1/* 2 * af_llc.c - LLC User Interface SAPs 3 * Description: 4 * Functions in this module are implementation of socket based llc 5 * communications for the Linux operating system. Support of llc class 6 * one and class two is provided via SOCK_DGRAM and SOCK_STREAM 7 * respectively. 8 * 9 * An llc2 connection is (mac + sap), only one llc2 sap connection 10 * is allowed per mac. Though one sap may have multiple mac + sap 11 * connections. 12 * 13 * Copyright (c) 2001 by Jay Schulist <jschlst@samba.org> 14 * 2002-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br> 15 * 16 * This program can be redistributed or modified under the terms of the 17 * GNU General Public License as published by the Free Software Foundation. 18 * This program is distributed without any warranty or implied warranty 19 * of merchantability or fitness for a particular purpose. 20 * 21 * See the GNU General Public License for more details. 22 */ 23#include <linux/compiler.h> 24#include <linux/kernel.h> 25#include <linux/module.h> 26#include <linux/rtnetlink.h> 27#include <linux/init.h> 28#include <linux/slab.h> 29#include <net/llc.h> 30#include <net/llc_sap.h> 31#include <net/llc_pdu.h> 32#include <net/llc_conn.h> 33#include <net/tcp_states.h> 34 35/* remember: uninitialized global data is zeroed because its in .bss */ 36static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 37static u16 llc_ui_sap_link_no_max[256]; 38static struct sockaddr_llc llc_ui_addrnull; 39static const struct proto_ops llc_ui_ops; 40 41static int llc_ui_wait_for_conn(struct sock *sk, long timeout); 42static int llc_ui_wait_for_disc(struct sock *sk, long timeout); 43static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout); 44 45#define dprintk(args...) 46 47/* Maybe we'll add some more in the future. */ 48#define LLC_CMSG_PKTINFO 1 49 50 51/** 52 * llc_ui_next_link_no - return the next unused link number for a sap 53 * @sap: Address of sap to get link number from. 54 * 55 * Return the next unused link number for a given sap. 56 */ 57static inline u16 llc_ui_next_link_no(int sap) 58{ 59 return llc_ui_sap_link_no_max[sap]++; 60} 61 62/** 63 * llc_proto_type - return eth protocol for ARP header type 64 * @arphrd: ARP header type. 65 * 66 * Given an ARP header type return the corresponding ethernet protocol. 67 */ 68static inline __be16 llc_proto_type(u16 arphrd) 69{ 70 return arphrd == ARPHRD_IEEE802_TR ? 71 htons(ETH_P_TR_802_2) : htons(ETH_P_802_2); 72} 73 74/** 75 * llc_ui_addr_null - determines if a address structure is null 76 * @addr: Address to test if null. 77 */ 78static inline u8 llc_ui_addr_null(struct sockaddr_llc *addr) 79{ 80 return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr)); 81} 82 83/** 84 * llc_ui_header_len - return length of llc header based on operation 85 * @sk: Socket which contains a valid llc socket type. 86 * @addr: Complete sockaddr_llc structure received from the user. 87 * 88 * Provide the length of the llc header depending on what kind of 89 * operation the user would like to perform and the type of socket. 90 * Returns the correct llc header length. 91 */ 92static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr) 93{ 94 u8 rc = LLC_PDU_LEN_U; 95 96 if (addr->sllc_test || addr->sllc_xid) 97 rc = LLC_PDU_LEN_U; 98 else if (sk->sk_type == SOCK_STREAM) 99 rc = LLC_PDU_LEN_I; 100 return rc; 101} 102 103/** 104 * llc_ui_send_data - send data via reliable llc2 connection 105 * @sk: Connection the socket is using. 106 * @skb: Data the user wishes to send. 107 * @noblock: can we block waiting for data? 108 * 109 * Send data via reliable llc2 connection. 110 * Returns 0 upon success, non-zero if action did not succeed. 111 */ 112static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock) 113{ 114 struct llc_sock* llc = llc_sk(sk); 115 int rc = 0; 116 117 if (unlikely(llc_data_accept_state(llc->state) || 118 llc->remote_busy_flag || 119 llc->p_flag)) { 120 long timeout = sock_sndtimeo(sk, noblock); 121 122 rc = llc_ui_wait_for_busy_core(sk, timeout); 123 } 124 if (unlikely(!rc)) 125 rc = llc_build_and_send_pkt(sk, skb); 126 return rc; 127} 128 129static void llc_ui_sk_init(struct socket *sock, struct sock *sk) 130{ 131 sock_graft(sk, sock); 132 sk->sk_type = sock->type; 133 sock->ops = &llc_ui_ops; 134} 135 136static struct proto llc_proto = { 137 .name = "LLC", 138 .owner = THIS_MODULE, 139 .obj_size = sizeof(struct llc_sock), 140 .slab_flags = SLAB_DESTROY_BY_RCU, 141}; 142 143/** 144 * llc_ui_create - alloc and init a new llc_ui socket 145 * @net: network namespace (must be default network) 146 * @sock: Socket to initialize and attach allocated sk to. 147 * @protocol: Unused. 148 * @kern: on behalf of kernel or userspace 149 * 150 * Allocate and initialize a new llc_ui socket, validate the user wants a 151 * socket type we have available. 152 * Returns 0 upon success, negative upon failure. 153 */ 154static int llc_ui_create(struct net *net, struct socket *sock, int protocol, 155 int kern) 156{ 157 struct sock *sk; 158 int rc = -ESOCKTNOSUPPORT; 159 160 if (!capable(CAP_NET_RAW)) 161 return -EPERM; 162 163 if (!net_eq(net, &init_net)) 164 return -EAFNOSUPPORT; 165 166 if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) { 167 rc = -ENOMEM; 168 sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto); 169 if (sk) { 170 rc = 0; 171 llc_ui_sk_init(sock, sk); 172 } 173 } 174 return rc; 175} 176 177/** 178 * llc_ui_release - shutdown socket 179 * @sock: Socket to release. 180 * 181 * Shutdown and deallocate an existing socket. 182 */ 183static int llc_ui_release(struct socket *sock) 184{ 185 struct sock *sk = sock->sk; 186 struct llc_sock *llc; 187 188 if (unlikely(sk == NULL)) 189 goto out; 190 sock_hold(sk); 191 lock_sock(sk); 192 llc = llc_sk(sk); 193 dprintk("%s: closing local(%02X) remote(%02X)\n", __func__, 194 llc->laddr.lsap, llc->daddr.lsap); 195 if (!llc_send_disc(sk)) 196 llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo); 197 if (!sock_flag(sk, SOCK_ZAPPED)) 198 llc_sap_remove_socket(llc->sap, sk); 199 release_sock(sk); 200 if (llc->dev) 201 dev_put(llc->dev); 202 sock_put(sk); 203 llc_sk_free(sk); 204out: 205 return 0; 206} 207 208/** 209 * llc_ui_autoport - provide dynamically allocate SAP number 210 * 211 * Provide the caller with a dynamically allocated SAP number according 212 * to the rules that are set in this function. Returns: 0, upon failure, 213 * SAP number otherwise. 214 */ 215static int llc_ui_autoport(void) 216{ 217 struct llc_sap *sap; 218 int i, tries = 0; 219 220 while (tries < LLC_SAP_DYN_TRIES) { 221 for (i = llc_ui_sap_last_autoport; 222 i < LLC_SAP_DYN_STOP; i += 2) { 223 sap = llc_sap_find(i); 224 if (!sap) { 225 llc_ui_sap_last_autoport = i + 2; 226 goto out; 227 } 228 llc_sap_put(sap); 229 } 230 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 231 tries++; 232 } 233 i = 0; 234out: 235 return i; 236} 237 238/** 239 * llc_ui_autobind - automatically bind a socket to a sap 240 * @sock: socket to bind 241 * @addr: address to connect to 242 * 243 * Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't 244 * specifically used llc_ui_bind to bind to an specific address/sap 245 * 246 * Returns: 0 upon success, negative otherwise. 247 */ 248static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr) 249{ 250 struct sock *sk = sock->sk; 251 struct llc_sock *llc = llc_sk(sk); 252 struct llc_sap *sap; 253 int rc = -EINVAL; 254 255 if (!sock_flag(sk, SOCK_ZAPPED)) 256 goto out; 257 rc = -ENODEV; 258 if (sk->sk_bound_dev_if) { 259 llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if); 260 if (llc->dev && addr->sllc_arphrd != llc->dev->type) { 261 dev_put(llc->dev); 262 llc->dev = NULL; 263 } 264 } else 265 llc->dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd); 266 if (!llc->dev) 267 goto out; 268 rc = -EUSERS; 269 llc->laddr.lsap = llc_ui_autoport(); 270 if (!llc->laddr.lsap) 271 goto out; 272 rc = -EBUSY; /* some other network layer is using the sap */ 273 sap = llc_sap_open(llc->laddr.lsap, NULL); 274 if (!sap) 275 goto out; 276 memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN); 277 memcpy(&llc->addr, addr, sizeof(llc->addr)); 278 /* assign new connection to its SAP */ 279 llc_sap_add_socket(sap, sk); 280 sock_reset_flag(sk, SOCK_ZAPPED); 281 rc = 0; 282out: 283 return rc; 284} 285 286/** 287 * llc_ui_bind - bind a socket to a specific address. 288 * @sock: Socket to bind an address to. 289 * @uaddr: Address the user wants the socket bound to. 290 * @addrlen: Length of the uaddr structure. 291 * 292 * Bind a socket to a specific address. For llc a user is able to bind to 293 * a specific sap only or mac + sap. 294 * If the user desires to bind to a specific mac + sap, it is possible to 295 * have multiple sap connections via multiple macs. 296 * Bind and autobind for that matter must enforce the correct sap usage 297 * otherwise all hell will break loose. 298 * Returns: 0 upon success, negative otherwise. 299 */ 300static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen) 301{ 302 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr; 303 struct sock *sk = sock->sk; 304 struct llc_sock *llc = llc_sk(sk); 305 struct llc_sap *sap; 306 int rc = -EINVAL; 307 308 dprintk("%s: binding %02X\n", __func__, addr->sllc_sap); 309 if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr))) 310 goto out; 311 rc = -EAFNOSUPPORT; 312 if (unlikely(addr->sllc_family != AF_LLC)) 313 goto out; 314 rc = -ENODEV; 315 rtnl_lock(); 316 rcu_read_lock(); 317 if (sk->sk_bound_dev_if) { 318 llc->dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if); 319 if (llc->dev) { 320 if (!addr->sllc_arphrd) 321 addr->sllc_arphrd = llc->dev->type; 322 if (llc_mac_null(addr->sllc_mac)) 323 memcpy(addr->sllc_mac, llc->dev->dev_addr, 324 IFHWADDRLEN); 325 if (addr->sllc_arphrd != llc->dev->type || 326 !llc_mac_match(addr->sllc_mac, 327 llc->dev->dev_addr)) { 328 rc = -EINVAL; 329 llc->dev = NULL; 330 } 331 } 332 } else 333 llc->dev = dev_getbyhwaddr(&init_net, addr->sllc_arphrd, 334 addr->sllc_mac); 335 rcu_read_unlock(); 336 rtnl_unlock(); 337 if (!llc->dev) 338 goto out; 339 if (!addr->sllc_sap) { 340 rc = -EUSERS; 341 addr->sllc_sap = llc_ui_autoport(); 342 if (!addr->sllc_sap) 343 goto out; 344 } 345 sap = llc_sap_find(addr->sllc_sap); 346 if (!sap) { 347 sap = llc_sap_open(addr->sllc_sap, NULL); 348 rc = -EBUSY; /* some other network layer is using the sap */ 349 if (!sap) 350 goto out; 351 } else { 352 struct llc_addr laddr, daddr; 353 struct sock *ask; 354 355 memset(&laddr, 0, sizeof(laddr)); 356 memset(&daddr, 0, sizeof(daddr)); 357 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN); 358 laddr.lsap = addr->sllc_sap; 359 rc = -EADDRINUSE; /* mac + sap clash. */ 360 ask = llc_lookup_established(sap, &daddr, &laddr); 361 if (ask) { 362 sock_put(ask); 363 goto out_put; 364 } 365 } 366 llc->laddr.lsap = addr->sllc_sap; 367 memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN); 368 memcpy(&llc->addr, addr, sizeof(llc->addr)); 369 /* assign new connection to its SAP */ 370 llc_sap_add_socket(sap, sk); 371 sock_reset_flag(sk, SOCK_ZAPPED); 372 rc = 0; 373out_put: 374 llc_sap_put(sap); 375out: 376 return rc; 377} 378 379/** 380 * llc_ui_shutdown - shutdown a connect llc2 socket. 381 * @sock: Socket to shutdown. 382 * @how: What part of the socket to shutdown. 383 * 384 * Shutdown a connected llc2 socket. Currently this function only supports 385 * shutting down both sends and receives (2), we could probably make this 386 * function such that a user can shutdown only half the connection but not 387 * right now. 388 * Returns: 0 upon success, negative otherwise. 389 */ 390static int llc_ui_shutdown(struct socket *sock, int how) 391{ 392 struct sock *sk = sock->sk; 393 int rc = -ENOTCONN; 394 395 lock_sock(sk); 396 if (unlikely(sk->sk_state != TCP_ESTABLISHED)) 397 goto out; 398 rc = -EINVAL; 399 if (how != 2) 400 goto out; 401 rc = llc_send_disc(sk); 402 if (!rc) 403 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo); 404 /* Wake up anyone sleeping in poll */ 405 sk->sk_state_change(sk); 406out: 407 release_sock(sk); 408 return rc; 409} 410 411/** 412 * llc_ui_connect - Connect to a remote llc2 mac + sap. 413 * @sock: Socket which will be connected to the remote destination. 414 * @uaddr: Remote and possibly the local address of the new connection. 415 * @addrlen: Size of uaddr structure. 416 * @flags: Operational flags specified by the user. 417 * 418 * Connect to a remote llc2 mac + sap. The caller must specify the 419 * destination mac and address to connect to. If the user hasn't previously 420 * called bind(2) with a smac the address of the first interface of the 421 * specified arp type will be used. 422 * This function will autobind if user did not previously call bind. 423 * Returns: 0 upon success, negative otherwise. 424 */ 425static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr, 426 int addrlen, int flags) 427{ 428 struct sock *sk = sock->sk; 429 struct llc_sock *llc = llc_sk(sk); 430 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr; 431 int rc = -EINVAL; 432 433 lock_sock(sk); 434 if (unlikely(addrlen != sizeof(*addr))) 435 goto out; 436 rc = -EAFNOSUPPORT; 437 if (unlikely(addr->sllc_family != AF_LLC)) 438 goto out; 439 if (unlikely(sk->sk_type != SOCK_STREAM)) 440 goto out; 441 rc = -EALREADY; 442 if (unlikely(sock->state == SS_CONNECTING)) 443 goto out; 444 /* bind connection to sap if user hasn't done it. */ 445 if (sock_flag(sk, SOCK_ZAPPED)) { 446 /* bind to sap with null dev, exclusive */ 447 rc = llc_ui_autobind(sock, addr); 448 if (rc) 449 goto out; 450 } 451 llc->daddr.lsap = addr->sllc_sap; 452 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN); 453 sock->state = SS_CONNECTING; 454 sk->sk_state = TCP_SYN_SENT; 455 llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap); 456 rc = llc_establish_connection(sk, llc->dev->dev_addr, 457 addr->sllc_mac, addr->sllc_sap); 458 if (rc) { 459 dprintk("%s: llc_ui_send_conn failed :-(\n", __func__); 460 sock->state = SS_UNCONNECTED; 461 sk->sk_state = TCP_CLOSE; 462 goto out; 463 } 464 465 if (sk->sk_state == TCP_SYN_SENT) { 466 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); 467 468 if (!timeo || !llc_ui_wait_for_conn(sk, timeo)) 469 goto out; 470 471 rc = sock_intr_errno(timeo); 472 if (signal_pending(current)) 473 goto out; 474 } 475 476 if (sk->sk_state == TCP_CLOSE) 477 goto sock_error; 478 479 sock->state = SS_CONNECTED; 480 rc = 0; 481out: 482 release_sock(sk); 483 return rc; 484sock_error: 485 rc = sock_error(sk) ? : -ECONNABORTED; 486 sock->state = SS_UNCONNECTED; 487 goto out; 488} 489 490/** 491 * llc_ui_listen - allow a normal socket to accept incoming connections 492 * @sock: Socket to allow incoming connections on. 493 * @backlog: Number of connections to queue. 494 * 495 * Allow a normal socket to accept incoming connections. 496 * Returns 0 upon success, negative otherwise. 497 */ 498static int llc_ui_listen(struct socket *sock, int backlog) 499{ 500 struct sock *sk = sock->sk; 501 int rc = -EINVAL; 502 503 lock_sock(sk); 504 if (unlikely(sock->state != SS_UNCONNECTED)) 505 goto out; 506 rc = -EOPNOTSUPP; 507 if (unlikely(sk->sk_type != SOCK_STREAM)) 508 goto out; 509 rc = -EAGAIN; 510 if (sock_flag(sk, SOCK_ZAPPED)) 511 goto out; 512 rc = 0; 513 if (!(unsigned)backlog) /* BSDism */ 514 backlog = 1; 515 sk->sk_max_ack_backlog = backlog; 516 if (sk->sk_state != TCP_LISTEN) { 517 sk->sk_ack_backlog = 0; 518 sk->sk_state = TCP_LISTEN; 519 } 520 sk->sk_socket->flags |= __SO_ACCEPTCON; 521out: 522 release_sock(sk); 523 return rc; 524} 525 526static int llc_ui_wait_for_disc(struct sock *sk, long timeout) 527{ 528 DEFINE_WAIT(wait); 529 int rc = 0; 530 531 while (1) { 532 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 533 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE)) 534 break; 535 rc = -ERESTARTSYS; 536 if (signal_pending(current)) 537 break; 538 rc = -EAGAIN; 539 if (!timeout) 540 break; 541 rc = 0; 542 } 543 finish_wait(sk_sleep(sk), &wait); 544 return rc; 545} 546 547static int llc_ui_wait_for_conn(struct sock *sk, long timeout) 548{ 549 DEFINE_WAIT(wait); 550 551 while (1) { 552 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 553 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT)) 554 break; 555 if (signal_pending(current) || !timeout) 556 break; 557 } 558 finish_wait(sk_sleep(sk), &wait); 559 return timeout; 560} 561 562static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout) 563{ 564 DEFINE_WAIT(wait); 565 struct llc_sock *llc = llc_sk(sk); 566 int rc; 567 568 while (1) { 569 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 570 rc = 0; 571 if (sk_wait_event(sk, &timeout, 572 (sk->sk_shutdown & RCV_SHUTDOWN) || 573 (!llc_data_accept_state(llc->state) && 574 !llc->remote_busy_flag && 575 !llc->p_flag))) 576 break; 577 rc = -ERESTARTSYS; 578 if (signal_pending(current)) 579 break; 580 rc = -EAGAIN; 581 if (!timeout) 582 break; 583 } 584 finish_wait(sk_sleep(sk), &wait); 585 return rc; 586} 587 588static int llc_wait_data(struct sock *sk, long timeo) 589{ 590 int rc; 591 592 while (1) { 593 /* 594 * POSIX 1003.1g mandates this order. 595 */ 596 rc = sock_error(sk); 597 if (rc) 598 break; 599 rc = 0; 600 if (sk->sk_shutdown & RCV_SHUTDOWN) 601 break; 602 rc = -EAGAIN; 603 if (!timeo) 604 break; 605 rc = sock_intr_errno(timeo); 606 if (signal_pending(current)) 607 break; 608 rc = 0; 609 if (sk_wait_data(sk, &timeo)) 610 break; 611 } 612 return rc; 613} 614 615static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb) 616{ 617 struct llc_sock *llc = llc_sk(skb->sk); 618 619 if (llc->cmsg_flags & LLC_CMSG_PKTINFO) { 620 struct llc_pktinfo info; 621 622 info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex; 623 llc_pdu_decode_dsap(skb, &info.lpi_sap); 624 llc_pdu_decode_da(skb, info.lpi_mac); 625 put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info); 626 } 627} 628 629/** 630 * llc_ui_accept - accept a new incoming connection. 631 * @sock: Socket which connections arrive on. 632 * @newsock: Socket to move incoming connection to. 633 * @flags: User specified operational flags. 634 * 635 * Accept a new incoming connection. 636 * Returns 0 upon success, negative otherwise. 637 */ 638static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags) 639{ 640 struct sock *sk = sock->sk, *newsk; 641 struct llc_sock *llc, *newllc; 642 struct sk_buff *skb; 643 int rc = -EOPNOTSUPP; 644 645 dprintk("%s: accepting on %02X\n", __func__, 646 llc_sk(sk)->laddr.lsap); 647 lock_sock(sk); 648 if (unlikely(sk->sk_type != SOCK_STREAM)) 649 goto out; 650 rc = -EINVAL; 651 if (unlikely(sock->state != SS_UNCONNECTED || 652 sk->sk_state != TCP_LISTEN)) 653 goto out; 654 /* wait for a connection to arrive. */ 655 if (skb_queue_empty(&sk->sk_receive_queue)) { 656 rc = llc_wait_data(sk, sk->sk_rcvtimeo); 657 if (rc) 658 goto out; 659 } 660 dprintk("%s: got a new connection on %02X\n", __func__, 661 llc_sk(sk)->laddr.lsap); 662 skb = skb_dequeue(&sk->sk_receive_queue); 663 rc = -EINVAL; 664 if (!skb->sk) 665 goto frees; 666 rc = 0; 667 newsk = skb->sk; 668 /* attach connection to a new socket. */ 669 llc_ui_sk_init(newsock, newsk); 670 sock_reset_flag(newsk, SOCK_ZAPPED); 671 newsk->sk_state = TCP_ESTABLISHED; 672 newsock->state = SS_CONNECTED; 673 llc = llc_sk(sk); 674 newllc = llc_sk(newsk); 675 memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr)); 676 newllc->link = llc_ui_next_link_no(newllc->laddr.lsap); 677 678 /* put original socket back into a clean listen state. */ 679 sk->sk_state = TCP_LISTEN; 680 sk->sk_ack_backlog--; 681 dprintk("%s: ok success on %02X, client on %02X\n", __func__, 682 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap); 683frees: 684 kfree_skb(skb); 685out: 686 release_sock(sk); 687 return rc; 688} 689 690/** 691 * llc_ui_recvmsg - copy received data to the socket user. 692 * @sock: Socket to copy data from. 693 * @msg: Various user space related information. 694 * @len: Size of user buffer. 695 * @flags: User specified flags. 696 * 697 * Copy received data to the socket user. 698 * Returns non-negative upon success, negative otherwise. 699 */ 700static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock, 701 struct msghdr *msg, size_t len, int flags) 702{ 703 struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name; 704 const int nonblock = flags & MSG_DONTWAIT; 705 struct sk_buff *skb = NULL; 706 struct sock *sk = sock->sk; 707 struct llc_sock *llc = llc_sk(sk); 708 size_t copied = 0; 709 u32 peek_seq = 0; 710 u32 *seq; 711 unsigned long used; 712 int target; /* Read at least this many bytes */ 713 long timeo; 714 715 lock_sock(sk); 716 copied = -ENOTCONN; 717 if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN)) 718 goto out; 719 720 timeo = sock_rcvtimeo(sk, nonblock); 721 722 seq = &llc->copied_seq; 723 if (flags & MSG_PEEK) { 724 peek_seq = llc->copied_seq; 725 seq = &peek_seq; 726 } 727 728 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 729 copied = 0; 730 731 do { 732 u32 offset; 733 734 if (signal_pending(current)) { 735 if (copied) 736 break; 737 copied = timeo ? sock_intr_errno(timeo) : -EAGAIN; 738 break; 739 } 740 741 /* Next get a buffer. */ 742 743 skb = skb_peek(&sk->sk_receive_queue); 744 if (skb) { 745 offset = *seq; 746 goto found_ok_skb; 747 } 748 /* Well, if we have backlog, try to process it now yet. */ 749 750 if (copied >= target && !sk->sk_backlog.tail) 751 break; 752 753 if (copied) { 754 if (sk->sk_err || 755 sk->sk_state == TCP_CLOSE || 756 (sk->sk_shutdown & RCV_SHUTDOWN) || 757 !timeo || 758 (flags & MSG_PEEK)) 759 break; 760 } else { 761 if (sock_flag(sk, SOCK_DONE)) 762 break; 763 764 if (sk->sk_err) { 765 copied = sock_error(sk); 766 break; 767 } 768 if (sk->sk_shutdown & RCV_SHUTDOWN) 769 break; 770 771 if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) { 772 if (!sock_flag(sk, SOCK_DONE)) { 773 /* 774 * This occurs when user tries to read 775 * from never connected socket. 776 */ 777 copied = -ENOTCONN; 778 break; 779 } 780 break; 781 } 782 if (!timeo) { 783 copied = -EAGAIN; 784 break; 785 } 786 } 787 788 if (copied >= target) { /* Do not sleep, just process backlog. */ 789 release_sock(sk); 790 lock_sock(sk); 791 } else 792 sk_wait_data(sk, &timeo); 793 794 if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) { 795 if (net_ratelimit()) 796 printk(KERN_DEBUG "LLC(%s:%d): Application " 797 "bug, race in MSG_PEEK.\n", 798 current->comm, task_pid_nr(current)); 799 peek_seq = llc->copied_seq; 800 } 801 continue; 802 found_ok_skb: 803 /* Ok so how much can we use? */ 804 used = skb->len - offset; 805 if (len < used) 806 used = len; 807 808 if (!(flags & MSG_TRUNC)) { 809 int rc = skb_copy_datagram_iovec(skb, offset, 810 msg->msg_iov, used); 811 if (rc) { 812 /* Exception. Bailout! */ 813 if (!copied) 814 copied = -EFAULT; 815 break; 816 } 817 } 818 819 *seq += used; 820 copied += used; 821 len -= used; 822 823 if (!(flags & MSG_PEEK)) { 824 sk_eat_skb(sk, skb, 0); 825 *seq = 0; 826 } 827 828 /* For non stream protcols we get one packet per recvmsg call */ 829 if (sk->sk_type != SOCK_STREAM) 830 goto copy_uaddr; 831 832 /* Partial read */ 833 if (used + offset < skb->len) 834 continue; 835 } while (len > 0); 836 837out: 838 release_sock(sk); 839 return copied; 840copy_uaddr: 841 if (uaddr != NULL && skb != NULL) { 842 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr)); 843 msg->msg_namelen = sizeof(*uaddr); 844 } 845 if (llc_sk(sk)->cmsg_flags) 846 llc_cmsg_rcv(msg, skb); 847 goto out; 848} 849 850/** 851 * llc_ui_sendmsg - Transmit data provided by the socket user. 852 * @sock: Socket to transmit data from. 853 * @msg: Various user related information. 854 * @len: Length of data to transmit. 855 * 856 * Transmit data provided by the socket user. 857 * Returns non-negative upon success, negative otherwise. 858 */ 859static int llc_ui_sendmsg(struct kiocb *iocb, struct socket *sock, 860 struct msghdr *msg, size_t len) 861{ 862 struct sock *sk = sock->sk; 863 struct llc_sock *llc = llc_sk(sk); 864 struct sockaddr_llc *addr = (struct sockaddr_llc *)msg->msg_name; 865 int flags = msg->msg_flags; 866 int noblock = flags & MSG_DONTWAIT; 867 struct sk_buff *skb; 868 size_t size = 0; 869 int rc = -EINVAL, copied = 0, hdrlen; 870 871 dprintk("%s: sending from %02X to %02X\n", __func__, 872 llc->laddr.lsap, llc->daddr.lsap); 873 lock_sock(sk); 874 if (addr) { 875 if (msg->msg_namelen < sizeof(*addr)) 876 goto release; 877 } else { 878 if (llc_ui_addr_null(&llc->addr)) 879 goto release; 880 addr = &llc->addr; 881 } 882 /* must bind connection to sap if user hasn't done it. */ 883 if (sock_flag(sk, SOCK_ZAPPED)) { 884 /* bind to sap with null dev, exclusive. */ 885 rc = llc_ui_autobind(sock, addr); 886 if (rc) 887 goto release; 888 } 889 hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr); 890 size = hdrlen + len; 891 if (size > llc->dev->mtu) 892 size = llc->dev->mtu; 893 copied = size - hdrlen; 894 release_sock(sk); 895 skb = sock_alloc_send_skb(sk, size, noblock, &rc); 896 lock_sock(sk); 897 if (!skb) 898 goto release; 899 skb->dev = llc->dev; 900 skb->protocol = llc_proto_type(addr->sllc_arphrd); 901 skb_reserve(skb, hdrlen); 902 rc = memcpy_fromiovec(skb_put(skb, copied), msg->msg_iov, copied); 903 if (rc) 904 goto out; 905 if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) { 906 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac, 907 addr->sllc_sap); 908 goto out; 909 } 910 if (addr->sllc_test) { 911 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac, 912 addr->sllc_sap); 913 goto out; 914 } 915 if (addr->sllc_xid) { 916 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac, 917 addr->sllc_sap); 918 goto out; 919 } 920 rc = -ENOPROTOOPT; 921 if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua)) 922 goto out; 923 rc = llc_ui_send_data(sk, skb, noblock); 924out: 925 if (rc) { 926 kfree_skb(skb); 927release: 928 dprintk("%s: failed sending from %02X to %02X: %d\n", 929 __func__, llc->laddr.lsap, llc->daddr.lsap, rc); 930 } 931 release_sock(sk); 932 return rc ? : copied; 933} 934 935/** 936 * llc_ui_getname - return the address info of a socket 937 * @sock: Socket to get address of. 938 * @uaddr: Address structure to return information. 939 * @uaddrlen: Length of address structure. 940 * @peer: Does user want local or remote address information. 941 * 942 * Return the address information of a socket. 943 */ 944static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr, 945 int *uaddrlen, int peer) 946{ 947 struct sockaddr_llc sllc; 948 struct sock *sk = sock->sk; 949 struct llc_sock *llc = llc_sk(sk); 950 int rc = 0; 951 952 memset(&sllc, 0, sizeof(sllc)); 953 lock_sock(sk); 954 if (sock_flag(sk, SOCK_ZAPPED)) 955 goto out; 956 *uaddrlen = sizeof(sllc); 957 memset(uaddr, 0, *uaddrlen); 958 if (peer) { 959 rc = -ENOTCONN; 960 if (sk->sk_state != TCP_ESTABLISHED) 961 goto out; 962 if(llc->dev) 963 sllc.sllc_arphrd = llc->dev->type; 964 sllc.sllc_sap = llc->daddr.lsap; 965 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN); 966 } else { 967 rc = -EINVAL; 968 if (!llc->sap) 969 goto out; 970 sllc.sllc_sap = llc->sap->laddr.lsap; 971 972 if (llc->dev) { 973 sllc.sllc_arphrd = llc->dev->type; 974 memcpy(&sllc.sllc_mac, llc->dev->dev_addr, 975 IFHWADDRLEN); 976 } 977 } 978 rc = 0; 979 sllc.sllc_family = AF_LLC; 980 memcpy(uaddr, &sllc, sizeof(sllc)); 981out: 982 release_sock(sk); 983 return rc; 984} 985 986/** 987 * llc_ui_ioctl - io controls for PF_LLC 988 * @sock: Socket to get/set info 989 * @cmd: command 990 * @arg: optional argument for cmd 991 * 992 * get/set info on llc sockets 993 */ 994static int llc_ui_ioctl(struct socket *sock, unsigned int cmd, 995 unsigned long arg) 996{ 997 return -ENOIOCTLCMD; 998} 999 1000/** 1001 * llc_ui_setsockopt - set various connection specific parameters. 1002 * @sock: Socket to set options on. 1003 * @level: Socket level user is requesting operations on. 1004 * @optname: Operation name. 1005 * @optval User provided operation data. 1006 * @optlen: Length of optval. 1007 * 1008 * Set various connection specific parameters. 1009 */ 1010static int llc_ui_setsockopt(struct socket *sock, int level, int optname, 1011 char __user *optval, unsigned int optlen) 1012{ 1013 struct sock *sk = sock->sk; 1014 struct llc_sock *llc = llc_sk(sk); 1015 unsigned int opt; 1016 int rc = -EINVAL; 1017 1018 lock_sock(sk); 1019 if (unlikely(level != SOL_LLC || optlen != sizeof(int))) 1020 goto out; 1021 rc = get_user(opt, (int __user *)optval); 1022 if (rc) 1023 goto out; 1024 rc = -EINVAL; 1025 switch (optname) { 1026 case LLC_OPT_RETRY: 1027 if (opt > LLC_OPT_MAX_RETRY) 1028 goto out; 1029 llc->n2 = opt; 1030 break; 1031 case LLC_OPT_SIZE: 1032 if (opt > LLC_OPT_MAX_SIZE) 1033 goto out; 1034 llc->n1 = opt; 1035 break; 1036 case LLC_OPT_ACK_TMR_EXP: 1037 if (opt > LLC_OPT_MAX_ACK_TMR_EXP) 1038 goto out; 1039 llc->ack_timer.expire = opt * HZ; 1040 break; 1041 case LLC_OPT_P_TMR_EXP: 1042 if (opt > LLC_OPT_MAX_P_TMR_EXP) 1043 goto out; 1044 llc->pf_cycle_timer.expire = opt * HZ; 1045 break; 1046 case LLC_OPT_REJ_TMR_EXP: 1047 if (opt > LLC_OPT_MAX_REJ_TMR_EXP) 1048 goto out; 1049 llc->rej_sent_timer.expire = opt * HZ; 1050 break; 1051 case LLC_OPT_BUSY_TMR_EXP: 1052 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP) 1053 goto out; 1054 llc->busy_state_timer.expire = opt * HZ; 1055 break; 1056 case LLC_OPT_TX_WIN: 1057 if (opt > LLC_OPT_MAX_WIN) 1058 goto out; 1059 llc->k = opt; 1060 break; 1061 case LLC_OPT_RX_WIN: 1062 if (opt > LLC_OPT_MAX_WIN) 1063 goto out; 1064 llc->rw = opt; 1065 break; 1066 case LLC_OPT_PKTINFO: 1067 if (opt) 1068 llc->cmsg_flags |= LLC_CMSG_PKTINFO; 1069 else 1070 llc->cmsg_flags &= ~LLC_CMSG_PKTINFO; 1071 break; 1072 default: 1073 rc = -ENOPROTOOPT; 1074 goto out; 1075 } 1076 rc = 0; 1077out: 1078 release_sock(sk); 1079 return rc; 1080} 1081 1082/** 1083 * llc_ui_getsockopt - get connection specific socket info 1084 * @sock: Socket to get information from. 1085 * @level: Socket level user is requesting operations on. 1086 * @optname: Operation name. 1087 * @optval: Variable to return operation data in. 1088 * @optlen: Length of optval. 1089 * 1090 * Get connection specific socket information. 1091 */ 1092static int llc_ui_getsockopt(struct socket *sock, int level, int optname, 1093 char __user *optval, int __user *optlen) 1094{ 1095 struct sock *sk = sock->sk; 1096 struct llc_sock *llc = llc_sk(sk); 1097 int val = 0, len = 0, rc = -EINVAL; 1098 1099 lock_sock(sk); 1100 if (unlikely(level != SOL_LLC)) 1101 goto out; 1102 rc = get_user(len, optlen); 1103 if (rc) 1104 goto out; 1105 rc = -EINVAL; 1106 if (len != sizeof(int)) 1107 goto out; 1108 switch (optname) { 1109 case LLC_OPT_RETRY: 1110 val = llc->n2; break; 1111 case LLC_OPT_SIZE: 1112 val = llc->n1; break; 1113 case LLC_OPT_ACK_TMR_EXP: 1114 val = llc->ack_timer.expire / HZ; break; 1115 case LLC_OPT_P_TMR_EXP: 1116 val = llc->pf_cycle_timer.expire / HZ; break; 1117 case LLC_OPT_REJ_TMR_EXP: 1118 val = llc->rej_sent_timer.expire / HZ; break; 1119 case LLC_OPT_BUSY_TMR_EXP: 1120 val = llc->busy_state_timer.expire / HZ; break; 1121 case LLC_OPT_TX_WIN: 1122 val = llc->k; break; 1123 case LLC_OPT_RX_WIN: 1124 val = llc->rw; break; 1125 case LLC_OPT_PKTINFO: 1126 val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0; 1127 break; 1128 default: 1129 rc = -ENOPROTOOPT; 1130 goto out; 1131 } 1132 rc = 0; 1133 if (put_user(len, optlen) || copy_to_user(optval, &val, len)) 1134 rc = -EFAULT; 1135out: 1136 release_sock(sk); 1137 return rc; 1138} 1139 1140static const struct net_proto_family llc_ui_family_ops = { 1141 .family = PF_LLC, 1142 .create = llc_ui_create, 1143 .owner = THIS_MODULE, 1144}; 1145 1146static const struct proto_ops llc_ui_ops = { 1147 .family = PF_LLC, 1148 .owner = THIS_MODULE, 1149 .release = llc_ui_release, 1150 .bind = llc_ui_bind, 1151 .connect = llc_ui_connect, 1152 .socketpair = sock_no_socketpair, 1153 .accept = llc_ui_accept, 1154 .getname = llc_ui_getname, 1155 .poll = datagram_poll, 1156 .ioctl = llc_ui_ioctl, 1157 .listen = llc_ui_listen, 1158 .shutdown = llc_ui_shutdown, 1159 .setsockopt = llc_ui_setsockopt, 1160 .getsockopt = llc_ui_getsockopt, 1161 .sendmsg = llc_ui_sendmsg, 1162 .recvmsg = llc_ui_recvmsg, 1163 .mmap = sock_no_mmap, 1164 .sendpage = sock_no_sendpage, 1165}; 1166 1167static const char llc_proc_err_msg[] __initconst = 1168 KERN_CRIT "LLC: Unable to register the proc_fs entries\n"; 1169static const char llc_sysctl_err_msg[] __initconst = 1170 KERN_CRIT "LLC: Unable to register the sysctl entries\n"; 1171static const char llc_sock_err_msg[] __initconst = 1172 KERN_CRIT "LLC: Unable to register the network family\n"; 1173 1174static int __init llc2_init(void) 1175{ 1176 int rc = proto_register(&llc_proto, 0); 1177 1178 if (rc != 0) 1179 goto out; 1180 1181 llc_build_offset_table(); 1182 llc_station_init(); 1183 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 1184 rc = llc_proc_init(); 1185 if (rc != 0) { 1186 printk(llc_proc_err_msg); 1187 goto out_unregister_llc_proto; 1188 } 1189 rc = llc_sysctl_init(); 1190 if (rc) { 1191 printk(llc_sysctl_err_msg); 1192 goto out_proc; 1193 } 1194 rc = sock_register(&llc_ui_family_ops); 1195 if (rc) { 1196 printk(llc_sock_err_msg); 1197 goto out_sysctl; 1198 } 1199 llc_add_pack(LLC_DEST_SAP, llc_sap_handler); 1200 llc_add_pack(LLC_DEST_CONN, llc_conn_handler); 1201out: 1202 return rc; 1203out_sysctl: 1204 llc_sysctl_exit(); 1205out_proc: 1206 llc_proc_exit(); 1207out_unregister_llc_proto: 1208 proto_unregister(&llc_proto); 1209 goto out; 1210} 1211 1212static void __exit llc2_exit(void) 1213{ 1214 llc_station_exit(); 1215 llc_remove_pack(LLC_DEST_SAP); 1216 llc_remove_pack(LLC_DEST_CONN); 1217 sock_unregister(PF_LLC); 1218 llc_proc_exit(); 1219 llc_sysctl_exit(); 1220 proto_unregister(&llc_proto); 1221} 1222 1223module_init(llc2_init); 1224module_exit(llc2_exit); 1225 1226MODULE_LICENSE("GPL"); 1227MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003"); 1228MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support"); 1229MODULE_ALIAS_NETPROTO(PF_LLC); 1230