af_llc.c revision e87cc4728f0e2fb663e592a1141742b1d6c63256
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#if 0 46#define dprintk(args...) printk(KERN_DEBUG args) 47#else 48#define dprintk(args...) 49#endif 50 51/* Maybe we'll add some more in the future. */ 52#define LLC_CMSG_PKTINFO 1 53 54 55/** 56 * llc_ui_next_link_no - return the next unused link number for a sap 57 * @sap: Address of sap to get link number from. 58 * 59 * Return the next unused link number for a given sap. 60 */ 61static inline u16 llc_ui_next_link_no(int sap) 62{ 63 return llc_ui_sap_link_no_max[sap]++; 64} 65 66/** 67 * llc_proto_type - return eth protocol for ARP header type 68 * @arphrd: ARP header type. 69 * 70 * Given an ARP header type return the corresponding ethernet protocol. 71 */ 72static inline __be16 llc_proto_type(u16 arphrd) 73{ 74 return arphrd == ARPHRD_IEEE802_TR ? 75 htons(ETH_P_TR_802_2) : htons(ETH_P_802_2); 76} 77 78/** 79 * llc_ui_addr_null - determines if a address structure is null 80 * @addr: Address to test if null. 81 */ 82static inline u8 llc_ui_addr_null(struct sockaddr_llc *addr) 83{ 84 return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr)); 85} 86 87/** 88 * llc_ui_header_len - return length of llc header based on operation 89 * @sk: Socket which contains a valid llc socket type. 90 * @addr: Complete sockaddr_llc structure received from the user. 91 * 92 * Provide the length of the llc header depending on what kind of 93 * operation the user would like to perform and the type of socket. 94 * Returns the correct llc header length. 95 */ 96static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr) 97{ 98 u8 rc = LLC_PDU_LEN_U; 99 100 if (addr->sllc_test || addr->sllc_xid) 101 rc = LLC_PDU_LEN_U; 102 else if (sk->sk_type == SOCK_STREAM) 103 rc = LLC_PDU_LEN_I; 104 return rc; 105} 106 107/** 108 * llc_ui_send_data - send data via reliable llc2 connection 109 * @sk: Connection the socket is using. 110 * @skb: Data the user wishes to send. 111 * @noblock: can we block waiting for data? 112 * 113 * Send data via reliable llc2 connection. 114 * Returns 0 upon success, non-zero if action did not succeed. 115 */ 116static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock) 117{ 118 struct llc_sock* llc = llc_sk(sk); 119 int rc = 0; 120 121 if (unlikely(llc_data_accept_state(llc->state) || 122 llc->remote_busy_flag || 123 llc->p_flag)) { 124 long timeout = sock_sndtimeo(sk, noblock); 125 126 rc = llc_ui_wait_for_busy_core(sk, timeout); 127 } 128 if (unlikely(!rc)) 129 rc = llc_build_and_send_pkt(sk, skb); 130 return rc; 131} 132 133static void llc_ui_sk_init(struct socket *sock, struct sock *sk) 134{ 135 sock_graft(sk, sock); 136 sk->sk_type = sock->type; 137 sock->ops = &llc_ui_ops; 138} 139 140static struct proto llc_proto = { 141 .name = "LLC", 142 .owner = THIS_MODULE, 143 .obj_size = sizeof(struct llc_sock), 144 .slab_flags = SLAB_DESTROY_BY_RCU, 145}; 146 147/** 148 * llc_ui_create - alloc and init a new llc_ui socket 149 * @net: network namespace (must be default network) 150 * @sock: Socket to initialize and attach allocated sk to. 151 * @protocol: Unused. 152 * @kern: on behalf of kernel or userspace 153 * 154 * Allocate and initialize a new llc_ui socket, validate the user wants a 155 * socket type we have available. 156 * Returns 0 upon success, negative upon failure. 157 */ 158static int llc_ui_create(struct net *net, struct socket *sock, int protocol, 159 int kern) 160{ 161 struct sock *sk; 162 int rc = -ESOCKTNOSUPPORT; 163 164 if (!capable(CAP_NET_RAW)) 165 return -EPERM; 166 167 if (!net_eq(net, &init_net)) 168 return -EAFNOSUPPORT; 169 170 if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) { 171 rc = -ENOMEM; 172 sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto); 173 if (sk) { 174 rc = 0; 175 llc_ui_sk_init(sock, sk); 176 } 177 } 178 return rc; 179} 180 181/** 182 * llc_ui_release - shutdown socket 183 * @sock: Socket to release. 184 * 185 * Shutdown and deallocate an existing socket. 186 */ 187static int llc_ui_release(struct socket *sock) 188{ 189 struct sock *sk = sock->sk; 190 struct llc_sock *llc; 191 192 if (unlikely(sk == NULL)) 193 goto out; 194 sock_hold(sk); 195 lock_sock(sk); 196 llc = llc_sk(sk); 197 dprintk("%s: closing local(%02X) remote(%02X)\n", __func__, 198 llc->laddr.lsap, llc->daddr.lsap); 199 if (!llc_send_disc(sk)) 200 llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo); 201 if (!sock_flag(sk, SOCK_ZAPPED)) 202 llc_sap_remove_socket(llc->sap, sk); 203 release_sock(sk); 204 if (llc->dev) 205 dev_put(llc->dev); 206 sock_put(sk); 207 llc_sk_free(sk); 208out: 209 return 0; 210} 211 212/** 213 * llc_ui_autoport - provide dynamically allocate SAP number 214 * 215 * Provide the caller with a dynamically allocated SAP number according 216 * to the rules that are set in this function. Returns: 0, upon failure, 217 * SAP number otherwise. 218 */ 219static int llc_ui_autoport(void) 220{ 221 struct llc_sap *sap; 222 int i, tries = 0; 223 224 while (tries < LLC_SAP_DYN_TRIES) { 225 for (i = llc_ui_sap_last_autoport; 226 i < LLC_SAP_DYN_STOP; i += 2) { 227 sap = llc_sap_find(i); 228 if (!sap) { 229 llc_ui_sap_last_autoport = i + 2; 230 goto out; 231 } 232 llc_sap_put(sap); 233 } 234 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 235 tries++; 236 } 237 i = 0; 238out: 239 return i; 240} 241 242/** 243 * llc_ui_autobind - automatically bind a socket to a sap 244 * @sock: socket to bind 245 * @addr: address to connect to 246 * 247 * Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't 248 * specifically used llc_ui_bind to bind to an specific address/sap 249 * 250 * Returns: 0 upon success, negative otherwise. 251 */ 252static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr) 253{ 254 struct sock *sk = sock->sk; 255 struct llc_sock *llc = llc_sk(sk); 256 struct llc_sap *sap; 257 int rc = -EINVAL; 258 259 if (!sock_flag(sk, SOCK_ZAPPED)) 260 goto out; 261 rc = -ENODEV; 262 if (sk->sk_bound_dev_if) { 263 llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if); 264 if (llc->dev && addr->sllc_arphrd != llc->dev->type) { 265 dev_put(llc->dev); 266 llc->dev = NULL; 267 } 268 } else 269 llc->dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd); 270 if (!llc->dev) 271 goto out; 272 rc = -EUSERS; 273 llc->laddr.lsap = llc_ui_autoport(); 274 if (!llc->laddr.lsap) 275 goto out; 276 rc = -EBUSY; /* some other network layer is using the sap */ 277 sap = llc_sap_open(llc->laddr.lsap, NULL); 278 if (!sap) 279 goto out; 280 memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN); 281 memcpy(&llc->addr, addr, sizeof(llc->addr)); 282 /* assign new connection to its SAP */ 283 llc_sap_add_socket(sap, sk); 284 sock_reset_flag(sk, SOCK_ZAPPED); 285 rc = 0; 286out: 287 return rc; 288} 289 290/** 291 * llc_ui_bind - bind a socket to a specific address. 292 * @sock: Socket to bind an address to. 293 * @uaddr: Address the user wants the socket bound to. 294 * @addrlen: Length of the uaddr structure. 295 * 296 * Bind a socket to a specific address. For llc a user is able to bind to 297 * a specific sap only or mac + sap. 298 * If the user desires to bind to a specific mac + sap, it is possible to 299 * have multiple sap connections via multiple macs. 300 * Bind and autobind for that matter must enforce the correct sap usage 301 * otherwise all hell will break loose. 302 * Returns: 0 upon success, negative otherwise. 303 */ 304static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen) 305{ 306 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr; 307 struct sock *sk = sock->sk; 308 struct llc_sock *llc = llc_sk(sk); 309 struct llc_sap *sap; 310 int rc = -EINVAL; 311 312 dprintk("%s: binding %02X\n", __func__, addr->sllc_sap); 313 if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr))) 314 goto out; 315 rc = -EAFNOSUPPORT; 316 if (unlikely(addr->sllc_family != AF_LLC)) 317 goto out; 318 rc = -ENODEV; 319 rcu_read_lock(); 320 if (sk->sk_bound_dev_if) { 321 llc->dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if); 322 if (llc->dev) { 323 if (!addr->sllc_arphrd) 324 addr->sllc_arphrd = llc->dev->type; 325 if (llc_mac_null(addr->sllc_mac)) 326 memcpy(addr->sllc_mac, llc->dev->dev_addr, 327 IFHWADDRLEN); 328 if (addr->sllc_arphrd != llc->dev->type || 329 !llc_mac_match(addr->sllc_mac, 330 llc->dev->dev_addr)) { 331 rc = -EINVAL; 332 llc->dev = NULL; 333 } 334 } 335 } else 336 llc->dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd, 337 addr->sllc_mac); 338 if (llc->dev) 339 dev_hold(llc->dev); 340 rcu_read_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 } else { 356 struct llc_addr laddr, daddr; 357 struct sock *ask; 358 359 memset(&laddr, 0, sizeof(laddr)); 360 memset(&daddr, 0, sizeof(daddr)); 361 /* 362 * FIXME: check if the address is multicast, 363 * only SOCK_DGRAM can do this. 364 */ 365 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN); 366 laddr.lsap = addr->sllc_sap; 367 rc = -EADDRINUSE; /* mac + sap clash. */ 368 ask = llc_lookup_established(sap, &daddr, &laddr); 369 if (ask) { 370 sock_put(ask); 371 goto out_put; 372 } 373 } 374 llc->laddr.lsap = addr->sllc_sap; 375 memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN); 376 memcpy(&llc->addr, addr, sizeof(llc->addr)); 377 /* assign new connection to its SAP */ 378 llc_sap_add_socket(sap, sk); 379 sock_reset_flag(sk, SOCK_ZAPPED); 380 rc = 0; 381out_put: 382 llc_sap_put(sap); 383out: 384 return rc; 385} 386 387/** 388 * llc_ui_shutdown - shutdown a connect llc2 socket. 389 * @sock: Socket to shutdown. 390 * @how: What part of the socket to shutdown. 391 * 392 * Shutdown a connected llc2 socket. Currently this function only supports 393 * shutting down both sends and receives (2), we could probably make this 394 * function such that a user can shutdown only half the connection but not 395 * right now. 396 * Returns: 0 upon success, negative otherwise. 397 */ 398static int llc_ui_shutdown(struct socket *sock, int how) 399{ 400 struct sock *sk = sock->sk; 401 int rc = -ENOTCONN; 402 403 lock_sock(sk); 404 if (unlikely(sk->sk_state != TCP_ESTABLISHED)) 405 goto out; 406 rc = -EINVAL; 407 if (how != 2) 408 goto out; 409 rc = llc_send_disc(sk); 410 if (!rc) 411 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo); 412 /* Wake up anyone sleeping in poll */ 413 sk->sk_state_change(sk); 414out: 415 release_sock(sk); 416 return rc; 417} 418 419/** 420 * llc_ui_connect - Connect to a remote llc2 mac + sap. 421 * @sock: Socket which will be connected to the remote destination. 422 * @uaddr: Remote and possibly the local address of the new connection. 423 * @addrlen: Size of uaddr structure. 424 * @flags: Operational flags specified by the user. 425 * 426 * Connect to a remote llc2 mac + sap. The caller must specify the 427 * destination mac and address to connect to. If the user hasn't previously 428 * called bind(2) with a smac the address of the first interface of the 429 * specified arp type will be used. 430 * This function will autobind if user did not previously call bind. 431 * Returns: 0 upon success, negative otherwise. 432 */ 433static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr, 434 int addrlen, int flags) 435{ 436 struct sock *sk = sock->sk; 437 struct llc_sock *llc = llc_sk(sk); 438 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr; 439 int rc = -EINVAL; 440 441 lock_sock(sk); 442 if (unlikely(addrlen != sizeof(*addr))) 443 goto out; 444 rc = -EAFNOSUPPORT; 445 if (unlikely(addr->sllc_family != AF_LLC)) 446 goto out; 447 if (unlikely(sk->sk_type != SOCK_STREAM)) 448 goto out; 449 rc = -EALREADY; 450 if (unlikely(sock->state == SS_CONNECTING)) 451 goto out; 452 /* bind connection to sap if user hasn't done it. */ 453 if (sock_flag(sk, SOCK_ZAPPED)) { 454 /* bind to sap with null dev, exclusive */ 455 rc = llc_ui_autobind(sock, addr); 456 if (rc) 457 goto out; 458 } 459 llc->daddr.lsap = addr->sllc_sap; 460 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN); 461 sock->state = SS_CONNECTING; 462 sk->sk_state = TCP_SYN_SENT; 463 llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap); 464 rc = llc_establish_connection(sk, llc->dev->dev_addr, 465 addr->sllc_mac, addr->sllc_sap); 466 if (rc) { 467 dprintk("%s: llc_ui_send_conn failed :-(\n", __func__); 468 sock->state = SS_UNCONNECTED; 469 sk->sk_state = TCP_CLOSE; 470 goto out; 471 } 472 473 if (sk->sk_state == TCP_SYN_SENT) { 474 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); 475 476 if (!timeo || !llc_ui_wait_for_conn(sk, timeo)) 477 goto out; 478 479 rc = sock_intr_errno(timeo); 480 if (signal_pending(current)) 481 goto out; 482 } 483 484 if (sk->sk_state == TCP_CLOSE) 485 goto sock_error; 486 487 sock->state = SS_CONNECTED; 488 rc = 0; 489out: 490 release_sock(sk); 491 return rc; 492sock_error: 493 rc = sock_error(sk) ? : -ECONNABORTED; 494 sock->state = SS_UNCONNECTED; 495 goto out; 496} 497 498/** 499 * llc_ui_listen - allow a normal socket to accept incoming connections 500 * @sock: Socket to allow incoming connections on. 501 * @backlog: Number of connections to queue. 502 * 503 * Allow a normal socket to accept incoming connections. 504 * Returns 0 upon success, negative otherwise. 505 */ 506static int llc_ui_listen(struct socket *sock, int backlog) 507{ 508 struct sock *sk = sock->sk; 509 int rc = -EINVAL; 510 511 lock_sock(sk); 512 if (unlikely(sock->state != SS_UNCONNECTED)) 513 goto out; 514 rc = -EOPNOTSUPP; 515 if (unlikely(sk->sk_type != SOCK_STREAM)) 516 goto out; 517 rc = -EAGAIN; 518 if (sock_flag(sk, SOCK_ZAPPED)) 519 goto out; 520 rc = 0; 521 if (!(unsigned int)backlog) /* BSDism */ 522 backlog = 1; 523 sk->sk_max_ack_backlog = backlog; 524 if (sk->sk_state != TCP_LISTEN) { 525 sk->sk_ack_backlog = 0; 526 sk->sk_state = TCP_LISTEN; 527 } 528 sk->sk_socket->flags |= __SO_ACCEPTCON; 529out: 530 release_sock(sk); 531 return rc; 532} 533 534static int llc_ui_wait_for_disc(struct sock *sk, long timeout) 535{ 536 DEFINE_WAIT(wait); 537 int rc = 0; 538 539 while (1) { 540 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 541 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE)) 542 break; 543 rc = -ERESTARTSYS; 544 if (signal_pending(current)) 545 break; 546 rc = -EAGAIN; 547 if (!timeout) 548 break; 549 rc = 0; 550 } 551 finish_wait(sk_sleep(sk), &wait); 552 return rc; 553} 554 555static int llc_ui_wait_for_conn(struct sock *sk, long timeout) 556{ 557 DEFINE_WAIT(wait); 558 559 while (1) { 560 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 561 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT)) 562 break; 563 if (signal_pending(current) || !timeout) 564 break; 565 } 566 finish_wait(sk_sleep(sk), &wait); 567 return timeout; 568} 569 570static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout) 571{ 572 DEFINE_WAIT(wait); 573 struct llc_sock *llc = llc_sk(sk); 574 int rc; 575 576 while (1) { 577 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 578 rc = 0; 579 if (sk_wait_event(sk, &timeout, 580 (sk->sk_shutdown & RCV_SHUTDOWN) || 581 (!llc_data_accept_state(llc->state) && 582 !llc->remote_busy_flag && 583 !llc->p_flag))) 584 break; 585 rc = -ERESTARTSYS; 586 if (signal_pending(current)) 587 break; 588 rc = -EAGAIN; 589 if (!timeout) 590 break; 591 } 592 finish_wait(sk_sleep(sk), &wait); 593 return rc; 594} 595 596static int llc_wait_data(struct sock *sk, long timeo) 597{ 598 int rc; 599 600 while (1) { 601 /* 602 * POSIX 1003.1g mandates this order. 603 */ 604 rc = sock_error(sk); 605 if (rc) 606 break; 607 rc = 0; 608 if (sk->sk_shutdown & RCV_SHUTDOWN) 609 break; 610 rc = -EAGAIN; 611 if (!timeo) 612 break; 613 rc = sock_intr_errno(timeo); 614 if (signal_pending(current)) 615 break; 616 rc = 0; 617 if (sk_wait_data(sk, &timeo)) 618 break; 619 } 620 return rc; 621} 622 623static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb) 624{ 625 struct llc_sock *llc = llc_sk(skb->sk); 626 627 if (llc->cmsg_flags & LLC_CMSG_PKTINFO) { 628 struct llc_pktinfo info; 629 630 info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex; 631 llc_pdu_decode_dsap(skb, &info.lpi_sap); 632 llc_pdu_decode_da(skb, info.lpi_mac); 633 put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info); 634 } 635} 636 637/** 638 * llc_ui_accept - accept a new incoming connection. 639 * @sock: Socket which connections arrive on. 640 * @newsock: Socket to move incoming connection to. 641 * @flags: User specified operational flags. 642 * 643 * Accept a new incoming connection. 644 * Returns 0 upon success, negative otherwise. 645 */ 646static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags) 647{ 648 struct sock *sk = sock->sk, *newsk; 649 struct llc_sock *llc, *newllc; 650 struct sk_buff *skb; 651 int rc = -EOPNOTSUPP; 652 653 dprintk("%s: accepting on %02X\n", __func__, 654 llc_sk(sk)->laddr.lsap); 655 lock_sock(sk); 656 if (unlikely(sk->sk_type != SOCK_STREAM)) 657 goto out; 658 rc = -EINVAL; 659 if (unlikely(sock->state != SS_UNCONNECTED || 660 sk->sk_state != TCP_LISTEN)) 661 goto out; 662 /* wait for a connection to arrive. */ 663 if (skb_queue_empty(&sk->sk_receive_queue)) { 664 rc = llc_wait_data(sk, sk->sk_rcvtimeo); 665 if (rc) 666 goto out; 667 } 668 dprintk("%s: got a new connection on %02X\n", __func__, 669 llc_sk(sk)->laddr.lsap); 670 skb = skb_dequeue(&sk->sk_receive_queue); 671 rc = -EINVAL; 672 if (!skb->sk) 673 goto frees; 674 rc = 0; 675 newsk = skb->sk; 676 /* attach connection to a new socket. */ 677 llc_ui_sk_init(newsock, newsk); 678 sock_reset_flag(newsk, SOCK_ZAPPED); 679 newsk->sk_state = TCP_ESTABLISHED; 680 newsock->state = SS_CONNECTED; 681 llc = llc_sk(sk); 682 newllc = llc_sk(newsk); 683 memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr)); 684 newllc->link = llc_ui_next_link_no(newllc->laddr.lsap); 685 686 /* put original socket back into a clean listen state. */ 687 sk->sk_state = TCP_LISTEN; 688 sk->sk_ack_backlog--; 689 dprintk("%s: ok success on %02X, client on %02X\n", __func__, 690 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap); 691frees: 692 kfree_skb(skb); 693out: 694 release_sock(sk); 695 return rc; 696} 697 698/** 699 * llc_ui_recvmsg - copy received data to the socket user. 700 * @sock: Socket to copy data from. 701 * @msg: Various user space related information. 702 * @len: Size of user buffer. 703 * @flags: User specified flags. 704 * 705 * Copy received data to the socket user. 706 * Returns non-negative upon success, negative otherwise. 707 */ 708static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock, 709 struct msghdr *msg, size_t len, int flags) 710{ 711 struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name; 712 const int nonblock = flags & MSG_DONTWAIT; 713 struct sk_buff *skb = NULL; 714 struct sock *sk = sock->sk; 715 struct llc_sock *llc = llc_sk(sk); 716 unsigned long cpu_flags; 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 net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n", 810 current->comm, 811 task_pid_nr(current)); 812 peek_seq = llc->copied_seq; 813 } 814 continue; 815 found_ok_skb: 816 /* Ok so how much can we use? */ 817 used = skb->len - offset; 818 if (len < used) 819 used = len; 820 821 if (!(flags & MSG_TRUNC)) { 822 int rc = skb_copy_datagram_iovec(skb, offset, 823 msg->msg_iov, used); 824 if (rc) { 825 /* Exception. Bailout! */ 826 if (!copied) 827 copied = -EFAULT; 828 break; 829 } 830 } 831 832 *seq += used; 833 copied += used; 834 len -= used; 835 836 /* For non stream protcols we get one packet per recvmsg call */ 837 if (sk->sk_type != SOCK_STREAM) 838 goto copy_uaddr; 839 840 if (!(flags & MSG_PEEK)) { 841 spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags); 842 sk_eat_skb(sk, skb, 0); 843 spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags); 844 *seq = 0; 845 } 846 847 /* Partial read */ 848 if (used + offset < skb->len) 849 continue; 850 } while (len > 0); 851 852out: 853 release_sock(sk); 854 return copied; 855copy_uaddr: 856 if (uaddr != NULL && skb != NULL) { 857 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr)); 858 msg->msg_namelen = sizeof(*uaddr); 859 } 860 if (llc_sk(sk)->cmsg_flags) 861 llc_cmsg_rcv(msg, skb); 862 863 if (!(flags & MSG_PEEK)) { 864 spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags); 865 sk_eat_skb(sk, skb, 0); 866 spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags); 867 *seq = 0; 868 } 869 870 goto out; 871} 872 873/** 874 * llc_ui_sendmsg - Transmit data provided by the socket user. 875 * @sock: Socket to transmit data from. 876 * @msg: Various user related information. 877 * @len: Length of data to transmit. 878 * 879 * Transmit data provided by the socket user. 880 * Returns non-negative upon success, negative otherwise. 881 */ 882static int llc_ui_sendmsg(struct kiocb *iocb, struct socket *sock, 883 struct msghdr *msg, size_t len) 884{ 885 struct sock *sk = sock->sk; 886 struct llc_sock *llc = llc_sk(sk); 887 struct sockaddr_llc *addr = (struct sockaddr_llc *)msg->msg_name; 888 int flags = msg->msg_flags; 889 int noblock = flags & MSG_DONTWAIT; 890 struct sk_buff *skb; 891 size_t size = 0; 892 int rc = -EINVAL, copied = 0, hdrlen; 893 894 dprintk("%s: sending from %02X to %02X\n", __func__, 895 llc->laddr.lsap, llc->daddr.lsap); 896 lock_sock(sk); 897 if (addr) { 898 if (msg->msg_namelen < sizeof(*addr)) 899 goto release; 900 } else { 901 if (llc_ui_addr_null(&llc->addr)) 902 goto release; 903 addr = &llc->addr; 904 } 905 /* must bind connection to sap if user hasn't done it. */ 906 if (sock_flag(sk, SOCK_ZAPPED)) { 907 /* bind to sap with null dev, exclusive. */ 908 rc = llc_ui_autobind(sock, addr); 909 if (rc) 910 goto release; 911 } 912 hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr); 913 size = hdrlen + len; 914 if (size > llc->dev->mtu) 915 size = llc->dev->mtu; 916 copied = size - hdrlen; 917 release_sock(sk); 918 skb = sock_alloc_send_skb(sk, size, noblock, &rc); 919 lock_sock(sk); 920 if (!skb) 921 goto release; 922 skb->dev = llc->dev; 923 skb->protocol = llc_proto_type(addr->sllc_arphrd); 924 skb_reserve(skb, hdrlen); 925 rc = memcpy_fromiovec(skb_put(skb, copied), msg->msg_iov, copied); 926 if (rc) 927 goto out; 928 if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) { 929 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac, 930 addr->sllc_sap); 931 goto out; 932 } 933 if (addr->sllc_test) { 934 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac, 935 addr->sllc_sap); 936 goto out; 937 } 938 if (addr->sllc_xid) { 939 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac, 940 addr->sllc_sap); 941 goto out; 942 } 943 rc = -ENOPROTOOPT; 944 if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua)) 945 goto out; 946 rc = llc_ui_send_data(sk, skb, noblock); 947out: 948 if (rc) { 949 kfree_skb(skb); 950release: 951 dprintk("%s: failed sending from %02X to %02X: %d\n", 952 __func__, llc->laddr.lsap, llc->daddr.lsap, rc); 953 } 954 release_sock(sk); 955 return rc ? : copied; 956} 957 958/** 959 * llc_ui_getname - return the address info of a socket 960 * @sock: Socket to get address of. 961 * @uaddr: Address structure to return information. 962 * @uaddrlen: Length of address structure. 963 * @peer: Does user want local or remote address information. 964 * 965 * Return the address information of a socket. 966 */ 967static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr, 968 int *uaddrlen, int peer) 969{ 970 struct sockaddr_llc sllc; 971 struct sock *sk = sock->sk; 972 struct llc_sock *llc = llc_sk(sk); 973 int rc = 0; 974 975 memset(&sllc, 0, sizeof(sllc)); 976 lock_sock(sk); 977 if (sock_flag(sk, SOCK_ZAPPED)) 978 goto out; 979 *uaddrlen = sizeof(sllc); 980 memset(uaddr, 0, *uaddrlen); 981 if (peer) { 982 rc = -ENOTCONN; 983 if (sk->sk_state != TCP_ESTABLISHED) 984 goto out; 985 if(llc->dev) 986 sllc.sllc_arphrd = llc->dev->type; 987 sllc.sllc_sap = llc->daddr.lsap; 988 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN); 989 } else { 990 rc = -EINVAL; 991 if (!llc->sap) 992 goto out; 993 sllc.sllc_sap = llc->sap->laddr.lsap; 994 995 if (llc->dev) { 996 sllc.sllc_arphrd = llc->dev->type; 997 memcpy(&sllc.sllc_mac, llc->dev->dev_addr, 998 IFHWADDRLEN); 999 } 1000 } 1001 rc = 0; 1002 sllc.sllc_family = AF_LLC; 1003 memcpy(uaddr, &sllc, sizeof(sllc)); 1004out: 1005 release_sock(sk); 1006 return rc; 1007} 1008 1009/** 1010 * llc_ui_ioctl - io controls for PF_LLC 1011 * @sock: Socket to get/set info 1012 * @cmd: command 1013 * @arg: optional argument for cmd 1014 * 1015 * get/set info on llc sockets 1016 */ 1017static int llc_ui_ioctl(struct socket *sock, unsigned int cmd, 1018 unsigned long arg) 1019{ 1020 return -ENOIOCTLCMD; 1021} 1022 1023/** 1024 * llc_ui_setsockopt - set various connection specific parameters. 1025 * @sock: Socket to set options on. 1026 * @level: Socket level user is requesting operations on. 1027 * @optname: Operation name. 1028 * @optval User provided operation data. 1029 * @optlen: Length of optval. 1030 * 1031 * Set various connection specific parameters. 1032 */ 1033static int llc_ui_setsockopt(struct socket *sock, int level, int optname, 1034 char __user *optval, unsigned int optlen) 1035{ 1036 struct sock *sk = sock->sk; 1037 struct llc_sock *llc = llc_sk(sk); 1038 unsigned int opt; 1039 int rc = -EINVAL; 1040 1041 lock_sock(sk); 1042 if (unlikely(level != SOL_LLC || optlen != sizeof(int))) 1043 goto out; 1044 rc = get_user(opt, (int __user *)optval); 1045 if (rc) 1046 goto out; 1047 rc = -EINVAL; 1048 switch (optname) { 1049 case LLC_OPT_RETRY: 1050 if (opt > LLC_OPT_MAX_RETRY) 1051 goto out; 1052 llc->n2 = opt; 1053 break; 1054 case LLC_OPT_SIZE: 1055 if (opt > LLC_OPT_MAX_SIZE) 1056 goto out; 1057 llc->n1 = opt; 1058 break; 1059 case LLC_OPT_ACK_TMR_EXP: 1060 if (opt > LLC_OPT_MAX_ACK_TMR_EXP) 1061 goto out; 1062 llc->ack_timer.expire = opt * HZ; 1063 break; 1064 case LLC_OPT_P_TMR_EXP: 1065 if (opt > LLC_OPT_MAX_P_TMR_EXP) 1066 goto out; 1067 llc->pf_cycle_timer.expire = opt * HZ; 1068 break; 1069 case LLC_OPT_REJ_TMR_EXP: 1070 if (opt > LLC_OPT_MAX_REJ_TMR_EXP) 1071 goto out; 1072 llc->rej_sent_timer.expire = opt * HZ; 1073 break; 1074 case LLC_OPT_BUSY_TMR_EXP: 1075 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP) 1076 goto out; 1077 llc->busy_state_timer.expire = opt * HZ; 1078 break; 1079 case LLC_OPT_TX_WIN: 1080 if (opt > LLC_OPT_MAX_WIN) 1081 goto out; 1082 llc->k = opt; 1083 break; 1084 case LLC_OPT_RX_WIN: 1085 if (opt > LLC_OPT_MAX_WIN) 1086 goto out; 1087 llc->rw = opt; 1088 break; 1089 case LLC_OPT_PKTINFO: 1090 if (opt) 1091 llc->cmsg_flags |= LLC_CMSG_PKTINFO; 1092 else 1093 llc->cmsg_flags &= ~LLC_CMSG_PKTINFO; 1094 break; 1095 default: 1096 rc = -ENOPROTOOPT; 1097 goto out; 1098 } 1099 rc = 0; 1100out: 1101 release_sock(sk); 1102 return rc; 1103} 1104 1105/** 1106 * llc_ui_getsockopt - get connection specific socket info 1107 * @sock: Socket to get information from. 1108 * @level: Socket level user is requesting operations on. 1109 * @optname: Operation name. 1110 * @optval: Variable to return operation data in. 1111 * @optlen: Length of optval. 1112 * 1113 * Get connection specific socket information. 1114 */ 1115static int llc_ui_getsockopt(struct socket *sock, int level, int optname, 1116 char __user *optval, int __user *optlen) 1117{ 1118 struct sock *sk = sock->sk; 1119 struct llc_sock *llc = llc_sk(sk); 1120 int val = 0, len = 0, rc = -EINVAL; 1121 1122 lock_sock(sk); 1123 if (unlikely(level != SOL_LLC)) 1124 goto out; 1125 rc = get_user(len, optlen); 1126 if (rc) 1127 goto out; 1128 rc = -EINVAL; 1129 if (len != sizeof(int)) 1130 goto out; 1131 switch (optname) { 1132 case LLC_OPT_RETRY: 1133 val = llc->n2; break; 1134 case LLC_OPT_SIZE: 1135 val = llc->n1; break; 1136 case LLC_OPT_ACK_TMR_EXP: 1137 val = llc->ack_timer.expire / HZ; break; 1138 case LLC_OPT_P_TMR_EXP: 1139 val = llc->pf_cycle_timer.expire / HZ; break; 1140 case LLC_OPT_REJ_TMR_EXP: 1141 val = llc->rej_sent_timer.expire / HZ; break; 1142 case LLC_OPT_BUSY_TMR_EXP: 1143 val = llc->busy_state_timer.expire / HZ; break; 1144 case LLC_OPT_TX_WIN: 1145 val = llc->k; break; 1146 case LLC_OPT_RX_WIN: 1147 val = llc->rw; break; 1148 case LLC_OPT_PKTINFO: 1149 val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0; 1150 break; 1151 default: 1152 rc = -ENOPROTOOPT; 1153 goto out; 1154 } 1155 rc = 0; 1156 if (put_user(len, optlen) || copy_to_user(optval, &val, len)) 1157 rc = -EFAULT; 1158out: 1159 release_sock(sk); 1160 return rc; 1161} 1162 1163static const struct net_proto_family llc_ui_family_ops = { 1164 .family = PF_LLC, 1165 .create = llc_ui_create, 1166 .owner = THIS_MODULE, 1167}; 1168 1169static const struct proto_ops llc_ui_ops = { 1170 .family = PF_LLC, 1171 .owner = THIS_MODULE, 1172 .release = llc_ui_release, 1173 .bind = llc_ui_bind, 1174 .connect = llc_ui_connect, 1175 .socketpair = sock_no_socketpair, 1176 .accept = llc_ui_accept, 1177 .getname = llc_ui_getname, 1178 .poll = datagram_poll, 1179 .ioctl = llc_ui_ioctl, 1180 .listen = llc_ui_listen, 1181 .shutdown = llc_ui_shutdown, 1182 .setsockopt = llc_ui_setsockopt, 1183 .getsockopt = llc_ui_getsockopt, 1184 .sendmsg = llc_ui_sendmsg, 1185 .recvmsg = llc_ui_recvmsg, 1186 .mmap = sock_no_mmap, 1187 .sendpage = sock_no_sendpage, 1188}; 1189 1190static const char llc_proc_err_msg[] __initconst = 1191 KERN_CRIT "LLC: Unable to register the proc_fs entries\n"; 1192static const char llc_sysctl_err_msg[] __initconst = 1193 KERN_CRIT "LLC: Unable to register the sysctl entries\n"; 1194static const char llc_sock_err_msg[] __initconst = 1195 KERN_CRIT "LLC: Unable to register the network family\n"; 1196 1197static int __init llc2_init(void) 1198{ 1199 int rc = proto_register(&llc_proto, 0); 1200 1201 if (rc != 0) 1202 goto out; 1203 1204 llc_build_offset_table(); 1205 llc_station_init(); 1206 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 1207 rc = llc_proc_init(); 1208 if (rc != 0) { 1209 printk(llc_proc_err_msg); 1210 goto out_unregister_llc_proto; 1211 } 1212 rc = llc_sysctl_init(); 1213 if (rc) { 1214 printk(llc_sysctl_err_msg); 1215 goto out_proc; 1216 } 1217 rc = sock_register(&llc_ui_family_ops); 1218 if (rc) { 1219 printk(llc_sock_err_msg); 1220 goto out_sysctl; 1221 } 1222 llc_add_pack(LLC_DEST_SAP, llc_sap_handler); 1223 llc_add_pack(LLC_DEST_CONN, llc_conn_handler); 1224out: 1225 return rc; 1226out_sysctl: 1227 llc_sysctl_exit(); 1228out_proc: 1229 llc_proc_exit(); 1230out_unregister_llc_proto: 1231 proto_unregister(&llc_proto); 1232 goto out; 1233} 1234 1235static void __exit llc2_exit(void) 1236{ 1237 llc_station_exit(); 1238 llc_remove_pack(LLC_DEST_SAP); 1239 llc_remove_pack(LLC_DEST_CONN); 1240 sock_unregister(PF_LLC); 1241 llc_proc_exit(); 1242 llc_sysctl_exit(); 1243 proto_unregister(&llc_proto); 1244} 1245 1246module_init(llc2_init); 1247module_exit(llc2_exit); 1248 1249MODULE_LICENSE("GPL"); 1250MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003"); 1251MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support"); 1252MODULE_ALIAS_NETPROTO(PF_LLC); 1253