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