af_llc.c revision 339db11b219f36cf7da61b390992d95bb6b7ba2e
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 rtnl_lock(); 320 if (sk->sk_bound_dev_if) { 321 llc->dev = dev_get_by_index(&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 dev_put(llc->dev); 333 llc->dev = NULL; 334 } 335 } 336 } else 337 llc->dev = dev_getbyhwaddr(&init_net, addr->sllc_arphrd, 338 addr->sllc_mac); 339 rtnl_unlock(); 340 if (!llc->dev) 341 goto out; 342 if (!addr->sllc_sap) { 343 rc = -EUSERS; 344 addr->sllc_sap = llc_ui_autoport(); 345 if (!addr->sllc_sap) 346 goto out; 347 } 348 sap = llc_sap_find(addr->sllc_sap); 349 if (!sap) { 350 sap = llc_sap_open(addr->sllc_sap, NULL); 351 rc = -EBUSY; /* some other network layer is using the sap */ 352 if (!sap) 353 goto out; 354 } else { 355 struct llc_addr laddr, daddr; 356 struct sock *ask; 357 358 memset(&laddr, 0, sizeof(laddr)); 359 memset(&daddr, 0, sizeof(daddr)); 360 /* 361 * FIXME: check if the address is multicast, 362 * only SOCK_DGRAM can do this. 363 */ 364 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN); 365 laddr.lsap = addr->sllc_sap; 366 rc = -EADDRINUSE; /* mac + sap clash. */ 367 ask = llc_lookup_established(sap, &daddr, &laddr); 368 if (ask) { 369 sock_put(ask); 370 goto out_put; 371 } 372 } 373 llc->laddr.lsap = addr->sllc_sap; 374 memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN); 375 memcpy(&llc->addr, addr, sizeof(llc->addr)); 376 /* assign new connection to its SAP */ 377 llc_sap_add_socket(sap, sk); 378 sock_reset_flag(sk, SOCK_ZAPPED); 379 rc = 0; 380out_put: 381 llc_sap_put(sap); 382out: 383 return rc; 384} 385 386/** 387 * llc_ui_shutdown - shutdown a connect llc2 socket. 388 * @sock: Socket to shutdown. 389 * @how: What part of the socket to shutdown. 390 * 391 * Shutdown a connected llc2 socket. Currently this function only supports 392 * shutting down both sends and receives (2), we could probably make this 393 * function such that a user can shutdown only half the connection but not 394 * right now. 395 * Returns: 0 upon success, negative otherwise. 396 */ 397static int llc_ui_shutdown(struct socket *sock, int how) 398{ 399 struct sock *sk = sock->sk; 400 int rc = -ENOTCONN; 401 402 lock_sock(sk); 403 if (unlikely(sk->sk_state != TCP_ESTABLISHED)) 404 goto out; 405 rc = -EINVAL; 406 if (how != 2) 407 goto out; 408 rc = llc_send_disc(sk); 409 if (!rc) 410 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo); 411 /* Wake up anyone sleeping in poll */ 412 sk->sk_state_change(sk); 413out: 414 release_sock(sk); 415 return rc; 416} 417 418/** 419 * llc_ui_connect - Connect to a remote llc2 mac + sap. 420 * @sock: Socket which will be connected to the remote destination. 421 * @uaddr: Remote and possibly the local address of the new connection. 422 * @addrlen: Size of uaddr structure. 423 * @flags: Operational flags specified by the user. 424 * 425 * Connect to a remote llc2 mac + sap. The caller must specify the 426 * destination mac and address to connect to. If the user hasn't previously 427 * called bind(2) with a smac the address of the first interface of the 428 * specified arp type will be used. 429 * This function will autobind if user did not previously call bind. 430 * Returns: 0 upon success, negative otherwise. 431 */ 432static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr, 433 int addrlen, int flags) 434{ 435 struct sock *sk = sock->sk; 436 struct llc_sock *llc = llc_sk(sk); 437 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr; 438 int rc = -EINVAL; 439 440 lock_sock(sk); 441 if (unlikely(addrlen != sizeof(*addr))) 442 goto out; 443 rc = -EAFNOSUPPORT; 444 if (unlikely(addr->sllc_family != AF_LLC)) 445 goto out; 446 if (unlikely(sk->sk_type != SOCK_STREAM)) 447 goto out; 448 rc = -EALREADY; 449 if (unlikely(sock->state == SS_CONNECTING)) 450 goto out; 451 /* bind connection to sap if user hasn't done it. */ 452 if (sock_flag(sk, SOCK_ZAPPED)) { 453 /* bind to sap with null dev, exclusive */ 454 rc = llc_ui_autobind(sock, addr); 455 if (rc) 456 goto out; 457 } 458 llc->daddr.lsap = addr->sllc_sap; 459 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN); 460 sock->state = SS_CONNECTING; 461 sk->sk_state = TCP_SYN_SENT; 462 llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap); 463 rc = llc_establish_connection(sk, llc->dev->dev_addr, 464 addr->sllc_mac, addr->sllc_sap); 465 if (rc) { 466 dprintk("%s: llc_ui_send_conn failed :-(\n", __func__); 467 sock->state = SS_UNCONNECTED; 468 sk->sk_state = TCP_CLOSE; 469 goto out; 470 } 471 472 if (sk->sk_state == TCP_SYN_SENT) { 473 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); 474 475 if (!timeo || !llc_ui_wait_for_conn(sk, timeo)) 476 goto out; 477 478 rc = sock_intr_errno(timeo); 479 if (signal_pending(current)) 480 goto out; 481 } 482 483 if (sk->sk_state == TCP_CLOSE) 484 goto sock_error; 485 486 sock->state = SS_CONNECTED; 487 rc = 0; 488out: 489 release_sock(sk); 490 return rc; 491sock_error: 492 rc = sock_error(sk) ? : -ECONNABORTED; 493 sock->state = SS_UNCONNECTED; 494 goto out; 495} 496 497/** 498 * llc_ui_listen - allow a normal socket to accept incoming connections 499 * @sock: Socket to allow incoming connections on. 500 * @backlog: Number of connections to queue. 501 * 502 * Allow a normal socket to accept incoming connections. 503 * Returns 0 upon success, negative otherwise. 504 */ 505static int llc_ui_listen(struct socket *sock, int backlog) 506{ 507 struct sock *sk = sock->sk; 508 int rc = -EINVAL; 509 510 lock_sock(sk); 511 if (unlikely(sock->state != SS_UNCONNECTED)) 512 goto out; 513 rc = -EOPNOTSUPP; 514 if (unlikely(sk->sk_type != SOCK_STREAM)) 515 goto out; 516 rc = -EAGAIN; 517 if (sock_flag(sk, SOCK_ZAPPED)) 518 goto out; 519 rc = 0; 520 if (!(unsigned)backlog) /* BSDism */ 521 backlog = 1; 522 sk->sk_max_ack_backlog = backlog; 523 if (sk->sk_state != TCP_LISTEN) { 524 sk->sk_ack_backlog = 0; 525 sk->sk_state = TCP_LISTEN; 526 } 527 sk->sk_socket->flags |= __SO_ACCEPTCON; 528out: 529 release_sock(sk); 530 return rc; 531} 532 533static int llc_ui_wait_for_disc(struct sock *sk, long timeout) 534{ 535 DEFINE_WAIT(wait); 536 int rc = 0; 537 538 while (1) { 539 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 540 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE)) 541 break; 542 rc = -ERESTARTSYS; 543 if (signal_pending(current)) 544 break; 545 rc = -EAGAIN; 546 if (!timeout) 547 break; 548 rc = 0; 549 } 550 finish_wait(sk_sleep(sk), &wait); 551 return rc; 552} 553 554static int llc_ui_wait_for_conn(struct sock *sk, long timeout) 555{ 556 DEFINE_WAIT(wait); 557 558 while (1) { 559 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 560 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT)) 561 break; 562 if (signal_pending(current) || !timeout) 563 break; 564 } 565 finish_wait(sk_sleep(sk), &wait); 566 return timeout; 567} 568 569static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout) 570{ 571 DEFINE_WAIT(wait); 572 struct llc_sock *llc = llc_sk(sk); 573 int rc; 574 575 while (1) { 576 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 577 rc = 0; 578 if (sk_wait_event(sk, &timeout, 579 (sk->sk_shutdown & RCV_SHUTDOWN) || 580 (!llc_data_accept_state(llc->state) && 581 !llc->remote_busy_flag && 582 !llc->p_flag))) 583 break; 584 rc = -ERESTARTSYS; 585 if (signal_pending(current)) 586 break; 587 rc = -EAGAIN; 588 if (!timeout) 589 break; 590 } 591 finish_wait(sk_sleep(sk), &wait); 592 return rc; 593} 594 595static int llc_wait_data(struct sock *sk, long timeo) 596{ 597 int rc; 598 599 while (1) { 600 /* 601 * POSIX 1003.1g mandates this order. 602 */ 603 rc = sock_error(sk); 604 if (rc) 605 break; 606 rc = 0; 607 if (sk->sk_shutdown & RCV_SHUTDOWN) 608 break; 609 rc = -EAGAIN; 610 if (!timeo) 611 break; 612 rc = sock_intr_errno(timeo); 613 if (signal_pending(current)) 614 break; 615 rc = 0; 616 if (sk_wait_data(sk, &timeo)) 617 break; 618 } 619 return rc; 620} 621 622static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb) 623{ 624 struct llc_sock *llc = llc_sk(skb->sk); 625 626 if (llc->cmsg_flags & LLC_CMSG_PKTINFO) { 627 struct llc_pktinfo info; 628 629 info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex; 630 llc_pdu_decode_dsap(skb, &info.lpi_sap); 631 llc_pdu_decode_da(skb, info.lpi_mac); 632 put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info); 633 } 634} 635 636/** 637 * llc_ui_accept - accept a new incoming connection. 638 * @sock: Socket which connections arrive on. 639 * @newsock: Socket to move incoming connection to. 640 * @flags: User specified operational flags. 641 * 642 * Accept a new incoming connection. 643 * Returns 0 upon success, negative otherwise. 644 */ 645static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags) 646{ 647 struct sock *sk = sock->sk, *newsk; 648 struct llc_sock *llc, *newllc; 649 struct sk_buff *skb; 650 int rc = -EOPNOTSUPP; 651 652 dprintk("%s: accepting on %02X\n", __func__, 653 llc_sk(sk)->laddr.lsap); 654 lock_sock(sk); 655 if (unlikely(sk->sk_type != SOCK_STREAM)) 656 goto out; 657 rc = -EINVAL; 658 if (unlikely(sock->state != SS_UNCONNECTED || 659 sk->sk_state != TCP_LISTEN)) 660 goto out; 661 /* wait for a connection to arrive. */ 662 if (skb_queue_empty(&sk->sk_receive_queue)) { 663 rc = llc_wait_data(sk, sk->sk_rcvtimeo); 664 if (rc) 665 goto out; 666 } 667 dprintk("%s: got a new connection on %02X\n", __func__, 668 llc_sk(sk)->laddr.lsap); 669 skb = skb_dequeue(&sk->sk_receive_queue); 670 rc = -EINVAL; 671 if (!skb->sk) 672 goto frees; 673 rc = 0; 674 newsk = skb->sk; 675 /* attach connection to a new socket. */ 676 llc_ui_sk_init(newsock, newsk); 677 sock_reset_flag(newsk, SOCK_ZAPPED); 678 newsk->sk_state = TCP_ESTABLISHED; 679 newsock->state = SS_CONNECTED; 680 llc = llc_sk(sk); 681 newllc = llc_sk(newsk); 682 memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr)); 683 newllc->link = llc_ui_next_link_no(newllc->laddr.lsap); 684 685 /* put original socket back into a clean listen state. */ 686 sk->sk_state = TCP_LISTEN; 687 sk->sk_ack_backlog--; 688 dprintk("%s: ok success on %02X, client on %02X\n", __func__, 689 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap); 690frees: 691 kfree_skb(skb); 692out: 693 release_sock(sk); 694 return rc; 695} 696 697/** 698 * llc_ui_recvmsg - copy received data to the socket user. 699 * @sock: Socket to copy data from. 700 * @msg: Various user space related information. 701 * @len: Size of user buffer. 702 * @flags: User specified flags. 703 * 704 * Copy received data to the socket user. 705 * Returns non-negative upon success, negative otherwise. 706 */ 707static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock, 708 struct msghdr *msg, size_t len, int flags) 709{ 710 struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name; 711 const int nonblock = flags & MSG_DONTWAIT; 712 struct sk_buff *skb = NULL; 713 struct sock *sk = sock->sk; 714 struct llc_sock *llc = llc_sk(sk); 715 size_t copied = 0; 716 u32 peek_seq = 0; 717 u32 *seq; 718 unsigned long used; 719 int target; /* Read at least this many bytes */ 720 long timeo; 721 722 lock_sock(sk); 723 copied = -ENOTCONN; 724 if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN)) 725 goto out; 726 727 timeo = sock_rcvtimeo(sk, nonblock); 728 729 seq = &llc->copied_seq; 730 if (flags & MSG_PEEK) { 731 peek_seq = llc->copied_seq; 732 seq = &peek_seq; 733 } 734 735 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 736 copied = 0; 737 738 do { 739 u32 offset; 740 741 /* 742 * We need to check signals first, to get correct SIGURG 743 * handling. FIXME: Need to check this doesn't impact 1003.1g 744 * and move it down to the bottom of the loop 745 */ 746 if (signal_pending(current)) { 747 if (copied) 748 break; 749 copied = timeo ? sock_intr_errno(timeo) : -EAGAIN; 750 break; 751 } 752 753 /* Next get a buffer. */ 754 755 skb = skb_peek(&sk->sk_receive_queue); 756 if (skb) { 757 offset = *seq; 758 goto found_ok_skb; 759 } 760 /* Well, if we have backlog, try to process it now yet. */ 761 762 if (copied >= target && !sk->sk_backlog.tail) 763 break; 764 765 if (copied) { 766 if (sk->sk_err || 767 sk->sk_state == TCP_CLOSE || 768 (sk->sk_shutdown & RCV_SHUTDOWN) || 769 !timeo || 770 (flags & MSG_PEEK)) 771 break; 772 } else { 773 if (sock_flag(sk, SOCK_DONE)) 774 break; 775 776 if (sk->sk_err) { 777 copied = sock_error(sk); 778 break; 779 } 780 if (sk->sk_shutdown & RCV_SHUTDOWN) 781 break; 782 783 if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) { 784 if (!sock_flag(sk, SOCK_DONE)) { 785 /* 786 * This occurs when user tries to read 787 * from never connected socket. 788 */ 789 copied = -ENOTCONN; 790 break; 791 } 792 break; 793 } 794 if (!timeo) { 795 copied = -EAGAIN; 796 break; 797 } 798 } 799 800 if (copied >= target) { /* Do not sleep, just process backlog. */ 801 release_sock(sk); 802 lock_sock(sk); 803 } else 804 sk_wait_data(sk, &timeo); 805 806 if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) { 807 if (net_ratelimit()) 808 printk(KERN_DEBUG "LLC(%s:%d): Application " 809 "bug, race in MSG_PEEK.\n", 810 current->comm, task_pid_nr(current)); 811 peek_seq = llc->copied_seq; 812 } 813 continue; 814 found_ok_skb: 815 /* Ok so how much can we use? */ 816 used = skb->len - offset; 817 if (len < used) 818 used = len; 819 820 if (!(flags & MSG_TRUNC)) { 821 int rc = skb_copy_datagram_iovec(skb, offset, 822 msg->msg_iov, used); 823 if (rc) { 824 /* Exception. Bailout! */ 825 if (!copied) 826 copied = -EFAULT; 827 break; 828 } 829 } 830 831 *seq += used; 832 copied += used; 833 len -= used; 834 835 if (!(flags & MSG_PEEK)) { 836 sk_eat_skb(sk, skb, 0); 837 *seq = 0; 838 } 839 840 /* For non stream protcols we get one packet per recvmsg call */ 841 if (sk->sk_type != SOCK_STREAM) 842 goto copy_uaddr; 843 844 /* Partial read */ 845 if (used + offset < skb->len) 846 continue; 847 } while (len > 0); 848 849out: 850 release_sock(sk); 851 return copied; 852copy_uaddr: 853 if (uaddr != NULL && skb != NULL) { 854 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr)); 855 msg->msg_namelen = sizeof(*uaddr); 856 } 857 if (llc_sk(sk)->cmsg_flags) 858 llc_cmsg_rcv(msg, skb); 859 goto out; 860} 861 862/** 863 * llc_ui_sendmsg - Transmit data provided by the socket user. 864 * @sock: Socket to transmit data from. 865 * @msg: Various user related information. 866 * @len: Length of data to transmit. 867 * 868 * Transmit data provided by the socket user. 869 * Returns non-negative upon success, negative otherwise. 870 */ 871static int llc_ui_sendmsg(struct kiocb *iocb, struct socket *sock, 872 struct msghdr *msg, size_t len) 873{ 874 struct sock *sk = sock->sk; 875 struct llc_sock *llc = llc_sk(sk); 876 struct sockaddr_llc *addr = (struct sockaddr_llc *)msg->msg_name; 877 int flags = msg->msg_flags; 878 int noblock = flags & MSG_DONTWAIT; 879 struct sk_buff *skb; 880 size_t size = 0; 881 int rc = -EINVAL, copied = 0, hdrlen; 882 883 dprintk("%s: sending from %02X to %02X\n", __func__, 884 llc->laddr.lsap, llc->daddr.lsap); 885 lock_sock(sk); 886 if (addr) { 887 if (msg->msg_namelen < sizeof(*addr)) 888 goto release; 889 } else { 890 if (llc_ui_addr_null(&llc->addr)) 891 goto release; 892 addr = &llc->addr; 893 } 894 /* must bind connection to sap if user hasn't done it. */ 895 if (sock_flag(sk, SOCK_ZAPPED)) { 896 /* bind to sap with null dev, exclusive. */ 897 rc = llc_ui_autobind(sock, addr); 898 if (rc) 899 goto release; 900 } 901 hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr); 902 size = hdrlen + len; 903 if (size > llc->dev->mtu) 904 size = llc->dev->mtu; 905 copied = size - hdrlen; 906 release_sock(sk); 907 skb = sock_alloc_send_skb(sk, size, noblock, &rc); 908 lock_sock(sk); 909 if (!skb) 910 goto release; 911 skb->dev = llc->dev; 912 skb->protocol = llc_proto_type(addr->sllc_arphrd); 913 skb_reserve(skb, hdrlen); 914 rc = memcpy_fromiovec(skb_put(skb, copied), msg->msg_iov, copied); 915 if (rc) 916 goto out; 917 if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) { 918 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac, 919 addr->sllc_sap); 920 goto out; 921 } 922 if (addr->sllc_test) { 923 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac, 924 addr->sllc_sap); 925 goto out; 926 } 927 if (addr->sllc_xid) { 928 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac, 929 addr->sllc_sap); 930 goto out; 931 } 932 rc = -ENOPROTOOPT; 933 if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua)) 934 goto out; 935 rc = llc_ui_send_data(sk, skb, noblock); 936out: 937 if (rc) { 938 kfree_skb(skb); 939release: 940 dprintk("%s: failed sending from %02X to %02X: %d\n", 941 __func__, llc->laddr.lsap, llc->daddr.lsap, rc); 942 } 943 release_sock(sk); 944 return rc ? : copied; 945} 946 947/** 948 * llc_ui_getname - return the address info of a socket 949 * @sock: Socket to get address of. 950 * @uaddr: Address structure to return information. 951 * @uaddrlen: Length of address structure. 952 * @peer: Does user want local or remote address information. 953 * 954 * Return the address information of a socket. 955 */ 956static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr, 957 int *uaddrlen, int peer) 958{ 959 struct sockaddr_llc sllc; 960 struct sock *sk = sock->sk; 961 struct llc_sock *llc = llc_sk(sk); 962 int rc = 0; 963 964 memset(&sllc, 0, sizeof(sllc)); 965 lock_sock(sk); 966 if (sock_flag(sk, SOCK_ZAPPED)) 967 goto out; 968 *uaddrlen = sizeof(sllc); 969 memset(uaddr, 0, *uaddrlen); 970 if (peer) { 971 rc = -ENOTCONN; 972 if (sk->sk_state != TCP_ESTABLISHED) 973 goto out; 974 if(llc->dev) 975 sllc.sllc_arphrd = llc->dev->type; 976 sllc.sllc_sap = llc->daddr.lsap; 977 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN); 978 } else { 979 rc = -EINVAL; 980 if (!llc->sap) 981 goto out; 982 sllc.sllc_sap = llc->sap->laddr.lsap; 983 984 if (llc->dev) { 985 sllc.sllc_arphrd = llc->dev->type; 986 memcpy(&sllc.sllc_mac, llc->dev->dev_addr, 987 IFHWADDRLEN); 988 } 989 } 990 rc = 0; 991 sllc.sllc_family = AF_LLC; 992 memcpy(uaddr, &sllc, sizeof(sllc)); 993out: 994 release_sock(sk); 995 return rc; 996} 997 998/** 999 * llc_ui_ioctl - io controls for PF_LLC 1000 * @sock: Socket to get/set info 1001 * @cmd: command 1002 * @arg: optional argument for cmd 1003 * 1004 * get/set info on llc sockets 1005 */ 1006static int llc_ui_ioctl(struct socket *sock, unsigned int cmd, 1007 unsigned long arg) 1008{ 1009 return -ENOIOCTLCMD; 1010} 1011 1012/** 1013 * llc_ui_setsockopt - set various connection specific parameters. 1014 * @sock: Socket to set options on. 1015 * @level: Socket level user is requesting operations on. 1016 * @optname: Operation name. 1017 * @optval User provided operation data. 1018 * @optlen: Length of optval. 1019 * 1020 * Set various connection specific parameters. 1021 */ 1022static int llc_ui_setsockopt(struct socket *sock, int level, int optname, 1023 char __user *optval, unsigned int optlen) 1024{ 1025 struct sock *sk = sock->sk; 1026 struct llc_sock *llc = llc_sk(sk); 1027 unsigned int opt; 1028 int rc = -EINVAL; 1029 1030 lock_sock(sk); 1031 if (unlikely(level != SOL_LLC || optlen != sizeof(int))) 1032 goto out; 1033 rc = get_user(opt, (int __user *)optval); 1034 if (rc) 1035 goto out; 1036 rc = -EINVAL; 1037 switch (optname) { 1038 case LLC_OPT_RETRY: 1039 if (opt > LLC_OPT_MAX_RETRY) 1040 goto out; 1041 llc->n2 = opt; 1042 break; 1043 case LLC_OPT_SIZE: 1044 if (opt > LLC_OPT_MAX_SIZE) 1045 goto out; 1046 llc->n1 = opt; 1047 break; 1048 case LLC_OPT_ACK_TMR_EXP: 1049 if (opt > LLC_OPT_MAX_ACK_TMR_EXP) 1050 goto out; 1051 llc->ack_timer.expire = opt * HZ; 1052 break; 1053 case LLC_OPT_P_TMR_EXP: 1054 if (opt > LLC_OPT_MAX_P_TMR_EXP) 1055 goto out; 1056 llc->pf_cycle_timer.expire = opt * HZ; 1057 break; 1058 case LLC_OPT_REJ_TMR_EXP: 1059 if (opt > LLC_OPT_MAX_REJ_TMR_EXP) 1060 goto out; 1061 llc->rej_sent_timer.expire = opt * HZ; 1062 break; 1063 case LLC_OPT_BUSY_TMR_EXP: 1064 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP) 1065 goto out; 1066 llc->busy_state_timer.expire = opt * HZ; 1067 break; 1068 case LLC_OPT_TX_WIN: 1069 if (opt > LLC_OPT_MAX_WIN) 1070 goto out; 1071 llc->k = opt; 1072 break; 1073 case LLC_OPT_RX_WIN: 1074 if (opt > LLC_OPT_MAX_WIN) 1075 goto out; 1076 llc->rw = opt; 1077 break; 1078 case LLC_OPT_PKTINFO: 1079 if (opt) 1080 llc->cmsg_flags |= LLC_CMSG_PKTINFO; 1081 else 1082 llc->cmsg_flags &= ~LLC_CMSG_PKTINFO; 1083 break; 1084 default: 1085 rc = -ENOPROTOOPT; 1086 goto out; 1087 } 1088 rc = 0; 1089out: 1090 release_sock(sk); 1091 return rc; 1092} 1093 1094/** 1095 * llc_ui_getsockopt - get connection specific socket info 1096 * @sock: Socket to get information from. 1097 * @level: Socket level user is requesting operations on. 1098 * @optname: Operation name. 1099 * @optval: Variable to return operation data in. 1100 * @optlen: Length of optval. 1101 * 1102 * Get connection specific socket information. 1103 */ 1104static int llc_ui_getsockopt(struct socket *sock, int level, int optname, 1105 char __user *optval, int __user *optlen) 1106{ 1107 struct sock *sk = sock->sk; 1108 struct llc_sock *llc = llc_sk(sk); 1109 int val = 0, len = 0, rc = -EINVAL; 1110 1111 lock_sock(sk); 1112 if (unlikely(level != SOL_LLC)) 1113 goto out; 1114 rc = get_user(len, optlen); 1115 if (rc) 1116 goto out; 1117 rc = -EINVAL; 1118 if (len != sizeof(int)) 1119 goto out; 1120 switch (optname) { 1121 case LLC_OPT_RETRY: 1122 val = llc->n2; break; 1123 case LLC_OPT_SIZE: 1124 val = llc->n1; break; 1125 case LLC_OPT_ACK_TMR_EXP: 1126 val = llc->ack_timer.expire / HZ; break; 1127 case LLC_OPT_P_TMR_EXP: 1128 val = llc->pf_cycle_timer.expire / HZ; break; 1129 case LLC_OPT_REJ_TMR_EXP: 1130 val = llc->rej_sent_timer.expire / HZ; break; 1131 case LLC_OPT_BUSY_TMR_EXP: 1132 val = llc->busy_state_timer.expire / HZ; break; 1133 case LLC_OPT_TX_WIN: 1134 val = llc->k; break; 1135 case LLC_OPT_RX_WIN: 1136 val = llc->rw; break; 1137 case LLC_OPT_PKTINFO: 1138 val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0; 1139 break; 1140 default: 1141 rc = -ENOPROTOOPT; 1142 goto out; 1143 } 1144 rc = 0; 1145 if (put_user(len, optlen) || copy_to_user(optval, &val, len)) 1146 rc = -EFAULT; 1147out: 1148 release_sock(sk); 1149 return rc; 1150} 1151 1152static const struct net_proto_family llc_ui_family_ops = { 1153 .family = PF_LLC, 1154 .create = llc_ui_create, 1155 .owner = THIS_MODULE, 1156}; 1157 1158static const struct proto_ops llc_ui_ops = { 1159 .family = PF_LLC, 1160 .owner = THIS_MODULE, 1161 .release = llc_ui_release, 1162 .bind = llc_ui_bind, 1163 .connect = llc_ui_connect, 1164 .socketpair = sock_no_socketpair, 1165 .accept = llc_ui_accept, 1166 .getname = llc_ui_getname, 1167 .poll = datagram_poll, 1168 .ioctl = llc_ui_ioctl, 1169 .listen = llc_ui_listen, 1170 .shutdown = llc_ui_shutdown, 1171 .setsockopt = llc_ui_setsockopt, 1172 .getsockopt = llc_ui_getsockopt, 1173 .sendmsg = llc_ui_sendmsg, 1174 .recvmsg = llc_ui_recvmsg, 1175 .mmap = sock_no_mmap, 1176 .sendpage = sock_no_sendpage, 1177}; 1178 1179static const char llc_proc_err_msg[] __initconst = 1180 KERN_CRIT "LLC: Unable to register the proc_fs entries\n"; 1181static const char llc_sysctl_err_msg[] __initconst = 1182 KERN_CRIT "LLC: Unable to register the sysctl entries\n"; 1183static const char llc_sock_err_msg[] __initconst = 1184 KERN_CRIT "LLC: Unable to register the network family\n"; 1185 1186static int __init llc2_init(void) 1187{ 1188 int rc = proto_register(&llc_proto, 0); 1189 1190 if (rc != 0) 1191 goto out; 1192 1193 llc_build_offset_table(); 1194 llc_station_init(); 1195 llc_ui_sap_last_autoport = LLC_SAP_DYN_START; 1196 rc = llc_proc_init(); 1197 if (rc != 0) { 1198 printk(llc_proc_err_msg); 1199 goto out_unregister_llc_proto; 1200 } 1201 rc = llc_sysctl_init(); 1202 if (rc) { 1203 printk(llc_sysctl_err_msg); 1204 goto out_proc; 1205 } 1206 rc = sock_register(&llc_ui_family_ops); 1207 if (rc) { 1208 printk(llc_sock_err_msg); 1209 goto out_sysctl; 1210 } 1211 llc_add_pack(LLC_DEST_SAP, llc_sap_handler); 1212 llc_add_pack(LLC_DEST_CONN, llc_conn_handler); 1213out: 1214 return rc; 1215out_sysctl: 1216 llc_sysctl_exit(); 1217out_proc: 1218 llc_proc_exit(); 1219out_unregister_llc_proto: 1220 proto_unregister(&llc_proto); 1221 goto out; 1222} 1223 1224static void __exit llc2_exit(void) 1225{ 1226 llc_station_exit(); 1227 llc_remove_pack(LLC_DEST_SAP); 1228 llc_remove_pack(LLC_DEST_CONN); 1229 sock_unregister(PF_LLC); 1230 llc_proc_exit(); 1231 llc_sysctl_exit(); 1232 proto_unregister(&llc_proto); 1233} 1234 1235module_init(llc2_init); 1236module_exit(llc2_exit); 1237 1238MODULE_LICENSE("GPL"); 1239MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003"); 1240MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support"); 1241MODULE_ALIAS_NETPROTO(PF_LLC); 1242