af_llc.c revision b76f5a8427ac2928c07fa4ff2144bb8db072c240
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 <net/llc.h> 29#include <net/llc_sap.h> 30#include <net/llc_pdu.h> 31#include <net/llc_conn.h> 32#include <net/tcp_states.h> 33 34/* remember: uninitialized global data is zeroed because its in .bss */ 35static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 36static u16 llc_ui_sap_link_no_max[256]; 37static struct sockaddr_llc llc_ui_addrnull; 38static const struct proto_ops llc_ui_ops; 39 40static int llc_ui_wait_for_conn(struct sock *sk, long timeout); 41static int llc_ui_wait_for_disc(struct sock *sk, long timeout); 42static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout); 43 44#if 0 45#define dprintk(args...) printk(KERN_DEBUG args) 46#else 47#define dprintk(args...) 48#endif 49 50/* Maybe we'll add some more in the future. */ 51#define LLC_CMSG_PKTINFO 1 52 53 54/** 55 * llc_ui_next_link_no - return the next unused link number for a sap 56 * @sap: Address of sap to get link number from. 57 * 58 * Return the next unused link number for a given sap. 59 */ 60static inline u16 llc_ui_next_link_no(int sap) 61{ 62 return llc_ui_sap_link_no_max[sap]++; 63} 64 65/** 66 * llc_proto_type - return eth protocol for ARP header type 67 * @arphrd: ARP header type. 68 * 69 * Given an ARP header type return the corresponding ethernet protocol. 70 */ 71static inline __be16 llc_proto_type(u16 arphrd) 72{ 73 return arphrd == ARPHRD_IEEE802_TR ? 74 htons(ETH_P_TR_802_2) : htons(ETH_P_802_2); 75} 76 77/** 78 * llc_ui_addr_null - determines if a address structure is null 79 * @addr: Address to test if null. 80 */ 81static inline u8 llc_ui_addr_null(struct sockaddr_llc *addr) 82{ 83 return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr)); 84} 85 86/** 87 * llc_ui_header_len - return length of llc header based on operation 88 * @sk: Socket which contains a valid llc socket type. 89 * @addr: Complete sockaddr_llc structure received from the user. 90 * 91 * Provide the length of the llc header depending on what kind of 92 * operation the user would like to perform and the type of socket. 93 * Returns the correct llc header length. 94 */ 95static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr) 96{ 97 u8 rc = LLC_PDU_LEN_U; 98 99 if (addr->sllc_test || addr->sllc_xid) 100 rc = LLC_PDU_LEN_U; 101 else if (sk->sk_type == SOCK_STREAM) 102 rc = LLC_PDU_LEN_I; 103 return rc; 104} 105 106/** 107 * llc_ui_send_data - send data via reliable llc2 connection 108 * @sk: Connection the socket is using. 109 * @skb: Data the user wishes to send. 110 * @noblock: can we block waiting for data? 111 * 112 * Send data via reliable llc2 connection. 113 * Returns 0 upon success, non-zero if action did not succeed. 114 */ 115static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock) 116{ 117 struct llc_sock* llc = llc_sk(sk); 118 int rc = 0; 119 120 if (unlikely(llc_data_accept_state(llc->state) || 121 llc->remote_busy_flag || 122 llc->p_flag)) { 123 long timeout = sock_sndtimeo(sk, noblock); 124 125 rc = llc_ui_wait_for_busy_core(sk, timeout); 126 } 127 if (unlikely(!rc)) 128 rc = llc_build_and_send_pkt(sk, skb); 129 return rc; 130} 131 132static void llc_ui_sk_init(struct socket *sock, struct sock *sk) 133{ 134 sock_graft(sk, sock); 135 sk->sk_type = sock->type; 136 sock->ops = &llc_ui_ops; 137} 138 139static struct proto llc_proto = { 140 .name = "LLC", 141 .owner = THIS_MODULE, 142 .obj_size = sizeof(struct llc_sock), 143 .slab_flags = SLAB_DESTROY_BY_RCU, 144}; 145 146/** 147 * llc_ui_create - alloc and init a new llc_ui socket 148 * @net: network namespace (must be default network) 149 * @sock: Socket to initialize and attach allocated sk to. 150 * @protocol: Unused. 151 * @kern: on behalf of kernel or userspace 152 * 153 * Allocate and initialize a new llc_ui socket, validate the user wants a 154 * socket type we have available. 155 * Returns 0 upon success, negative upon failure. 156 */ 157static int llc_ui_create(struct net *net, struct socket *sock, int protocol, 158 int kern) 159{ 160 struct sock *sk; 161 int rc = -ESOCKTNOSUPPORT; 162 163 if (!capable(CAP_NET_RAW)) 164 return -EPERM; 165 166 if (!net_eq(net, &init_net)) 167 return -EAFNOSUPPORT; 168 169 if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) { 170 rc = -ENOMEM; 171 sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto); 172 if (sk) { 173 rc = 0; 174 llc_ui_sk_init(sock, sk); 175 } 176 } 177 return rc; 178} 179 180/** 181 * llc_ui_release - shutdown socket 182 * @sock: Socket to release. 183 * 184 * Shutdown and deallocate an existing socket. 185 */ 186static int llc_ui_release(struct socket *sock) 187{ 188 struct sock *sk = sock->sk; 189 struct llc_sock *llc; 190 191 if (unlikely(sk == NULL)) 192 goto out; 193 sock_hold(sk); 194 lock_sock(sk); 195 llc = llc_sk(sk); 196 dprintk("%s: closing local(%02X) remote(%02X)\n", __func__, 197 llc->laddr.lsap, llc->daddr.lsap); 198 if (!llc_send_disc(sk)) 199 llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo); 200 if (!sock_flag(sk, SOCK_ZAPPED)) { 201 llc_sap_put(llc->sap); 202 llc_sap_remove_socket(llc->sap, sk); 203 } 204 release_sock(sk); 205 if (llc->dev) 206 dev_put(llc->dev); 207 sock_put(sk); 208 llc_sk_free(sk); 209out: 210 return 0; 211} 212 213/** 214 * llc_ui_autoport - provide dynamically allocate SAP number 215 * 216 * Provide the caller with a dynamically allocated SAP number according 217 * to the rules that are set in this function. Returns: 0, upon failure, 218 * SAP number otherwise. 219 */ 220static int llc_ui_autoport(void) 221{ 222 struct llc_sap *sap; 223 int i, tries = 0; 224 225 while (tries < LLC_SAP_DYN_TRIES) { 226 for (i = llc_ui_sap_last_autoport; 227 i < LLC_SAP_DYN_STOP; i += 2) { 228 sap = llc_sap_find(i); 229 if (!sap) { 230 llc_ui_sap_last_autoport = i + 2; 231 goto out; 232 } 233 llc_sap_put(sap); 234 } 235 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 236 tries++; 237 } 238 i = 0; 239out: 240 return i; 241} 242 243/** 244 * llc_ui_autobind - automatically bind a socket to a sap 245 * @sock: socket to bind 246 * @addr: address to connect to 247 * 248 * Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't 249 * specifically used llc_ui_bind to bind to an specific address/sap 250 * 251 * Returns: 0 upon success, negative otherwise. 252 */ 253static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr) 254{ 255 struct sock *sk = sock->sk; 256 struct llc_sock *llc = llc_sk(sk); 257 struct llc_sap *sap; 258 int rc = -EINVAL; 259 260 if (!sock_flag(sk, SOCK_ZAPPED)) 261 goto out; 262 rc = -ENODEV; 263 if (sk->sk_bound_dev_if) { 264 llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if); 265 if (llc->dev && addr->sllc_arphrd != llc->dev->type) { 266 dev_put(llc->dev); 267 llc->dev = NULL; 268 } 269 } else 270 llc->dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd); 271 if (!llc->dev) 272 goto out; 273 rc = -EUSERS; 274 llc->laddr.lsap = llc_ui_autoport(); 275 if (!llc->laddr.lsap) 276 goto out; 277 rc = -EBUSY; /* some other network layer is using the sap */ 278 sap = llc_sap_open(llc->laddr.lsap, NULL); 279 if (!sap) 280 goto out; 281 memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN); 282 memcpy(&llc->addr, addr, sizeof(llc->addr)); 283 /* assign new connection to its SAP */ 284 llc_sap_add_socket(sap, sk); 285 sock_reset_flag(sk, SOCK_ZAPPED); 286 rc = 0; 287out: 288 return rc; 289} 290 291/** 292 * llc_ui_bind - bind a socket to a specific address. 293 * @sock: Socket to bind an address to. 294 * @uaddr: Address the user wants the socket bound to. 295 * @addrlen: Length of the uaddr structure. 296 * 297 * Bind a socket to a specific address. For llc a user is able to bind to 298 * a specific sap only or mac + sap. 299 * If the user desires to bind to a specific mac + sap, it is possible to 300 * have multiple sap connections via multiple macs. 301 * Bind and autobind for that matter must enforce the correct sap usage 302 * otherwise all hell will break loose. 303 * Returns: 0 upon success, negative otherwise. 304 */ 305static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen) 306{ 307 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr; 308 struct sock *sk = sock->sk; 309 struct llc_sock *llc = llc_sk(sk); 310 struct llc_sap *sap; 311 int rc = -EINVAL; 312 313 dprintk("%s: binding %02X\n", __func__, addr->sllc_sap); 314 if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr))) 315 goto out; 316 rc = -EAFNOSUPPORT; 317 if (unlikely(addr->sllc_family != AF_LLC)) 318 goto out; 319 rc = -ENODEV; 320 rtnl_lock(); 321 if (sk->sk_bound_dev_if) { 322 llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if); 323 if (llc->dev) { 324 if (!addr->sllc_arphrd) 325 addr->sllc_arphrd = llc->dev->type; 326 if (llc_mac_null(addr->sllc_mac)) 327 memcpy(addr->sllc_mac, llc->dev->dev_addr, 328 IFHWADDRLEN); 329 if (addr->sllc_arphrd != llc->dev->type || 330 !llc_mac_match(addr->sllc_mac, 331 llc->dev->dev_addr)) { 332 rc = -EINVAL; 333 dev_put(llc->dev); 334 llc->dev = NULL; 335 } 336 } 337 } else 338 llc->dev = dev_getbyhwaddr(&init_net, addr->sllc_arphrd, 339 addr->sllc_mac); 340 rtnl_unlock(); 341 if (!llc->dev) 342 goto out; 343 if (!addr->sllc_sap) { 344 rc = -EUSERS; 345 addr->sllc_sap = llc_ui_autoport(); 346 if (!addr->sllc_sap) 347 goto out; 348 } 349 sap = llc_sap_find(addr->sllc_sap); 350 if (!sap) { 351 sap = llc_sap_open(addr->sllc_sap, NULL); 352 rc = -EBUSY; /* some other network layer is using the sap */ 353 if (!sap) 354 goto out; 355 llc_sap_hold(sap); 356 } else { 357 struct llc_addr laddr, daddr; 358 struct sock *ask; 359 360 memset(&laddr, 0, sizeof(laddr)); 361 memset(&daddr, 0, sizeof(daddr)); 362 /* 363 * FIXME: check if the address is multicast, 364 * only SOCK_DGRAM can do this. 365 */ 366 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN); 367 laddr.lsap = addr->sllc_sap; 368 rc = -EADDRINUSE; /* mac + sap clash. */ 369 ask = llc_lookup_established(sap, &daddr, &laddr); 370 if (ask) { 371 sock_put(ask); 372 goto out_put; 373 } 374 } 375 llc->laddr.lsap = addr->sllc_sap; 376 memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN); 377 memcpy(&llc->addr, addr, sizeof(llc->addr)); 378 /* assign new connection to its SAP */ 379 llc_sap_add_socket(sap, sk); 380 sock_reset_flag(sk, SOCK_ZAPPED); 381 rc = 0; 382out_put: 383 llc_sap_put(sap); 384out: 385 return rc; 386} 387 388/** 389 * llc_ui_shutdown - shutdown a connect llc2 socket. 390 * @sock: Socket to shutdown. 391 * @how: What part of the socket to shutdown. 392 * 393 * Shutdown a connected llc2 socket. Currently this function only supports 394 * shutting down both sends and receives (2), we could probably make this 395 * function such that a user can shutdown only half the connection but not 396 * right now. 397 * Returns: 0 upon success, negative otherwise. 398 */ 399static int llc_ui_shutdown(struct socket *sock, int how) 400{ 401 struct sock *sk = sock->sk; 402 int rc = -ENOTCONN; 403 404 lock_sock(sk); 405 if (unlikely(sk->sk_state != TCP_ESTABLISHED)) 406 goto out; 407 rc = -EINVAL; 408 if (how != 2) 409 goto out; 410 rc = llc_send_disc(sk); 411 if (!rc) 412 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo); 413 /* Wake up anyone sleeping in poll */ 414 sk->sk_state_change(sk); 415out: 416 release_sock(sk); 417 return rc; 418} 419 420/** 421 * llc_ui_connect - Connect to a remote llc2 mac + sap. 422 * @sock: Socket which will be connected to the remote destination. 423 * @uaddr: Remote and possibly the local address of the new connection. 424 * @addrlen: Size of uaddr structure. 425 * @flags: Operational flags specified by the user. 426 * 427 * Connect to a remote llc2 mac + sap. The caller must specify the 428 * destination mac and address to connect to. If the user hasn't previously 429 * called bind(2) with a smac the address of the first interface of the 430 * specified arp type will be used. 431 * This function will autobind if user did not previously call bind. 432 * Returns: 0 upon success, negative otherwise. 433 */ 434static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr, 435 int addrlen, int flags) 436{ 437 struct sock *sk = sock->sk; 438 struct llc_sock *llc = llc_sk(sk); 439 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr; 440 int rc = -EINVAL; 441 442 lock_sock(sk); 443 if (unlikely(addrlen != sizeof(*addr))) 444 goto out; 445 rc = -EAFNOSUPPORT; 446 if (unlikely(addr->sllc_family != AF_LLC)) 447 goto out; 448 if (unlikely(sk->sk_type != SOCK_STREAM)) 449 goto out; 450 rc = -EALREADY; 451 if (unlikely(sock->state == SS_CONNECTING)) 452 goto out; 453 /* bind connection to sap if user hasn't done it. */ 454 if (sock_flag(sk, SOCK_ZAPPED)) { 455 /* bind to sap with null dev, exclusive */ 456 rc = llc_ui_autobind(sock, addr); 457 if (rc) 458 goto out; 459 } 460 llc->daddr.lsap = addr->sllc_sap; 461 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN); 462 sock->state = SS_CONNECTING; 463 sk->sk_state = TCP_SYN_SENT; 464 llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap); 465 rc = llc_establish_connection(sk, llc->dev->dev_addr, 466 addr->sllc_mac, addr->sllc_sap); 467 if (rc) { 468 dprintk("%s: llc_ui_send_conn failed :-(\n", __func__); 469 sock->state = SS_UNCONNECTED; 470 sk->sk_state = TCP_CLOSE; 471 goto out; 472 } 473 474 if (sk->sk_state == TCP_SYN_SENT) { 475 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); 476 477 if (!timeo || !llc_ui_wait_for_conn(sk, timeo)) 478 goto out; 479 480 rc = sock_intr_errno(timeo); 481 if (signal_pending(current)) 482 goto out; 483 } 484 485 if (sk->sk_state == TCP_CLOSE) 486 goto sock_error; 487 488 sock->state = SS_CONNECTED; 489 rc = 0; 490out: 491 release_sock(sk); 492 return rc; 493sock_error: 494 rc = sock_error(sk) ? : -ECONNABORTED; 495 sock->state = SS_UNCONNECTED; 496 goto out; 497} 498 499/** 500 * llc_ui_listen - allow a normal socket to accept incoming connections 501 * @sock: Socket to allow incoming connections on. 502 * @backlog: Number of connections to queue. 503 * 504 * Allow a normal socket to accept incoming connections. 505 * Returns 0 upon success, negative otherwise. 506 */ 507static int llc_ui_listen(struct socket *sock, int backlog) 508{ 509 struct sock *sk = sock->sk; 510 int rc = -EINVAL; 511 512 lock_sock(sk); 513 if (unlikely(sock->state != SS_UNCONNECTED)) 514 goto out; 515 rc = -EOPNOTSUPP; 516 if (unlikely(sk->sk_type != SOCK_STREAM)) 517 goto out; 518 rc = -EAGAIN; 519 if (sock_flag(sk, SOCK_ZAPPED)) 520 goto out; 521 rc = 0; 522 if (!(unsigned)backlog) /* BSDism */ 523 backlog = 1; 524 sk->sk_max_ack_backlog = backlog; 525 if (sk->sk_state != TCP_LISTEN) { 526 sk->sk_ack_backlog = 0; 527 sk->sk_state = TCP_LISTEN; 528 } 529 sk->sk_socket->flags |= __SO_ACCEPTCON; 530out: 531 release_sock(sk); 532 return rc; 533} 534 535static int llc_ui_wait_for_disc(struct sock *sk, long timeout) 536{ 537 DEFINE_WAIT(wait); 538 int rc = 0; 539 540 while (1) { 541 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); 542 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE)) 543 break; 544 rc = -ERESTARTSYS; 545 if (signal_pending(current)) 546 break; 547 rc = -EAGAIN; 548 if (!timeout) 549 break; 550 rc = 0; 551 } 552 finish_wait(sk->sk_sleep, &wait); 553 return rc; 554} 555 556static int llc_ui_wait_for_conn(struct sock *sk, long timeout) 557{ 558 DEFINE_WAIT(wait); 559 560 while (1) { 561 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); 562 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT)) 563 break; 564 if (signal_pending(current) || !timeout) 565 break; 566 } 567 finish_wait(sk->sk_sleep, &wait); 568 return timeout; 569} 570 571static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout) 572{ 573 DEFINE_WAIT(wait); 574 struct llc_sock *llc = llc_sk(sk); 575 int rc; 576 577 while (1) { 578 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); 579 rc = 0; 580 if (sk_wait_event(sk, &timeout, 581 (sk->sk_shutdown & RCV_SHUTDOWN) || 582 (!llc_data_accept_state(llc->state) && 583 !llc->remote_busy_flag && 584 !llc->p_flag))) 585 break; 586 rc = -ERESTARTSYS; 587 if (signal_pending(current)) 588 break; 589 rc = -EAGAIN; 590 if (!timeout) 591 break; 592 } 593 finish_wait(sk->sk_sleep, &wait); 594 return rc; 595} 596 597static int llc_wait_data(struct sock *sk, long timeo) 598{ 599 int rc; 600 601 while (1) { 602 /* 603 * POSIX 1003.1g mandates this order. 604 */ 605 rc = sock_error(sk); 606 if (rc) 607 break; 608 rc = 0; 609 if (sk->sk_shutdown & RCV_SHUTDOWN) 610 break; 611 rc = -EAGAIN; 612 if (!timeo) 613 break; 614 rc = sock_intr_errno(timeo); 615 if (signal_pending(current)) 616 break; 617 rc = 0; 618 if (sk_wait_data(sk, &timeo)) 619 break; 620 } 621 return rc; 622} 623 624static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb) 625{ 626 struct llc_sock *llc = llc_sk(skb->sk); 627 628 if (llc->cmsg_flags & LLC_CMSG_PKTINFO) { 629 struct llc_pktinfo info; 630 631 info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex; 632 llc_pdu_decode_dsap(skb, &info.lpi_sap); 633 llc_pdu_decode_da(skb, info.lpi_mac); 634 put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info); 635 } 636} 637 638/** 639 * llc_ui_accept - accept a new incoming connection. 640 * @sock: Socket which connections arrive on. 641 * @newsock: Socket to move incoming connection to. 642 * @flags: User specified operational flags. 643 * 644 * Accept a new incoming connection. 645 * Returns 0 upon success, negative otherwise. 646 */ 647static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags) 648{ 649 struct sock *sk = sock->sk, *newsk; 650 struct llc_sock *llc, *newllc; 651 struct sk_buff *skb; 652 int rc = -EOPNOTSUPP; 653 654 dprintk("%s: accepting on %02X\n", __func__, 655 llc_sk(sk)->laddr.lsap); 656 lock_sock(sk); 657 if (unlikely(sk->sk_type != SOCK_STREAM)) 658 goto out; 659 rc = -EINVAL; 660 if (unlikely(sock->state != SS_UNCONNECTED || 661 sk->sk_state != TCP_LISTEN)) 662 goto out; 663 /* wait for a connection to arrive. */ 664 if (skb_queue_empty(&sk->sk_receive_queue)) { 665 rc = llc_wait_data(sk, sk->sk_rcvtimeo); 666 if (rc) 667 goto out; 668 } 669 dprintk("%s: got a new connection on %02X\n", __func__, 670 llc_sk(sk)->laddr.lsap); 671 skb = skb_dequeue(&sk->sk_receive_queue); 672 rc = -EINVAL; 673 if (!skb->sk) 674 goto frees; 675 rc = 0; 676 newsk = skb->sk; 677 /* attach connection to a new socket. */ 678 llc_ui_sk_init(newsock, newsk); 679 sock_reset_flag(newsk, SOCK_ZAPPED); 680 newsk->sk_state = TCP_ESTABLISHED; 681 newsock->state = SS_CONNECTED; 682 llc = llc_sk(sk); 683 newllc = llc_sk(newsk); 684 memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr)); 685 newllc->link = llc_ui_next_link_no(newllc->laddr.lsap); 686 687 /* put original socket back into a clean listen state. */ 688 sk->sk_state = TCP_LISTEN; 689 sk->sk_ack_backlog--; 690 dprintk("%s: ok success on %02X, client on %02X\n", __func__, 691 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap); 692frees: 693 kfree_skb(skb); 694out: 695 release_sock(sk); 696 return rc; 697} 698 699/** 700 * llc_ui_recvmsg - copy received data to the socket user. 701 * @sock: Socket to copy data from. 702 * @msg: Various user space related information. 703 * @len: Size of user buffer. 704 * @flags: User specified flags. 705 * 706 * Copy received data to the socket user. 707 * Returns non-negative upon success, negative otherwise. 708 */ 709static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock, 710 struct msghdr *msg, size_t len, int flags) 711{ 712 struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name; 713 const int nonblock = flags & MSG_DONTWAIT; 714 struct sk_buff *skb = NULL; 715 struct sock *sk = sock->sk; 716 struct llc_sock *llc = llc_sk(sk); 717 size_t copied = 0; 718 u32 peek_seq = 0; 719 u32 *seq; 720 unsigned long used; 721 int target; /* Read at least this many bytes */ 722 long timeo; 723 724 lock_sock(sk); 725 copied = -ENOTCONN; 726 if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN)) 727 goto out; 728 729 timeo = sock_rcvtimeo(sk, nonblock); 730 731 seq = &llc->copied_seq; 732 if (flags & MSG_PEEK) { 733 peek_seq = llc->copied_seq; 734 seq = &peek_seq; 735 } 736 737 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 738 copied = 0; 739 740 do { 741 u32 offset; 742 743 /* 744 * We need to check signals first, to get correct SIGURG 745 * handling. FIXME: Need to check this doesn't impact 1003.1g 746 * and move it down to the bottom of the loop 747 */ 748 if (signal_pending(current)) { 749 if (copied) 750 break; 751 copied = timeo ? sock_intr_errno(timeo) : -EAGAIN; 752 break; 753 } 754 755 /* Next get a buffer. */ 756 757 skb = skb_peek(&sk->sk_receive_queue); 758 if (skb) { 759 offset = *seq; 760 goto found_ok_skb; 761 } 762 /* Well, if we have backlog, try to process it now yet. */ 763 764 if (copied >= target && !sk->sk_backlog.tail) 765 break; 766 767 if (copied) { 768 if (sk->sk_err || 769 sk->sk_state == TCP_CLOSE || 770 (sk->sk_shutdown & RCV_SHUTDOWN) || 771 !timeo || 772 (flags & MSG_PEEK)) 773 break; 774 } else { 775 if (sock_flag(sk, SOCK_DONE)) 776 break; 777 778 if (sk->sk_err) { 779 copied = sock_error(sk); 780 break; 781 } 782 if (sk->sk_shutdown & RCV_SHUTDOWN) 783 break; 784 785 if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) { 786 if (!sock_flag(sk, SOCK_DONE)) { 787 /* 788 * This occurs when user tries to read 789 * from never connected socket. 790 */ 791 copied = -ENOTCONN; 792 break; 793 } 794 break; 795 } 796 if (!timeo) { 797 copied = -EAGAIN; 798 break; 799 } 800 } 801 802 if (copied >= target) { /* Do not sleep, just process backlog. */ 803 release_sock(sk); 804 lock_sock(sk); 805 } else 806 sk_wait_data(sk, &timeo); 807 808 if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) { 809 if (net_ratelimit()) 810 printk(KERN_DEBUG "LLC(%s:%d): Application " 811 "bug, race in MSG_PEEK.\n", 812 current->comm, task_pid_nr(current)); 813 peek_seq = llc->copied_seq; 814 } 815 continue; 816 found_ok_skb: 817 /* Ok so how much can we use? */ 818 used = skb->len - offset; 819 if (len < used) 820 used = len; 821 822 if (!(flags & MSG_TRUNC)) { 823 int rc = skb_copy_datagram_iovec(skb, offset, 824 msg->msg_iov, used); 825 if (rc) { 826 /* Exception. Bailout! */ 827 if (!copied) 828 copied = -EFAULT; 829 break; 830 } 831 } 832 833 *seq += used; 834 copied += used; 835 len -= used; 836 837 if (!(flags & MSG_PEEK)) { 838 sk_eat_skb(sk, skb, 0); 839 *seq = 0; 840 } 841 842 /* For non stream protcols we get one packet per recvmsg call */ 843 if (sk->sk_type != SOCK_STREAM) 844 goto copy_uaddr; 845 846 /* Partial read */ 847 if (used + offset < skb->len) 848 continue; 849 } while (len > 0); 850 851out: 852 release_sock(sk); 853 return copied; 854copy_uaddr: 855 if (uaddr != NULL && skb != NULL) { 856 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr)); 857 msg->msg_namelen = sizeof(*uaddr); 858 } 859 if (llc_sk(sk)->cmsg_flags) 860 llc_cmsg_rcv(msg, skb); 861 goto out; 862} 863 864/** 865 * llc_ui_sendmsg - Transmit data provided by the socket user. 866 * @sock: Socket to transmit data from. 867 * @msg: Various user related information. 868 * @len: Length of data to transmit. 869 * 870 * Transmit data provided by the socket user. 871 * Returns non-negative upon success, negative otherwise. 872 */ 873static int llc_ui_sendmsg(struct kiocb *iocb, struct socket *sock, 874 struct msghdr *msg, size_t len) 875{ 876 struct sock *sk = sock->sk; 877 struct llc_sock *llc = llc_sk(sk); 878 struct sockaddr_llc *addr = (struct sockaddr_llc *)msg->msg_name; 879 int flags = msg->msg_flags; 880 int noblock = flags & MSG_DONTWAIT; 881 struct sk_buff *skb; 882 size_t size = 0; 883 int rc = -EINVAL, copied = 0, hdrlen; 884 885 dprintk("%s: sending from %02X to %02X\n", __func__, 886 llc->laddr.lsap, llc->daddr.lsap); 887 lock_sock(sk); 888 if (addr) { 889 if (msg->msg_namelen < sizeof(*addr)) 890 goto release; 891 } else { 892 if (llc_ui_addr_null(&llc->addr)) 893 goto release; 894 addr = &llc->addr; 895 } 896 /* must bind connection to sap if user hasn't done it. */ 897 if (sock_flag(sk, SOCK_ZAPPED)) { 898 /* bind to sap with null dev, exclusive. */ 899 rc = llc_ui_autobind(sock, addr); 900 if (rc) 901 goto release; 902 } 903 hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr); 904 size = hdrlen + len; 905 if (size > llc->dev->mtu) 906 size = llc->dev->mtu; 907 copied = size - hdrlen; 908 release_sock(sk); 909 skb = sock_alloc_send_skb(sk, size, noblock, &rc); 910 lock_sock(sk); 911 if (!skb) 912 goto release; 913 skb->dev = llc->dev; 914 skb->protocol = llc_proto_type(addr->sllc_arphrd); 915 skb_reserve(skb, hdrlen); 916 rc = memcpy_fromiovec(skb_put(skb, copied), msg->msg_iov, copied); 917 if (rc) 918 goto out; 919 if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) { 920 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac, 921 addr->sllc_sap); 922 goto out; 923 } 924 if (addr->sllc_test) { 925 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac, 926 addr->sllc_sap); 927 goto out; 928 } 929 if (addr->sllc_xid) { 930 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac, 931 addr->sllc_sap); 932 goto out; 933 } 934 rc = -ENOPROTOOPT; 935 if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua)) 936 goto out; 937 rc = llc_ui_send_data(sk, skb, noblock); 938out: 939 if (rc) { 940 kfree_skb(skb); 941release: 942 dprintk("%s: failed sending from %02X to %02X: %d\n", 943 __func__, llc->laddr.lsap, llc->daddr.lsap, rc); 944 } 945 release_sock(sk); 946 return rc ? : copied; 947} 948 949/** 950 * llc_ui_getname - return the address info of a socket 951 * @sock: Socket to get address of. 952 * @uaddr: Address structure to return information. 953 * @uaddrlen: Length of address structure. 954 * @peer: Does user want local or remote address information. 955 * 956 * Return the address information of a socket. 957 */ 958static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr, 959 int *uaddrlen, int peer) 960{ 961 struct sockaddr_llc sllc; 962 struct sock *sk = sock->sk; 963 struct llc_sock *llc = llc_sk(sk); 964 int rc = 0; 965 966 memset(&sllc, 0, sizeof(sllc)); 967 lock_sock(sk); 968 if (sock_flag(sk, SOCK_ZAPPED)) 969 goto out; 970 *uaddrlen = sizeof(sllc); 971 memset(uaddr, 0, *uaddrlen); 972 if (peer) { 973 rc = -ENOTCONN; 974 if (sk->sk_state != TCP_ESTABLISHED) 975 goto out; 976 if(llc->dev) 977 sllc.sllc_arphrd = llc->dev->type; 978 sllc.sllc_sap = llc->daddr.lsap; 979 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN); 980 } else { 981 rc = -EINVAL; 982 if (!llc->sap) 983 goto out; 984 sllc.sllc_sap = llc->sap->laddr.lsap; 985 986 if (llc->dev) { 987 sllc.sllc_arphrd = llc->dev->type; 988 memcpy(&sllc.sllc_mac, llc->dev->dev_addr, 989 IFHWADDRLEN); 990 } 991 } 992 rc = 0; 993 sllc.sllc_family = AF_LLC; 994 memcpy(uaddr, &sllc, sizeof(sllc)); 995out: 996 release_sock(sk); 997 return rc; 998} 999 1000/** 1001 * llc_ui_ioctl - io controls for PF_LLC 1002 * @sock: Socket to get/set info 1003 * @cmd: command 1004 * @arg: optional argument for cmd 1005 * 1006 * get/set info on llc sockets 1007 */ 1008static int llc_ui_ioctl(struct socket *sock, unsigned int cmd, 1009 unsigned long arg) 1010{ 1011 return -ENOIOCTLCMD; 1012} 1013 1014/** 1015 * llc_ui_setsockopt - set various connection specific parameters. 1016 * @sock: Socket to set options on. 1017 * @level: Socket level user is requesting operations on. 1018 * @optname: Operation name. 1019 * @optval User provided operation data. 1020 * @optlen: Length of optval. 1021 * 1022 * Set various connection specific parameters. 1023 */ 1024static int llc_ui_setsockopt(struct socket *sock, int level, int optname, 1025 char __user *optval, unsigned int optlen) 1026{ 1027 struct sock *sk = sock->sk; 1028 struct llc_sock *llc = llc_sk(sk); 1029 int rc = -EINVAL, opt; 1030 1031 lock_sock(sk); 1032 if (unlikely(level != SOL_LLC || optlen != sizeof(int))) 1033 goto out; 1034 rc = get_user(opt, (int __user *)optval); 1035 if (rc) 1036 goto out; 1037 rc = -EINVAL; 1038 switch (optname) { 1039 case LLC_OPT_RETRY: 1040 if (opt > LLC_OPT_MAX_RETRY) 1041 goto out; 1042 llc->n2 = opt; 1043 break; 1044 case LLC_OPT_SIZE: 1045 if (opt > LLC_OPT_MAX_SIZE) 1046 goto out; 1047 llc->n1 = opt; 1048 break; 1049 case LLC_OPT_ACK_TMR_EXP: 1050 if (opt > LLC_OPT_MAX_ACK_TMR_EXP) 1051 goto out; 1052 llc->ack_timer.expire = opt * HZ; 1053 break; 1054 case LLC_OPT_P_TMR_EXP: 1055 if (opt > LLC_OPT_MAX_P_TMR_EXP) 1056 goto out; 1057 llc->pf_cycle_timer.expire = opt * HZ; 1058 break; 1059 case LLC_OPT_REJ_TMR_EXP: 1060 if (opt > LLC_OPT_MAX_REJ_TMR_EXP) 1061 goto out; 1062 llc->rej_sent_timer.expire = opt * HZ; 1063 break; 1064 case LLC_OPT_BUSY_TMR_EXP: 1065 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP) 1066 goto out; 1067 llc->busy_state_timer.expire = opt * HZ; 1068 break; 1069 case LLC_OPT_TX_WIN: 1070 if (opt > LLC_OPT_MAX_WIN) 1071 goto out; 1072 llc->k = opt; 1073 break; 1074 case LLC_OPT_RX_WIN: 1075 if (opt > LLC_OPT_MAX_WIN) 1076 goto out; 1077 llc->rw = opt; 1078 break; 1079 case LLC_OPT_PKTINFO: 1080 if (opt) 1081 llc->cmsg_flags |= LLC_CMSG_PKTINFO; 1082 else 1083 llc->cmsg_flags &= ~LLC_CMSG_PKTINFO; 1084 break; 1085 default: 1086 rc = -ENOPROTOOPT; 1087 goto out; 1088 } 1089 rc = 0; 1090out: 1091 release_sock(sk); 1092 return rc; 1093} 1094 1095/** 1096 * llc_ui_getsockopt - get connection specific socket info 1097 * @sock: Socket to get information from. 1098 * @level: Socket level user is requesting operations on. 1099 * @optname: Operation name. 1100 * @optval: Variable to return operation data in. 1101 * @optlen: Length of optval. 1102 * 1103 * Get connection specific socket information. 1104 */ 1105static int llc_ui_getsockopt(struct socket *sock, int level, int optname, 1106 char __user *optval, int __user *optlen) 1107{ 1108 struct sock *sk = sock->sk; 1109 struct llc_sock *llc = llc_sk(sk); 1110 int val = 0, len = 0, rc = -EINVAL; 1111 1112 lock_sock(sk); 1113 if (unlikely(level != SOL_LLC)) 1114 goto out; 1115 rc = get_user(len, optlen); 1116 if (rc) 1117 goto out; 1118 rc = -EINVAL; 1119 if (len != sizeof(int)) 1120 goto out; 1121 switch (optname) { 1122 case LLC_OPT_RETRY: 1123 val = llc->n2; break; 1124 case LLC_OPT_SIZE: 1125 val = llc->n1; break; 1126 case LLC_OPT_ACK_TMR_EXP: 1127 val = llc->ack_timer.expire / HZ; break; 1128 case LLC_OPT_P_TMR_EXP: 1129 val = llc->pf_cycle_timer.expire / HZ; break; 1130 case LLC_OPT_REJ_TMR_EXP: 1131 val = llc->rej_sent_timer.expire / HZ; break; 1132 case LLC_OPT_BUSY_TMR_EXP: 1133 val = llc->busy_state_timer.expire / HZ; break; 1134 case LLC_OPT_TX_WIN: 1135 val = llc->k; break; 1136 case LLC_OPT_RX_WIN: 1137 val = llc->rw; break; 1138 case LLC_OPT_PKTINFO: 1139 val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0; 1140 break; 1141 default: 1142 rc = -ENOPROTOOPT; 1143 goto out; 1144 } 1145 rc = 0; 1146 if (put_user(len, optlen) || copy_to_user(optval, &val, len)) 1147 rc = -EFAULT; 1148out: 1149 release_sock(sk); 1150 return rc; 1151} 1152 1153static const struct net_proto_family llc_ui_family_ops = { 1154 .family = PF_LLC, 1155 .create = llc_ui_create, 1156 .owner = THIS_MODULE, 1157}; 1158 1159static const struct proto_ops llc_ui_ops = { 1160 .family = PF_LLC, 1161 .owner = THIS_MODULE, 1162 .release = llc_ui_release, 1163 .bind = llc_ui_bind, 1164 .connect = llc_ui_connect, 1165 .socketpair = sock_no_socketpair, 1166 .accept = llc_ui_accept, 1167 .getname = llc_ui_getname, 1168 .poll = datagram_poll, 1169 .ioctl = llc_ui_ioctl, 1170 .listen = llc_ui_listen, 1171 .shutdown = llc_ui_shutdown, 1172 .setsockopt = llc_ui_setsockopt, 1173 .getsockopt = llc_ui_getsockopt, 1174 .sendmsg = llc_ui_sendmsg, 1175 .recvmsg = llc_ui_recvmsg, 1176 .mmap = sock_no_mmap, 1177 .sendpage = sock_no_sendpage, 1178}; 1179 1180static const char llc_proc_err_msg[] __initconst = 1181 KERN_CRIT "LLC: Unable to register the proc_fs entries\n"; 1182static const char llc_sysctl_err_msg[] __initconst = 1183 KERN_CRIT "LLC: Unable to register the sysctl entries\n"; 1184static const char llc_sock_err_msg[] __initconst = 1185 KERN_CRIT "LLC: Unable to register the network family\n"; 1186 1187static int __init llc2_init(void) 1188{ 1189 int rc = proto_register(&llc_proto, 0); 1190 1191 if (rc != 0) 1192 goto out; 1193 1194 llc_build_offset_table(); 1195 llc_station_init(); 1196 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 1197 rc = llc_proc_init(); 1198 if (rc != 0) { 1199 printk(llc_proc_err_msg); 1200 goto out_unregister_llc_proto; 1201 } 1202 rc = llc_sysctl_init(); 1203 if (rc) { 1204 printk(llc_sysctl_err_msg); 1205 goto out_proc; 1206 } 1207 rc = sock_register(&llc_ui_family_ops); 1208 if (rc) { 1209 printk(llc_sock_err_msg); 1210 goto out_sysctl; 1211 } 1212 llc_add_pack(LLC_DEST_SAP, llc_sap_handler); 1213 llc_add_pack(LLC_DEST_CONN, llc_conn_handler); 1214out: 1215 return rc; 1216out_sysctl: 1217 llc_sysctl_exit(); 1218out_proc: 1219 llc_proc_exit(); 1220out_unregister_llc_proto: 1221 proto_unregister(&llc_proto); 1222 goto out; 1223} 1224 1225static void __exit llc2_exit(void) 1226{ 1227 llc_station_exit(); 1228 llc_remove_pack(LLC_DEST_SAP); 1229 llc_remove_pack(LLC_DEST_CONN); 1230 sock_unregister(PF_LLC); 1231 llc_proc_exit(); 1232 llc_sysctl_exit(); 1233 proto_unregister(&llc_proto); 1234} 1235 1236module_init(llc2_init); 1237module_exit(llc2_exit); 1238 1239MODULE_LICENSE("GPL"); 1240MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003"); 1241MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support"); 1242MODULE_ALIAS_NETPROTO(PF_LLC); 1243