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