1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * DDP: An implementation of the AppleTalk DDP protocol for 4 * Ethernet 'ELAP'. 5 * 6 * Alan Cox <alan@lxorguk.ukuu.org.uk> 7 * 8 * With more than a little assistance from 9 * 10 * Wesley Craig <netatalk@umich.edu> 11 * 12 * Fixes: 13 * Neil Horman : Added missing device ioctls 14 * Michael Callahan : Made routing work 15 * Wesley Craig : Fix probing to listen to a 16 * passed node id. 17 * Alan Cox : Added send/recvmsg support 18 * Alan Cox : Moved at. to protinfo in 19 * socket. 20 * Alan Cox : Added firewall hooks. 21 * Alan Cox : Supports new ARPHRD_LOOPBACK 22 * Christer Weinigel : Routing and /proc fixes. 23 * Bradford Johnson : LocalTalk. 24 * Tom Dyas : Module support. 25 * Alan Cox : Hooks for PPP (based on the 26 * LocalTalk hook). 27 * Alan Cox : Posix bits 28 * Alan Cox/Mike Freeman : Possible fix to NBP problems 29 * Bradford Johnson : IP-over-DDP (experimental) 30 * Jay Schulist : Moved IP-over-DDP to its own 31 * driver file. (ipddp.c & ipddp.h) 32 * Jay Schulist : Made work as module with 33 * AppleTalk drivers, cleaned it. 34 * Rob Newberry : Added proxy AARP and AARP 35 * procfs, moved probing to AARP 36 * module. 37 * Adrian Sun/ 38 * Michael Zuelsdorff : fix for net.0 packets. don't 39 * allow illegal ether/tokentalk 40 * port assignment. we lose a 41 * valid localtalk port as a 42 * result. 43 * Arnaldo C. de Melo : Cleanup, in preparation for 44 * shared skb support 8) 45 * Arnaldo C. de Melo : Move proc stuff to atalk_proc.c, 46 * use seq_file 47 */ 48 49 #include <linux/capability.h> 50 #include <linux/module.h> 51 #include <linux/if_arp.h> 52 #include <linux/termios.h> /* For TIOCOUTQ/INQ */ 53 #include <linux/compat.h> 54 #include <linux/slab.h> 55 #include <net/datalink.h> 56 #include <net/psnap.h> 57 #include <net/sock.h> 58 #include <net/tcp_states.h> 59 #include <net/route.h> 60 #include <net/compat.h> 61 #include <linux/atalk.h> 62 #include <linux/highmem.h> 63 64 struct datalink_proto *ddp_dl, *aarp_dl; 65 static const struct proto_ops atalk_dgram_ops; 66 67 /**************************************************************************\ 68 * * 69 * Handlers for the socket list. * 70 * * 71 \**************************************************************************/ 72 73 HLIST_HEAD(atalk_sockets); 74 DEFINE_RWLOCK(atalk_sockets_lock); 75 76 static inline void __atalk_insert_socket(struct sock *sk) 77 { 78 sk_add_node(sk, &atalk_sockets); 79 } 80 81 static inline void atalk_remove_socket(struct sock *sk) 82 { 83 write_lock_bh(&atalk_sockets_lock); 84 sk_del_node_init(sk); 85 write_unlock_bh(&atalk_sockets_lock); 86 } 87 88 static struct sock *atalk_search_socket(struct sockaddr_at *to, 89 struct atalk_iface *atif) 90 { 91 struct sock *s; 92 93 read_lock_bh(&atalk_sockets_lock); 94 sk_for_each(s, &atalk_sockets) { 95 struct atalk_sock *at = at_sk(s); 96 97 if (to->sat_port != at->src_port) 98 continue; 99 100 if (to->sat_addr.s_net == ATADDR_ANYNET && 101 to->sat_addr.s_node == ATADDR_BCAST) 102 goto found; 103 104 if (to->sat_addr.s_net == at->src_net && 105 (to->sat_addr.s_node == at->src_node || 106 to->sat_addr.s_node == ATADDR_BCAST || 107 to->sat_addr.s_node == ATADDR_ANYNODE)) 108 goto found; 109 110 /* XXXX.0 -- we got a request for this router. make sure 111 * that the node is appropriately set. */ 112 if (to->sat_addr.s_node == ATADDR_ANYNODE && 113 to->sat_addr.s_net != ATADDR_ANYNET && 114 atif->address.s_node == at->src_node) { 115 to->sat_addr.s_node = atif->address.s_node; 116 goto found; 117 } 118 } 119 s = NULL; 120 found: 121 read_unlock_bh(&atalk_sockets_lock); 122 return s; 123 } 124 125 /** 126 * atalk_find_or_insert_socket - Try to find a socket matching ADDR 127 * @sk: socket to insert in the list if it is not there already 128 * @sat: address to search for 129 * 130 * Try to find a socket matching ADDR in the socket list, if found then return 131 * it. If not, insert SK into the socket list. 132 * 133 * This entire operation must execute atomically. 134 */ 135 static struct sock *atalk_find_or_insert_socket(struct sock *sk, 136 struct sockaddr_at *sat) 137 { 138 struct sock *s; 139 struct atalk_sock *at; 140 141 write_lock_bh(&atalk_sockets_lock); 142 sk_for_each(s, &atalk_sockets) { 143 at = at_sk(s); 144 145 if (at->src_net == sat->sat_addr.s_net && 146 at->src_node == sat->sat_addr.s_node && 147 at->src_port == sat->sat_port) 148 goto found; 149 } 150 s = NULL; 151 __atalk_insert_socket(sk); /* Wheee, it's free, assign and insert. */ 152 found: 153 write_unlock_bh(&atalk_sockets_lock); 154 return s; 155 } 156 157 static void atalk_destroy_timer(struct timer_list *t) 158 { 159 struct sock *sk = from_timer(sk, t, sk_timer); 160 161 if (sk_has_allocations(sk)) { 162 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME; 163 add_timer(&sk->sk_timer); 164 } else 165 sock_put(sk); 166 } 167 168 static inline void atalk_destroy_socket(struct sock *sk) 169 { 170 atalk_remove_socket(sk); 171 skb_queue_purge(&sk->sk_receive_queue); 172 173 if (sk_has_allocations(sk)) { 174 timer_setup(&sk->sk_timer, atalk_destroy_timer, 0); 175 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME; 176 add_timer(&sk->sk_timer); 177 } else 178 sock_put(sk); 179 } 180 181 /**************************************************************************\ 182 * * 183 * Routing tables for the AppleTalk socket layer. * 184 * * 185 \**************************************************************************/ 186 187 /* Anti-deadlock ordering is atalk_routes_lock --> iface_lock -DaveM */ 188 struct atalk_route *atalk_routes; 189 DEFINE_RWLOCK(atalk_routes_lock); 190 191 struct atalk_iface *atalk_interfaces; 192 DEFINE_RWLOCK(atalk_interfaces_lock); 193 194 /* For probing devices or in a routerless network */ 195 struct atalk_route atrtr_default; 196 197 /* AppleTalk interface control */ 198 /* 199 * Drop a device. Doesn't drop any of its routes - that is the caller's 200 * problem. Called when we down the interface or delete the address. 201 */ 202 static void atif_drop_device(struct net_device *dev) 203 { 204 struct atalk_iface **iface = &atalk_interfaces; 205 struct atalk_iface *tmp; 206 207 write_lock_bh(&atalk_interfaces_lock); 208 while ((tmp = *iface) != NULL) { 209 if (tmp->dev == dev) { 210 *iface = tmp->next; 211 dev_put(dev); 212 kfree(tmp); 213 dev->atalk_ptr = NULL; 214 } else 215 iface = &tmp->next; 216 } 217 write_unlock_bh(&atalk_interfaces_lock); 218 } 219 220 static struct atalk_iface *atif_add_device(struct net_device *dev, 221 struct atalk_addr *sa) 222 { 223 struct atalk_iface *iface = kzalloc(sizeof(*iface), GFP_KERNEL); 224 225 if (!iface) 226 goto out; 227 228 dev_hold(dev); 229 iface->dev = dev; 230 dev->atalk_ptr = iface; 231 iface->address = *sa; 232 iface->status = 0; 233 234 write_lock_bh(&atalk_interfaces_lock); 235 iface->next = atalk_interfaces; 236 atalk_interfaces = iface; 237 write_unlock_bh(&atalk_interfaces_lock); 238 out: 239 return iface; 240 } 241 242 /* Perform phase 2 AARP probing on our tentative address */ 243 static int atif_probe_device(struct atalk_iface *atif) 244 { 245 int netrange = ntohs(atif->nets.nr_lastnet) - 246 ntohs(atif->nets.nr_firstnet) + 1; 247 int probe_net = ntohs(atif->address.s_net); 248 int probe_node = atif->address.s_node; 249 int netct, nodect; 250 251 /* Offset the network we start probing with */ 252 if (probe_net == ATADDR_ANYNET) { 253 probe_net = ntohs(atif->nets.nr_firstnet); 254 if (netrange) 255 probe_net += jiffies % netrange; 256 } 257 if (probe_node == ATADDR_ANYNODE) 258 probe_node = jiffies & 0xFF; 259 260 /* Scan the networks */ 261 atif->status |= ATIF_PROBE; 262 for (netct = 0; netct <= netrange; netct++) { 263 /* Sweep the available nodes from a given start */ 264 atif->address.s_net = htons(probe_net); 265 for (nodect = 0; nodect < 256; nodect++) { 266 atif->address.s_node = (nodect + probe_node) & 0xFF; 267 if (atif->address.s_node > 0 && 268 atif->address.s_node < 254) { 269 /* Probe a proposed address */ 270 aarp_probe_network(atif); 271 272 if (!(atif->status & ATIF_PROBE_FAIL)) { 273 atif->status &= ~ATIF_PROBE; 274 return 0; 275 } 276 } 277 atif->status &= ~ATIF_PROBE_FAIL; 278 } 279 probe_net++; 280 if (probe_net > ntohs(atif->nets.nr_lastnet)) 281 probe_net = ntohs(atif->nets.nr_firstnet); 282 } 283 atif->status &= ~ATIF_PROBE; 284 285 return -EADDRINUSE; /* Network is full... */ 286 } 287 288 289 /* Perform AARP probing for a proxy address */ 290 static int atif_proxy_probe_device(struct atalk_iface *atif, 291 struct atalk_addr *proxy_addr) 292 { 293 int netrange = ntohs(atif->nets.nr_lastnet) - 294 ntohs(atif->nets.nr_firstnet) + 1; 295 /* we probe the interface's network */ 296 int probe_net = ntohs(atif->address.s_net); 297 int probe_node = ATADDR_ANYNODE; /* we'll take anything */ 298 int netct, nodect; 299 300 /* Offset the network we start probing with */ 301 if (probe_net == ATADDR_ANYNET) { 302 probe_net = ntohs(atif->nets.nr_firstnet); 303 if (netrange) 304 probe_net += jiffies % netrange; 305 } 306 307 if (probe_node == ATADDR_ANYNODE) 308 probe_node = jiffies & 0xFF; 309 310 /* Scan the networks */ 311 for (netct = 0; netct <= netrange; netct++) { 312 /* Sweep the available nodes from a given start */ 313 proxy_addr->s_net = htons(probe_net); 314 for (nodect = 0; nodect < 256; nodect++) { 315 proxy_addr->s_node = (nodect + probe_node) & 0xFF; 316 if (proxy_addr->s_node > 0 && 317 proxy_addr->s_node < 254) { 318 /* Tell AARP to probe a proposed address */ 319 int ret = aarp_proxy_probe_network(atif, 320 proxy_addr); 321 322 if (ret != -EADDRINUSE) 323 return ret; 324 } 325 } 326 probe_net++; 327 if (probe_net > ntohs(atif->nets.nr_lastnet)) 328 probe_net = ntohs(atif->nets.nr_firstnet); 329 } 330 331 return -EADDRINUSE; /* Network is full... */ 332 } 333 334 335 struct atalk_addr *atalk_find_dev_addr(struct net_device *dev) 336 { 337 struct atalk_iface *iface = dev->atalk_ptr; 338 return iface ? &iface->address : NULL; 339 } 340 341 static struct atalk_addr *atalk_find_primary(void) 342 { 343 struct atalk_iface *fiface = NULL; 344 struct atalk_addr *retval; 345 struct atalk_iface *iface; 346 347 /* 348 * Return a point-to-point interface only if 349 * there is no non-ptp interface available. 350 */ 351 read_lock_bh(&atalk_interfaces_lock); 352 for (iface = atalk_interfaces; iface; iface = iface->next) { 353 if (!fiface && !(iface->dev->flags & IFF_LOOPBACK)) 354 fiface = iface; 355 if (!(iface->dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) { 356 retval = &iface->address; 357 goto out; 358 } 359 } 360 361 if (fiface) 362 retval = &fiface->address; 363 else if (atalk_interfaces) 364 retval = &atalk_interfaces->address; 365 else 366 retval = NULL; 367 out: 368 read_unlock_bh(&atalk_interfaces_lock); 369 return retval; 370 } 371 372 /* 373 * Find a match for 'any network' - ie any of our interfaces with that 374 * node number will do just nicely. 375 */ 376 static struct atalk_iface *atalk_find_anynet(int node, struct net_device *dev) 377 { 378 struct atalk_iface *iface = dev->atalk_ptr; 379 380 if (!iface || iface->status & ATIF_PROBE) 381 goto out_err; 382 383 if (node != ATADDR_BCAST && 384 iface->address.s_node != node && 385 node != ATADDR_ANYNODE) 386 goto out_err; 387 out: 388 return iface; 389 out_err: 390 iface = NULL; 391 goto out; 392 } 393 394 /* Find a match for a specific network:node pair */ 395 static struct atalk_iface *atalk_find_interface(__be16 net, int node) 396 { 397 struct atalk_iface *iface; 398 399 read_lock_bh(&atalk_interfaces_lock); 400 for (iface = atalk_interfaces; iface; iface = iface->next) { 401 if ((node == ATADDR_BCAST || 402 node == ATADDR_ANYNODE || 403 iface->address.s_node == node) && 404 iface->address.s_net == net && 405 !(iface->status & ATIF_PROBE)) 406 break; 407 408 /* XXXX.0 -- net.0 returns the iface associated with net */ 409 if (node == ATADDR_ANYNODE && net != ATADDR_ANYNET && 410 ntohs(iface->nets.nr_firstnet) <= ntohs(net) && 411 ntohs(net) <= ntohs(iface->nets.nr_lastnet)) 412 break; 413 } 414 read_unlock_bh(&atalk_interfaces_lock); 415 return iface; 416 } 417 418 419 /* 420 * Find a route for an AppleTalk packet. This ought to get cached in 421 * the socket (later on...). We know about host routes and the fact 422 * that a route must be direct to broadcast. 423 */ 424 static struct atalk_route *atrtr_find(struct atalk_addr *target) 425 { 426 /* 427 * we must search through all routes unless we find a 428 * host route, because some host routes might overlap 429 * network routes 430 */ 431 struct atalk_route *net_route = NULL; 432 struct atalk_route *r; 433 434 read_lock_bh(&atalk_routes_lock); 435 for (r = atalk_routes; r; r = r->next) { 436 if (!(r->flags & RTF_UP)) 437 continue; 438 439 if (r->target.s_net == target->s_net) { 440 if (r->flags & RTF_HOST) { 441 /* 442 * if this host route is for the target, 443 * the we're done 444 */ 445 if (r->target.s_node == target->s_node) 446 goto out; 447 } else 448 /* 449 * this route will work if there isn't a 450 * direct host route, so cache it 451 */ 452 net_route = r; 453 } 454 } 455 456 /* 457 * if we found a network route but not a direct host 458 * route, then return it 459 */ 460 if (net_route) 461 r = net_route; 462 else if (atrtr_default.dev) 463 r = &atrtr_default; 464 else /* No route can be found */ 465 r = NULL; 466 out: 467 read_unlock_bh(&atalk_routes_lock); 468 return r; 469 } 470 471 472 /* 473 * Given an AppleTalk network, find the device to use. This can be 474 * a simple lookup. 475 */ 476 struct net_device *atrtr_get_dev(struct atalk_addr *sa) 477 { 478 struct atalk_route *atr = atrtr_find(sa); 479 return atr ? atr->dev : NULL; 480 } 481 482 /* Set up a default router */ 483 static void atrtr_set_default(struct net_device *dev) 484 { 485 atrtr_default.dev = dev; 486 atrtr_default.flags = RTF_UP; 487 atrtr_default.gateway.s_net = htons(0); 488 atrtr_default.gateway.s_node = 0; 489 } 490 491 /* 492 * Add a router. Basically make sure it looks valid and stuff the 493 * entry in the list. While it uses netranges we always set them to one 494 * entry to work like netatalk. 495 */ 496 static int atrtr_create(struct rtentry *r, struct net_device *devhint) 497 { 498 struct sockaddr_at *ta = (struct sockaddr_at *)&r->rt_dst; 499 struct sockaddr_at *ga = (struct sockaddr_at *)&r->rt_gateway; 500 struct atalk_route *rt; 501 struct atalk_iface *iface, *riface; 502 int retval = -EINVAL; 503 504 /* 505 * Fixme: Raise/Lower a routing change semaphore for these 506 * operations. 507 */ 508 509 /* Validate the request */ 510 if (ta->sat_family != AF_APPLETALK || 511 (!devhint && ga->sat_family != AF_APPLETALK)) 512 goto out; 513 514 /* Now walk the routing table and make our decisions */ 515 write_lock_bh(&atalk_routes_lock); 516 for (rt = atalk_routes; rt; rt = rt->next) { 517 if (r->rt_flags != rt->flags) 518 continue; 519 520 if (ta->sat_addr.s_net == rt->target.s_net) { 521 if (!(rt->flags & RTF_HOST)) 522 break; 523 if (ta->sat_addr.s_node == rt->target.s_node) 524 break; 525 } 526 } 527 528 if (!devhint) { 529 riface = NULL; 530 531 read_lock_bh(&atalk_interfaces_lock); 532 for (iface = atalk_interfaces; iface; iface = iface->next) { 533 if (!riface && 534 ntohs(ga->sat_addr.s_net) >= 535 ntohs(iface->nets.nr_firstnet) && 536 ntohs(ga->sat_addr.s_net) <= 537 ntohs(iface->nets.nr_lastnet)) 538 riface = iface; 539 540 if (ga->sat_addr.s_net == iface->address.s_net && 541 ga->sat_addr.s_node == iface->address.s_node) 542 riface = iface; 543 } 544 read_unlock_bh(&atalk_interfaces_lock); 545 546 retval = -ENETUNREACH; 547 if (!riface) 548 goto out_unlock; 549 550 devhint = riface->dev; 551 } 552 553 if (!rt) { 554 rt = kzalloc(sizeof(*rt), GFP_ATOMIC); 555 556 retval = -ENOBUFS; 557 if (!rt) 558 goto out_unlock; 559 560 rt->next = atalk_routes; 561 atalk_routes = rt; 562 } 563 564 /* Fill in the routing entry */ 565 rt->target = ta->sat_addr; 566 dev_hold(devhint); 567 rt->dev = devhint; 568 rt->flags = r->rt_flags; 569 rt->gateway = ga->sat_addr; 570 571 retval = 0; 572 out_unlock: 573 write_unlock_bh(&atalk_routes_lock); 574 out: 575 return retval; 576 } 577 578 /* Delete a route. Find it and discard it */ 579 static int atrtr_delete(struct atalk_addr *addr) 580 { 581 struct atalk_route **r = &atalk_routes; 582 int retval = 0; 583 struct atalk_route *tmp; 584 585 write_lock_bh(&atalk_routes_lock); 586 while ((tmp = *r) != NULL) { 587 if (tmp->target.s_net == addr->s_net && 588 (!(tmp->flags&RTF_GATEWAY) || 589 tmp->target.s_node == addr->s_node)) { 590 *r = tmp->next; 591 dev_put(tmp->dev); 592 kfree(tmp); 593 goto out; 594 } 595 r = &tmp->next; 596 } 597 retval = -ENOENT; 598 out: 599 write_unlock_bh(&atalk_routes_lock); 600 return retval; 601 } 602 603 /* 604 * Called when a device is downed. Just throw away any routes 605 * via it. 606 */ 607 static void atrtr_device_down(struct net_device *dev) 608 { 609 struct atalk_route **r = &atalk_routes; 610 struct atalk_route *tmp; 611 612 write_lock_bh(&atalk_routes_lock); 613 while ((tmp = *r) != NULL) { 614 if (tmp->dev == dev) { 615 *r = tmp->next; 616 dev_put(dev); 617 kfree(tmp); 618 } else 619 r = &tmp->next; 620 } 621 write_unlock_bh(&atalk_routes_lock); 622 623 if (atrtr_default.dev == dev) 624 atrtr_set_default(NULL); 625 } 626 627 /* Actually down the interface */ 628 static inline void atalk_dev_down(struct net_device *dev) 629 { 630 atrtr_device_down(dev); /* Remove all routes for the device */ 631 aarp_device_down(dev); /* Remove AARP entries for the device */ 632 atif_drop_device(dev); /* Remove the device */ 633 } 634 635 /* 636 * A device event has occurred. Watch for devices going down and 637 * delete our use of them (iface and route). 638 */ 639 static int ddp_device_event(struct notifier_block *this, unsigned long event, 640 void *ptr) 641 { 642 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 643 644 if (!net_eq(dev_net(dev), &init_net)) 645 return NOTIFY_DONE; 646 647 if (event == NETDEV_DOWN) 648 /* Discard any use of this */ 649 atalk_dev_down(dev); 650 651 return NOTIFY_DONE; 652 } 653 654 /* ioctl calls. Shouldn't even need touching */ 655 /* Device configuration ioctl calls */ 656 static int atif_ioctl(int cmd, void __user *arg) 657 { 658 static char aarp_mcast[6] = { 0x09, 0x00, 0x00, 0xFF, 0xFF, 0xFF }; 659 struct ifreq atreq; 660 struct atalk_netrange *nr; 661 struct sockaddr_at *sa; 662 struct net_device *dev; 663 struct atalk_iface *atif; 664 int ct; 665 int limit; 666 struct rtentry rtdef; 667 int add_route; 668 669 if (copy_from_user(&atreq, arg, sizeof(atreq))) 670 return -EFAULT; 671 672 dev = __dev_get_by_name(&init_net, atreq.ifr_name); 673 if (!dev) 674 return -ENODEV; 675 676 sa = (struct sockaddr_at *)&atreq.ifr_addr; 677 atif = atalk_find_dev(dev); 678 679 switch (cmd) { 680 case SIOCSIFADDR: 681 if (!capable(CAP_NET_ADMIN)) 682 return -EPERM; 683 if (sa->sat_family != AF_APPLETALK) 684 return -EINVAL; 685 if (dev->type != ARPHRD_ETHER && 686 dev->type != ARPHRD_LOOPBACK && 687 dev->type != ARPHRD_LOCALTLK && 688 dev->type != ARPHRD_PPP) 689 return -EPROTONOSUPPORT; 690 691 nr = (struct atalk_netrange *)&sa->sat_zero[0]; 692 add_route = 1; 693 694 /* 695 * if this is a point-to-point iface, and we already 696 * have an iface for this AppleTalk address, then we 697 * should not add a route 698 */ 699 if ((dev->flags & IFF_POINTOPOINT) && 700 atalk_find_interface(sa->sat_addr.s_net, 701 sa->sat_addr.s_node)) { 702 printk(KERN_DEBUG "AppleTalk: point-to-point " 703 "interface added with " 704 "existing address\n"); 705 add_route = 0; 706 } 707 708 /* 709 * Phase 1 is fine on LocalTalk but we don't do 710 * EtherTalk phase 1. Anyone wanting to add it go ahead. 711 */ 712 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2) 713 return -EPROTONOSUPPORT; 714 if (sa->sat_addr.s_node == ATADDR_BCAST || 715 sa->sat_addr.s_node == 254) 716 return -EINVAL; 717 if (atif) { 718 /* Already setting address */ 719 if (atif->status & ATIF_PROBE) 720 return -EBUSY; 721 722 atif->address.s_net = sa->sat_addr.s_net; 723 atif->address.s_node = sa->sat_addr.s_node; 724 atrtr_device_down(dev); /* Flush old routes */ 725 } else { 726 atif = atif_add_device(dev, &sa->sat_addr); 727 if (!atif) 728 return -ENOMEM; 729 } 730 atif->nets = *nr; 731 732 /* 733 * Check if the chosen address is used. If so we 734 * error and atalkd will try another. 735 */ 736 737 if (!(dev->flags & IFF_LOOPBACK) && 738 !(dev->flags & IFF_POINTOPOINT) && 739 atif_probe_device(atif) < 0) { 740 atif_drop_device(dev); 741 return -EADDRINUSE; 742 } 743 744 /* Hey it worked - add the direct routes */ 745 sa = (struct sockaddr_at *)&rtdef.rt_gateway; 746 sa->sat_family = AF_APPLETALK; 747 sa->sat_addr.s_net = atif->address.s_net; 748 sa->sat_addr.s_node = atif->address.s_node; 749 sa = (struct sockaddr_at *)&rtdef.rt_dst; 750 rtdef.rt_flags = RTF_UP; 751 sa->sat_family = AF_APPLETALK; 752 sa->sat_addr.s_node = ATADDR_ANYNODE; 753 if (dev->flags & IFF_LOOPBACK || 754 dev->flags & IFF_POINTOPOINT) 755 rtdef.rt_flags |= RTF_HOST; 756 757 /* Routerless initial state */ 758 if (nr->nr_firstnet == htons(0) && 759 nr->nr_lastnet == htons(0xFFFE)) { 760 sa->sat_addr.s_net = atif->address.s_net; 761 atrtr_create(&rtdef, dev); 762 atrtr_set_default(dev); 763 } else { 764 limit = ntohs(nr->nr_lastnet); 765 if (limit - ntohs(nr->nr_firstnet) > 4096) { 766 printk(KERN_WARNING "Too many routes/" 767 "iface.\n"); 768 return -EINVAL; 769 } 770 if (add_route) 771 for (ct = ntohs(nr->nr_firstnet); 772 ct <= limit; ct++) { 773 sa->sat_addr.s_net = htons(ct); 774 atrtr_create(&rtdef, dev); 775 } 776 } 777 dev_mc_add_global(dev, aarp_mcast); 778 return 0; 779 780 case SIOCGIFADDR: 781 if (!atif) 782 return -EADDRNOTAVAIL; 783 784 sa->sat_family = AF_APPLETALK; 785 sa->sat_addr = atif->address; 786 break; 787 788 case SIOCGIFBRDADDR: 789 if (!atif) 790 return -EADDRNOTAVAIL; 791 792 sa->sat_family = AF_APPLETALK; 793 sa->sat_addr.s_net = atif->address.s_net; 794 sa->sat_addr.s_node = ATADDR_BCAST; 795 break; 796 797 case SIOCATALKDIFADDR: 798 case SIOCDIFADDR: 799 if (!capable(CAP_NET_ADMIN)) 800 return -EPERM; 801 if (sa->sat_family != AF_APPLETALK) 802 return -EINVAL; 803 atalk_dev_down(dev); 804 break; 805 806 case SIOCSARP: 807 if (!capable(CAP_NET_ADMIN)) 808 return -EPERM; 809 if (sa->sat_family != AF_APPLETALK) 810 return -EINVAL; 811 /* 812 * for now, we only support proxy AARP on ELAP; 813 * we should be able to do it for LocalTalk, too. 814 */ 815 if (dev->type != ARPHRD_ETHER) 816 return -EPROTONOSUPPORT; 817 818 /* 819 * atif points to the current interface on this network; 820 * we aren't concerned about its current status (at 821 * least for now), but it has all the settings about 822 * the network we're going to probe. Consequently, it 823 * must exist. 824 */ 825 if (!atif) 826 return -EADDRNOTAVAIL; 827 828 nr = (struct atalk_netrange *)&(atif->nets); 829 /* 830 * Phase 1 is fine on Localtalk but we don't do 831 * Ethertalk phase 1. Anyone wanting to add it go ahead. 832 */ 833 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2) 834 return -EPROTONOSUPPORT; 835 836 if (sa->sat_addr.s_node == ATADDR_BCAST || 837 sa->sat_addr.s_node == 254) 838 return -EINVAL; 839 840 /* 841 * Check if the chosen address is used. If so we 842 * error and ATCP will try another. 843 */ 844 if (atif_proxy_probe_device(atif, &(sa->sat_addr)) < 0) 845 return -EADDRINUSE; 846 847 /* 848 * We now have an address on the local network, and 849 * the AARP code will defend it for us until we take it 850 * down. We don't set up any routes right now, because 851 * ATCP will install them manually via SIOCADDRT. 852 */ 853 break; 854 855 case SIOCDARP: 856 if (!capable(CAP_NET_ADMIN)) 857 return -EPERM; 858 if (sa->sat_family != AF_APPLETALK) 859 return -EINVAL; 860 if (!atif) 861 return -EADDRNOTAVAIL; 862 863 /* give to aarp module to remove proxy entry */ 864 aarp_proxy_remove(atif->dev, &(sa->sat_addr)); 865 return 0; 866 } 867 868 return copy_to_user(arg, &atreq, sizeof(atreq)) ? -EFAULT : 0; 869 } 870 871 static int atrtr_ioctl_addrt(struct rtentry *rt) 872 { 873 struct net_device *dev = NULL; 874 875 if (rt->rt_dev) { 876 char name[IFNAMSIZ]; 877 878 if (copy_from_user(name, rt->rt_dev, IFNAMSIZ-1)) 879 return -EFAULT; 880 name[IFNAMSIZ-1] = '\0'; 881 882 dev = __dev_get_by_name(&init_net, name); 883 if (!dev) 884 return -ENODEV; 885 } 886 return atrtr_create(rt, dev); 887 } 888 889 /* Routing ioctl() calls */ 890 static int atrtr_ioctl(unsigned int cmd, void __user *arg) 891 { 892 struct rtentry rt; 893 894 if (copy_from_user(&rt, arg, sizeof(rt))) 895 return -EFAULT; 896 897 switch (cmd) { 898 case SIOCDELRT: 899 if (rt.rt_dst.sa_family != AF_APPLETALK) 900 return -EINVAL; 901 return atrtr_delete(&((struct sockaddr_at *) 902 &rt.rt_dst)->sat_addr); 903 904 case SIOCADDRT: 905 return atrtr_ioctl_addrt(&rt); 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 const skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 955 WARN_ON(start > offset + len); 956 957 end = start + skb_frag_size(frag); 958 if ((copy = end - offset) > 0) { 959 u8 *vaddr; 960 961 if (copy > len) 962 copy = len; 963 vaddr = kmap_atomic(skb_frag_page(frag)); 964 sum = atalk_sum_partial(vaddr + skb_frag_off(frag) + 965 offset - start, copy, sum); 966 kunmap_atomic(vaddr); 967 968 if (!(len -= copy)) 969 return sum; 970 offset += copy; 971 } 972 start = end; 973 } 974 975 skb_walk_frags(skb, frag_iter) { 976 int end; 977 978 WARN_ON(start > offset + len); 979 980 end = start + frag_iter->len; 981 if ((copy = end - offset) > 0) { 982 if (copy > len) 983 copy = len; 984 sum = atalk_sum_skb(frag_iter, offset - start, 985 copy, sum); 986 if ((len -= copy) == 0) 987 return sum; 988 offset += copy; 989 } 990 start = end; 991 } 992 993 BUG_ON(len > 0); 994 995 return sum; 996 } 997 998 static __be16 atalk_checksum(const struct sk_buff *skb, int len) 999 { 1000 unsigned long sum; 1001 1002 /* skip header 4 bytes */ 1003 sum = atalk_sum_skb(skb, 4, len-4, 0); 1004 1005 /* Use 0xFFFF for 0. 0 itself means none */ 1006 return sum ? htons((unsigned short)sum) : htons(0xFFFF); 1007 } 1008 1009 static struct proto ddp_proto = { 1010 .name = "DDP", 1011 .owner = THIS_MODULE, 1012 .obj_size = sizeof(struct atalk_sock), 1013 }; 1014 1015 /* 1016 * Create a socket. Initialise the socket, blank the addresses 1017 * set the state. 1018 */ 1019 static int atalk_create(struct net *net, struct socket *sock, int protocol, 1020 int kern) 1021 { 1022 struct sock *sk; 1023 int rc = -ESOCKTNOSUPPORT; 1024 1025 if (!net_eq(net, &init_net)) 1026 return -EAFNOSUPPORT; 1027 1028 /* 1029 * We permit SOCK_DGRAM and RAW is an extension. It is trivial to do 1030 * and gives you the full ELAP frame. Should be handy for CAP 8) 1031 */ 1032 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) 1033 goto out; 1034 1035 rc = -EPERM; 1036 if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW)) 1037 goto out; 1038 1039 rc = -ENOMEM; 1040 sk = sk_alloc(net, PF_APPLETALK, GFP_KERNEL, &ddp_proto, kern); 1041 if (!sk) 1042 goto out; 1043 rc = 0; 1044 sock->ops = &atalk_dgram_ops; 1045 sock_init_data(sock, sk); 1046 1047 /* Checksums on by default */ 1048 sock_set_flag(sk, SOCK_ZAPPED); 1049 out: 1050 return rc; 1051 } 1052 1053 /* Free a socket. No work needed */ 1054 static int atalk_release(struct socket *sock) 1055 { 1056 struct sock *sk = sock->sk; 1057 1058 if (sk) { 1059 sock_hold(sk); 1060 lock_sock(sk); 1061 1062 sock_orphan(sk); 1063 sock->sk = NULL; 1064 atalk_destroy_socket(sk); 1065 1066 release_sock(sk); 1067 sock_put(sk); 1068 } 1069 return 0; 1070 } 1071 1072 /** 1073 * atalk_pick_and_bind_port - Pick a source port when one is not given 1074 * @sk: socket to insert into the tables 1075 * @sat: address to search for 1076 * 1077 * Pick a source port when one is not given. If we can find a suitable free 1078 * one, we insert the socket into the tables using it. 1079 * 1080 * This whole operation must be atomic. 1081 */ 1082 static int atalk_pick_and_bind_port(struct sock *sk, struct sockaddr_at *sat) 1083 { 1084 int retval; 1085 1086 write_lock_bh(&atalk_sockets_lock); 1087 1088 for (sat->sat_port = ATPORT_RESERVED; 1089 sat->sat_port < ATPORT_LAST; 1090 sat->sat_port++) { 1091 struct sock *s; 1092 1093 sk_for_each(s, &atalk_sockets) { 1094 struct atalk_sock *at = at_sk(s); 1095 1096 if (at->src_net == sat->sat_addr.s_net && 1097 at->src_node == sat->sat_addr.s_node && 1098 at->src_port == sat->sat_port) 1099 goto try_next_port; 1100 } 1101 1102 /* Wheee, it's free, assign and insert. */ 1103 __atalk_insert_socket(sk); 1104 at_sk(sk)->src_port = sat->sat_port; 1105 retval = 0; 1106 goto out; 1107 1108 try_next_port:; 1109 } 1110 1111 retval = -EBUSY; 1112 out: 1113 write_unlock_bh(&atalk_sockets_lock); 1114 return retval; 1115 } 1116 1117 static int atalk_autobind(struct sock *sk) 1118 { 1119 struct atalk_sock *at = at_sk(sk); 1120 struct sockaddr_at sat; 1121 struct atalk_addr *ap = atalk_find_primary(); 1122 int n = -EADDRNOTAVAIL; 1123 1124 if (!ap || ap->s_net == htons(ATADDR_ANYNET)) 1125 goto out; 1126 1127 at->src_net = sat.sat_addr.s_net = ap->s_net; 1128 at->src_node = sat.sat_addr.s_node = ap->s_node; 1129 1130 n = atalk_pick_and_bind_port(sk, &sat); 1131 if (!n) 1132 sock_reset_flag(sk, SOCK_ZAPPED); 1133 out: 1134 return n; 1135 } 1136 1137 /* Set the address 'our end' of the connection */ 1138 static int atalk_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 1139 { 1140 struct sockaddr_at *addr = (struct sockaddr_at *)uaddr; 1141 struct sock *sk = sock->sk; 1142 struct atalk_sock *at = at_sk(sk); 1143 int err; 1144 1145 if (!sock_flag(sk, SOCK_ZAPPED) || 1146 addr_len != sizeof(struct sockaddr_at)) 1147 return -EINVAL; 1148 1149 if (addr->sat_family != AF_APPLETALK) 1150 return -EAFNOSUPPORT; 1151 1152 lock_sock(sk); 1153 if (addr->sat_addr.s_net == htons(ATADDR_ANYNET)) { 1154 struct atalk_addr *ap = atalk_find_primary(); 1155 1156 err = -EADDRNOTAVAIL; 1157 if (!ap) 1158 goto out; 1159 1160 at->src_net = addr->sat_addr.s_net = ap->s_net; 1161 at->src_node = addr->sat_addr.s_node = ap->s_node; 1162 } else { 1163 err = -EADDRNOTAVAIL; 1164 if (!atalk_find_interface(addr->sat_addr.s_net, 1165 addr->sat_addr.s_node)) 1166 goto out; 1167 1168 at->src_net = addr->sat_addr.s_net; 1169 at->src_node = addr->sat_addr.s_node; 1170 } 1171 1172 if (addr->sat_port == ATADDR_ANYPORT) { 1173 err = atalk_pick_and_bind_port(sk, addr); 1174 1175 if (err < 0) 1176 goto out; 1177 } else { 1178 at->src_port = addr->sat_port; 1179 1180 err = -EADDRINUSE; 1181 if (atalk_find_or_insert_socket(sk, addr)) 1182 goto out; 1183 } 1184 1185 sock_reset_flag(sk, SOCK_ZAPPED); 1186 err = 0; 1187 out: 1188 release_sock(sk); 1189 return err; 1190 } 1191 1192 /* Set the address we talk to */ 1193 static int atalk_connect(struct socket *sock, struct sockaddr *uaddr, 1194 int addr_len, int flags) 1195 { 1196 struct sock *sk = sock->sk; 1197 struct atalk_sock *at = at_sk(sk); 1198 struct sockaddr_at *addr; 1199 int err; 1200 1201 sk->sk_state = TCP_CLOSE; 1202 sock->state = SS_UNCONNECTED; 1203 1204 if (addr_len != sizeof(*addr)) 1205 return -EINVAL; 1206 1207 addr = (struct sockaddr_at *)uaddr; 1208 1209 if (addr->sat_family != AF_APPLETALK) 1210 return -EAFNOSUPPORT; 1211 1212 if (addr->sat_addr.s_node == ATADDR_BCAST && 1213 !sock_flag(sk, SOCK_BROADCAST)) { 1214 #if 1 1215 pr_warn("atalk_connect: %s is broken and did not set SO_BROADCAST.\n", 1216 current->comm); 1217 #else 1218 return -EACCES; 1219 #endif 1220 } 1221 1222 lock_sock(sk); 1223 err = -EBUSY; 1224 if (sock_flag(sk, SOCK_ZAPPED)) 1225 if (atalk_autobind(sk) < 0) 1226 goto out; 1227 1228 err = -ENETUNREACH; 1229 if (!atrtr_get_dev(&addr->sat_addr)) 1230 goto out; 1231 1232 at->dest_port = addr->sat_port; 1233 at->dest_net = addr->sat_addr.s_net; 1234 at->dest_node = addr->sat_addr.s_node; 1235 1236 sock->state = SS_CONNECTED; 1237 sk->sk_state = TCP_ESTABLISHED; 1238 err = 0; 1239 out: 1240 release_sock(sk); 1241 return err; 1242 } 1243 1244 /* 1245 * Find the name of an AppleTalk socket. Just copy the right 1246 * fields into the sockaddr. 1247 */ 1248 static int atalk_getname(struct socket *sock, struct sockaddr *uaddr, 1249 int peer) 1250 { 1251 struct sockaddr_at sat; 1252 struct sock *sk = sock->sk; 1253 struct atalk_sock *at = at_sk(sk); 1254 int err; 1255 1256 lock_sock(sk); 1257 err = -ENOBUFS; 1258 if (sock_flag(sk, SOCK_ZAPPED)) 1259 if (atalk_autobind(sk) < 0) 1260 goto out; 1261 1262 memset(&sat, 0, sizeof(sat)); 1263 1264 if (peer) { 1265 err = -ENOTCONN; 1266 if (sk->sk_state != TCP_ESTABLISHED) 1267 goto out; 1268 1269 sat.sat_addr.s_net = at->dest_net; 1270 sat.sat_addr.s_node = at->dest_node; 1271 sat.sat_port = at->dest_port; 1272 } else { 1273 sat.sat_addr.s_net = at->src_net; 1274 sat.sat_addr.s_node = at->src_node; 1275 sat.sat_port = at->src_port; 1276 } 1277 1278 sat.sat_family = AF_APPLETALK; 1279 memcpy(uaddr, &sat, sizeof(sat)); 1280 err = sizeof(struct sockaddr_at); 1281 1282 out: 1283 release_sock(sk); 1284 return err; 1285 } 1286 1287 #if IS_ENABLED(CONFIG_IPDDP) 1288 static __inline__ int is_ip_over_ddp(struct sk_buff *skb) 1289 { 1290 return skb->data[12] == 22; 1291 } 1292 1293 static int handle_ip_over_ddp(struct sk_buff *skb) 1294 { 1295 struct net_device *dev = __dev_get_by_name(&init_net, "ipddp0"); 1296 struct net_device_stats *stats; 1297 1298 /* This needs to be able to handle ipddp"N" devices */ 1299 if (!dev) { 1300 kfree_skb(skb); 1301 return NET_RX_DROP; 1302 } 1303 1304 skb->protocol = htons(ETH_P_IP); 1305 skb_pull(skb, 13); 1306 skb->dev = dev; 1307 skb_reset_transport_header(skb); 1308 1309 stats = netdev_priv(dev); 1310 stats->rx_packets++; 1311 stats->rx_bytes += skb->len + 13; 1312 return netif_rx(skb); /* Send the SKB up to a higher place. */ 1313 } 1314 #else 1315 /* make it easy for gcc to optimize this test out, i.e. kill the code */ 1316 #define is_ip_over_ddp(skb) 0 1317 #define handle_ip_over_ddp(skb) 0 1318 #endif 1319 1320 static int atalk_route_packet(struct sk_buff *skb, struct net_device *dev, 1321 struct ddpehdr *ddp, __u16 len_hops, int origlen) 1322 { 1323 struct atalk_route *rt; 1324 struct atalk_addr ta; 1325 1326 /* 1327 * Don't route multicast, etc., packets, or packets sent to "this 1328 * network" 1329 */ 1330 if (skb->pkt_type != PACKET_HOST || !ddp->deh_dnet) { 1331 /* 1332 * FIXME: 1333 * 1334 * Can it ever happen that a packet is from a PPP iface and 1335 * needs to be broadcast onto the default network? 1336 */ 1337 if (dev->type == ARPHRD_PPP) 1338 printk(KERN_DEBUG "AppleTalk: didn't forward broadcast " 1339 "packet received from PPP iface\n"); 1340 goto free_it; 1341 } 1342 1343 ta.s_net = ddp->deh_dnet; 1344 ta.s_node = ddp->deh_dnode; 1345 1346 /* Route the packet */ 1347 rt = atrtr_find(&ta); 1348 /* increment hops count */ 1349 len_hops += 1 << 10; 1350 if (!rt || !(len_hops & (15 << 10))) 1351 goto free_it; 1352 1353 /* FIXME: use skb->cb to be able to use shared skbs */ 1354 1355 /* 1356 * Route goes through another gateway, so set the target to the 1357 * gateway instead. 1358 */ 1359 1360 if (rt->flags & RTF_GATEWAY) { 1361 ta.s_net = rt->gateway.s_net; 1362 ta.s_node = rt->gateway.s_node; 1363 } 1364 1365 /* Fix up skb->len field */ 1366 skb_trim(skb, min_t(unsigned int, origlen, 1367 (rt->dev->hard_header_len + 1368 ddp_dl->header_length + (len_hops & 1023)))); 1369 1370 /* FIXME: use skb->cb to be able to use shared skbs */ 1371 ddp->deh_len_hops = htons(len_hops); 1372 1373 /* 1374 * Send the buffer onwards 1375 * 1376 * Now we must always be careful. If it's come from LocalTalk to 1377 * EtherTalk it might not fit 1378 * 1379 * Order matters here: If a packet has to be copied to make a new 1380 * headroom (rare hopefully) then it won't need unsharing. 1381 * 1382 * Note. ddp-> becomes invalid at the realloc. 1383 */ 1384 if (skb_headroom(skb) < 22) { 1385 /* 22 bytes - 12 ether, 2 len, 3 802.2 5 snap */ 1386 struct sk_buff *nskb = skb_realloc_headroom(skb, 32); 1387 kfree_skb(skb); 1388 skb = nskb; 1389 } else 1390 skb = skb_unshare(skb, GFP_ATOMIC); 1391 1392 /* 1393 * If the buffer didn't vanish into the lack of space bitbucket we can 1394 * send it. 1395 */ 1396 if (skb == NULL) 1397 goto drop; 1398 1399 if (aarp_send_ddp(rt->dev, skb, &ta, NULL) == NET_XMIT_DROP) 1400 return NET_RX_DROP; 1401 return NET_RX_SUCCESS; 1402 free_it: 1403 kfree_skb(skb); 1404 drop: 1405 return NET_RX_DROP; 1406 } 1407 1408 /** 1409 * atalk_rcv - Receive a packet (in skb) from device dev 1410 * @skb - packet received 1411 * @dev - network device where the packet comes from 1412 * @pt - packet type 1413 * 1414 * Receive a packet (in skb) from device dev. This has come from the SNAP 1415 * decoder, and on entry skb->transport_header is the DDP header, skb->len 1416 * is the DDP header, skb->len is the DDP length. The physical headers 1417 * have been extracted. PPP should probably pass frames marked as for this 1418 * layer. [ie ARPHRD_ETHERTALK] 1419 */ 1420 static int atalk_rcv(struct sk_buff *skb, struct net_device *dev, 1421 struct packet_type *pt, struct net_device *orig_dev) 1422 { 1423 struct ddpehdr *ddp; 1424 struct sock *sock; 1425 struct atalk_iface *atif; 1426 struct sockaddr_at tosat; 1427 int origlen; 1428 __u16 len_hops; 1429 1430 if (!net_eq(dev_net(dev), &init_net)) 1431 goto drop; 1432 1433 /* Don't mangle buffer if shared */ 1434 if (!(skb = skb_share_check(skb, GFP_ATOMIC))) 1435 goto out; 1436 1437 /* Size check and make sure header is contiguous */ 1438 if (!pskb_may_pull(skb, sizeof(*ddp))) 1439 goto drop; 1440 1441 ddp = ddp_hdr(skb); 1442 1443 len_hops = ntohs(ddp->deh_len_hops); 1444 1445 /* Trim buffer in case of stray trailing data */ 1446 origlen = skb->len; 1447 skb_trim(skb, min_t(unsigned int, skb->len, len_hops & 1023)); 1448 1449 /* 1450 * Size check to see if ddp->deh_len was crap 1451 * (Otherwise we'll detonate most spectacularly 1452 * in the middle of atalk_checksum() or recvmsg()). 1453 */ 1454 if (skb->len < sizeof(*ddp) || skb->len < (len_hops & 1023)) { 1455 pr_debug("AppleTalk: dropping corrupted frame (deh_len=%u, " 1456 "skb->len=%u)\n", len_hops & 1023, skb->len); 1457 goto drop; 1458 } 1459 1460 /* 1461 * Any checksums. Note we don't do htons() on this == is assumed to be 1462 * valid for net byte orders all over the networking code... 1463 */ 1464 if (ddp->deh_sum && 1465 atalk_checksum(skb, len_hops & 1023) != ddp->deh_sum) 1466 /* Not a valid AppleTalk frame - dustbin time */ 1467 goto drop; 1468 1469 /* Check the packet is aimed at us */ 1470 if (!ddp->deh_dnet) /* Net 0 is 'this network' */ 1471 atif = atalk_find_anynet(ddp->deh_dnode, dev); 1472 else 1473 atif = atalk_find_interface(ddp->deh_dnet, ddp->deh_dnode); 1474 1475 if (!atif) { 1476 /* Not ours, so we route the packet via the correct 1477 * AppleTalk iface 1478 */ 1479 return atalk_route_packet(skb, dev, ddp, len_hops, origlen); 1480 } 1481 1482 /* if IP over DDP is not selected this code will be optimized out */ 1483 if (is_ip_over_ddp(skb)) 1484 return handle_ip_over_ddp(skb); 1485 /* 1486 * Which socket - atalk_search_socket() looks for a *full match* 1487 * of the <net, node, port> tuple. 1488 */ 1489 tosat.sat_addr.s_net = ddp->deh_dnet; 1490 tosat.sat_addr.s_node = ddp->deh_dnode; 1491 tosat.sat_port = ddp->deh_dport; 1492 1493 sock = atalk_search_socket(&tosat, atif); 1494 if (!sock) /* But not one of our sockets */ 1495 goto drop; 1496 1497 /* Queue packet (standard) */ 1498 if (sock_queue_rcv_skb(sock, skb) < 0) 1499 goto drop; 1500 1501 return NET_RX_SUCCESS; 1502 1503 drop: 1504 kfree_skb(skb); 1505 out: 1506 return NET_RX_DROP; 1507 1508 } 1509 1510 /* 1511 * Receive a LocalTalk frame. We make some demands on the caller here. 1512 * Caller must provide enough headroom on the packet to pull the short 1513 * header and append a long one. 1514 */ 1515 static int ltalk_rcv(struct sk_buff *skb, struct net_device *dev, 1516 struct packet_type *pt, struct net_device *orig_dev) 1517 { 1518 if (!net_eq(dev_net(dev), &init_net)) 1519 goto freeit; 1520 1521 /* Expand any short form frames */ 1522 if (skb_mac_header(skb)[2] == 1) { 1523 struct ddpehdr *ddp; 1524 /* Find our address */ 1525 struct atalk_addr *ap = atalk_find_dev_addr(dev); 1526 1527 if (!ap || skb->len < sizeof(__be16) || skb->len > 1023) 1528 goto freeit; 1529 1530 /* Don't mangle buffer if shared */ 1531 if (!(skb = skb_share_check(skb, GFP_ATOMIC))) 1532 return 0; 1533 1534 /* 1535 * The push leaves us with a ddephdr not an shdr, and 1536 * handily the port bytes in the right place preset. 1537 */ 1538 ddp = skb_push(skb, sizeof(*ddp) - 4); 1539 1540 /* Now fill in the long header */ 1541 1542 /* 1543 * These two first. The mac overlays the new source/dest 1544 * network information so we MUST copy these before 1545 * we write the network numbers ! 1546 */ 1547 1548 ddp->deh_dnode = skb_mac_header(skb)[0]; /* From physical header */ 1549 ddp->deh_snode = skb_mac_header(skb)[1]; /* From physical header */ 1550 1551 ddp->deh_dnet = ap->s_net; /* Network number */ 1552 ddp->deh_snet = ap->s_net; 1553 ddp->deh_sum = 0; /* No checksum */ 1554 /* 1555 * Not sure about this bit... 1556 */ 1557 /* Non routable, so force a drop if we slip up later */ 1558 ddp->deh_len_hops = htons(skb->len + (DDP_MAXHOPS << 10)); 1559 } 1560 skb_reset_transport_header(skb); 1561 1562 return atalk_rcv(skb, dev, pt, orig_dev); 1563 freeit: 1564 kfree_skb(skb); 1565 return 0; 1566 } 1567 1568 static int atalk_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) 1569 { 1570 struct sock *sk = sock->sk; 1571 struct atalk_sock *at = at_sk(sk); 1572 DECLARE_SOCKADDR(struct sockaddr_at *, usat, msg->msg_name); 1573 int flags = msg->msg_flags; 1574 int loopback = 0; 1575 struct sockaddr_at local_satalk, gsat; 1576 struct sk_buff *skb; 1577 struct net_device *dev; 1578 struct ddpehdr *ddp; 1579 int size; 1580 struct atalk_route *rt; 1581 int err; 1582 1583 if (flags & ~(MSG_DONTWAIT|MSG_CMSG_COMPAT)) 1584 return -EINVAL; 1585 1586 if (len > DDP_MAXSZ) 1587 return -EMSGSIZE; 1588 1589 lock_sock(sk); 1590 if (usat) { 1591 err = -EBUSY; 1592 if (sock_flag(sk, SOCK_ZAPPED)) 1593 if (atalk_autobind(sk) < 0) 1594 goto out; 1595 1596 err = -EINVAL; 1597 if (msg->msg_namelen < sizeof(*usat) || 1598 usat->sat_family != AF_APPLETALK) 1599 goto out; 1600 1601 err = -EPERM; 1602 /* netatalk didn't implement this check */ 1603 if (usat->sat_addr.s_node == ATADDR_BCAST && 1604 !sock_flag(sk, SOCK_BROADCAST)) { 1605 goto out; 1606 } 1607 } else { 1608 err = -ENOTCONN; 1609 if (sk->sk_state != TCP_ESTABLISHED) 1610 goto out; 1611 usat = &local_satalk; 1612 usat->sat_family = AF_APPLETALK; 1613 usat->sat_port = at->dest_port; 1614 usat->sat_addr.s_node = at->dest_node; 1615 usat->sat_addr.s_net = at->dest_net; 1616 } 1617 1618 /* Build a packet */ 1619 SOCK_DEBUG(sk, "SK %p: Got address.\n", sk); 1620 1621 /* For headers */ 1622 size = sizeof(struct ddpehdr) + len + ddp_dl->header_length; 1623 1624 if (usat->sat_addr.s_net || usat->sat_addr.s_node == ATADDR_ANYNODE) { 1625 rt = atrtr_find(&usat->sat_addr); 1626 } else { 1627 struct atalk_addr at_hint; 1628 1629 at_hint.s_node = 0; 1630 at_hint.s_net = at->src_net; 1631 1632 rt = atrtr_find(&at_hint); 1633 } 1634 err = -ENETUNREACH; 1635 if (!rt) 1636 goto out; 1637 1638 dev = rt->dev; 1639 1640 SOCK_DEBUG(sk, "SK %p: Size needed %d, device %s\n", 1641 sk, size, dev->name); 1642 1643 size += dev->hard_header_len; 1644 release_sock(sk); 1645 skb = sock_alloc_send_skb(sk, size, (flags & MSG_DONTWAIT), &err); 1646 lock_sock(sk); 1647 if (!skb) 1648 goto out; 1649 1650 skb_reserve(skb, ddp_dl->header_length); 1651 skb_reserve(skb, dev->hard_header_len); 1652 skb->dev = dev; 1653 1654 SOCK_DEBUG(sk, "SK %p: Begin build.\n", sk); 1655 1656 ddp = skb_put(skb, sizeof(struct ddpehdr)); 1657 ddp->deh_len_hops = htons(len + sizeof(*ddp)); 1658 ddp->deh_dnet = usat->sat_addr.s_net; 1659 ddp->deh_snet = at->src_net; 1660 ddp->deh_dnode = usat->sat_addr.s_node; 1661 ddp->deh_snode = at->src_node; 1662 ddp->deh_dport = usat->sat_port; 1663 ddp->deh_sport = at->src_port; 1664 1665 SOCK_DEBUG(sk, "SK %p: Copy user data (%zd bytes).\n", sk, len); 1666 1667 err = memcpy_from_msg(skb_put(skb, len), msg, len); 1668 if (err) { 1669 kfree_skb(skb); 1670 err = -EFAULT; 1671 goto out; 1672 } 1673 1674 if (sk->sk_no_check_tx) 1675 ddp->deh_sum = 0; 1676 else 1677 ddp->deh_sum = atalk_checksum(skb, len + sizeof(*ddp)); 1678 1679 /* 1680 * Loopback broadcast packets to non gateway targets (ie routes 1681 * to group we are in) 1682 */ 1683 if (ddp->deh_dnode == ATADDR_BCAST && 1684 !(rt->flags & RTF_GATEWAY) && !(dev->flags & IFF_LOOPBACK)) { 1685 struct sk_buff *skb2 = skb_copy(skb, GFP_KERNEL); 1686 1687 if (skb2) { 1688 loopback = 1; 1689 SOCK_DEBUG(sk, "SK %p: send out(copy).\n", sk); 1690 /* 1691 * If it fails it is queued/sent above in the aarp queue 1692 */ 1693 aarp_send_ddp(dev, skb2, &usat->sat_addr, NULL); 1694 } 1695 } 1696 1697 if (dev->flags & IFF_LOOPBACK || loopback) { 1698 SOCK_DEBUG(sk, "SK %p: Loop back.\n", sk); 1699 /* loop back */ 1700 skb_orphan(skb); 1701 if (ddp->deh_dnode == ATADDR_BCAST) { 1702 struct atalk_addr at_lo; 1703 1704 at_lo.s_node = 0; 1705 at_lo.s_net = 0; 1706 1707 rt = atrtr_find(&at_lo); 1708 if (!rt) { 1709 kfree_skb(skb); 1710 err = -ENETUNREACH; 1711 goto out; 1712 } 1713 dev = rt->dev; 1714 skb->dev = dev; 1715 } 1716 ddp_dl->request(ddp_dl, skb, dev->dev_addr); 1717 } else { 1718 SOCK_DEBUG(sk, "SK %p: send out.\n", sk); 1719 if (rt->flags & RTF_GATEWAY) { 1720 gsat.sat_addr = rt->gateway; 1721 usat = &gsat; 1722 } 1723 1724 /* 1725 * If it fails it is queued/sent above in the aarp queue 1726 */ 1727 aarp_send_ddp(dev, skb, &usat->sat_addr, NULL); 1728 } 1729 SOCK_DEBUG(sk, "SK %p: Done write (%zd).\n", sk, len); 1730 1731 out: 1732 release_sock(sk); 1733 return err ? : len; 1734 } 1735 1736 static int atalk_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1737 int flags) 1738 { 1739 struct sock *sk = sock->sk; 1740 struct ddpehdr *ddp; 1741 int copied = 0; 1742 int offset = 0; 1743 int err = 0; 1744 struct sk_buff *skb; 1745 1746 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, 1747 flags & MSG_DONTWAIT, &err); 1748 lock_sock(sk); 1749 1750 if (!skb) 1751 goto out; 1752 1753 /* FIXME: use skb->cb to be able to use shared skbs */ 1754 ddp = ddp_hdr(skb); 1755 copied = ntohs(ddp->deh_len_hops) & 1023; 1756 1757 if (sk->sk_type != SOCK_RAW) { 1758 offset = sizeof(*ddp); 1759 copied -= offset; 1760 } 1761 1762 if (copied > size) { 1763 copied = size; 1764 msg->msg_flags |= MSG_TRUNC; 1765 } 1766 err = skb_copy_datagram_msg(skb, offset, msg, copied); 1767 1768 if (!err && msg->msg_name) { 1769 DECLARE_SOCKADDR(struct sockaddr_at *, sat, msg->msg_name); 1770 sat->sat_family = AF_APPLETALK; 1771 sat->sat_port = ddp->deh_sport; 1772 sat->sat_addr.s_node = ddp->deh_snode; 1773 sat->sat_addr.s_net = ddp->deh_snet; 1774 msg->msg_namelen = sizeof(*sat); 1775 } 1776 1777 skb_free_datagram(sk, skb); /* Free the datagram. */ 1778 1779 out: 1780 release_sock(sk); 1781 return err ? : copied; 1782 } 1783 1784 1785 /* 1786 * AppleTalk ioctl calls. 1787 */ 1788 static int atalk_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 1789 { 1790 int rc = -ENOIOCTLCMD; 1791 struct sock *sk = sock->sk; 1792 void __user *argp = (void __user *)arg; 1793 1794 switch (cmd) { 1795 /* Protocol layer */ 1796 case TIOCOUTQ: { 1797 long amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk); 1798 1799 if (amount < 0) 1800 amount = 0; 1801 rc = put_user(amount, (int __user *)argp); 1802 break; 1803 } 1804 case TIOCINQ: { 1805 /* 1806 * These two are safe on a single CPU system as only 1807 * user tasks fiddle here 1808 */ 1809 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue); 1810 long amount = 0; 1811 1812 if (skb) 1813 amount = skb->len - sizeof(struct ddpehdr); 1814 rc = put_user(amount, (int __user *)argp); 1815 break; 1816 } 1817 /* Routing */ 1818 case SIOCADDRT: 1819 case SIOCDELRT: 1820 rc = -EPERM; 1821 if (capable(CAP_NET_ADMIN)) 1822 rc = atrtr_ioctl(cmd, argp); 1823 break; 1824 /* Interface */ 1825 case SIOCGIFADDR: 1826 case SIOCSIFADDR: 1827 case SIOCGIFBRDADDR: 1828 case SIOCATALKDIFADDR: 1829 case SIOCDIFADDR: 1830 case SIOCSARP: /* proxy AARP */ 1831 case SIOCDARP: /* proxy AARP */ 1832 rtnl_lock(); 1833 rc = atif_ioctl(cmd, argp); 1834 rtnl_unlock(); 1835 break; 1836 } 1837 1838 return rc; 1839 } 1840 1841 1842 #ifdef CONFIG_COMPAT 1843 static int atalk_compat_routing_ioctl(struct sock *sk, unsigned int cmd, 1844 struct compat_rtentry __user *ur) 1845 { 1846 compat_uptr_t rtdev; 1847 struct rtentry rt; 1848 1849 if (copy_from_user(&rt.rt_dst, &ur->rt_dst, 1850 3 * sizeof(struct sockaddr)) || 1851 get_user(rt.rt_flags, &ur->rt_flags) || 1852 get_user(rt.rt_metric, &ur->rt_metric) || 1853 get_user(rt.rt_mtu, &ur->rt_mtu) || 1854 get_user(rt.rt_window, &ur->rt_window) || 1855 get_user(rt.rt_irtt, &ur->rt_irtt) || 1856 get_user(rtdev, &ur->rt_dev)) 1857 return -EFAULT; 1858 1859 switch (cmd) { 1860 case SIOCDELRT: 1861 if (rt.rt_dst.sa_family != AF_APPLETALK) 1862 return -EINVAL; 1863 return atrtr_delete(&((struct sockaddr_at *) 1864 &rt.rt_dst)->sat_addr); 1865 1866 case SIOCADDRT: 1867 rt.rt_dev = compat_ptr(rtdev); 1868 return atrtr_ioctl_addrt(&rt); 1869 default: 1870 return -EINVAL; 1871 } 1872 } 1873 static int atalk_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 1874 { 1875 void __user *argp = compat_ptr(arg); 1876 struct sock *sk = sock->sk; 1877 1878 switch (cmd) { 1879 case SIOCADDRT: 1880 case SIOCDELRT: 1881 return atalk_compat_routing_ioctl(sk, cmd, argp); 1882 /* 1883 * SIOCATALKDIFADDR is a SIOCPROTOPRIVATE ioctl number, so we 1884 * cannot handle it in common code. The data we access if ifreq 1885 * here is compatible, so we can simply call the native 1886 * handler. 1887 */ 1888 case SIOCATALKDIFADDR: 1889 return atalk_ioctl(sock, cmd, (unsigned long)argp); 1890 default: 1891 return -ENOIOCTLCMD; 1892 } 1893 } 1894 #endif /* CONFIG_COMPAT */ 1895 1896 1897 static const struct net_proto_family atalk_family_ops = { 1898 .family = PF_APPLETALK, 1899 .create = atalk_create, 1900 .owner = THIS_MODULE, 1901 }; 1902 1903 static const struct proto_ops atalk_dgram_ops = { 1904 .family = PF_APPLETALK, 1905 .owner = THIS_MODULE, 1906 .release = atalk_release, 1907 .bind = atalk_bind, 1908 .connect = atalk_connect, 1909 .socketpair = sock_no_socketpair, 1910 .accept = sock_no_accept, 1911 .getname = atalk_getname, 1912 .poll = datagram_poll, 1913 .ioctl = atalk_ioctl, 1914 .gettstamp = sock_gettstamp, 1915 #ifdef CONFIG_COMPAT 1916 .compat_ioctl = atalk_compat_ioctl, 1917 #endif 1918 .listen = sock_no_listen, 1919 .shutdown = sock_no_shutdown, 1920 .setsockopt = sock_no_setsockopt, 1921 .getsockopt = sock_no_getsockopt, 1922 .sendmsg = atalk_sendmsg, 1923 .recvmsg = atalk_recvmsg, 1924 .mmap = sock_no_mmap, 1925 .sendpage = sock_no_sendpage, 1926 }; 1927 1928 static struct notifier_block ddp_notifier = { 1929 .notifier_call = ddp_device_event, 1930 }; 1931 1932 static struct packet_type ltalk_packet_type __read_mostly = { 1933 .type = cpu_to_be16(ETH_P_LOCALTALK), 1934 .func = ltalk_rcv, 1935 }; 1936 1937 static struct packet_type ppptalk_packet_type __read_mostly = { 1938 .type = cpu_to_be16(ETH_P_PPPTALK), 1939 .func = atalk_rcv, 1940 }; 1941 1942 static unsigned char ddp_snap_id[] = { 0x08, 0x00, 0x07, 0x80, 0x9B }; 1943 1944 /* Export symbols for use by drivers when AppleTalk is a module */ 1945 EXPORT_SYMBOL(atrtr_get_dev); 1946 EXPORT_SYMBOL(atalk_find_dev_addr); 1947 1948 /* Called by proto.c on kernel start up */ 1949 static int __init atalk_init(void) 1950 { 1951 int rc; 1952 1953 rc = proto_register(&ddp_proto, 0); 1954 if (rc) 1955 goto out; 1956 1957 rc = sock_register(&atalk_family_ops); 1958 if (rc) 1959 goto out_proto; 1960 1961 ddp_dl = register_snap_client(ddp_snap_id, atalk_rcv); 1962 if (!ddp_dl) { 1963 pr_crit("Unable to register DDP with SNAP.\n"); 1964 rc = -ENOMEM; 1965 goto out_sock; 1966 } 1967 1968 dev_add_pack(<alk_packet_type); 1969 dev_add_pack(&ppptalk_packet_type); 1970 1971 rc = register_netdevice_notifier(&ddp_notifier); 1972 if (rc) 1973 goto out_snap; 1974 1975 rc = aarp_proto_init(); 1976 if (rc) 1977 goto out_dev; 1978 1979 rc = atalk_proc_init(); 1980 if (rc) 1981 goto out_aarp; 1982 1983 rc = atalk_register_sysctl(); 1984 if (rc) 1985 goto out_proc; 1986 out: 1987 return rc; 1988 out_proc: 1989 atalk_proc_exit(); 1990 out_aarp: 1991 aarp_cleanup_module(); 1992 out_dev: 1993 unregister_netdevice_notifier(&ddp_notifier); 1994 out_snap: 1995 dev_remove_pack(&ppptalk_packet_type); 1996 dev_remove_pack(<alk_packet_type); 1997 unregister_snap_client(ddp_dl); 1998 out_sock: 1999 sock_unregister(PF_APPLETALK); 2000 out_proto: 2001 proto_unregister(&ddp_proto); 2002 goto out; 2003 } 2004 module_init(atalk_init); 2005 2006 /* 2007 * No explicit module reference count manipulation is needed in the 2008 * protocol. Socket layer sets module reference count for us 2009 * and interfaces reference counting is done 2010 * by the network device layer. 2011 * 2012 * Ergo, before the AppleTalk module can be removed, all AppleTalk 2013 * sockets be closed from user space. 2014 */ 2015 static void __exit atalk_exit(void) 2016 { 2017 #ifdef CONFIG_SYSCTL 2018 atalk_unregister_sysctl(); 2019 #endif /* CONFIG_SYSCTL */ 2020 atalk_proc_exit(); 2021 aarp_cleanup_module(); /* General aarp clean-up. */ 2022 unregister_netdevice_notifier(&ddp_notifier); 2023 dev_remove_pack(<alk_packet_type); 2024 dev_remove_pack(&ppptalk_packet_type); 2025 unregister_snap_client(ddp_dl); 2026 sock_unregister(PF_APPLETALK); 2027 proto_unregister(&ddp_proto); 2028 } 2029 module_exit(atalk_exit); 2030 2031 MODULE_LICENSE("GPL"); 2032 MODULE_AUTHOR("Alan Cox <alan@lxorguk.ukuu.org.uk>"); 2033 MODULE_DESCRIPTION("AppleTalk 0.20\n"); 2034 MODULE_ALIAS_NETPROTO(PF_APPLETALK); 2035