &= ~ATIF_PROBE; 291 292 return -EADDRINUSE; /* Network is full... */ 293 } 294 295 296 /* Perform AARP probing for a proxy address */ 297 static int atif_proxy_probe_device(struct atalk_iface *atif, 298 struct atalk_addr* proxy_addr) 299 { 300 int netrange = ntohs(atif->nets.nr_lastnet) - 301 ntohs(atif->nets.nr_firstnet) + 1; 302 /* we probe the interface's network */ 303 int probe_net = ntohs(atif->address.s_net); 304 int probe_node = ATADDR_ANYNODE; /* we'll take anything */ 305 int netct, nodect; 306 307 /* Offset the network we start probing with */ 308 if (probe_net == ATADDR_ANYNET) { 309 probe_net = ntohs(atif->nets.nr_firstnet); 310 if (netrange) 311 probe_net += jiffies % netrange; 312 } 313 314 if (probe_node == ATADDR_ANYNODE) 315 probe_node = jiffies & 0xFF; 316 317 /* Scan the networks */ 318 for (netct = 0; netct <= netrange; netct++) { 319 /* Sweep the available nodes from a given start */ 320 proxy_addr->s_net = htons(probe_net); 321 for (nodect = 0; nodect < 256; nodect++) { 322 proxy_addr->s_node = (nodect + probe_node) & 0xFF; 323 if (proxy_addr->s_node > 0 && 324 proxy_addr->s_node < 254) { 325 /* Tell AARP to probe a proposed address */ 326 int ret = aarp_proxy_probe_network(atif, 327 proxy_addr); 328 329 if (ret != -EADDRINUSE) 330 return ret; 331 } 332 } 333 probe_net++; 334 if (probe_net > ntohs(atif->nets.nr_lastnet)) 335 probe_net = ntohs(atif->nets.nr_firstnet); 336 } 337 338 return -EADDRINUSE; /* Network is full... */ 339 } 340 341 342 struct atalk_addr *atalk_find_dev_addr(struct net_device *dev) 343 { 344 struct atalk_iface *iface = dev->atalk_ptr; 345 return iface ? &iface->address : NULL; 346 } 347 348 static struct atalk_addr *atalk_find_primary(void) 349 { 350 struct atalk_iface *fiface = NULL; 351 struct atalk_addr *retval; 352 struct atalk_iface *iface; 353 354 /* 355 * Return a point-to-point interface only if 356 * there is no non-ptp interface available. 357 */ 358 read_lock_bh(&atalk_interfaces_lock); 359 for (iface = atalk_interfaces; iface; iface = iface->next) { 360 if (!fiface && !(iface->dev->flags & IFF_LOOPBACK)) 361 fiface = iface; 362 if (!(iface->dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) { 363 retval = &iface->address; 364 goto out; 365 } 366 } 367 368 if (fiface) 369 retval = &fiface->address; 370 else if (atalk_interfaces) 371 retval = &atalk_interfaces->address; 372 else 373 retval = NULL; 374 out: 375 read_unlock_bh(&atalk_interfaces_lock); 376 return retval; 377 } 378 379 /* 380 * Find a match for 'any network' - ie any of our interfaces with that 381 * node number will do just nicely. 382 */ 383 static struct atalk_iface *atalk_find_anynet(int node, struct net_device *dev) 384 { 385 struct atalk_iface *iface = dev->atalk_ptr; 386 387 if (!iface || iface->status & ATIF_PROBE) 388 goto out_err; 389 390 if (node != ATADDR_BCAST && 391 iface->address.s_node != node && 392 node != ATADDR_ANYNODE) 393 goto out_err; 394 out: 395 return iface; 396 out_err: 397 iface = NULL; 398 goto out; 399 } 400 401 /* Find a match for a specific network:node pair */ 402 static struct atalk_iface *atalk_find_interface(__be16 net, int node) 403 { 404 struct atalk_iface *iface; 405 406 read_lock_bh(&atalk_interfaces_lock); 407 for (iface = atalk_interfaces; iface; iface = iface->next) { 408 if ((node == ATADDR_BCAST || 409 node == ATADDR_ANYNODE || 410 iface->address.s_node == node) && 411 iface->address.s_net == net && 412 !(iface->status & ATIF_PROBE)) 413 break; 414 415 /* XXXX.0 -- net.0 returns the iface associated with net */ 416 if (node == ATADDR_ANYNODE && net != ATADDR_ANYNET && 417 ntohs(iface->nets.nr_firstnet) <= ntohs(net) && 418 ntohs(net) <= ntohs(iface->nets.nr_lastnet)) 419 break; 420 } 421 read_unlock_bh(&atalk_interfaces_lock); 422 return iface; 423 } 424 425 426 /* 427 * Find a route for an AppleTalk packet. This ought to get cached in 428 * the socket (later on...). We know about host routes and the fact 429 * that a route must be direct to broadcast. 430 */ 431 static struct atalk_route *atrtr_find(struct atalk_addr *target) 432 { 433 /* 434 * we must search through all routes unless we find a 435 * host route, because some host routes might overlap 436 * network routes 437 */ 438 struct atalk_route *net_route = NULL; 439 struct atalk_route *r; 440 441 read_lock_bh(&atalk_routes_lock); 442 for (r = atalk_routes; r; r = r->next) { 443 if (!(r->flags & RTF_UP)) 444 continue; 445 446 if (r->target.s_net == target->s_net) { 447 if (r->flags & RTF_HOST) { 448 /* 449 * if this host route is for the target, 450 * the we're done 451 */ 452 if (r->target.s_node == target->s_node) 453 goto out; 454 } else 455 /* 456 * this route will work if there isn't a 457 * direct host route, so cache it 458 */ 459 net_route = r; 460 } 461 } 462 463 /* 464 * if we found a network route but not a direct host 465 * route, then return it 466 */ 467 if (net_route) 468 r = net_route; 469 else if (atrtr_default.dev) 470 r = &atrtr_default; 471 else /* No route can be found */ 472 r = NULL; 473 out: 474 read_unlock_bh(&atalk_routes_lock); 475 return r; 476 } 477 478 479 /* 480 * Given an AppleTalk network, find the device to use. This can be 481 * a simple lookup. 482 */ 483 struct net_device *atrtr_get_dev(struct atalk_addr *sa) 484 { 485 struct atalk_route *atr = atrtr_find(sa); 486 return atr ? atr->dev : NULL; 487 } 488 489 /* Set up a default router */ 490 static void atrtr_set_default(struct net_device *dev) 491 { 492 atrtr_default.dev = dev; 493 atrtr_default.flags = RTF_UP; 494 atrtr_default.gateway.s_net = htons(0); 495 atrtr_default.gateway.s_node = 0; 496 } 497 498 /* 499 * Add a router. Basically make sure it looks valid and stuff the 500 * entry in the list. While it uses netranges we always set them to one 501 * entry to work like netatalk. 502 */ 503 static int atrtr_create(struct rtentry *r, struct net_device *devhint) 504 { 505 struct sockaddr_at *ta = (struct sockaddr_at *)&r->rt_dst; 506 struct sockaddr_at *ga = (struct sockaddr_at *)&r->rt_gateway; 507 struct atalk_route *rt; 508 struct atalk_iface *iface, *riface; 509 int retval = -EINVAL; 510 511 /* 512 * Fixme: Raise/Lower a routing change semaphore for these 513 * operations. 514 */ 515 516 /* Validate the request */ 517 if (ta->sat_family != AF_APPLETALK || 518 (!devhint && ga->sat_family != AF_APPLETALK)) 519 goto out; 520 521 /* Now walk the routing table and make our decisions */ 522 write_lock_bh(&atalk_routes_lock); 523 for (rt = atalk_routes; rt; rt = rt->next) { 524 if (r->rt_flags != rt->flags) 525 continue; 526 527 if (ta->sat_addr.s_net == rt->target.s_net) { 528 if (!(rt->flags & RTF_HOST)) 529 break; 530 if (ta->sat_addr.s_node == rt->target.s_node) 531 break; 532 } 533 } 534 535 if (!devhint) { 536 riface = NULL; 537 538 read_lock_bh(&atalk_interfaces_lock); 539 for (iface = atalk_interfaces; iface; iface = iface->next) { 540 if (!riface && 541 ntohs(ga->sat_addr.s_net) >= 542 ntohs(iface->nets.nr_firstnet) && 543 ntohs(ga->sat_addr.s_net) <= 544 ntohs(iface->nets.nr_lastnet)) 545 riface = iface; 546 547 if (ga->sat_addr.s_net == iface->address.s_net && 548 ga->sat_addr.s_node == iface->address.s_node) 549 riface = iface; 550 } 551 read_unlock_bh(&atalk_interfaces_lock); 552 553 retval = -ENETUNREACH; 554 if (!riface) 555 goto out_unlock; 556 557 devhint = riface->dev; 558 } 559 560 if (!rt) { 561 rt = kzalloc(sizeof(*rt), GFP_ATOMIC); 562 563 retval = -ENOBUFS; 564 if (!rt) 565 goto out_unlock; 566 567 rt->next = atalk_routes; 568 atalk_routes = rt; 569 } 570 571 /* Fill in the routing entry */ 572 rt->target = ta->sat_addr; 573 dev_hold(devhint); 574 rt->dev = devhint; 575 rt->flags = r->rt_flags; 576 rt->gateway = ga->sat_addr; 577 578 retval = 0; 579 out_unlock: 580 write_unlock_bh(&atalk_routes_lock); 581 out: 582 return retval; 583 } 584 585 /* Delete a route. Find it and discard it */ 586 static int atrtr_delete(struct atalk_addr * addr) 587 { 588 struct atalk_route **r = &atalk_routes; 589 int retval = 0; 590 struct atalk_route *tmp; 591 592 write_lock_bh(&atalk_routes_lock); 593 while ((tmp = *r) != NULL) { 594 if (tmp->target.s_net == addr->s_net && 595 (!(tmp->flags&RTF_GATEWAY) || 596 tmp->target.s_node == addr->s_node)) { 597 *r = tmp->next; 598 dev_put(tmp->dev); 599 kfree(tmp); 600 goto out; 601 } 602 r = &tmp->next; 603 } 604 retval = -ENOENT; 605 out: 606 write_unlock_bh(&atalk_routes_lock); 607 return retval; 608 } 609 610 /* 611 * Called when a device is downed. Just throw away any routes 612 * via it. 613 */ 614 static void atrtr_device_down(struct net_device *dev) 615 { 616 struct atalk_route **r = &atalk_routes; 617 struct atalk_route *tmp; 618 619 write_lock_bh(&atalk_routes_lock); 620 while ((tmp = *r) != NULL) { 621 if (tmp->dev == dev) { 622 *r = tmp->next; 623 dev_put(dev); 624 kfree(tmp); 625 } else 626 r = &tmp->next; 627 } 628 write_unlock_bh(&atalk_routes_lock); 629 630 if (atrtr_default.dev == dev) 631 atrtr_set_default(NULL); 632 } 633 634 /* Actually down the interface */ 635 static inline void atalk_dev_down(struct net_device *dev) 636 { 637 atrtr_device_down(dev); /* Remove all routes for the device */ 638 aarp_device_down(dev); /* Remove AARP entries for the device */ 639 atif_drop_device(dev); /* Remove the device */ 640 } 641 642 /* 643 * A device event has occurred. Watch for devices going down and 644 * delete our use of them (iface and route). 645 */ 646 static int ddp_device_event(struct notifier_block *this, unsigned long event, 647 void *ptr) 648 { 649 struct net_device *dev = ptr; 650 651 if (!net_eq(dev_net(dev), &init_net)) 652 return NOTIFY_DONE; 653 654 if (event == NETDEV_DOWN) 655 /* Discard any use of this */ 656 atalk_dev_down(dev); 657 658 return NOTIFY_DONE; 659 } 660 661 /* ioctl calls. Shouldn't even need touching */ 662 /* Device configuration ioctl calls */ 663 static int atif_ioctl(int cmd, void __user *arg) 664 { 665 static char aarp_mcast[6] = { 0x09, 0x00, 0x00, 0xFF, 0xFF, 0xFF }; 666 struct ifreq atreq; 667 struct atalk_netrange *nr; 668 struct sockaddr_at *sa; 669 struct net_device *dev; 670 struct atalk_iface *atif; 671 int ct; 672 int limit; 673 struct rtentry rtdef; 674 int add_route; 675 676 if (copy_from_user(&atreq, arg, sizeof(atreq))) 677 return -EFAULT; 678 679 dev = __dev_get_by_name(&init_net, atreq.ifr_name); 680 if (!dev) 681 return -ENODEV; 682 683 sa = (struct sockaddr_at *)&atreq.ifr_addr; 684 atif = atalk_find_dev(dev); 685 686 switch (cmd) { 687 case SIOCSIFADDR: 688 if (!capable(CAP_NET_ADMIN)) 689 return -EPERM; 690 if (sa->sat_family != AF_APPLETALK) 691 return -EINVAL; 692 if (dev->type != ARPHRD_ETHER && 693 dev->type != ARPHRD_LOOPBACK && 694 dev->type != ARPHRD_LOCALTLK && 695 dev->type != ARPHRD_PPP) 696 return -EPROTONOSUPPORT; 697 698 nr = (struct atalk_netrange *)&sa->sat_zero[0]; 699 add_route = 1; 700 701 /* 702 * if this is a point-to-point iface, and we already 703 * have an iface for this AppleTalk address, then we 704 * should not add a route 705 */ 706 if ((dev->flags & IFF_POINTOPOINT) && 707 atalk_find_interface(sa->sat_addr.s_net, 708 sa->sat_addr.s_node)) { 709 printk(KERN_DEBUG "AppleTalk: point-to-point " 710 "interface added with " 711 "existing address\n"); 712 add_route = 0; 713 } 714 715 /* 716 * Phase 1 is fine on LocalTalk but we don't do 717 * EtherTalk phase 1. Anyone wanting to add it go ahead. 718 */ 719 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2) 720 return -EPROTONOSUPPORT; 721 if (sa->sat_addr.s_node == ATADDR_BCAST || 722 sa->sat_addr.s_node == 254) 723 return -EINVAL; 724 if (atif) { 725 /* Already setting address */ 726 if (atif->status & ATIF_PROBE) 727 return -EBUSY; 728 729 atif->address.s_net = sa->sat_addr.s_net; 730 atif->address.s_node = sa->sat_addr.s_node; 731 atrtr_device_down(dev); /* Flush old routes */ 732 } else { 733 atif = atif_add_device(dev, &sa->sat_addr); 734 if (!atif) 735 return -ENOMEM; 736 } 737 atif->nets = *nr; 738 739 /* 740 * Check if the chosen address is used. If so we 741 * error and atalkd will try another. 742 */ 743 744 if (!(dev->flags & IFF_LOOPBACK) && 745 !(dev->flags & IFF_POINTOPOINT) && 746 atif_probe_device(atif) < 0) { 747 atif_drop_device(dev); 748 return -EADDRINUSE; 749 } 750 751 /* Hey it worked - add the direct routes */ 752 sa = (struct sockaddr_at *)&rtdef.rt_gateway; 753 sa->sat_family = AF_APPLETALK; 754 sa->sat_addr.s_net = atif->address.s_net; 755 sa->sat_addr.s_node = atif->address.s_node; 756 sa = (struct sockaddr_at *)&rtdef.rt_dst; 757 rtdef.rt_flags = RTF_UP; 758 sa->sat_family = AF_APPLETALK; 759 sa->sat_addr.s_node = ATADDR_ANYNODE; 760 if (dev->flags & IFF_LOOPBACK || 761 dev->flags & IFF_POINTOPOINT) 762 rtdef.rt_flags |= RTF_HOST; 763 764 /* Routerless initial state */ 765 if (nr->nr_firstnet == htons(0) && 766 nr->nr_lastnet == htons(0xFFFE)) { 767 sa->sat_addr.s_net = atif->address.s_net; 768 atrtr_create(&rtdef, dev); 769 atrtr_set_default(dev); 770 } else { 771 limit = ntohs(nr->nr_lastnet); 772 if (limit - ntohs(nr->nr_firstnet) > 4096) { 773 printk(KERN_WARNING "Too many routes/" 774 "iface.\n"); 775 return -EINVAL; 776 } 777 if (add_route) 778 for (ct = ntohs(nr->nr_firstnet); 779 ct <= limit; ct++) { 780 sa->sat_addr.s_net = htons(ct); 781 atrtr_create(&rtdef, dev); 782 } 783 } 784 dev_mc_add(dev, aarp_mcast, 6, 1); 785 return 0; 786 787 case SIOCGIFADDR: 788 if (!atif) 789 return -EADDRNOTAVAIL; 790 791 sa->sat_family = AF_APPLETALK; 792 sa->sat_addr = atif->address; 793 break; 794 795 case SIOCGIFBRDADDR: 796 if (!atif) 797 return -EADDRNOTAVAIL; 798 799 sa->sat_family = AF_APPLETALK; 800 sa->sat_addr.s_net = atif->address.s_net; 801 sa->sat_addr.s_node = ATADDR_BCAST; 802 break; 803 804 case SIOCATALKDIFADDR: 805 case SIOCDIFADDR: 806 if (!capable(CAP_NET_ADMIN)) 807 return -EPERM; 808 if (sa->sat_family != AF_APPLETALK) 809 return -EINVAL; 810 atalk_dev_down(dev); 811 break; 812 813 case SIOCSARP: 814 if (!capable(CAP_NET_ADMIN)) 815 return -EPERM; 816 if (sa->sat_family != AF_APPLETALK) 817 return -EINVAL; 818 /* 819 * for now, we only support proxy AARP on ELAP; 820 * we should be able to do it for LocalTalk, too. 821 */ 822 if (dev->type != ARPHRD_ETHER) 823 return -EPROTONOSUPPORT; 824 825 /* 826 * atif points to the current interface on this network; 827 * we aren't concerned about its current status (at 828 * least for now), but it has all the settings about 829 * the network we're going to probe. Consequently, it 830 * must exist. 831 */ 832 if (!atif) 833 return -EADDRNOTAVAIL; 834 835 nr = (struct atalk_netrange *)&(atif->nets); 836 /* 837 * Phase 1 is fine on Localtalk but we don't do 838 * Ethertalk phase 1. Anyone wanting to add it go ahead. 839 */ 840 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2) 841 return -EPROTONOSUPPORT; 842 843 if (sa->sat_addr.s_node == ATADDR_BCAST || 844 sa->sat_addr.s_node == 254) 845 return -EINVAL; 846 847 /* 848 * Check if the chosen address is used. If so we 849 * error and ATCP will try another. 850 */ 851 if (atif_proxy_probe_device(atif, &(sa->sat_addr)) < 0) 852 return -EADDRINUSE; 853 854 /* 855 * We now have an address on the local network, and 856 * the AARP code will defend it for us until we take it 857 * down. We don't set up any routes right now, because 858 * ATCP will install them manually via SIOCADDRT. 859 */ 860 break; 861 862 case SIOCDARP: 863 if (!capable(CAP_NET_ADMIN)) 864 return -EPERM; 865 if (sa->sat_family != AF_APPLETALK) 866 return -EINVAL; 867 if (!atif) 868 return -EADDRNOTAVAIL; 869 870 /* give to aarp module to remove proxy entry */ 871 aarp_proxy_remove(atif->dev, &(sa->sat_addr)); 872 return 0; 873 } 874 875 return copy_to_user(arg, &atreq, sizeof(atreq)) ? -EFAULT : 0; 876 } 877 878 /* Routing ioctl() calls */ 879 static int atrtr_ioctl(unsigned int cmd, void __user *arg) 880 { 881 struct rtentry rt; 882 883 if (copy_from_user(&rt, arg, sizeof(rt))) 884 return -EFAULT; 885 886 switch (cmd) { 887 case SIOCDELRT: 888 if (rt.rt_dst.sa_family != AF_APPLETALK) 889 return -EINVAL; 890 return atrtr_delete(&((struct sockaddr_at *) 891 &rt.rt_dst)->sat_addr); 892 893 case SIOCADDRT: { 894 struct net_device *dev = NULL; 895 if (rt.rt_dev) { 896 char name[IFNAMSIZ]; 897 if (copy_from_user(name, rt.rt_dev, IFNAMSIZ-1)) 898 return -EFAULT; 899 name[IFNAMSIZ-1] = '\0'; 900 dev = __dev_get_by_name(&init_net, name); 901 if (!dev) 902 return -ENODEV; 903 } 904 return atrtr_create(&rt, dev); 905 } 906 } 907 return -EINVAL; 908 } 909 910 /**************************************************************************\ 911 * * 912 * Handling for system calls applied via the various interfaces to an * 913 * AppleTalk socket object. * 914 * * 915 \**************************************************************************/ 916 917 /* 918 * Checksum: This is 'optional'. It's quite likely also a good 919 * candidate for assembler hackery 8) 920 */ 921 static unsigned long atalk_sum_partial(const unsigned char *data, 922 int len, unsigned long sum) 923 { 924 /* This ought to be unwrapped neatly. I'll trust gcc for now */ 925 while (len--) { 926 sum += *data++; 927 sum = rol16(sum, 1); 928 } 929 return sum; 930 } 931 932 /* Checksum skb data -- similar to skb_checksum */ 933 static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, 934 int len, unsigned long sum) 935 { 936 int start = skb_headlen(skb); 937 struct sk_buff *frag_iter; 938 int i, copy; 939 940 /* checksum stuff in header space */ 941 if ( (copy = start - offset) > 0) { 942 if (copy > len) 943 copy = len; 944 sum = atalk_sum_partial(skb->data + offset, copy, sum); 945 if ( (len -= copy) == 0) 946 return sum; 947 948 offset += copy; 949 } 950 951 /* checksum stuff in frags */ 952 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 953 int end; 954 955 WARN_ON(start > offset + len); 956 957 end = start + skb_shinfo(skb)->frags[i].size; 958 if ((copy = end - offset) > 0) { 959 u8 *vaddr; 960 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 961 962 if (copy > len) 963 copy = len; 964 vaddr = kmap_skb_frag(frag); 965 sum = atalk_sum_partial(vaddr + frag->page_offset + 966 offset - start, copy, sum); 967 kunmap_skb_frag(vaddr); 968 969 if (!(len -= copy)) 970 return sum; 971 offset += copy; 972 } 973 start = end; 974 } 975 976 skb_walk_frags(skb, frag_iter) { 977 int end; 978 979 WARN_ON(start > offset + len); 980 981 end = start + frag_iter->len; 982 if ((copy = end - offset) > 0) { 983 if (copy > len) 984 copy = len; 985 sum = atalk_sum_skb(frag_iter, offset - start, 986 copy, sum); 987 if ((len -= copy) == 0) 988 return sum; 989 offset += copy; 990 } 991 start = end; 992 } 993 994 BUG_ON(len > 0); 995 996 return sum; 997 } 998 999 static __be16 atalk_checksum(const struct sk_buff *skb, int len) 1000 { 1001 unsigned long sum; 1002 1003 /* skip header 4 bytes */ 1004 sum = atalk_sum_skb(skb, 4, len-4, 0); 1005 1006 /* Use 0xFFFF for 0. 0 itself means none */ 1007 return sum ? htons((unsigned short)sum) : htons(0xFFFF); 1008 } 1009 1010 static struct proto ddp_proto = { 1011 .name = "DDP", 1012 .owner = THIS_MODULE, 1013 .obj_size = sizeof(struct atalk_sock), 1014 }; 1015 1016 /* 1017 * Create a socket. Initialise the socket, blank the addresses 1018 * set the state. 1019 */ 1020 static int atalk_create(struct net *net, struct socket *sock, int protocol, 1021 int kern) 1022 { 1023 struct sock *sk; 1024 int rc = -ESOCKTNOSUPPORT; 1025 1026 if (!net_eq(net, &init_net)) 1027 return -EAFNOSUPPORT; 1028 1029 /* 1030 * We permit SOCK_DGRAM and RAW is an extension. It is trivial to do 1031 * and gives you the full ELAP frame. Should be handy for CAP 8) 1032 */ 1033 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) 1034 goto out; 1035 rc = -ENOMEM; 1036 sk = sk_alloc(net, PF_APPLETALK, GFP_KERNEL, &ddp_proto); 1037 if (!sk) 1038 goto out; 1039 rc = 0; 1040 sock->ops = &atalk_dgram_ops; 1041 sock_init_data(sock, sk); 1042 1043 /* Checksums on by default */ 1044 sock_set_flag(sk, SOCK_ZAPPED); 1045 out: 1046 return rc; 1047 } 1048 1049 /* Free a socket. No work needed */ 1050 static int atalk_release(struct socket *sock) 1051 { 1052 struct sock *sk = sock->sk; 1053 1054 lock_kernel(); 1055 if (sk) { 1056 sock_orphan(sk); 1057 sock->sk = NULL; 1058 atalk_destroy_socket(sk); 1059 } 1060 unlock_kernel(); 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 struct hlist_node *node; 1085 1086 sk_for_each(s, node, &atalk_sockets) { 1087 struct atalk_sock *at = at_sk(s); 1088 1089 if (at->src_net == sat->sat_addr.s_net && 1090 at->src_node == sat->sat_addr.s_node && 1091 at->src_port == sat->sat_port) 1092 goto try_next_port; 1093 } 1094 1095 /* Wheee, it's free, assign and insert. */ 1096 __atalk_insert_socket(sk); 1097 at_sk(sk)->src_port = sat->sat_port; 1098 retval = 0; 1099 goto out; 1100 1101 try_next_port:; 1102 } 1103 1104 retval = -EBUSY; 1105 out: 1106 write_unlock_bh(&atalk_sockets_lock); 1107 return retval; 1108 } 1109 1110 static int atalk_autobind(struct sock *sk) 1111 { 1112 struct atalk_sock *at = at_sk(sk); 1113 struct sockaddr_at sat; 1114 struct atalk_addr *ap = atalk_find_primary(); 1115 int n = -EADDRNOTAVAIL; 1116 1117 if (!ap || ap->s_net == htons(ATADDR_ANYNET)) 1118 goto out; 1119 1120 at->src_net = sat.sat_addr.s_net = ap->s_net; 1121 at->src_node = sat.sat_addr.s_node = ap->s_node; 1122 1123 n = atalk_pick_and_bind_port(sk, &sat); 1124 if (!n) 1125 sock_reset_flag(sk, SOCK_ZAPPED); 1126 out: 1127 return n; 1128 } 1129 1130 /* Set the address 'our end' of the connection */ 1131 static int atalk_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 1132 { 1133 struct sockaddr_at *addr = (struct sockaddr_at *)uaddr; 1134 struct sock *sk = sock->sk; 1135 struct atalk_sock *at = at_sk(sk); 1136 int err; 1137 1138 if (!sock_flag(sk, SOCK_ZAPPED) || 1139 addr_len != sizeof(struct sockaddr_at)) 1140 return -EINVAL; 1141 1142 if (addr->sat_family != AF_APPLETALK) 1143 return -EAFNOSUPPORT; 1144 1145 lock_kernel(); 1146 if (addr->sat_addr.s_net == htons(ATADDR_ANYNET)) { 1147 struct atalk_addr *ap = atalk_find_primary(); 1148 1149 err = -EADDRNOTAVAIL; 1150 if (!ap) 1151 goto out; 1152 1153 at->src_net = addr->sat_addr.s_net = ap->s_net; 1154 at->src_node = addr->sat_addr.s_node= ap->s_node; 1155 } else { 1156 err = -EADDRNOTAVAIL; 1157 if (!atalk_find_interface(addr->sat_addr.s_net, 1158 addr->sat_addr.s_node)) 1159 goto out; 1160 1161 at->src_net = addr->sat_addr.s_net; 1162 at->src_node = addr->sat_addr.s_node; 1163 } 1164 1165 if (addr->sat_port == ATADDR_ANYPORT) { 1166 err = atalk_pick_and_bind_port(sk, addr); 1167 1168 if (err < 0) 1169 goto out; 1170 } else { 1171 at->src_port = addr->sat_port; 1172 1173 err = -EADDRINUSE; 1174 if (atalk_find_or_insert_socket(sk, addr)) 1175 goto out; 1176 } 1177 1178 sock_reset_flag(sk, SOCK_ZAPPED); 1179 err = 0; 1180 out: 1181 unlock_kernel(); 1182 return err; 1183 } 1184 1185 /* Set the address we talk to */ 1186 static int atalk_connect(struct socket *sock, struct sockaddr *uaddr, 1187 int addr_len, int flags) 1188 { 1189 struct sock *sk = sock->sk; 1190 struct atalk_sock *at = at_sk(sk); 1191 struct sockaddr_at *addr; 1192 int err; 1193 1194 sk->sk_state = TCP_CLOSE; 1195 sock->state = SS_UNCONNECTED; 1196 1197 if (addr_len != sizeof(*addr)) 1198 return -EINVAL; 1199 1200 addr = (struct sockaddr_at *)uaddr; 1201 1202 if (addr->sat_family != AF_APPLETALK) 1203 return -EAFNOSUPPORT; 1204 1205 if (addr->sat_addr.s_node == ATADDR_BCAST && 1206 !sock_flag(sk, SOCK_BROADCAST)) { 1207 #if 1 1208 printk(KERN_WARNING "%s is broken and did not set " 1209 "SO_BROADCAST. It will break when 2.2 is " 1210 "released.\n", 1211 current->comm); 1212 #else 1213 return -EACCES; 1214 #endif 1215 } 1216 1217 lock_kernel(); 1218 err = -EBUSY; 1219 if (sock_flag(sk, SOCK_ZAPPED)) 1220 if (atalk_autobind(sk) < 0) 1221 goto out; 1222 1223 err = -ENETUNREACH; 1224 if (!atrtr_get_dev(&addr->sat_addr)) 1225 goto out; 1226 1227 at->dest_port = addr->sat_port; 1228 at->dest_net = addr->sat_addr.s_net; 1229 at->dest_node = addr->sat_addr.s_node; 1230 1231 sock->state = SS_CONNECTED; 1232 sk->sk_state = TCP_ESTABLISHED; 1233 err = 0; 1234 out: 1235 unlock_kernel(); 1236 return err; 1237 } 1238 1239 /* 1240 * Find the name of an AppleTalk socket. Just copy the right 1241 * fields into the sockaddr. 1242 */ 1243 static int atalk_getname(struct socket *sock, struct sockaddr *uaddr, 1244 int *uaddr_len, int peer) 1245 { 1246 struct sockaddr_at sat; 1247 struct sock *sk = sock->sk; 1248 struct atalk_sock *at = at_sk(sk); 1249 int err; 1250 1251 lock_kernel(); 1252 err = -ENOBUFS; 1253 if (sock_flag(sk, SOCK_ZAPPED)) 1254 if (atalk_autobind(sk) < 0) 1255 goto out; 1256 1257 *uaddr_len = sizeof(struct sockaddr_at); 1258 memset(&sat.sat_zero, 0, sizeof(sat.sat_zero)); 1259 1260 if (peer) { 1261 err = -ENOTCONN; 1262 if (sk->sk_state != TCP_ESTABLISHED) 1263 goto out; 1264 1265 sat.sat_addr.s_net = at->dest_net; 1266 sat.sat_addr.s_node = at->dest_node; 1267 sat.sat_port = at->dest_port; 1268 } else { 1269 sat.sat_addr.s_net = at->src_net; 1270 sat.sat_addr.s_node = at->src_node; 1271 sat.sat_port = at->src_port; 1272 } 1273 1274 err = 0; 1275 sat.sat_family = AF_APPLETALK; 1276 memcpy(uaddr, &sat, sizeof(sat)); 1277 1278 out: 1279 unlock_kernel(); 1280 return err; 1281 } 1282 1283 static unsigned int atalk_poll(struct file *file, struct socket *sock, 1284 poll_table *wait) 1285 { 1286 int err; 1287 lock_kernel(); 1288 err = datagram_poll(file, sock, wait); 1289 unlock_kernel(); 1290 return err; 1291 } 1292 1293 #if defined(CONFIG_IPDDP) || defined(CONFIG_IPDDP_MODULE) 1294 static __inline__ int is_ip_over_ddp(struct sk_buff *skb) 1295 { 1296 return skb->data[12] == 22; 1297 } 1298 1299 static int handle_ip_over_ddp(struct sk_buff *skb) 1300 { 1301 struct net_device *dev = __dev_get_by_name(&init_net, "ipddp0"); 1302 struct net_device_stats *stats; 1303 1304 /* This needs to be able to handle ipddp"N" devices */ 1305 if (!dev) { 1306 kfree_skb(skb); 1307 return NET_RX_DROP; 1308 } 1309 1310 skb->protocol = htons(ETH_P_IP); 1311 skb_pull(skb, 13); 1312 skb->dev = dev; 1313 skb_reset_transport_header(skb); 1314 1315 stats = netdev_priv(dev); 1316 stats->rx_packets++; 1317 stats->rx_bytes += skb->len + 13; 1318 return netif_rx(skb); /* Send the SKB up to a higher place. */ 1319 } 1320 #else 1321 /* make it easy for gcc to optimize this test out, i.e. kill the code */ 1322 #define is_ip_over_ddp(skb) 0 1323 #define handle_ip_over_ddp(skb) 0 1324 #endif 1325 1326 static int atalk_route_packet(struct sk_buff *skb, struct net_device *dev, 1327 struct ddpehdr *ddp, __u16 len_hops, int origlen) 1328 { 1329 struct atalk_route *rt; 1330 struct atalk_addr ta; 1331 1332 /* 1333 * Don't route multicast, etc., packets, or packets sent to "this 1334 * network" 1335 */ 1336 if (skb->pkt_type != PACKET_HOST || !ddp->deh_dnet) { 1337 /* 1338 * FIXME: 1339 * 1340 * Can it ever happen that a packet is from a PPP iface and 1341 * needs to be broadcast onto the default network? 1342 */ 1343 if (dev->type == ARPHRD_PPP) 1344 printk(KERN_DEBUG "AppleTalk: didn't forward broadcast " 1345 "packet received from PPP iface\n"); 1346 goto free_it; 1347 } 1348 1349 ta.s_net = ddp->deh_dnet; 1350 ta.s_node = ddp->deh_dnode; 1351 1352 /* Route the packet */ 1353 rt = atrtr_find(&ta); 1354 /* increment hops count */ 1355 len_hops += 1 << 10; 1356 if (!rt || !(len_hops & (15 << 10))) 1357 goto free_it; 1358 1359 /* FIXME: use skb->cb to be able to use shared skbs */ 1360 1361 /* 1362 * Route goes through another gateway, so set the target to the 1363 * gateway instead. 1364 */ 1365 1366 if (rt->flags & RTF_GATEWAY) { 1367 ta.s_net = rt->gateway.s_net; 1368 ta.s_node = rt->gateway.s_node; 1369 } 1370 1371 /* Fix up skb->len field */ 1372 skb_trim(skb, min_t(unsigned int, origlen, 1373 (rt->dev->hard_header_len + 1374 ddp_dl->header_length + (len_hops & 1023)))); 1375 1376 /* FIXME: use skb->cb to be able to use shared skbs */ 1377 ddp->deh_len_hops = htons(len_hops); 1378 1379 /* 1380 * Send the buffer onwards 1381 * 1382 * Now we must always be careful. If it's come from LocalTalk to 1383 * EtherTalk it might not fit 1384 * 1385 * Order matters here: If a packet has to be copied to make a new 1386 * headroom (rare hopefully) then it won't need unsharing. 1387 * 1388 * Note. ddp-> becomes invalid at the realloc. 1389 */ 1390 if (skb_headroom(skb) < 22) { 1391 /* 22 bytes - 12 ether, 2 len, 3 802.2 5 snap */ 1392 struct sk_buff *nskb = skb_realloc_headroom(skb, 32); 1393 kfree_skb(skb); 1394 skb = nskb; 1395 } else 1396 skb = skb_unshare(skb, GFP_ATOMIC); 1397 1398 /* 1399 * If the buffer didn't vanish into the lack of space bitbucket we can 1400 * send it. 1401 */ 1402 if (skb == NULL) 1403 goto drop; 1404 1405 if (aarp_send_ddp(rt->dev, skb, &ta, NULL) == NET_XMIT_DROP) 1406 return NET_RX_DROP; 1407 return NET_RX_SUCCESS; 1408 free_it: 1409 kfree_skb(skb); 1410 drop: 1411 return NET_RX_DROP; 1412 } 1413 1414 /** 1415 * atalk_rcv - Receive a packet (in skb) from device dev 1416 * @skb - packet received 1417 * @dev - network device where the packet comes from 1418 * @pt - packet type 1419 * 1420 * Receive a packet (in skb) from device dev. This has come from the SNAP 1421 * decoder, and on entry skb->transport_header is the DDP header, skb->len 1422 * is the DDP header, skb->len is the DDP length. The physical headers 1423 * have been extracted. PPP should probably pass frames marked as for this 1424 * layer. [ie ARPHRD_ETHERTALK] 1425 */ 1426 static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 1427 struct packet_type *pt, struct net_device *orig_dev) 1428 { 1429 struct ddpehdr *ddp; 1430 struct sock *sock; 1431 struct atalk_iface *atif; 1432 struct sockaddr_at tosat; 1433 int origlen; 1434 __u16 len_hops; 1435 1436 if (!net_eq(dev_net(dev), &init_net)) 1437 goto drop; 1438 1439 /* Don't mangle buffer if shared */ 1440 if (!(skb = skb_share_check(skb, GFP_ATOMIC))) 1441 goto out; 1442 1443 /* Size check and make sure header is contiguous */ 1444 if (!pskb_may_pull(skb, sizeof(*ddp))) 1445 goto drop; 1446 1447 ddp = ddp_hdr(skb); 1448 1449 len_hops = ntohs(ddp->deh_len_hops); 1450 1451 /* Trim buffer in case of stray trailing data */ 1452 origlen = skb->len; 1453 skb_trim(skb, min_t(unsigned int, skb->len, len_hops & 1023)); 1454 1455 /* 1456 * Size check to see if ddp->deh_len was crap 1457 * (Otherwise we'll detonate most spectacularly 1458 * in the middle of atalk_checksum() or recvmsg()). 1459 */ 1460 if (skb->len < sizeof(*ddp) || skb->len < (len_hops & 1023)) { 1461 pr_debug("AppleTalk: dropping corrupted frame (deh_len=%u, " 1462 "skb->len=%u)\n", len_hops & 1023, skb->len); 1463 goto drop; 1464 } 1465 1466 /* 1467 * Any checksums. Note we don't do htons() on this == is assumed to be 1468 * valid for net byte orders all over the networking code... 1469 */ 1470 if (ddp->deh_sum && 1471 atalk_checksum(skb, len_hops & 1023) != ddp->deh_sum) 1472 /* Not a valid AppleTalk frame - dustbin time */ 1473 goto drop; 1474 1475 /* Check the packet is aimed at us */ 1476 if (!ddp->deh_dnet) /* Net 0 is 'this network' */ 1477 atif = atalk_find_anynet(ddp->deh_dnode, dev); 1478 else 1479 atif = atalk_find_interface(ddp->deh_dnet, ddp->deh_dnode); 1480 1481 if (!atif) { 1482 /* Not ours, so we route the packet via the correct 1483 * AppleTalk iface 1484 */ 1485 return atalk_route_packet(skb, dev, ddp, len_hops, origlen); 1486 } 1487 1488 /* if IP over DDP is not selected this code will be optimized out */ 1489 if (is_ip_over_ddp(skb)) 1490 return handle_ip_over_ddp(skb); 1491 /* 1492 * Which socket - atalk_search_socket() looks for a *full match* 1493 * of the <net, node, port> tuple. 1494 */ 1495 tosat.sat_addr.s_net = ddp->deh_dnet; 1496 tosat.sat_addr.s_node = ddp->deh_dnode; 1497 tosat.sat_port = ddp->deh_dport; 1498 1499 sock = atalk_search_socket(&tosat, atif); 1500 if (!sock) /* But not one of our sockets */ 1501 goto drop; 1502 1503 /* Queue packet (standard) */ 1504 skb->sk = sock; 1505 1506 if (sock_queue_rcv_skb(sock, skb) < 0) 1507 goto drop; 1508 1509 return NET_RX_SUCCESS; 1510 1511 drop: 1512 kfree_skb(skb); 1513 out: 1514 return NET_RX_DROP; 1515 1516 } 1517 1518 /* 1519 * Receive a LocalTalk frame. We make some demands on the caller here. 1520 * Caller must provide enough headroom on the packet to pull the short 1521 * header and append a long one. 1522 */ 1523 static int ltalk_rcv(struct sk_buff *skb, struct net_device *dev, 1524 struct packet_type *pt, struct net_device *orig_dev) 1525 { 1526 if (!net_eq(dev_net(dev), &init_net)) 1527 goto freeit; 1528 1529 /* Expand any short form frames */ 1530 if (skb_mac_header(skb)[2] == 1) { 1531 struct ddpehdr *ddp; 1532 /* Find our address */ 1533 struct atalk_addr *ap = atalk_find_dev_addr(dev); 1534 1535 if (!ap || skb->len < sizeof(__be16) || skb->len > 1023) 1536 goto freeit; 1537 1538 /* Don't mangle buffer if shared */ 1539 if (!(skb = skb_share_check(skb, GFP_ATOMIC))) 1540 return 0; 1541 1542 /* 1543 * The push leaves us with a ddephdr not an shdr, and 1544 * handily the port bytes in the right place preset. 1545 */ 1546 ddp = (struct ddpehdr *) skb_push(skb, sizeof(*ddp) - 4); 1547 1548 /* Now fill in the long header */ 1549 1550 /* 1551 * These two first. The mac overlays the new source/dest 1552 * network information so we MUST copy these before 1553 * we write the network numbers ! 1554 */ 1555 1556 ddp->deh_dnode = skb_mac_header(skb)[0]; /* From physical header */ 1557 ddp->deh_snode = skb_mac_header(skb)[1]; /* From physical header */ 1558 1559 ddp->deh_dnet = ap->s_net; /* Network number */ 1560 ddp->deh_snet = ap->s_net; 1561 ddp->deh_sum = 0; /* No checksum */ 1562 /* 1563 * Not sure about this bit... 1564 */ 1565 /* Non routable, so force a drop if we slip up later */ 1566 ddp->deh_len_hops = htons(skb->len + (DDP_MAXHOPS << 10)); 1567 } 1568 skb_reset_transport_header(skb); 1569 1570 return atalk_rcv(skb, dev, pt, orig_dev); 1571 freeit: 1572 kfree_skb(skb); 1573 return 0; 1574 } 1575 1576 static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, 1577 size_t len) 1578 { 1579 struct sock *sk = sock->sk; 1580 struct atalk_sock *at = at_sk(sk); 1581 struct sockaddr_at *usat = (struct sockaddr_at *)msg->msg_name; 1582 int flags = msg->msg_flags; 1583 int loopback = 0; 1584 struct sockaddr_at local_satalk, gsat; 1585 struct sk_buff *skb; 1586 struct net_device *dev; 1587 struct ddpehdr *ddp; 1588 int size; 1589 struct atalk_route *rt; 1590 int err; 1591 1592 if (flags & ~(MSG_DONTWAIT|MSG_CMSG_COMPAT)) 1593 return -EINVAL; 1594 1595 if (len > DDP_MAXSZ) 1596 return -EMSGSIZE; 1597 1598 lock_kernel(); 1599 if (usat) { 1600 err = -EBUSY; 1601 if (sock_flag(sk, SOCK_ZAPPED)) 1602 if (atalk_autobind(sk) < 0) 1603 goto out; 1604 1605 err = -EINVAL; 1606 if (msg->msg_namelen < sizeof(*usat) || 1607 usat->sat_family != AF_APPLETALK) 1608 goto out; 1609 1610 err = -EPERM; 1611 /* netatalk didn't implement this check */ 1612 if (usat->sat_addr.s_node == ATADDR_BCAST && 1613 !sock_flag(sk, SOCK_BROADCAST)) { 1614 goto out; 1615 } 1616 } else { 1617 err = -ENOTCONN; 1618 if (sk->sk_state != TCP_ESTABLISHED) 1619 goto out; 1620 usat = &local_satalk; 1621 usat->sat_family = AF_APPLETALK; 1622 usat->sat_port = at->dest_port; 1623 usat->sat_addr.s_node = at->dest_node; 1624 usat->sat_addr.s_net = at->dest_net; 1625 } 1626 1627 /* Build a packet */ 1628 SOCK_DEBUG(sk, "SK %p: Got address.\n", sk); 1629 1630 /* For headers */ 1631 size = sizeof(struct ddpehdr) + len + ddp_dl->header_length; 1632 1633 if (usat->sat_addr.s_net || usat->sat_addr.s_node == ATADDR_ANYNODE) { 1634 rt = atrtr_find(&usat->sat_addr); 1635 } else { 1636 struct atalk_addr at_hint; 1637 1638 at_hint.s_node = 0; 1639 at_hint.s_net = at->src_net; 1640 1641 rt = atrtr_find(&at_hint); 1642 } 1643 err = ENETUNREACH; 1644 if (!rt) 1645 goto out; 1646 1647 dev = rt->dev; 1648 1649 SOCK_DEBUG(sk, "SK %p: Size needed %d, device %s\n", 1650 sk, size, dev->name); 1651 1652 size += dev->hard_header_len; 1653 skb = sock_alloc_send_skb(sk, size, (flags & MSG_DONTWAIT), &err); 1654 if (!skb) 1655 goto out; 1656 1657 skb->sk = sk; 1658 skb_reserve(skb, ddp_dl->header_length); 1659 skb_reserve(skb, dev->hard_header_len); 1660 skb->dev = dev; 1661 1662 SOCK_DEBUG(sk, "SK %p: Begin build.\n", sk); 1663 1664 ddp = (struct ddpehdr *)skb_put(skb, sizeof(struct ddpehdr)); 1665 ddp->deh_len_hops = htons(len + sizeof(*ddp)); 1666 ddp->deh_dnet = usat->sat_addr.s_net; 1667 ddp->deh_snet = at->src_net; 1668 ddp->deh_dnode = usat->sat_addr.s_node; 1669 ddp->deh_snode = at->src_node; 1670 ddp->deh_dport = usat->sat_port; 1671 ddp->deh_sport = at->src_port; 1672 1673 SOCK_DEBUG(sk, "SK %p: Copy user data (%Zd bytes).\n", sk, len); 1674 1675 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 1676 if (err) { 1677 kfree_skb(skb); 1678 err = -EFAULT; 1679 goto out; 1680 } 1681 1682 if (sk->sk_no_check == 1) 1683 ddp->deh_sum = 0; 1684 else 1685 ddp->deh_sum = atalk_checksum(skb, len + sizeof(*ddp)); 1686 1687 /* 1688 * Loopback broadcast packets to non gateway targets (ie routes 1689 * to group we are in) 1690 */ 1691 if (ddp->deh_dnode == ATADDR_BCAST && 1692 !(rt->flags & RTF_GATEWAY) && !(dev->flags & IFF_LOOPBACK)) { 1693 struct sk_buff *skb2 = skb_copy(skb, GFP_KERNEL); 1694 1695 if (skb2) { 1696 loopback = 1; 1697 SOCK_DEBUG(sk, "SK %p: send out(copy).\n", sk); 1698 /* 1699 * If it fails it is queued/sent above in the aarp queue 1700 */ 1701 aarp_send_ddp(dev, skb2, &usat->sat_addr, NULL); 1702 } 1703 } 1704 1705 if (dev->flags & IFF_LOOPBACK || loopback) { 1706 SOCK_DEBUG(sk, "SK %p: Loop back.\n", sk); 1707 /* loop back */ 1708 skb_orphan(skb); 1709 if (ddp->deh_dnode == ATADDR_BCAST) { 1710 struct atalk_addr at_lo; 1711 1712 at_lo.s_node = 0; 1713 at_lo.s_net = 0; 1714 1715 rt = atrtr_find(&at_lo); 1716 if (!rt) { 1717 kfree_skb(skb); 1718 err = -ENETUNREACH; 1719 goto out; 1720 } 1721 dev = rt->dev; 1722 skb->dev = dev; 1723 } 1724 ddp_dl->request(ddp_dl, skb, dev->dev_addr); 1725 } else { 1726 SOCK_DEBUG(sk, "SK %p: send out.\n", sk); 1727 if (rt->flags & RTF_GATEWAY) { 1728 gsat.sat_addr = rt->gateway; 1729 usat = &gsat; 1730 } 1731 1732 /* 1733 * If it fails it is queued/sent above in the aarp queue 1734 */ 1735 aarp_send_ddp(dev, skb, &usat->sat_addr, NULL); 1736 } 1737 SOCK_DEBUG(sk, "SK %p: Done write (%Zd).\n", sk, len); 1738 1739 out: 1740 unlock_kernel(); 1741 return err ? : len; 1742 } 1743 1744 static int atalk_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, 1745 size_t size, int flags) 1746 { 1747 struct sock *sk = sock->sk; 1748 struct sockaddr_at *sat = (struct sockaddr_at *)msg->msg_name; 1749 struct ddpehdr *ddp; 1750 int copied = 0; 1751 int offset = 0; 1752 int err = 0; 1753 struct sk_buff *skb; 1754 1755 lock_kernel(); 1756 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, 1757 flags & MSG_DONTWAIT, &err); 1758 if (!skb) 1759 goto out; 1760 1761 /* FIXME: use skb->cb to be able to use shared skbs */ 1762 ddp = ddp_hdr(skb); 1763 copied = ntohs(ddp->deh_len_hops) & 1023; 1764 1765 if (sk->sk_type != SOCK_RAW) { 1766 offset = sizeof(*ddp); 1767 copied -= offset; 1768 } 1769 1770 if (copied > size) { 1771 copied = size; 1772 msg->msg_flags |= MSG_TRUNC; 1773 } 1774 err = skb_copy_datagram_iovec(skb, offset, msg->msg_iov, copied); 1775 1776 if (!err) { 1777 if (sat) { 1778 sat->sat_family = AF_APPLETALK; 1779 sat->sat_port = ddp->deh_sport; 1780 sat->sat_addr.s_node = ddp->deh_snode; 1781 sat->sat_addr.s_net = ddp->deh_snet; 1782 } 1783 msg->msg_namelen = sizeof(*sat); 1784 } 1785 1786 skb_free_datagram(sk, skb); /* Free the datagram. */ 1787 1788 out: 1789 unlock_kernel(); 1790 return err ? : copied; 1791 } 1792 1793 1794 /* 1795 * AppleTalk ioctl calls. 1796 */ 1797 static int atalk_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 1798 { 1799 int rc = -ENOIOCTLCMD; 1800 struct sock *sk = sock->sk; 1801 void __user *argp = (void __user *)arg; 1802 1803 switch (cmd) { 1804 /* Protocol layer */ 1805 case TIOCOUTQ: { 1806 long amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk); 1807 1808 if (amount < 0) 1809 amount = 0; 1810 rc = put_user(amount, (int __user *)argp); 1811 break; 1812 } 1813 case TIOCINQ: { 1814 /* 1815 * These two are safe on a single CPU system as only 1816 * user tasks fiddle here 1817 */ 1818 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); 1819 long amount = 0; 1820 1821 if (skb) 1822 amount = skb->len - sizeof(struct ddpehdr); 1823 rc = put_user(amount, (int __user *)argp); 1824 break; 1825 } 1826 case SIOCGSTAMP: 1827 rc = sock_get_timestamp(sk, argp); 1828 break; 1829 case SIOCGSTAMPNS: 1830 rc = sock_get_timestampns(sk, argp); 1831 break; 1832 /* Routing */ 1833 case SIOCADDRT: 1834 case SIOCDELRT: 1835 rc = -EPERM; 1836 if (capable(CAP_NET_ADMIN)) 1837 rc = atrtr_ioctl(cmd, argp); 1838 break; 1839 /* Interface */ 1840 case SIOCGIFADDR: 1841 case SIOCSIFADDR: 1842 case SIOCGIFBRDADDR: 1843 case SIOCATALKDIFADDR: 1844 case SIOCDIFADDR: 1845 case SIOCSARP: /* proxy AARP */ 1846 case SIOCDARP: /* proxy AARP */ 1847 rtnl_lock(); 1848 rc = atif_ioctl(cmd, argp); 1849 rtnl_unlock(); 1850 break; 1851 } 1852 1853 return rc; 1854 } 1855 1856 1857 #ifdef CONFIG_COMPAT 1858 static int atalk_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 1859 { 1860 /* 1861 * SIOCATALKDIFADDR is a SIOCPROTOPRIVATE ioctl number, so we 1862 * cannot handle it in common code. The data we access if ifreq 1863 * here is compatible, so we can simply call the native 1864 * handler. 1865 */ 1866 if (cmd == SIOCATALKDIFADDR) 1867 return atalk_ioctl(sock, cmd, (unsigned long)compat_ptr(arg)); 1868 1869 return -ENOIOCTLCMD; 1870 } 1871 #endif 1872 1873 1874 static const struct net_proto_family atalk_family_ops = { 1875 .family = PF_APPLETALK, 1876 .create = atalk_create, 1877 .owner = THIS_MODULE, 1878 }; 1879 1880 static const struct proto_ops atalk_dgram_ops = { 1881 .family = PF_APPLETALK, 1882 .owner = THIS_MODULE, 1883 .release = atalk_release, 1884 .bind = atalk_bind, 1885 .connect = atalk_connect, 1886 .socketpair = sock_no_socketpair, 1887 .accept = sock_no_accept, 1888 .getname = atalk_getname, 1889 .poll = atalk_poll, 1890 .ioctl = atalk_ioctl, 1891 #ifdef CONFIG_COMPAT 1892 .compat_ioctl = atalk_compat_ioctl, 1893 #endif 1894 .listen = sock_no_listen, 1895 .shutdown = sock_no_shutdown, 1896 .setsockopt = sock_no_setsockopt, 1897 .getsockopt = sock_no_getsockopt, 1898 .sendmsg = atalk_sendmsg, 1899 .recvmsg = atalk_recvmsg, 1900 .mmap = sock_no_mmap, 1901 .sendpage = sock_no_sendpage, 1902 }; 1903 1904 static struct notifier_block ddp_notifier = { 1905 .notifier_call = ddp_device_event, 1906 }; 1907 1908 static struct packet_type ltalk_packet_type __read_mostly = { 1909 .type = cpu_to_be16(ETH_P_LOCALTALK), 1910 .func = ltalk_rcv, 1911 }; 1912 1913 static struct packet_type ppptalk_packet_type __read_mostly = { 1914 .type = cpu_to_be16(ETH_P_PPPTALK), 1915 .func = atalk_rcv, 1916 }; 1917 1918 static unsigned char ddp_snap_id[] = { 0x08, 0x00, 0x07, 0x80, 0x9B }; 1919 1920 /* Export symbols for use by drivers when AppleTalk is a module */ 1921 EXPORT_SYMBOL(atrtr_get_dev); 1922 EXPORT_SYMBOL(atalk_find_dev_addr); 1923 1924 static const char atalk_err_snap[] __initconst = 1925 KERN_CRIT "Unable to register DDP with SNAP.\n"; 1926 1927 /* Called by proto.c on kernel start up */ 1928 static int __init atalk_init(void) 1929 { 1930 int rc = proto_register(&ddp_proto, 0); 1931 1932 if (rc != 0) 1933 goto out; 1934 1935 (void)sock_register(&atalk_family_ops); 1936 ddp_dl = register_snap_client(ddp_snap_id, atalk_rcv); 1937 if (!ddp_dl) 1938 printk(atalk_err_snap); 1939 1940 dev_add_pack(<alk_packet_type); 1941 dev_add_pack(&ppptalk_packet_type); 1942 1943 register_netdevice_notifier(&ddp_notifier); 1944 aarp_proto_init(); 1945 atalk_proc_init(); 1946 atalk_register_sysctl(); 1947 out: 1948 return rc; 1949 } 1950 module_init(atalk_init); 1951 1952 /* 1953 * No explicit module reference count manipulation is needed in the 1954 * protocol. Socket layer sets module reference count for us 1955 * and interfaces reference counting is done 1956 * by the network device layer. 1957 * 1958 * Ergo, before the AppleTalk module can be removed, all AppleTalk 1959 * sockets be closed from user space. 1960 */ 1961 static void __exit atalk_exit(void) 1962 { 1963 #ifdef CONFIG_SYSCTL 1964 atalk_unregister_sysctl(); 1965 #endif /* CONFIG_SYSCTL */ 1966 atalk_proc_exit(); 1967 aarp_cleanup_module(); /* General aarp clean-up. */ 1968 unregister_netdevice_notifier(&ddp_notifier); 1969 dev_remove_pack(<alk_packet_type); 1970 dev_remove_pack(&ppptalk_packet_type); 1971 unregister_snap_client(ddp_dl); 1972 sock_unregister(PF_APPLETALK); 1973 proto_unregister(&ddp_proto); 1974 } 1975 module_exit(atalk_exit); 1976 1977 MODULE_LICENSE("GPL"); 1978 MODULE_AUTHOR("Alan Cox <alan@lxorguk.ukuu.org.uk>"); 1979 MODULE_DESCRIPTION("AppleTalk 0.20\n"); 1980 MODULE_ALIAS_NETPROTO(PF_APPLETALK); 1981