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         default:
 250                 ret = -EBUSY;
 251                 break;
 252         }
 253
 254         release_sock(&rx->sk);
 255         _leave(" = %d", ret);
 256         return ret;
 257 }
 258
 259 /**
 260  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
 261  * @sock: The socket on which to make the call
 262  * @srx: The address of the peer to contact
 263  * @key: The security context to use (defaults to socket setting)
 264  * @user_call_ID: The ID to use
 265  * @tx_total_len: Total length of data to transmit during the call (or -1)
 266  * @gfp: The allocation constraints
 267  * @notify_rx: Where to send notifications instead of socket queue
 268  *
 269  * Allow a kernel service to begin a call on the nominated socket.  This just
 270  * sets up all the internal tracking structures and allocates connection and
 271  * call IDs as appropriate.  The call to be used is returned.
 272  *
 273  * The default socket destination address and security may be overridden by
 274  * supplying @srx and @key.
 275  */
 276 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 277                                            struct sockaddr_rxrpc *srx,
 278                                            struct key *key,
 279                                            unsigned long user_call_ID,
 280                                            s64 tx_total_len,
 281                                            gfp_t gfp,
 282                                            rxrpc_notify_rx_t notify_rx)
 283 {
 284         struct rxrpc_conn_parameters cp;
 285         struct rxrpc_call *call;
 286         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 287         int ret;
 288
 289         _enter(",,%x,%lx", key_serial(key), user_call_ID);
 290
 291         ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
 292         if (ret < 0)
 293                 return ERR_PTR(ret);
 294
 295         lock_sock(&rx->sk);
 296
 297         if (!key)
 298                 key = rx->key;
 299         if (key && !key->payload.data[0])
 300                 key = NULL; /* a no-security key */
 301
 302         memset(&cp, 0, sizeof(cp));
 303         cp.local                = rx->local;
 304         cp.key                  = key;
 305         cp.security_level       = 0;
 306         cp.exclusive            = false;
 307         cp.service_id           = srx->srx_service;
 308         call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, tx_total_len,
 309                                      gfp);
 310         /* The socket has been unlocked. */
 311         if (!IS_ERR(call)) {
 312                 call->notify_rx = notify_rx;
 313                 mutex_unlock(&call->user_mutex);
 314         }
 315
 316         _leave(" = %p", call);
 317         return call;
 318 }
 319 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
 320
 321 /**
 322  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
 323  * @sock: The socket the call is on
 324  * @call: The call to end
 325  *
 326  * Allow a kernel service to end a call it was using.  The call must be
 327  * complete before this is called (the call should be aborted if necessary).
 328  */
 329 void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
 330 {
 331         _enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
 332
 333         mutex_lock(&call->user_mutex);
 334         rxrpc_release_call(rxrpc_sk(sock->sk), call);
 335         mutex_unlock(&call->user_mutex);
 336         rxrpc_put_call(call, rxrpc_call_put_kernel);
 337 }
 338 EXPORT_SYMBOL(rxrpc_kernel_end_call);
 339
 340 /**
 341  * rxrpc_kernel_check_call - Check a call's state
 342  * @sock: The socket the call is on
 343  * @call: The call to check
 344  * @_compl: Where to store the completion state
 345  * @_abort_code: Where to store any abort code
 346  *
 347  * Allow a kernel service to query the state of a call and find out the manner
 348  * of its termination if it has completed.  Returns -EINPROGRESS if the call is
 349  * still going, 0 if the call finished successfully, -ECONNABORTED if the call
 350  * was aborted and an appropriate error if the call failed in some other way.
 351  */
 352 int rxrpc_kernel_check_call(struct socket *sock, struct rxrpc_call *call,
 353                             enum rxrpc_call_completion *_compl, u32 *_abort_code)
 354 {
 355         if (call->state != RXRPC_CALL_COMPLETE)
 356                 return -EINPROGRESS;
 357         smp_rmb();
 358         *_compl = call->completion;
 359         *_abort_code = call->abort_code;
 360         return call->error;
 361 }
 362 EXPORT_SYMBOL(rxrpc_kernel_check_call);
 363
 364 /**
 365  * rxrpc_kernel_retry_call - Allow a kernel service to retry a call
 366  * @sock: The socket the call is on
 367  * @call: The call to retry
 368  * @srx: The address of the peer to contact
 369  * @key: The security context to use (defaults to socket setting)
 370  *
 371  * Allow a kernel service to try resending a client call that failed due to a
 372  * network error to a new address.  The Tx queue is maintained intact, thereby
 373  * relieving the need to re-encrypt any request data that has already been
 374  * buffered.
 375  */
 376 int rxrpc_kernel_retry_call(struct socket *sock, struct rxrpc_call *call,
 377                             struct sockaddr_rxrpc *srx, struct key *key)
 378 {
 379         struct rxrpc_conn_parameters cp;
 380         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 381         int ret;
 382
 383         _enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
 384
 385         if (!key)
 386                 key = rx->key;
 387         if (key && !key->payload.data[0])
 388                 key = NULL; /* a no-security key */
 389
 390         memset(&cp, 0, sizeof(cp));
 391         cp.local                = rx->local;
 392         cp.key                  = key;
 393         cp.security_level       = 0;
 394         cp.exclusive            = false;
 395         cp.service_id           = srx->srx_service;
 396
 397         mutex_lock(&call->user_mutex);
 398
 399         ret = rxrpc_prepare_call_for_retry(rx, call);
 400         if (ret == 0)
 401                 ret = rxrpc_retry_client_call(rx, call, &cp, srx, GFP_KERNEL);
 402
 403         mutex_unlock(&call->user_mutex);
 404         _leave(" = %d", ret);
 405         return ret;
 406 }
 407 EXPORT_SYMBOL(rxrpc_kernel_retry_call);
 408
 409 /**
 410  * rxrpc_kernel_new_call_notification - Get notifications of new calls
 411  * @sock: The socket to intercept received messages on
 412  * @notify_new_call: Function to be called when new calls appear
 413  * @discard_new_call: Function to discard preallocated calls
 414  *
 415  * Allow a kernel service to be given notifications about new calls.
 416  */
 417 void rxrpc_kernel_new_call_notification(
 418         struct socket *sock,
 419         rxrpc_notify_new_call_t notify_new_call,
 420         rxrpc_discard_new_call_t discard_new_call)
 421 {
 422         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 423
 424         rx->notify_new_call = notify_new_call;
 425         rx->discard_new_call = discard_new_call;
 426 }
 427 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
 428
 429 /*
 430  * connect an RxRPC socket
 431  * - this just targets it at a specific destination; no actual connection
 432  *   negotiation takes place
 433  */
 434 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
 435                          int addr_len, int flags)
 436 {
 437         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
 438         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 439         int ret;
 440
 441         _enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
 442
 443         ret = rxrpc_validate_address(rx, srx, addr_len);
 444         if (ret < 0) {
 445                 _leave(" = %d [bad addr]", ret);
 446                 return ret;
 447         }
 448
 449         lock_sock(&rx->sk);
 450
 451         ret = -EISCONN;
 452         if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
 453                 goto error;
 454
 455         switch (rx->sk.sk_state) {
 456         case RXRPC_UNBOUND:
 457                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 458         case RXRPC_CLIENT_UNBOUND:
 459         case RXRPC_CLIENT_BOUND:
 460                 break;
 461         default:
 462                 ret = -EBUSY;
 463                 goto error;
 464         }
 465
 466         rx->connect_srx = *srx;
 467         set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
 468         ret = 0;
 469
 470 error:
 471         release_sock(&rx->sk);
 472         return ret;
 473 }
 474
 475 /*
 476  * send a message through an RxRPC socket
 477  * - in a client this does a number of things:
 478  *   - finds/sets up a connection for the security specified (if any)
 479  *   - initiates a call (ID in control data)
 480  *   - ends the request phase of a call (if MSG_MORE is not set)
 481  *   - sends a call data packet
 482  *   - may send an abort (abort code in control data)
 483  */
 484 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
 485 {
 486         struct rxrpc_local *local;
 487         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 488         int ret;
 489
 490         _enter(",{%d},,%zu", rx->sk.sk_state, len);
 491
 492         if (m->msg_flags & MSG_OOB)
 493                 return -EOPNOTSUPP;
 494
 495         if (m->msg_name) {
 496                 ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
 497                 if (ret < 0) {
 498                         _leave(" = %d [bad addr]", ret);
 499                         return ret;
 500                 }
 501         }
 502
 503         lock_sock(&rx->sk);
 504
 505         switch (rx->sk.sk_state) {
 506         case RXRPC_UNBOUND:
 507                 rx->srx.srx_family = AF_RXRPC;
 508                 rx->srx.srx_service = 0;
 509                 rx->srx.transport_type = SOCK_DGRAM;
 510                 rx->srx.transport.family = rx->family;
 511                 switch (rx->family) {
 512                 case AF_INET:
 513                         rx->srx.transport_len = sizeof(struct sockaddr_in);
 514                         break;
 515 #ifdef CONFIG_AF_RXRPC_IPV6
 516                 case AF_INET6:
 517                         rx->srx.transport_len = sizeof(struct sockaddr_in6);
 518                         break;
 519 #endif
 520                 default:
 521                         ret = -EAFNOSUPPORT;
 522                         goto error_unlock;
 523                 }
 524                 local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
 525                 if (IS_ERR(local)) {
 526                         ret = PTR_ERR(local);
 527                         goto error_unlock;
 528                 }
 529
 530                 rx->local = local;
 531                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 532                 /* Fall through */
 533
 534         case RXRPC_CLIENT_UNBOUND:
 535         case RXRPC_CLIENT_BOUND:
 536                 if (!m->msg_name &&
 537                     test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
 538                         m->msg_name = &rx->connect_srx;
 539                         m->msg_namelen = sizeof(rx->connect_srx);
 540                 }
 541         case RXRPC_SERVER_BOUND:
 542         case RXRPC_SERVER_LISTENING:
 543                 ret = rxrpc_do_sendmsg(rx, m, len);
 544                 /* The socket has been unlocked */
 545                 goto out;
 546         default:
 547                 ret = -EINVAL;
 548                 goto error_unlock;
 549         }
 550
 551 error_unlock:
 552         release_sock(&rx->sk);
 553 out:
 554         _leave(" = %d", ret);
 555         return ret;
 556 }
 557
 558 /*
 559  * set RxRPC socket options
 560  */
 561 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
 562                             char __user *optval, unsigned int optlen)
 563 {
 564         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 565         unsigned int min_sec_level;
 566         u16 service_upgrade[2];
 567         int ret;
 568
 569         _enter(",%d,%d,,%d", level, optname, optlen);
 570
 571         lock_sock(&rx->sk);
 572         ret = -EOPNOTSUPP;
 573
 574         if (level == SOL_RXRPC) {
 575                 switch (optname) {
 576                 case RXRPC_EXCLUSIVE_CONNECTION:
 577                         ret = -EINVAL;
 578                         if (optlen != 0)
 579                                 goto error;
 580                         ret = -EISCONN;
 581                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 582                                 goto error;
 583                         rx->exclusive = true;
 584                         goto success;
 585
 586                 case RXRPC_SECURITY_KEY:
 587                         ret = -EINVAL;
 588                         if (rx->key)
 589                                 goto error;
 590                         ret = -EISCONN;
 591                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 592                                 goto error;
 593                         ret = rxrpc_request_key(rx, optval, optlen);
 594                         goto error;
 595
 596                 case RXRPC_SECURITY_KEYRING:
 597                         ret = -EINVAL;
 598                         if (rx->key)
 599                                 goto error;
 600                         ret = -EISCONN;
 601                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 602                                 goto error;
 603                         ret = rxrpc_server_keyring(rx, optval, optlen);
 604                         goto error;
 605
 606                 case RXRPC_MIN_SECURITY_LEVEL:
 607                         ret = -EINVAL;
 608                         if (optlen != sizeof(unsigned int))
 609                                 goto error;
 610                         ret = -EISCONN;
 611                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 612                                 goto error;
 613                         ret = get_user(min_sec_level,
 614                                        (unsigned int __user *) optval);
 615                         if (ret < 0)
 616                                 goto error;
 617                         ret = -EINVAL;
 618                         if (min_sec_level > RXRPC_SECURITY_MAX)
 619                                 goto error;
 620                         rx->min_sec_level = min_sec_level;
 621                         goto success;
 622
 623                 case RXRPC_UPGRADEABLE_SERVICE:
 624                         ret = -EINVAL;
 625                         if (optlen != sizeof(service_upgrade) ||
 626                             rx->service_upgrade.from != 0)
 627                                 goto error;
 628                         ret = -EISCONN;
 629                         if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
 630                                 goto error;
 631                         ret = -EFAULT;
 632                         if (copy_from_user(service_upgrade, optval,
 633                                            sizeof(service_upgrade)) != 0)
 634                                 goto error;
 635                         ret = -EINVAL;
 636                         if ((service_upgrade[0] != rx->srx.srx_service ||
 637                              service_upgrade[1] != rx->second_service) &&
 638                             (service_upgrade[0] != rx->second_service ||
 639                              service_upgrade[1] != rx->srx.srx_service))
 640                                 goto error;
 641                         rx->service_upgrade.from = service_upgrade[0];
 642                         rx->service_upgrade.to = service_upgrade[1];
 643                         goto success;
 644
 645                 default:
 646                         break;
 647                 }
 648         }
 649
 650 success:
 651         ret = 0;
 652 error:
 653         release_sock(&rx->sk);
 654         return ret;
 655 }
 656
 657 /*
 658  * Get socket options.
 659  */
 660 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
 661                             char __user *optval, int __user *_optlen)
 662 {
 663         int optlen;
 664
 665         if (level != SOL_RXRPC)
 666                 return -EOPNOTSUPP;
 667
 668         if (get_user(optlen, _optlen))
 669                 return -EFAULT;
 670
 671         switch (optname) {
 672         case RXRPC_SUPPORTED_CMSG:
 673                 if (optlen < sizeof(int))
 674                         return -ETOOSMALL;
 675                 if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
 676                     put_user(sizeof(int), _optlen))
 677                         return -EFAULT;
 678                 return 0;
 679
 680         default:
 681                 return -EOPNOTSUPP;
 682         }
 683 }
 684
 685 /*
 686  * permit an RxRPC socket to be polled
 687  */
 688 static unsigned int rxrpc_poll(struct file *file, struct socket *sock,
 689                                poll_table *wait)
 690 {
 691         struct sock *sk = sock->sk;
 692         struct rxrpc_sock *rx = rxrpc_sk(sk);
 693         unsigned int mask;
 694
 695         sock_poll_wait(file, sk_sleep(sk), wait);
 696         mask = 0;
 697
 698         /* the socket is readable if there are any messages waiting on the Rx
 699          * queue */
 700         if (!list_empty(&rx->recvmsg_q))
 701                 mask |= POLLIN | POLLRDNORM;
 702
 703         /* the socket is writable if there is space to add new data to the
 704          * socket; there is no guarantee that any particular call in progress
 705          * on the socket may have space in the Tx ACK window */
 706         if (rxrpc_writable(sk))
 707                 mask |= POLLOUT | POLLWRNORM;
 708
 709         return mask;
 710 }
 711
 712 /*
 713  * create an RxRPC socket
 714  */
 715 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
 716                         int kern)
 717 {
 718         struct rxrpc_sock *rx;
 719         struct sock *sk;
 720
 721         _enter("%p,%d", sock, protocol);
 722
 723         /* we support transport protocol UDP/UDP6 only */
 724         if (protocol != PF_INET &&
 725             IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
 726                 return -EPROTONOSUPPORT;
 727
 728         if (sock->type != SOCK_DGRAM)
 729                 return -ESOCKTNOSUPPORT;
 730
 731         sock->ops = &rxrpc_rpc_ops;
 732         sock->state = SS_UNCONNECTED;
 733
 734         sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
 735         if (!sk)
 736                 return -ENOMEM;
 737
 738         sock_init_data(sock, sk);
 739         sock_set_flag(sk, SOCK_RCU_FREE);
 740         sk->sk_state            = RXRPC_UNBOUND;
 741         sk->sk_write_space      = rxrpc_write_space;
 742         sk->sk_max_ack_backlog  = 0;
 743         sk->sk_destruct         = rxrpc_sock_destructor;
 744
 745         rx = rxrpc_sk(sk);
 746         rx->family = protocol;
 747         rx->calls = RB_ROOT;
 748
 749         spin_lock_init(&rx->incoming_lock);
 750         INIT_LIST_HEAD(&rx->sock_calls);
 751         INIT_LIST_HEAD(&rx->to_be_accepted);
 752         INIT_LIST_HEAD(&rx->recvmsg_q);
 753         rwlock_init(&rx->recvmsg_lock);
 754         rwlock_init(&rx->call_lock);
 755         memset(&rx->srx, 0, sizeof(rx->srx));
 756
 757         _leave(" = 0 [%p]", rx);
 758         return 0;
 759 }
 760
 761 /*
 762  * Kill all the calls on a socket and shut it down.
 763  */
 764 static int rxrpc_shutdown(struct socket *sock, int flags)
 765 {
 766         struct sock *sk = sock->sk;
 767         struct rxrpc_sock *rx = rxrpc_sk(sk);
 768         int ret = 0;
 769
 770         _enter("%p,%d", sk, flags);
 771
 772         if (flags != SHUT_RDWR)
 773                 return -EOPNOTSUPP;
 774         if (sk->sk_state == RXRPC_CLOSE)
 775                 return -ESHUTDOWN;
 776
 777         lock_sock(sk);
 778
 779         spin_lock_bh(&sk->sk_receive_queue.lock);
 780         if (sk->sk_state < RXRPC_CLOSE) {
 781                 sk->sk_state = RXRPC_CLOSE;
 782                 sk->sk_shutdown = SHUTDOWN_MASK;
 783         } else {
 784                 ret = -ESHUTDOWN;
 785         }
 786         spin_unlock_bh(&sk->sk_receive_queue.lock);
 787
 788         rxrpc_discard_prealloc(rx);
 789
 790         release_sock(sk);
 791         return ret;
 792 }
 793
 794 /*
 795  * RxRPC socket destructor
 796  */
 797 static void rxrpc_sock_destructor(struct sock *sk)
 798 {
 799         _enter("%p", sk);
 800
 801         rxrpc_purge_queue(&sk->sk_receive_queue);
 802
 803         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
 804         WARN_ON(!sk_unhashed(sk));
 805         WARN_ON(sk->sk_socket);
 806
 807         if (!sock_flag(sk, SOCK_DEAD)) {
 808                 printk("Attempt to release alive rxrpc socket: %p\n", sk);
 809                 return;
 810         }
 811 }
 812
 813 /*
 814  * release an RxRPC socket
 815  */
 816 static int rxrpc_release_sock(struct sock *sk)
 817 {
 818         struct rxrpc_sock *rx = rxrpc_sk(sk);
 819
 820         _enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
 821
 822         /* declare the socket closed for business */
 823         sock_orphan(sk);
 824         sk->sk_shutdown = SHUTDOWN_MASK;
 825
 826         spin_lock_bh(&sk->sk_receive_queue.lock);
 827         sk->sk_state = RXRPC_CLOSE;
 828         spin_unlock_bh(&sk->sk_receive_queue.lock);
 829
 830         if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
 831                 write_lock(&rx->local->services_lock);
 832                 rcu_assign_pointer(rx->local->service, NULL);
 833                 write_unlock(&rx->local->services_lock);
 834         }
 835
 836         /* try to flush out this socket */
 837         rxrpc_discard_prealloc(rx);
 838         rxrpc_release_calls_on_socket(rx);
 839         flush_workqueue(rxrpc_workqueue);
 840         rxrpc_purge_queue(&sk->sk_receive_queue);
 841
 842         rxrpc_put_local(rx->local);
 843         rx->local = NULL;
 844         key_put(rx->key);
 845         rx->key = NULL;
 846         key_put(rx->securities);
 847         rx->securities = NULL;
 848         sock_put(sk);
 849
 850         _leave(" = 0");
 851         return 0;
 852 }
 853
 854 /*
 855  * release an RxRPC BSD socket on close() or equivalent
 856  */
 857 static int rxrpc_release(struct socket *sock)
 858 {
 859         struct sock *sk = sock->sk;
 860
 861         _enter("%p{%p}", sock, sk);
 862
 863         if (!sk)
 864                 return 0;
 865
 866         sock->sk = NULL;
 867
 868         return rxrpc_release_sock(sk);
 869 }
 870
 871 /*
 872  * RxRPC network protocol
 873  */
 874 static const struct proto_ops rxrpc_rpc_ops = {
 875         .family         = PF_RXRPC,
 876         .owner          = THIS_MODULE,
 877         .release        = rxrpc_release,
 878         .bind           = rxrpc_bind,
 879         .connect        = rxrpc_connect,
 880         .socketpair     = sock_no_socketpair,
 881         .accept         = sock_no_accept,
 882         .getname        = sock_no_getname,
 883         .poll           = rxrpc_poll,
 884         .ioctl          = sock_no_ioctl,
 885         .listen         = rxrpc_listen,
 886         .shutdown       = rxrpc_shutdown,
 887         .setsockopt     = rxrpc_setsockopt,
 888         .getsockopt     = rxrpc_getsockopt,
 889         .sendmsg        = rxrpc_sendmsg,
 890         .recvmsg        = rxrpc_recvmsg,
 891         .mmap           = sock_no_mmap,
 892         .sendpage       = sock_no_sendpage,
 893 };
 894
 895 static struct proto rxrpc_proto = {
 896         .name           = "RXRPC",
 897         .owner          = THIS_MODULE,
 898         .obj_size       = sizeof(struct rxrpc_sock),
 899         .max_header     = sizeof(struct rxrpc_wire_header),
 900 };
 901
 902 static const struct net_proto_family rxrpc_family_ops = {
 903         .family = PF_RXRPC,
 904         .create = rxrpc_create,
 905         .owner  = THIS_MODULE,
 906 };
 907
 908 /*
 909  * initialise and register the RxRPC protocol
 910  */
 911 static int __init af_rxrpc_init(void)
 912 {
 913         int ret = -1;
 914         unsigned int tmp;
 915
 916         BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
 917
 918         get_random_bytes(&tmp, sizeof(tmp));
 919         tmp &= 0x3fffffff;
 920         if (tmp == 0)
 921                 tmp = 1;
 922         idr_set_cursor(&rxrpc_client_conn_ids, tmp);
 923
 924         ret = -ENOMEM;
 925         rxrpc_call_jar = kmem_cache_create(
 926                 "rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
 927                 SLAB_HWCACHE_ALIGN, NULL);
 928         if (!rxrpc_call_jar) {
 929                 pr_notice("Failed to allocate call jar\n");
 930                 goto error_call_jar;
 931         }
 932
 933         rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
 934         if (!rxrpc_workqueue) {
 935                 pr_notice("Failed to allocate work queue\n");
 936                 goto error_work_queue;
 937         }
 938
 939         ret = rxrpc_init_security();
 940         if (ret < 0) {
 941                 pr_crit("Cannot initialise security\n");
 942                 goto error_security;
 943         }
 944
 945         ret = register_pernet_subsys(&rxrpc_net_ops);
 946         if (ret)
 947                 goto error_pernet;
 948
 949         ret = proto_register(&rxrpc_proto, 1);
 950         if (ret < 0) {
 951                 pr_crit("Cannot register protocol\n");
 952                 goto error_proto;
 953         }
 954
 955         ret = sock_register(&rxrpc_family_ops);
 956         if (ret < 0) {
 957                 pr_crit("Cannot register socket family\n");
 958                 goto error_sock;
 959         }
 960
 961         ret = register_key_type(&key_type_rxrpc);
 962         if (ret < 0) {
 963                 pr_crit("Cannot register client key type\n");
 964                 goto error_key_type;
 965         }
 966
 967         ret = register_key_type(&key_type_rxrpc_s);
 968         if (ret < 0) {
 969                 pr_crit("Cannot register server key type\n");
 970                 goto error_key_type_s;
 971         }
 972
 973         ret = rxrpc_sysctl_init();
 974         if (ret < 0) {
 975                 pr_crit("Cannot register sysctls\n");
 976                 goto error_sysctls;
 977         }
 978
 979         return 0;
 980
 981 error_sysctls:
 982         unregister_key_type(&key_type_rxrpc_s);
 983 error_key_type_s:
 984         unregister_key_type(&key_type_rxrpc);
 985 error_key_type:
 986         sock_unregister(PF_RXRPC);
 987 error_sock:
 988         proto_unregister(&rxrpc_proto);
 989 error_proto:
 990         unregister_pernet_subsys(&rxrpc_net_ops);
 991 error_pernet:
 992         rxrpc_exit_security();
 993 error_security:
 994         destroy_workqueue(rxrpc_workqueue);
 995 error_work_queue:
 996         kmem_cache_destroy(rxrpc_call_jar);
 997 error_call_jar:
 998         return ret;
 999 }
1000
1001 /*
1002  * unregister the RxRPC protocol
1003  */
1004 static void __exit af_rxrpc_exit(void)
1005 {
1006         _enter("");
1007         rxrpc_sysctl_exit();
1008         unregister_key_type(&key_type_rxrpc_s);
1009         unregister_key_type(&key_type_rxrpc);
1010         sock_unregister(PF_RXRPC);
1011         proto_unregister(&rxrpc_proto);
1012         unregister_pernet_subsys(&rxrpc_net_ops);
1013         ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
1014         ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1015
1016         /* Make sure the local and peer records pinned by any dying connections
1017          * are released.
1018          */
1019         rcu_barrier();
1020         rxrpc_destroy_client_conn_ids();
1021
1022         destroy_workqueue(rxrpc_workqueue);
1023         rxrpc_exit_security();
1024         kmem_cache_destroy(rxrpc_call_jar);
1025         _leave("");
1026 }
1027
1028 module_init(af_rxrpc_init);
1029 module_exit(af_rxrpc_exit);