net/rxrpc/af_rxrpc.c

   1 /* AF_RXRPC implementation
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/module.h>
  15 #include <linux/kernel.h>
  16 #include <linux/net.h>
  17 #include <linux/slab.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/random.h>
  20 #include <linux/poll.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/key-type.h>
  23 #include <net/net_namespace.h>
  24 #include <net/sock.h>
  25 #include <net/af_rxrpc.h>
  26 #define CREATE_TRACE_POINTS
  27 #include "ar-internal.h"
  28
  29 MODULE_DESCRIPTION("RxRPC network protocol");
  30 MODULE_AUTHOR("Red Hat, Inc.");
  31 MODULE_LICENSE("GPL");
  32 MODULE_ALIAS_NETPROTO(PF_RXRPC);
  33
  34 unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
  35 module_param_named(debug, rxrpc_debug, uint, S_IWUSR | S_IRUGO);
  36 MODULE_PARM_DESC(debug, "RxRPC debugging mask");
  37
  38 static struct proto rxrpc_proto;
  39 static const struct proto_ops rxrpc_rpc_ops;
  40
  41 /* current debugging ID */
  42 atomic_t rxrpc_debug_id;
  43
  44 /* count of skbs currently in use */
  45 atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_skbs;
  46
  47 struct workqueue_struct *rxrpc_workqueue;
  48
  49 static void rxrpc_sock_destructor(struct sock *);
  50
  51 /*
  52  * see if an RxRPC socket is currently writable
  53  */
  54 static inline int rxrpc_writable(struct sock *sk)
  55 {
  56         return refcount_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
  57 }
  58
  59 /*
  60  * wait for write bufferage to become available
  61  */
  62 static void rxrpc_write_space(struct sock *sk)
  63 {
  64         _enter("%p", sk);
  65         rcu_read_lock();
  66         if (rxrpc_writable(sk)) {
  67                 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
  68
  69                 if (skwq_has_sleeper(wq))
  70                         wake_up_interruptible(&wq->wait);
  71                 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
  72         }
  73         rcu_read_unlock();
  74 }
  75
  76 /*
  77  * validate an RxRPC address
  78  */
  79 static int rxrpc_validate_address(struct rxrpc_sock *rx,
  80                                   struct sockaddr_rxrpc *srx,
  81                                   int len)
  82 {
  83         unsigned int tail;
  84
  85         if (len < sizeof(struct sockaddr_rxrpc))
  86                 return -EINVAL;
  87
  88         if (srx->srx_family != AF_RXRPC)
  89                 return -EAFNOSUPPORT;
  90
  91         if (srx->transport_type != SOCK_DGRAM)
  92                 return -ESOCKTNOSUPPORT;
  93
  94         len -= offsetof(struct sockaddr_rxrpc, transport);
  95         if (srx->transport_len < sizeof(sa_family_t) ||
  96             srx->transport_len > len)
  97                 return -EINVAL;
  98
  99         if (srx->transport.family != rx->family)
 100                 return -EAFNOSUPPORT;
 101
 102         switch (srx->transport.family) {
 103         case AF_INET:
 104                 if (srx->transport_len < sizeof(struct sockaddr_in))
 105                         return -EINVAL;
 106                 tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
 107                 break;
 108
 109 #ifdef CONFIG_AF_RXRPC_IPV6
 110         case AF_INET6:
 111                 if (srx->transport_len < sizeof(struct sockaddr_in6))
 112                         return -EINVAL;
 113                 tail = offsetof(struct sockaddr_rxrpc, transport) +
 114                         sizeof(struct sockaddr_in6);
 115                 break;
 116 #endif
 117
 118         default:
 119                 return -EAFNOSUPPORT;
 120         }
 121
 122         if (tail < len)
 123                 memset((void *)srx + tail, 0, len - tail);
 124         _debug("INET: %pISp", &srx->transport);
 125         return 0;
 126 }
 127
 128 /*
 129  * bind a local address to an RxRPC socket
 130  */
 131 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
 132 {
 133         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
 134         struct rxrpc_local *local;
 135         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 136         u16 service_id = srx->srx_service;
 137         int ret;
 138
 139         _enter("%p,%p,%d", rx, saddr, len);
 140
 141         ret = rxrpc_validate_address(rx, srx, len);
 142         if (ret < 0)
 143                 goto error;
 144
 145         lock_sock(&rx->sk);
 146
 147         switch (rx->sk.sk_state) {
 148         case RXRPC_UNBOUND:
 149                 rx->srx = *srx;
 150                 local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
 151                 if (IS_ERR(local)) {
 152                         ret = PTR_ERR(local);
 153                         goto error_unlock;
 154                 }
 155
 156                 if (service_id) {
 157                         write_lock(&local->services_lock);
 158                         if (rcu_access_pointer(local->service))
 159                                 goto service_in_use;
 160                         rx->local = local;
 161                         rcu_assign_pointer(local->service, rx);
 162                         write_unlock(&local->services_lock);
 163
 164                         rx->sk.sk_state = RXRPC_SERVER_BOUND;
 165                 } else {
 166                         rx->local = local;
 167                         rx->sk.sk_state = RXRPC_CLIENT_BOUND;
 168                 }
 169                 break;
 170
 171         case RXRPC_SERVER_BOUND:
 172                 ret = -EINVAL;
 173                 if (service_id == 0)
 174                         goto error_unlock;
 175                 ret = -EADDRINUSE;
 176                 if (service_id == rx->srx.srx_service)
 177                         goto error_unlock;
 178                 ret = -EINVAL;
 179                 srx->srx_service = rx->srx.srx_service;
 180                 if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0)
 181                         goto error_unlock;
 182                 rx->second_service = service_id;
 183                 rx->sk.sk_state = RXRPC_SERVER_BOUND2;
 184                 break;
 185
 186         default:
 187                 ret = -EINVAL;
 188                 goto error_unlock;
 189         }
 190
 191         release_sock(&rx->sk);
 192         _leave(" = 0");
 193         return 0;
 194
 195 service_in_use:
 196         write_unlock(&local->services_lock);
 197         rxrpc_put_local(local);
 198         ret = -EADDRINUSE;
 199 error_unlock:
 200         release_sock(&rx->sk);
 201 error:
 202         _leave(" = %d", ret);
 203         return ret;
 204 }
 205
 206 /*
 207  * set the number of pending calls permitted on a listening socket
 208  */
 209 static int rxrpc_listen(struct socket *sock, int backlog)
 210 {
 211         struct sock *sk = sock->sk;
 212         struct rxrpc_sock *rx = rxrpc_sk(sk);
 213         unsigned int max, old;
 214         int ret;
 215
 216         _enter("%p,%d", rx, backlog);
 217
 218         lock_sock(&rx->sk);
 219
 220         switch (rx->sk.sk_state) {
 221         case RXRPC_UNBOUND:
 222                 ret = -EADDRNOTAVAIL;
 223                 break;
 224         case RXRPC_SERVER_BOUND:
 225         case RXRPC_SERVER_BOUND2:
 226                 ASSERT(rx->local != NULL);
 227                 max = READ_ONCE(rxrpc_max_backlog);
 228                 ret = -EINVAL;
 229                 if (backlog == INT_MAX)
 230                         backlog = max;
 231                 else if (backlog < 0 || backlog > max)
 232                         break;
 233                 old = sk->sk_max_ack_backlog;
 234                 sk->sk_max_ack_backlog = backlog;
 235                 ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
 236                 if (ret == 0)
 237                         rx->sk.sk_state = RXRPC_SERVER_LISTENING;
 238                 else
 239                         sk->sk_max_ack_backlog = old;
 240                 break;
 241         case RXRPC_SERVER_LISTENING:
 242                 if (backlog == 0) {
 243                         rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED;
 244                         sk->sk_max_ack_backlog = 0;
 245                         rxrpc_discard_prealloc(rx);
 246                         ret = 0;
 247                         break;
 248                 }
 249                 /* Fall through */
 250         default:
 251                 ret = -EBUSY;
 252                 break;
 253         }
 254
 255         release_sock(&rx->sk);
 256         _leave(" = %d", ret);
 257         return ret;
 258 }
 259
 260 /**
 261  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
 262  * @sock: The socket on which to make the call
 263  * @srx: The address of the peer to contact
 264  * @key: The security context to use (defaults to socket setting)
 265  * @user_call_ID: The ID to use
 266  * @tx_total_len: Total length of data to transmit during the call (or -1)
 267  * @gfp: The allocation constraints
 268  * @notify_rx: Where to send notifications instead of socket queue
 269  * @upgrade: Request service upgrade for call
 270  *
 271  * Allow a kernel service to begin a call on the nominated socket.  This just
 272  * sets up all the internal tracking structures and allocates connection and
 273  * call IDs as appropriate.  The call to be used is returned.
 274  *
 275  * The default socket destination address and security may be overridden by
 276  * supplying @srx and @key.
 277  */
 278 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 279                                            struct sockaddr_rxrpc *srx,
 280                                            struct key *key,
 281                                            unsigned long user_call_ID,
 282                                            s64 tx_total_len,
 283                                            gfp_t gfp,
 284                                            rxrpc_notify_rx_t notify_rx,
 285                                            bool upgrade)
 286 {
 287         struct rxrpc_conn_parameters cp;
 288         struct rxrpc_call *call;
 289         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 290         int ret;
 291
 292         _enter(",,%x,%lx", key_serial(key), user_call_ID);
 293
 294         ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
 295         if (ret < 0)
 296                 return ERR_PTR(ret);
 297
 298         lock_sock(&rx->sk);
 299
 300         if (!key)
 301                 key = rx->key;
 302         if (key && !key->payload.data[0])
 303                 key = NULL; /* a no-security key */
 304
 305         memset(&cp, 0, sizeof(cp));
 306         cp.local                = rx->local;
 307         cp.key                  = key;
 308         cp.security_level       = 0;
 309         cp.exclusive            = false;
 310         cp.upgrade              = upgrade;
 311         cp.service_id           = srx->srx_service;
 312         call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, tx_total_len,
 313                                      gfp);
 314         /* The socket has been unlocked. */
 315         if (!IS_ERR(call)) {
 316                 call->notify_rx = notify_rx;
 317                 mutex_unlock(&call->user_mutex);
 318         }
 319
 320         _leave(" = %p", call);
 321         return call;
 322 }
 323 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
 324
 325 /*
 326  * Dummy function used to stop the notifier talking to recvmsg().
 327  */
 328 static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall,
 329                                   unsigned long call_user_ID)
 330 {
 331 }
 332
 333 /**
 334  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
 335  * @sock: The socket the call is on
 336  * @call: The call to end
 337  *
 338  * Allow a kernel service to end a call it was using.  The call must be
 339  * complete before this is called (the call should be aborted if necessary).
 340  */
 341 void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
 342 {
 343         _enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
 344
 345         mutex_lock(&call->user_mutex);
 346         rxrpc_release_call(rxrpc_sk(sock->sk), call);
 347
 348         /* Make sure we're not going to call back into a kernel service */
 349         if (call->notify_rx) {
 350                 spin_lock_bh(&call->notify_lock);
 351                 call->notify_rx = rxrpc_dummy_notify_rx;
 352                 spin_unlock_bh(&call->notify_lock);
 353         }
 354
 355         mutex_unlock(&call->user_mutex);
 356         rxrpc_put_call(call, rxrpc_call_put_kernel);
 357 }
 358 EXPORT_SYMBOL(rxrpc_kernel_end_call);
 359
 360 /**
 361  * rxrpc_kernel_check_life - Check to see whether a call is still alive
 362  * @sock: The socket the call is on
 363  * @call: The call to check
 364  *
 365  * Allow a kernel service to find out whether a call is still alive - ie. we're
 366  * getting ACKs from the server.  Returns a number representing the life state
 367  * which can be compared to that returned by a previous call.
 368  *
 369  * If this is a client call, ping ACKs will be sent to the server to find out
 370  * whether it's still responsive and whether the call is still alive on the
 371  * server.
 372  */
 373 u32 rxrpc_kernel_check_life(struct socket *sock, struct rxrpc_call *call)
 374 {
 375         return call->acks_latest;
 376 }
 377 EXPORT_SYMBOL(rxrpc_kernel_check_life);
 378
 379 /**
 380  * rxrpc_kernel_check_call - Check a call's state
 381  * @sock: The socket the call is on
 382  * @call: The call to check
 383  * @_compl: Where to store the completion state
 384  * @_abort_code: Where to store any abort code
 385  *
 386  * Allow a kernel service to query the state of a call and find out the manner
 387  * of its termination if it has completed.  Returns -EINPROGRESS if the call is
 388  * still going, 0 if the call finished successfully, -ECONNABORTED if the call
 389  * was aborted and an appropriate error if the call failed in some other way.
 390  */
 391 int rxrpc_kernel_check_call(struct socket *sock, struct rxrpc_call *call,
 392                             enum rxrpc_call_completion *_compl, u32 *_abort_code)
 393 {
 394         if (call->state != RXRPC_CALL_COMPLETE)
 395                 return -EINPROGRESS;
 396         smp_rmb();
 397         *_compl = call->completion;
 398         *_abort_code = call->abort_code;
 399         return call->error;
 400 }
 401 EXPORT_SYMBOL(rxrpc_kernel_check_call);
 402
 403 /**
 404  * rxrpc_kernel_retry_call - Allow a kernel service to retry a call
 405  * @sock: The socket the call is on
 406  * @call: The call to retry
 407  * @srx: The address of the peer to contact
 408  * @key: The security context to use (defaults to socket setting)
 409  *
 410  * Allow a kernel service to try resending a client call that failed due to a
 411  * network error to a new address.  The Tx queue is maintained intact, thereby
 412  * relieving the need to re-encrypt any request data that has already been
 413  * buffered.
 414  */
 415 int rxrpc_kernel_retry_call(struct socket *sock, struct rxrpc_call *call,
 416                             struct sockaddr_rxrpc *srx, struct key *key)
 417 {
 418         struct rxrpc_conn_parameters cp;
 419         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 420         int ret;
 421
 422         _enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
 423
 424         if (!key)
 425                 key = rx->key;
 426         if (key && !key->payload.data[0])
 427                 key = NULL; /* a no-security key */
 428
 429         memset(&cp, 0, sizeof(cp));
 430         cp.local                = rx->local;
 431         cp.key                  = key;
 432         cp.security_level       = 0;
 433         cp.exclusive            = false;
 434         cp.service_id           = srx->srx_service;
 435
 436         mutex_lock(&call->user_mutex);
 437
 438         ret = rxrpc_prepare_call_for_retry(rx, call);
 439         if (ret == 0)
 440                 ret = rxrpc_retry_client_call(rx, call, &cp, srx, GFP_KERNEL);
 441
 442         mutex_unlock(&call->user_mutex);
 443         _leave(" = %d", ret);
 444         return ret;
 445 }
 446 EXPORT_SYMBOL(rxrpc_kernel_retry_call);
 447
 448 /**
 449  * rxrpc_kernel_new_call_notification - Get notifications of new calls
 450  * @sock: The socket to intercept received messages on
 451  * @notify_new_call: Function to be called when new calls appear
 452  * @discard_new_call: Function to discard preallocated calls
 453  *
 454  * Allow a kernel service to be given notifications about new calls.
 455  */
 456 void rxrpc_kernel_new_call_notification(
 457         struct socket *sock,
 458         rxrpc_notify_new_call_t notify_new_call,
 459         rxrpc_discard_new_call_t discard_new_call)
 460 {
 461         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 462
 463         rx->notify_new_call = notify_new_call;
 464         rx->discard_new_call = discard_new_call;
 465 }
 466 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
 467
 468 /*
 469  * connect an RxRPC socket
 470  * - this just targets it at a specific destination; no actual connection
 471  *   negotiation takes place
 472  */
 473 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
 474                          int addr_len, int flags)
 475 {
 476         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
 477         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 478         int ret;
 479
 480         _enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
 481
 482         ret = rxrpc_validate_address(rx, srx, addr_len);
 483         if (ret < 0) {
 484                 _leave(" = %d [bad addr]", ret);
 485                 return ret;
 486         }
 487
 488         lock_sock(&rx->sk);
 489
 490         ret = -EISCONN;
 491         if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
 492                 goto error;
 493
 494         switch (rx->sk.sk_state) {
 495         case RXRPC_UNBOUND:
 496                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 497         case RXRPC_CLIENT_UNBOUND:
 498         case RXRPC_CLIENT_BOUND:
 499                 break;
 500         default:
 501                 ret = -EBUSY;
 502                 goto error;
 503         }
 504
 505         rx->connect_srx = *srx;
 506         set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
 507         ret = 0;
 508
 509 error:
 510         release_sock(&rx->sk);
 511         return ret;
 512 }
 513
 514 /*
 515  * send a message through an RxRPC socket
 516  * - in a client this does a number of things:
 517  *   - finds/sets up a connection for the security specified (if any)
 518  *   - initiates a call (ID in control data)
 519  *   - ends the request phase of a call (if MSG_MORE is not set)
 520  *   - sends a call data packet
 521  *   - may send an abort (abort code in control data)
 522  */
 523 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
 524 {
 525         struct rxrpc_local *local;
 526         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 527         int ret;
 528
 529         _enter(",{%d},,%zu", rx->sk.sk_state, len);
 530
 531         if (m->msg_flags & MSG_OOB)
 532                 return -EOPNOTSUPP;
 533
 534         if (m->msg_name) {
 535                 ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
 536                 if (ret < 0) {
 537                         _leave(" = %d [bad addr]", ret);
 538                         return ret;
 539                 }
 540         }
 541
 542         lock_sock(&rx->sk);
 543
 544         switch (rx->sk.sk_state) {
 545         case RXRPC_UNBOUND:
 546                 rx->srx.srx_family = AF_RXRPC;
 547                 rx->srx.srx_service = 0;
 548                 rx->srx.transport_type = SOCK_DGRAM;
 549                 rx->srx.transport.family = rx->family;
 550                 switch (rx->family) {
 551                 case AF_INET:
 552                         rx->srx.transport_len = sizeof(struct sockaddr_in);
 553                         break;
 554 #ifdef CONFIG_AF_RXRPC_IPV6
 555                 case AF_INET6:
 556                         rx->srx.transport_len = sizeof(struct sockaddr_in6);
 557                         break;
 558 #endif
 559                 default:
 560                         ret = -EAFNOSUPPORT;
 561                         goto error_unlock;
 562                 }
 563                 local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
 564                 if (IS_ERR(local)) {
 565                         ret = PTR_ERR(local);
 566                         goto error_unlock;
 567                 }
 568
 569                 rx->local = local;
 570                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 571                 /* Fall through */
 572
 573         case RXRPC_CLIENT_UNBOUND:
 574         case RXRPC_CLIENT_BOUND:
 575                 if (!m->msg_name &&
 576                     test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
 577                         m->msg_name = &rx->connect_srx;
 578                         m->msg_namelen = sizeof(rx->connect_srx);
 579                 }
 580                 /* Fall through */
 581         case RXRPC_SERVER_BOUND:
 582         case RXRPC_SERVER_LISTENING:
 583                 ret = rxrpc_do_sendmsg(rx, m, len);
 584                 /* The socket has been unlocked */
 585                 goto out;
 586         default:
 587                 ret = -EINVAL;
 588                 goto error_unlock;
 589         }
 590
 591 error_unlock:
 592         release_sock(&rx->sk);
 593 out:
 594         _leave(" = %d", ret);
 595         return ret;
 596 }
 597
 598 /*
 599  * set RxRPC socket options
 600  */
 601 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
 602                             char __user *optval, unsigned int optlen)
 603 {
 604         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 605         unsigned int min_sec_level;
 606         u16 service_upgrade[2];
 607         int ret;
 608
 609         _enter(",%d,%d,,%d", level, optname, optlen);
 610
 611         lock_sock(&rx->sk);
 612         ret = -EOPNOTSUPP;
 613
 614         if (level == SOL_RXRPC) {
 615                 switch (optname) {
 616                 case RXRPC_EXCLUSIVE_CONNECTION:
 617                         ret = -EINVAL;
 618                         if (optlen != 0)
 619                                 goto error;
 620                         ret = -EISCONN;
 621                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 622                                 goto error;
 623                         rx->exclusive = true;
 624                         goto success;
 625
 626                 case RXRPC_SECURITY_KEY:
 627                         ret = -EINVAL;
 628                         if (rx->key)
 629                                 goto error;
 630                         ret = -EISCONN;
 631                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 632                                 goto error;
 633                         ret = rxrpc_request_key(rx, optval, optlen);
 634                         goto error;
 635
 636                 case RXRPC_SECURITY_KEYRING:
 637                         ret = -EINVAL;
 638                         if (rx->key)
 639                                 goto error;
 640                         ret = -EISCONN;
 641                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 642                                 goto error;
 643                         ret = rxrpc_server_keyring(rx, optval, optlen);
 644                         goto error;
 645
 646                 case RXRPC_MIN_SECURITY_LEVEL:
 647                         ret = -EINVAL;
 648                         if (optlen != sizeof(unsigned int))
 649                                 goto error;
 650                         ret = -EISCONN;
 651                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 652                                 goto error;
 653                         ret = get_user(min_sec_level,
 654                                        (unsigned int __user *) optval);
 655                         if (ret < 0)
 656                                 goto error;
 657                         ret = -EINVAL;
 658                         if (min_sec_level > RXRPC_SECURITY_MAX)
 659                                 goto error;
 660                         rx->min_sec_level = min_sec_level;
 661                         goto success;
 662
 663                 case RXRPC_UPGRADEABLE_SERVICE:
 664                         ret = -EINVAL;
 665                         if (optlen != sizeof(service_upgrade) ||
 666                             rx->service_upgrade.from != 0)
 667                                 goto error;
 668                         ret = -EISCONN;
 669                         if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
 670                                 goto error;
 671                         ret = -EFAULT;
 672                         if (copy_from_user(service_upgrade, optval,
 673                                            sizeof(service_upgrade)) != 0)
 674                                 goto error;
 675                         ret = -EINVAL;
 676                         if ((service_upgrade[0] != rx->srx.srx_service ||
 677                              service_upgrade[1] != rx->second_service) &&
 678                             (service_upgrade[0] != rx->second_service ||
 679                              service_upgrade[1] != rx->srx.srx_service))
 680                                 goto error;
 681                         rx->service_upgrade.from = service_upgrade[0];
 682                         rx->service_upgrade.to = service_upgrade[1];
 683                         goto success;
 684
 685                 default:
 686                         break;
 687                 }
 688         }
 689
 690 success:
 691         ret = 0;
 692 error:
 693         release_sock(&rx->sk);
 694         return ret;
 695 }
 696
 697 /*
 698  * Get socket options.
 699  */
 700 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
 701                             char __user *optval, int __user *_optlen)
 702 {
 703         int optlen;
 704
 705         if (level != SOL_RXRPC)
 706                 return -EOPNOTSUPP;
 707
 708         if (get_user(optlen, _optlen))
 709                 return -EFAULT;
 710
 711         switch (optname) {
 712         case RXRPC_SUPPORTED_CMSG:
 713                 if (optlen < sizeof(int))
 714                         return -ETOOSMALL;
 715                 if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
 716                     put_user(sizeof(int), _optlen))
 717                         return -EFAULT;
 718                 return 0;
 719
 720         default:
 721                 return -EOPNOTSUPP;
 722         }
 723 }
 724
 725 /*
 726  * permit an RxRPC socket to be polled
 727  */
 728 static unsigned int rxrpc_poll(struct file *file, struct socket *sock,
 729                                poll_table *wait)
 730 {
 731         struct sock *sk = sock->sk;
 732         struct rxrpc_sock *rx = rxrpc_sk(sk);
 733         unsigned int mask;
 734
 735         sock_poll_wait(file, sk_sleep(sk), wait);
 736         mask = 0;
 737
 738         /* the socket is readable if there are any messages waiting on the Rx
 739          * queue */
 740         if (!list_empty(&rx->recvmsg_q))
 741                 mask |= POLLIN | POLLRDNORM;
 742
 743         /* the socket is writable if there is space to add new data to the
 744          * socket; there is no guarantee that any particular call in progress
 745          * on the socket may have space in the Tx ACK window */
 746         if (rxrpc_writable(sk))
 747                 mask |= POLLOUT | POLLWRNORM;
 748
 749         return mask;
 750 }
 751
 752 /*
 753  * create an RxRPC socket
 754  */
 755 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
 756                         int kern)
 757 {
 758         struct rxrpc_sock *rx;
 759         struct sock *sk;
 760
 761         _enter("%p,%d", sock, protocol);
 762
 763         /* we support transport protocol UDP/UDP6 only */
 764         if (protocol != PF_INET &&
 765             IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
 766                 return -EPROTONOSUPPORT;
 767
 768         if (sock->type != SOCK_DGRAM)
 769                 return -ESOCKTNOSUPPORT;
 770
 771         sock->ops = &rxrpc_rpc_ops;
 772         sock->state = SS_UNCONNECTED;
 773
 774         sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
 775         if (!sk)
 776                 return -ENOMEM;
 777
 778         sock_init_data(sock, sk);
 779         sock_set_flag(sk, SOCK_RCU_FREE);
 780         sk->sk_state            = RXRPC_UNBOUND;
 781         sk->sk_write_space      = rxrpc_write_space;
 782         sk->sk_max_ack_backlog  = 0;
 783         sk->sk_destruct         = rxrpc_sock_destructor;
 784
 785         rx = rxrpc_sk(sk);
 786         rx->family = protocol;
 787         rx->calls = RB_ROOT;
 788
 789         spin_lock_init(&rx->incoming_lock);
 790         INIT_LIST_HEAD(&rx->sock_calls);
 791         INIT_LIST_HEAD(&rx->to_be_accepted);
 792         INIT_LIST_HEAD(&rx->recvmsg_q);
 793         rwlock_init(&rx->recvmsg_lock);
 794         rwlock_init(&rx->call_lock);
 795         memset(&rx->srx, 0, sizeof(rx->srx));
 796
 797         _leave(" = 0 [%p]", rx);
 798         return 0;
 799 }
 800
 801 /*
 802  * Kill all the calls on a socket and shut it down.
 803  */
 804 static int rxrpc_shutdown(struct socket *sock, int flags)
 805 {
 806         struct sock *sk = sock->sk;
 807         struct rxrpc_sock *rx = rxrpc_sk(sk);
 808         int ret = 0;
 809
 810         _enter("%p,%d", sk, flags);
 811
 812         if (flags != SHUT_RDWR)
 813                 return -EOPNOTSUPP;
 814         if (sk->sk_state == RXRPC_CLOSE)
 815                 return -ESHUTDOWN;
 816
 817         lock_sock(sk);
 818
 819         spin_lock_bh(&sk->sk_receive_queue.lock);
 820         if (sk->sk_state < RXRPC_CLOSE) {
 821                 sk->sk_state = RXRPC_CLOSE;
 822                 sk->sk_shutdown = SHUTDOWN_MASK;
 823         } else {
 824                 ret = -ESHUTDOWN;
 825         }
 826         spin_unlock_bh(&sk->sk_receive_queue.lock);
 827
 828         rxrpc_discard_prealloc(rx);
 829
 830         release_sock(sk);
 831         return ret;
 832 }
 833
 834 /*
 835  * RxRPC socket destructor
 836  */
 837 static void rxrpc_sock_destructor(struct sock *sk)
 838 {
 839         _enter("%p", sk);
 840
 841         rxrpc_purge_queue(&sk->sk_receive_queue);
 842
 843         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
 844         WARN_ON(!sk_unhashed(sk));
 845         WARN_ON(sk->sk_socket);
 846
 847         if (!sock_flag(sk, SOCK_DEAD)) {
 848                 printk("Attempt to release alive rxrpc socket: %p\n", sk);
 849                 return;
 850         }
 851 }
 852
 853 /*
 854  * release an RxRPC socket
 855  */
 856 static int rxrpc_release_sock(struct sock *sk)
 857 {
 858         struct rxrpc_sock *rx = rxrpc_sk(sk);
 859
 860         _enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
 861
 862         /* declare the socket closed for business */
 863         sock_orphan(sk);
 864         sk->sk_shutdown = SHUTDOWN_MASK;
 865
 866         spin_lock_bh(&sk->sk_receive_queue.lock);
 867         sk->sk_state = RXRPC_CLOSE;
 868         spin_unlock_bh(&sk->sk_receive_queue.lock);
 869
 870         if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
 871                 write_lock(&rx->local->services_lock);
 872                 rcu_assign_pointer(rx->local->service, NULL);
 873                 write_unlock(&rx->local->services_lock);
 874         }
 875
 876         /* try to flush out this socket */
 877         rxrpc_discard_prealloc(rx);
 878         rxrpc_release_calls_on_socket(rx);
 879         flush_workqueue(rxrpc_workqueue);
 880         rxrpc_purge_queue(&sk->sk_receive_queue);
 881
 882         rxrpc_put_local(rx->local);
 883         rx->local = NULL;
 884         key_put(rx->key);
 885         rx->key = NULL;
 886         key_put(rx->securities);
 887         rx->securities = NULL;
 888         sock_put(sk);
 889
 890         _leave(" = 0");
 891         return 0;
 892 }
 893
 894 /*
 895  * release an RxRPC BSD socket on close() or equivalent
 896  */
 897 static int rxrpc_release(struct socket *sock)
 898 {
 899         struct sock *sk = sock->sk;
 900
 901         _enter("%p{%p}", sock, sk);
 902
 903         if (!sk)
 904                 return 0;
 905
 906         sock->sk = NULL;
 907
 908         return rxrpc_release_sock(sk);
 909 }
 910
 911 /*
 912  * RxRPC network protocol
 913  */
 914 static const struct proto_ops rxrpc_rpc_ops = {
 915         .family         = PF_RXRPC,
 916         .owner          = THIS_MODULE,
 917         .release        = rxrpc_release,
 918         .bind           = rxrpc_bind,
 919         .connect        = rxrpc_connect,
 920         .socketpair     = sock_no_socketpair,
 921         .accept         = sock_no_accept,
 922         .getname        = sock_no_getname,
 923         .poll           = rxrpc_poll,
 924         .ioctl          = sock_no_ioctl,
 925         .listen         = rxrpc_listen,
 926         .shutdown       = rxrpc_shutdown,
 927         .setsockopt     = rxrpc_setsockopt,
 928         .getsockopt     = rxrpc_getsockopt,
 929         .sendmsg        = rxrpc_sendmsg,
 930         .recvmsg        = rxrpc_recvmsg,
 931         .mmap           = sock_no_mmap,
 932         .sendpage       = sock_no_sendpage,
 933 };
 934
 935 static struct proto rxrpc_proto = {
 936         .name           = "RXRPC",
 937         .owner          = THIS_MODULE,
 938         .obj_size       = sizeof(struct rxrpc_sock),
 939         .max_header     = sizeof(struct rxrpc_wire_header),
 940 };
 941
 942 static const struct net_proto_family rxrpc_family_ops = {
 943         .family = PF_RXRPC,
 944         .create = rxrpc_create,
 945         .owner  = THIS_MODULE,
 946 };
 947
 948 /*
 949  * initialise and register the RxRPC protocol
 950  */
 951 static int __init af_rxrpc_init(void)
 952 {
 953         int ret = -1;
 954         unsigned int tmp;
 955
 956         BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
 957
 958         get_random_bytes(&tmp, sizeof(tmp));
 959         tmp &= 0x3fffffff;
 960         if (tmp == 0)
 961                 tmp = 1;
 962         idr_set_cursor(&rxrpc_client_conn_ids, tmp);
 963
 964         ret = -ENOMEM;
 965         rxrpc_call_jar = kmem_cache_create(
 966                 "rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
 967                 SLAB_HWCACHE_ALIGN, NULL);
 968         if (!rxrpc_call_jar) {
 969                 pr_notice("Failed to allocate call jar\n");
 970                 goto error_call_jar;
 971         }
 972
 973         rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
 974         if (!rxrpc_workqueue) {
 975                 pr_notice("Failed to allocate work queue\n");
 976                 goto error_work_queue;
 977         }
 978
 979         ret = rxrpc_init_security();
 980         if (ret < 0) {
 981                 pr_crit("Cannot initialise security\n");
 982                 goto error_security;
 983         }
 984
 985         ret = register_pernet_subsys(&rxrpc_net_ops);
 986         if (ret)
 987                 goto error_pernet;
 988
 989         ret = proto_register(&rxrpc_proto, 1);
 990         if (ret < 0) {
 991                 pr_crit("Cannot register protocol\n");
 992                 goto error_proto;
 993         }
 994
 995         ret = sock_register(&rxrpc_family_ops);
 996         if (ret < 0) {
 997                 pr_crit("Cannot register socket family\n");
 998                 goto error_sock;
 999         }
1000
1001         ret = register_key_type(&key_type_rxrpc);
1002         if (ret < 0) {
1003                 pr_crit("Cannot register client key type\n");
1004                 goto error_key_type;
1005         }
1006
1007         ret = register_key_type(&key_type_rxrpc_s);
1008         if (ret < 0) {
1009                 pr_crit("Cannot register server key type\n");
1010                 goto error_key_type_s;
1011         }
1012
1013         ret = rxrpc_sysctl_init();
1014         if (ret < 0) {
1015                 pr_crit("Cannot register sysctls\n");
1016                 goto error_sysctls;
1017         }
1018
1019         return 0;
1020
1021 error_sysctls:
1022         unregister_key_type(&key_type_rxrpc_s);
1023 error_key_type_s:
1024         unregister_key_type(&key_type_rxrpc);
1025 error_key_type:
1026         sock_unregister(PF_RXRPC);
1027 error_sock:
1028         proto_unregister(&rxrpc_proto);
1029 error_proto:
1030         unregister_pernet_subsys(&rxrpc_net_ops);
1031 error_pernet:
1032         rxrpc_exit_security();
1033 error_security:
1034         destroy_workqueue(rxrpc_workqueue);
1035 error_work_queue:
1036         kmem_cache_destroy(rxrpc_call_jar);
1037 error_call_jar:
1038         return ret;
1039 }
1040
1041 /*
1042  * unregister the RxRPC protocol
1043  */
1044 static void __exit af_rxrpc_exit(void)
1045 {
1046         _enter("");
1047         rxrpc_sysctl_exit();
1048         unregister_key_type(&key_type_rxrpc_s);
1049         unregister_key_type(&key_type_rxrpc);
1050         sock_unregister(PF_RXRPC);
1051         proto_unregister(&rxrpc_proto);
1052         unregister_pernet_subsys(&rxrpc_net_ops);
1053         ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
1054         ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1055
1056         /* Make sure the local and peer records pinned by any dying connections
1057          * are released.
1058          */
1059         rcu_barrier();
1060         rxrpc_destroy_client_conn_ids();
1061
1062         destroy_workqueue(rxrpc_workqueue);
1063         rxrpc_exit_security();
1064         kmem_cache_destroy(rxrpc_call_jar);
1065         _leave("");
1066 }
1067
1068 module_init(af_rxrpc_init);
1069 module_exit(af_rxrpc_exit);