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/termios.h> /* For TIOCOUTQ/INQ */ 58 #include <linux/compat.h> 59 #include <linux/slab.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 <linux/highmem.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 97 read_lock_bh(&atalk_sockets_lock); 98 sk_for_each(s, &atalk_sockets) { 99 struct atalk_sock *at = at_sk(s); 100 101 if (to->sat_port != at->src_port) 102 continue; 103 104 if (to->sat_addr.s_net == ATADDR_ANYNET && 105 to->sat_addr.s_node == ATADDR_BCAST) 106 goto found; 107 108 if (to->sat_addr.s_net == at->src_net && 109 (to->sat_addr.s_node == at->src_node || 110 to->sat_addr.s_node == ATADDR_BCAST || 111 to->sat_addr.s_node == ATADDR_ANYNODE)) 112 goto found; 113 114 /* XXXX.0 -- we got a request for this router. make sure 115 * that the node is appropriately set. */ 116 if (to->sat_addr.s_node == ATADDR_ANYNODE && 117 to->sat_addr.s_net != ATADDR_ANYNET && 118 atif->address.s_node == at->src_node) { 119 to->sat_addr.s_node = atif->address.s_node; 120 goto found; 121 } 122 } 123 s = NULL; 124 found: 125 read_unlock_bh(&atalk_sockets_lock); 126 return s; 127 } 128 129 /** 130 * atalk_find_or_insert_socket - Try to find a socket matching ADDR 131 * @sk: socket to insert in the list if it is not there already 132 * @sat: address to search for 133 * 134 * Try to find a socket matching ADDR in the socket list, if found then return 135 * it. If not, insert SK into the socket list. 136 * 137 * This entire operation must execute atomically. 138 */ 139 static struct sock *atalk_find_or_insert_socket(struct sock *sk, 140 struct sockaddr_at *sat) 141 { 142 struct sock *s; 143 struct atalk_sock *at; 144 145 write_lock_bh(&atalk_sockets_lock); 146 sk_for_each(s, &atalk_sockets) { 147 at = at_sk(s); 148 149 if (at->src_net == sat->sat_addr.s_net && 150 at->src_node == sat->sat_addr.s_node && 151 at->src_port == sat->sat_port) 152 goto found; 153 } 154 s = NULL; 155 __atalk_insert_socket(sk); /* Wheee, it's free, assign and insert. */ 156 found: 157 write_unlock_bh(&atalk_sockets_lock); 158 return s; 159 } 160 161 static void atalk_destroy_timer(struct timer_list *t) 162 { 163 struct sock *sk = from_timer(sk, t, sk_timer); 164 165 if (sk_has_allocations(sk)) { 166 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME; 167 add_timer(&sk->sk_timer); 168 } else 169 sock_put(sk); 170 } 171 172 static inline void atalk_destroy_socket(struct sock *sk) 173 { 174 atalk_remove_socket(sk); 175 skb_queue_purge(&sk->sk_receive_queue); 176 177 if (sk_has_allocations(sk)) { 178 timer_setup(&sk->sk_timer, atalk_destroy_timer, 0); 179 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME; 180 add_timer(&sk->sk_timer); 181 } else 182 sock_put(sk); 183 } 184 185 /**************************************************************************\ 186 * * 187 * Routing tables for the AppleTalk socket layer. * 188 * * 189 \**************************************************************************/ 190 191 /* Anti-deadlock ordering is atalk_routes_lock --> iface_lock -DaveM */ 192 struct atalk_route *atalk_routes; 193 DEFINE_RWLOCK(atalk_routes_lock); 194 195 struct atalk_iface *atalk_interfaces; 196 DEFINE_RWLOCK(atalk_interfaces_lock); 197 198 /* For probing devices or in a routerless network */ 199 struct atalk_route atrtr_default; 200 201 /* AppleTalk interface control */ 202 /* 203 * Drop a device. Doesn't drop any of its routes - that is the caller's 204 * problem. Called when we down the interface or delete the address. 205 */ 206 static void atif_drop_device(struct net_device *dev) 207 { 208 struct atalk_iface **iface = &atalk_interfaces; 209 struct atalk_iface *tmp; 210 211 write_lock_bh(&atalk_interfaces_lock); 212 while ((tmp = *iface) != NULL) { 213 if (tmp->dev == dev) { 214 *iface = tmp->next; 215 dev_put(dev); 216 kfree(tmp); 217 dev->atalk_ptr = NULL; 218 } else 219 iface = &tmp->next; 220 } 221 write_unlock_bh(&atalk_interfaces_lock); 222 } 223 224 static struct atalk_iface *atif_add_device(struct net_device *dev, 225 struct atalk_addr *sa) 226 { 227 struct atalk_iface *iface = kzalloc(sizeof(*iface), GFP_KERNEL); 228 229 if (!iface) 230 goto out; 231 232 dev_hold(dev); 233 iface->dev = dev; 234 dev->atalk_ptr = iface; 235 iface->address = *sa; 236 iface->status = 0; 237 238 write_lock_bh(&atalk_interfaces_lock); 239 iface->next = atalk_interfaces; 240 atalk_interfaces = iface; 241 write_unlock_bh(&atalk_interfaces_lock); 242 out: 243 return iface; 244 } 245 246 /* Perform phase 2 AARP probing on our tentative address */ 247 static int atif_probe_device(struct atalk_iface *atif) 248 { 249 int netrange = ntohs(atif->nets.nr_lastnet) - 250 ntohs(atif->nets.nr_firstnet) + 1; 251 int probe_net = ntohs(atif->address.s_net); 252 int probe_node = atif->address.s_node; 253 int netct, nodect; 254 255 /* Offset the network we start probing with */ 256 if (probe_net == ATADDR_ANYNET) { 257 probe_net = ntohs(atif->nets.nr_firstnet); 258 if (netrange) 259 probe_net += jiffies % netrange; 260 } 261 if (probe_node == ATADDR_ANYNODE) 262 probe_node = jiffies & 0xFF; 263 264 /* Scan the networks */ 265 atif->status |= ATIF_PROBE; 266 for (netct = 0; netct <= netrange; netct++) { 267 /* Sweep the available nodes from a given start */ 268 atif->address.s_net = htons(probe_net); 269 for (nodect = 0; nodect < 256; nodect++) { 270 atif->address.s_node = (nodect + probe_node) & 0xFF; 271 if (atif->address.s_node > 0 && 272 atif->address.s_node < 254) { 273 /* Probe a proposed address */ 274 aarp_probe_network(atif); 275 276 if (!(atif->status & ATIF_PROBE_FAIL)) { 277 atif->status &= ~ATIF_PROBE; 278 return 0; 279 } 280 } 281 atif->status &= ~ATIF_PROBE_FAIL; 282 } 283 probe_net++; 284 if (probe_net > ntohs(atif->nets.nr_lastnet)) 285 probe_net = ntohs(atif->nets.nr_firstnet); 286 } 287 atif->status &= ~ATIF_PROBE; 288 289 return -EADDRINUSE; /* Network is full... */ 290 } 291 292 293 /* Perform AARP probing for a proxy address */ 294 static int atif_proxy_probe_device(struct atalk_iface *atif, 295 struct atalk_addr *proxy_addr) 296 { 297 int netrange = ntohs(atif->nets.nr_lastnet) - 298 ntohs(atif->nets.nr_firstnet) + 1; 299 /* we probe the interface's network */ 300 int probe_net = ntohs(atif->address.s_net); 301 int probe_node = ATADDR_ANYNODE; /* we'll take anything */ 302 int netct, nodect; 303 304 /* Offset the network we start probing with */ 305 if (probe_net == ATADDR_ANYNET) { 306 probe_net = ntohs(atif->nets.nr_firstnet); 307 if (netrange) 308 probe_net += jiffies % netrange; 309 } 310 311 if (probe_node == ATADDR_ANYNODE) 312 probe_node = jiffies & 0xFF; 313 314 /* Scan the networks */ 315 for (netct = 0; netct <= netrange; netct++) { 316 /* Sweep the available nodes from a given start */ 317 proxy_addr->s_net = htons(probe_net); 318 for (nodect = 0; nodect < 256; nodect++) { 319 proxy_addr->s_node = (nodect + probe_node) & 0xFF; 320 if (proxy_addr->s_node > 0 && 321 proxy_addr->s_node < 254) { 322 /* Tell AARP to probe a proposed address */ 323 int ret = aarp_proxy_probe_network(atif, 324 proxy_addr); 325 326 if (ret != -EADDRINUSE) 327 return ret; 328 } 329 } 330 probe_net++; 331 if (probe_net > ntohs(atif->nets.nr_lastnet)) 332 probe_net = ntohs(atif->nets.nr_firstnet); 333 } 334 335 return -EADDRINUSE; /* Network is full... */ 336 } 337 338 339 struct atalk_addr *atalk_find_dev_addr(struct net_device *dev) 340 { 341 struct atalk_iface *iface = dev->atalk_ptr; 342 return iface ? &iface->address : NULL; 343 } 344 345 static struct atalk_addr *atalk_find_primary(void) 346 { 347 struct atalk_iface *fiface = NULL; 348 struct atalk_addr *retval; 349 struct atalk_iface *iface; 350 351 /* 352 * Return a point-to-point interface only if 353 * there is no non-ptp interface available. 354 */ 355 read_lock_bh(&atalk_interfaces_lock); 356 for (iface = atalk_interfaces; iface; iface = iface->next) { 357 if (!fiface && !(iface->dev->flags & IFF_LOOPBACK)) 358 fiface = iface; 359 if (!(iface->dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) { 360 retval = &iface->address; 361 goto out; 362 } 363 } 364 365 if (fiface) 366 retval = &fiface->address; 367 else if (atalk_interfaces) 368 retval = &atalk_interfaces->address; 369 else 370 retval = NULL; 371 out: 372 read_unlock_bh(&atalk_interfaces_lock); 373 return retval; 374 } 375 376 /* 377 * Find a match for 'any network' - ie any of our interfaces with that 378 * node number will do just nicely. 379 */ 380 static struct atalk_iface *atalk_find_anynet(int node, struct net_device *dev) 381 { 382 struct atalk_iface *iface = dev->atalk_ptr; 383 384 if (!iface || iface->status & ATIF_PROBE) 385 goto out_err; 386 387 if (node != ATADDR_BCAST && 388 iface->address.s_node != node && 389 node != ATADDR_ANYNODE) 390 goto out_err; 391 out: 392 return iface; 393 out_err: 394 iface = NULL; 395 goto out; 396 } 397 398 /* Find a match for a specific network:node pair */ 399 static struct atalk_iface *atalk_find_interface(__be16 net, int node) 400 { 401 struct atalk_iface *iface; 402 403 read_lock_bh(&atalk_interfaces_lock); 404 for (iface = atalk_interfaces; iface; iface = iface->next) { 405 if ((node == ATADDR_BCAST || 406 node == ATADDR_ANYNODE || 407 iface->address.s_node == node) && 408 iface->address.s_net == net && 409 !(iface->status & ATIF_PROBE)) 410 break; 411 412 /* XXXX.0 -- net.0 returns the iface associated with net */ 413 if (node == ATADDR_ANYNODE && net != ATADDR_ANYNET && 414 ntohs(iface->nets.nr_firstnet) <= ntohs(net) && 415 ntohs(net) <= ntohs(iface->nets.nr_lastnet)) 416 break; 417 } 418 read_unlock_bh(&atalk_interfaces_lock); 419 return iface; 420 } 421 422 423 /* 424 * Find a route for an AppleTalk packet. This ought to get cached in 425 * the socket (later on...). We know about host routes and the fact 426 * that a route must be direct to broadcast. 427 */ 428 static struct atalk_route *atrtr_find(struct atalk_addr *target) 429 { 430 /* 431 * we must search through all routes unless we find a 432 * host route, because some host routes might overlap 433 * network routes 434 */ 435 struct atalk_route *net_route = NULL; 436 struct atalk_route *r; 437 438 read_lock_bh(&atalk_routes_lock); 439 for (r = atalk_routes; r; r = r->next) { 440 if (!(r->flags & RTF_UP)) 441 continue; 442 443 if (r->target.s_net == target->s_net) { 444 if (r->flags & RTF_HOST) { 445 /* 446 * if this host route is for the target, 447 * the we're done 448 */ 449 if (r->target.s_node == target->s_node) 450 goto out; 451 } else 452 /* 453 * this route will work if there isn't a 454 * direct host route, so cache it 455 */ 456 net_route = r; 457 } 458 } 459 460 /* 461 * if we found a network route but not a direct host 462 * route, then return it 463 */ 464 if (net_route) 465 r = net_route; 466 else if (atrtr_default.dev) 467 r = &atrtr_default; 468 else /* No route can be found */ 469 r = NULL; 470 out: 471 read_unlock_bh(&atalk_routes_lock); 472 return r; 473 } 474 475 476 /* 477 * Given an AppleTalk network, find the device to use. This can be 478 * a simple lookup. 479 */ 480 struct net_device *atrtr_get_dev(struct atalk_addr *sa) 481 { 482 struct atalk_route *atr = atrtr_find(sa); 483 return atr ? atr->dev : NULL; 484 } 485 486 /* Set up a default router */ 487 static void atrtr_set_default(struct net_device *dev) 488 { 489 atrtr_default.dev = dev; 490 atrtr_default.flags = RTF_UP; 491 atrtr_default.gateway.s_net = htons(0); 492 atrtr_default.gateway.s_node = 0; 493 } 494 495 /* 496 * Add a router. Basically make sure it looks valid and stuff the 497 * entry in the list. While it uses netranges we always set them to one 498 * entry to work like netatalk. 499 */ 500 static int atrtr_create(struct rtentry *r, struct net_device *devhint) 501 { 502 struct sockaddr_at *ta = (struct sockaddr_at *)&r->rt_dst; 503 struct sockaddr_at *ga = (struct sockaddr_at *)&r->rt_gateway; 504 struct atalk_route *rt; 505 struct atalk_iface *iface, *riface; 506 int retval = -EINVAL; 507 508 /* 509 * Fixme: Raise/Lower a routing change semaphore for these 510 * operations. 511 */ 512 513 /* Validate the request */ 514 if (ta->sat_family != AF_APPLETALK || 515 (!devhint && ga->sat_family != AF_APPLETALK)) 516 goto out; 517 518 /* Now walk the routing table and make our decisions */ 519 write_lock_bh(&atalk_routes_lock); 520 for (rt = atalk_routes; rt; rt = rt->next) { 521 if (r->rt_flags != rt->flags) 522 continue; 523 524 if (ta->sat_addr.s_net == rt->target.s_net) { 525 if (!(rt->flags & RTF_HOST)) 526 break; 527 if (ta->sat_addr.s_node == rt->target.s_node) 528 break; 529 } 530 } 531 532 if (!devhint) { 533 riface = NULL; 534 535 read_lock_bh(&atalk_interfaces_lock); 536 for (iface = atalk_interfaces; iface; iface = iface->next) { 537 if (!riface && 538 ntohs(ga->sat_addr.s_net) >= 539 ntohs(iface->nets.nr_firstnet) && 540 ntohs(ga->sat_addr.s_net) <= 541 ntohs(iface->nets.nr_lastnet)) 542 riface = iface; 543 544 if (ga->sat_addr.s_net == iface->address.s_net && 545 ga->sat_addr.s_node == iface->address.s_node) 546 riface = iface; 547 } 548 read_unlock_bh(&atalk_interfaces_lock); 549 550 retval = -ENETUNREACH; 551 if (!riface) 552 goto out_unlock; 553 554 devhint = riface->dev; 555 } 556 557 if (!rt) { 558 rt = kzalloc(sizeof(*rt), GFP_ATOMIC); 559 560 retval = -ENOBUFS; 561 if (!rt) 562 goto out_unlock; 563 564 rt->next = atalk_routes; 565 atalk_routes = rt; 566 } 567 568 /* Fill in the routing entry */ 569 rt->target = ta->sat_addr; 570 dev_hold(devhint); 571 rt->dev = devhint; 572 rt->flags = r->rt_flags; 573 rt->gateway = ga->sat_addr; 574 575 retval = 0; 576 out_unlock: 577 write_unlock_bh(&atalk_routes_lock); 578 out: 579 return retval; 580 } 581 582 /* Delete a route. Find it and discard it */ 583 static int atrtr_delete(struct atalk_addr *addr) 584 { 585 struct atalk_route **r = &atalk_routes; 586 int retval = 0; 587 struct atalk_route *tmp; 588 589 write_lock_bh(&atalk_routes_lock); 590 while ((tmp = *r) != NULL) { 591 if (tmp->target.s_net == addr->s_net && 592 (!(tmp->flags&RTF_GATEWAY) || 593 tmp->target.s_node == addr->s_node)) { 594 *r = tmp->next; 595 dev_put(tmp->dev); 596 kfree(tmp); 597 goto out; 598 } 599 r = &tmp->next; 600 } 601 retval = -ENOENT; 602 out: 603 write_unlock_bh(&atalk_routes_lock); 604 return retval; 605 } 606 607 /* 608 * Called when a device is downed. Just throw away any routes 609 * via it. 610 */ 611 static void atrtr_device_down(struct net_device *dev) 612 { 613 struct atalk_route **r = &atalk_routes; 614 struct atalk_route *tmp; 615 616 write_lock_bh(&atalk_routes_lock); 617 while ((tmp = *r) != NULL) { 618 if (tmp->dev == dev) { 619 *r = tmp->next; 620 dev_put(dev); 621 kfree(tmp); 622 } else 623 r = &tmp->next; 624 } 625 write_unlock_bh(&atalk_routes_lock); 626 627 if (atrtr_default.dev == dev) 628 atrtr_set_default(NULL); 629 } 630 631 /* Actually down the interface */ 632 static inline void atalk_dev_down(struct net_device *dev) 633 { 634 atrtr_device_down(dev); /* Remove all routes for the device */ 635 aarp_device_down(dev); /* Remove AARP entries for the device */ 636 atif_drop_device(dev); /* Remove the device */ 637 } 638 639 /* 640 * A device event has occurred. Watch for devices going down and 641 * delete our use of them (iface and route). 642 */ 643 static int ddp_device_event(struct notifier_block *this, unsigned long event, 644 void *ptr) 645 { 646 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 647 648 if (!net_eq(dev_net(dev), &init_net)) 649 return NOTIFY_DONE; 650 651 if (event == NETDEV_DOWN) 652 /* Discard any use of this */ 653 atalk_dev_down(dev); 654 655 return NOTIFY_DONE; 656 } 657 658 /* ioctl calls. Shouldn't even need touching */ 659 /* Device configuration ioctl calls */ 660 static int atif_ioctl(int cmd, void __user *arg) 661 { 662 static char aarp_mcast[6] = { 0x09, 0x00, 0x00, 0xFF, 0xFF, 0xFF }; 663 struct ifreq atreq; 664 struct atalk_netrange *nr; 665 struct sockaddr_at *sa; 666 struct net_device *dev; 667 struct atalk_iface *atif; 668 int ct; 669 int limit; 670 struct rtentry rtdef; 671 int add_route; 672 673 if (copy_from_user(&atreq, arg, sizeof(atreq))) 674 return -EFAULT; 675 676 dev = __dev_get_by_name(&init_net, atreq.ifr_name); 677 if (!dev) 678 return -ENODEV; 679 680 sa = (struct sockaddr_at *)&atreq.ifr_addr; 681 atif = atalk_find_dev(dev); 682 683 switch (cmd) { 684 case SIOCSIFADDR: 685 if (!capable(CAP_NET_ADMIN)) 686 return -EPERM; 687 if (sa->sat_family != AF_APPLETALK) 688 return -EINVAL; 689 if (dev->type != ARPHRD_ETHER && 690 dev->type != ARPHRD_LOOPBACK && 691 dev->type != ARPHRD_LOCALTLK && 692 dev->type != ARPHRD_PPP) 693 return -EPROTONOSUPPORT; 694 695 nr = (struct atalk_netrange *)&sa->sat_zero[0]; 696 add_route = 1; 697 698 /* 699 * if this is a point-to-point iface, and we already 700 * have an iface for this AppleTalk address, then we 701 * should not add a route 702 */ 703 if ((dev->flags & IFF_POINTOPOINT) && 704 atalk_find_interface(sa->sat_addr.s_net, 705 sa->sat_addr.s_node)) { 706 printk(KERN_DEBUG "AppleTalk: point-to-point " 707 "interface added with " 708 "existing address\n"); 709 add_route = 0; 710 } 711 712 /* 713 * Phase 1 is fine on LocalTalk but we don't do 714 * EtherTalk phase 1. Anyone wanting to add it go ahead. 715 */ 716 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2) 717 return -EPROTONOSUPPORT; 718 if (sa->sat_addr.s_node == ATADDR_BCAST || 719 sa->sat_addr.s_node == 254) 720 return -EINVAL; 721 if (atif) { 722 /* Already setting address */ 723 if (atif->status & ATIF_PROBE) 724 return -EBUSY; 725 726 atif->address.s_net = sa->sat_addr.s_net; 727 atif->address.s_node = sa->sat_addr.s_node; 728 atrtr_device_down(dev); /* Flush old routes */ 729 } else { 730 atif = atif_add_device(dev, &sa->sat_addr); 731 if (!atif) 732 return -ENOMEM; 733 } 734 atif->nets = *nr; 735 736 /* 737 * Check if the chosen address is used. If so we 738 * error and atalkd will try another. 739 */ 740 741 if (!(dev->flags & IFF_LOOPBACK) && 742 !(dev->flags & IFF_POINTOPOINT) && 743 atif_probe_device(atif) < 0) { 744 atif_drop_device(dev); 745 return -EADDRINUSE; 746 } 747 748 /* Hey it worked - add the direct routes */ 749 sa = (struct sockaddr_at *)&rtdef.rt_gateway; 750 sa->sat_family = AF_APPLETALK; 751 sa->sat_addr.s_net = atif->address.s_net; 752 sa->sat_addr.s_node = atif->address.s_node; 753 sa = (struct sockaddr_at *)&rtdef.rt_dst; 754 rtdef.rt_flags = RTF_UP; 755 sa->sat_family = AF_APPLETALK; 756 sa->sat_addr.s_node = ATADDR_ANYNODE; 757 if (dev->flags & IFF_LOOPBACK || 758 dev->flags & IFF_POINTOPOINT) 759 rtdef.rt_flags |= RTF_HOST; 760 761 /* Routerless initial state */ 762 if (nr->nr_firstnet == htons(0) && 763 nr->nr_lastnet == htons(0xFFFE)) { 764 sa->sat_addr.s_net = atif->address.s_net; 765 atrtr_create(&rtdef, dev); 766 atrtr_set_default(dev); 767 } else { 768 limit = ntohs(nr->nr_lastnet); 769 if (limit - ntohs(nr->nr_firstnet) > 4096) { 770 printk(KERN_WARNING "Too many routes/" 771 "iface.\n"); 772 return -EINVAL; 773 } 774 if (add_route) 775 for (ct = ntohs(nr->nr_firstnet); 776 ct <= limit; ct++) { 777 sa->sat_addr.s_net = htons(ct); 778 atrtr_create(&rtdef, dev); 779 } 780 } 781 dev_mc_add_global(dev, aarp_mcast); 782 return 0; 783 784 case SIOCGIFADDR: 785 if (!atif) 786 return -EADDRNOTAVAIL; 787 788 sa->sat_family = AF_APPLETALK; 789 sa->sat_addr = atif->address; 790 break; 791 792 case SIOCGIFBRDADDR: 793 if (!atif) 794 return -EADDRNOTAVAIL; 795 796 sa->sat_family = AF_APPLETALK; 797 sa->sat_addr.s_net = atif->address.s_net; 798 sa->sat_addr.s_node = ATADDR_BCAST; 799 break; 800 801 case SIOCATALKDIFADDR: 802 case SIOCDIFADDR: 803 if (!capable(CAP_NET_ADMIN)) 804 return -EPERM; 805 if (sa->sat_family != AF_APPLETALK) 806 return -EINVAL; 807 atalk_dev_down(dev); 808 break; 809 810 case SIOCSARP: 811 if (!capable(CAP_NET_ADMIN)) 812 return -EPERM; 813 if (sa->sat_family != AF_APPLETALK) 814 return -EINVAL; 815 /* 816 * for now, we only support proxy AARP on ELAP; 817 * we should be able to do it for LocalTalk, too. 818 */ 819 if (dev->type != ARPHRD_ETHER) 820 return -EPROTONOSUPPORT; 821 822 /* 823 * atif points to the current interface on this network; 824 * we aren't concerned about its current status (at 825 * least for now), but it has all the settings about 826 * the network we're going to probe. Consequently, it 827 * must exist. 828 */ 829 if (!atif) 830 return -EADDRNOTAVAIL; 831 832 nr = (struct atalk_netrange *)&(atif->nets); 833 /* 834 * Phase 1 is fine on Localtalk but we don't do 835 * Ethertalk phase 1. Anyone wanting to add it go ahead. 836 */ 837 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2) 838 return -EPROTONOSUPPORT; 839 840 if (sa->sat_addr.s_node == ATADDR_BCAST || 841 sa->sat_addr.s_node == 254) 842 return -EINVAL; 843 844 /* 845 * Check if the chosen address is used. If so we 846 * error and ATCP will try another. 847 */ 848 if (atif_proxy_probe_device(atif, &(sa->sat_addr)) < 0) 849 return -EADDRINUSE; 850 851 /* 852 * We now have an address on the local network, and 853 * the AARP code will defend it for us until we take it 854 * down. We don't set up any routes right now, because 855 * ATCP will install them manually via SIOCADDRT. 856 */ 857 break; 858 859 case SIOCDARP: 860 if (!capable(CAP_NET_ADMIN)) 861 return -EPERM; 862 if (sa->sat_family != AF_APPLETALK) 863 return -EINVAL; 864 if (!atif) 865 return -EADDRNOTAVAIL; 866 867 /* give to aarp module to remove proxy entry */ 868 aarp_proxy_remove(atif->dev, &(sa->sat_addr)); 869 return 0; 870 } 871 872 return copy_to_user(arg, &atreq, sizeof(atreq)) ? -EFAULT : 0; 873 } 874 875 /* Routing ioctl() calls */ 876 static int atrtr_ioctl(unsigned int cmd, void __user *arg) 877 { 878 struct rtentry rt; 879 880 if (copy_from_user(&rt, arg, sizeof(rt))) 881 return -EFAULT; 882 883 switch (cmd) { 884 case SIOCDELRT: 885 if (rt.rt_dst.sa_family != AF_APPLETALK) 886 return -EINVAL; 887 return atrtr_delete(&((struct sockaddr_at *) 888 &rt.rt_dst)->sat_addr); 889 890 case SIOCADDRT: { 891 struct net_device *dev = NULL; 892 if (rt.rt_dev) { 893 char name[IFNAMSIZ]; 894 if (copy_from_user(name, rt.rt_dev, IFNAMSIZ-1)) 895 return -EFAULT; 896 name[IFNAMSIZ-1] = '\0'; 897 dev = __dev_get_by_name(&init_net, name); 898 if (!dev) 899 return -ENODEV; 900 } 901 return atrtr_create(&rt, dev); 902 } 903 } 904 return -EINVAL; 905 } 906 907 /**************************************************************************\ 908 * * 909 * Handling for system calls applied via the various interfaces to an * 910 * AppleTalk socket object. * 911 * * 912 \**************************************************************************/ 913 914 /* 915 * Checksum: This is 'optional'. It's quite likely also a good 916 * candidate for assembler hackery 8) 917 */ 918 static unsigned long atalk_sum_partial(const unsigned char *data, 919 int len, unsigned long sum) 920 { 921 /* This ought to be unwrapped neatly. I'll trust gcc for now */ 922 while (len--) { 923 sum += *data++; 924 sum = rol16(sum, 1); 925 } 926 return sum; 927 } 928 929 /* Checksum skb data -- similar to skb_checksum */ 930 static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, 931 int len, unsigned long sum) 932 { 933 int start = skb_headlen(skb); 934 struct sk_buff *frag_iter; 935 int i, copy; 936 937 /* checksum stuff in header space */ 938 if ((copy = start - offset) > 0) { 939 if (copy > len) 940 copy = len; 941 sum = atalk_sum_partial(skb->data + offset, copy, sum); 942 if ((len -= copy) == 0) 943 return sum; 944 945 offset += copy; 946 } 947 948 /* checksum stuff in frags */ 949 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 950 int end; 951 const skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 952 WARN_ON(start > offset + len); 953 954 end = start + skb_frag_size(frag); 955 if ((copy = end - offset) > 0) { 956 u8 *vaddr; 957 958 if (copy > len) 959 copy = len; 960 vaddr = kmap_atomic(skb_frag_page(frag)); 961 sum = atalk_sum_partial(vaddr + frag->page_offset + 962 offset - start, copy, sum); 963 kunmap_atomic(vaddr); 964 965 if (!(len -= copy)) 966 return sum; 967 offset += copy; 968 } 969 start = end; 970 } 971 972 skb_walk_frags(skb, frag_iter) { 973 int end; 974 975 WARN_ON(start > offset + len); 976 977 end = start + frag_iter->len; 978 if ((copy = end - offset) > 0) { 979 if (copy > len) 980 copy = len; 981 sum = atalk_sum_skb(frag_iter, offset - start, 982 copy, sum); 983 if ((len -= copy) == 0) 984 return sum; 985 offset += copy; 986 } 987 start = end; 988 } 989 990 BUG_ON(len > 0); 991 992 return sum; 993 } 994 995 static __be16 atalk_checksum(const struct sk_buff *skb, int len) 996 { 997 unsigned long sum; 998 999 /* skip header 4 bytes */ 1000 sum = atalk_sum_skb(skb, 4, len-4, 0); 1001 1002 /* Use 0xFFFF for 0. 0 itself means none */ 1003 return sum ? htons((unsigned short)sum) : htons(0xFFFF); 1004 } 1005 1006 static struct proto ddp_proto = { 1007 .name = "DDP", 1008 .owner = THIS_MODULE, 1009 .obj_size = sizeof(struct atalk_sock), 1010 }; 1011 1012 /* 1013 * Create a socket. Initialise the socket, blank the addresses 1014 * set the state. 1015 */ 1016 static int atalk_create(struct net *net, struct socket *sock, int protocol, 1017 int kern) 1018 { 1019 struct sock *sk; 1020 int rc = -ESOCKTNOSUPPORT; 1021 1022 if (!net_eq(net, &init_net)) 1023 return -EAFNOSUPPORT; 1024 1025 /* 1026 * We permit SOCK_DGRAM and RAW is an extension. It is trivial to do 1027 * and gives you the full ELAP frame. Should be handy for CAP 8) 1028 */ 1029 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) 1030 goto out; 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 case SIOCGSTAMP: 1810 rc = sock_get_timestamp(sk, argp); 1811 break; 1812 case SIOCGSTAMPNS: 1813 rc = sock_get_timestampns(sk, argp); 1814 break; 1815 /* Routing */ 1816 case SIOCADDRT: 1817 case SIOCDELRT: 1818 rc = -EPERM; 1819 if (capable(CAP_NET_ADMIN)) 1820 rc = atrtr_ioctl(cmd, argp); 1821 break; 1822 /* Interface */ 1823 case SIOCGIFADDR: 1824 case SIOCSIFADDR: 1825 case SIOCGIFBRDADDR: 1826 case SIOCATALKDIFADDR: 1827 case SIOCDIFADDR: 1828 case SIOCSARP: /* proxy AARP */ 1829 case SIOCDARP: /* proxy AARP */ 1830 rtnl_lock(); 1831 rc = atif_ioctl(cmd, argp); 1832 rtnl_unlock(); 1833 break; 1834 } 1835 1836 return rc; 1837 } 1838 1839 1840 #ifdef CONFIG_COMPAT 1841 static int atalk_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 1842 { 1843 /* 1844 * SIOCATALKDIFADDR is a SIOCPROTOPRIVATE ioctl number, so we 1845 * cannot handle it in common code. The data we access if ifreq 1846 * here is compatible, so we can simply call the native 1847 * handler. 1848 */ 1849 if (cmd == SIOCATALKDIFADDR) 1850 return atalk_ioctl(sock, cmd, (unsigned long)compat_ptr(arg)); 1851 1852 return -ENOIOCTLCMD; 1853 } 1854 #endif 1855 1856 1857 static const struct net_proto_family atalk_family_ops = { 1858 .family = PF_APPLETALK, 1859 .create = atalk_create, 1860 .owner = THIS_MODULE, 1861 }; 1862 1863 static const struct proto_ops atalk_dgram_ops = { 1864 .family = PF_APPLETALK, 1865 .owner = THIS_MODULE, 1866 .release = atalk_release, 1867 .bind = atalk_bind, 1868 .connect = atalk_connect, 1869 .socketpair = sock_no_socketpair, 1870 .accept = sock_no_accept, 1871 .getname = atalk_getname, 1872 .poll = datagram_poll, 1873 .ioctl = atalk_ioctl, 1874 #ifdef CONFIG_COMPAT 1875 .compat_ioctl = atalk_compat_ioctl, 1876 #endif 1877 .listen = sock_no_listen, 1878 .shutdown = sock_no_shutdown, 1879 .setsockopt = sock_no_setsockopt, 1880 .getsockopt = sock_no_getsockopt, 1881 .sendmsg = atalk_sendmsg, 1882 .recvmsg = atalk_recvmsg, 1883 .mmap = sock_no_mmap, 1884 .sendpage = sock_no_sendpage, 1885 }; 1886 1887 static struct notifier_block ddp_notifier = { 1888 .notifier_call = ddp_device_event, 1889 }; 1890 1891 static struct packet_type ltalk_packet_type __read_mostly = { 1892 .type = cpu_to_be16(ETH_P_LOCALTALK), 1893 .func = ltalk_rcv, 1894 }; 1895 1896 static struct packet_type ppptalk_packet_type __read_mostly = { 1897 .type = cpu_to_be16(ETH_P_PPPTALK), 1898 .func = atalk_rcv, 1899 }; 1900 1901 static unsigned char ddp_snap_id[] = { 0x08, 0x00, 0x07, 0x80, 0x9B }; 1902 1903 /* Export symbols for use by drivers when AppleTalk is a module */ 1904 EXPORT_SYMBOL(atrtr_get_dev); 1905 EXPORT_SYMBOL(atalk_find_dev_addr); 1906 1907 static const char atalk_err_snap[] __initconst = 1908 KERN_CRIT "Unable to register DDP with SNAP.\n"; 1909 1910 /* Called by proto.c on kernel start up */ 1911 static int __init atalk_init(void) 1912 { 1913 int rc = proto_register(&ddp_proto, 0); 1914 1915 if (rc != 0) 1916 goto out; 1917 1918 (void)sock_register(&atalk_family_ops); 1919 ddp_dl = register_snap_client(ddp_snap_id, atalk_rcv); 1920 if (!ddp_dl) 1921 printk(atalk_err_snap); 1922 1923 dev_add_pack(<alk_packet_type); 1924 dev_add_pack(&ppptalk_packet_type); 1925 1926 register_netdevice_notifier(&ddp_notifier); 1927 aarp_proto_init(); 1928 atalk_proc_init(); 1929 atalk_register_sysctl(); 1930 out: 1931 return rc; 1932 } 1933 module_init(atalk_init); 1934 1935 /* 1936 * No explicit module reference count manipulation is needed in the 1937 * protocol. Socket layer sets module reference count for us 1938 * and interfaces reference counting is done 1939 * by the network device layer. 1940 * 1941 * Ergo, before the AppleTalk module can be removed, all AppleTalk 1942 * sockets be closed from user space. 1943 */ 1944 static void __exit atalk_exit(void) 1945 { 1946 #ifdef CONFIG_SYSCTL 1947 atalk_unregister_sysctl(); 1948 #endif /* CONFIG_SYSCTL */ 1949 atalk_proc_exit(); 1950 aarp_cleanup_module(); /* General aarp clean-up. */ 1951 unregister_netdevice_notifier(&ddp_notifier); 1952 dev_remove_pack(<alk_packet_type); 1953 dev_remove_pack(&ppptalk_packet_type); 1954 unregister_snap_client(ddp_dl); 1955 sock_unregister(PF_APPLETALK); 1956 proto_unregister(&ddp_proto); 1957 } 1958 module_exit(atalk_exit); 1959 1960 MODULE_LICENSE("GPL"); 1961 MODULE_AUTHOR("Alan Cox <alan@lxorguk.ukuu.org.uk>"); 1962 MODULE_DESCRIPTION("AppleTalk 0.20\n"); 1963 MODULE_ALIAS_NETPROTO(PF_APPLETALK); 1964