net/rxrpc/af_rxrpc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* AF_RXRPC implementation
   3  *
   4  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   5  * Written by David Howells (dhowells@redhat.com)
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12 #include <linux/net.h>
  13 #include <linux/slab.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/random.h>
  16 #include <linux/poll.h>
  17 #include <linux/proc_fs.h>
  18 #include <linux/key-type.h>
  19 #include <net/net_namespace.h>
  20 #include <net/sock.h>
  21 #include <net/af_rxrpc.h>
  22 #define CREATE_TRACE_POINTS
  23 #include "ar-internal.h"
  24
  25 MODULE_DESCRIPTION("RxRPC network protocol");
  26 MODULE_AUTHOR("Red Hat, Inc.");
  27 MODULE_LICENSE("GPL");
  28 MODULE_ALIAS_NETPROTO(PF_RXRPC);
  29
  30 unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
  31 module_param_named(debug, rxrpc_debug, uint, 0644);
  32 MODULE_PARM_DESC(debug, "RxRPC debugging mask");
  33
  34 static struct proto rxrpc_proto;
  35 static const struct proto_ops rxrpc_rpc_ops;
  36
  37 /* current debugging ID */
  38 atomic_t rxrpc_debug_id;
  39 EXPORT_SYMBOL(rxrpc_debug_id);
  40
  41 /* count of skbs currently in use */
  42 atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_skbs;
  43
  44 struct workqueue_struct *rxrpc_workqueue;
  45
  46 static void rxrpc_sock_destructor(struct sock *);
  47
  48 /*
  49  * see if an RxRPC socket is currently writable
  50  */
  51 static inline int rxrpc_writable(struct sock *sk)
  52 {
  53         return refcount_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
  54 }
  55
  56 /*
  57  * wait for write bufferage to become available
  58  */
  59 static void rxrpc_write_space(struct sock *sk)
  60 {
  61         _enter("%p", sk);
  62         rcu_read_lock();
  63         if (rxrpc_writable(sk)) {
  64                 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
  65
  66                 if (skwq_has_sleeper(wq))
  67                         wake_up_interruptible(&wq->wait);
  68                 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
  69         }
  70         rcu_read_unlock();
  71 }
  72
  73 /*
  74  * validate an RxRPC address
  75  */
  76 static int rxrpc_validate_address(struct rxrpc_sock *rx,
  77                                   struct sockaddr_rxrpc *srx,
  78                                   int len)
  79 {
  80         unsigned int tail;
  81
  82         if (len < sizeof(struct sockaddr_rxrpc))
  83                 return -EINVAL;
  84
  85         if (srx->srx_family != AF_RXRPC)
  86                 return -EAFNOSUPPORT;
  87
  88         if (srx->transport_type != SOCK_DGRAM)
  89                 return -ESOCKTNOSUPPORT;
  90
  91         len -= offsetof(struct sockaddr_rxrpc, transport);
  92         if (srx->transport_len < sizeof(sa_family_t) ||
  93             srx->transport_len > len)
  94                 return -EINVAL;
  95
  96         if (srx->transport.family != rx->family &&
  97             srx->transport.family == AF_INET && rx->family != AF_INET6)
  98                 return -EAFNOSUPPORT;
  99
 100         switch (srx->transport.family) {
 101         case AF_INET:
 102                 if (srx->transport_len < sizeof(struct sockaddr_in))
 103                         return -EINVAL;
 104                 tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
 105                 break;
 106
 107 #ifdef CONFIG_AF_RXRPC_IPV6
 108         case AF_INET6:
 109                 if (srx->transport_len < sizeof(struct sockaddr_in6))
 110                         return -EINVAL;
 111                 tail = offsetof(struct sockaddr_rxrpc, transport) +
 112                         sizeof(struct sockaddr_in6);
 113                 break;
 114 #endif
 115
 116         default:
 117                 return -EAFNOSUPPORT;
 118         }
 119
 120         if (tail < len)
 121                 memset((void *)srx + tail, 0, len - tail);
 122         _debug("INET: %pISp", &srx->transport);
 123         return 0;
 124 }
 125
 126 /*
 127  * bind a local address to an RxRPC socket
 128  */
 129 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
 130 {
 131         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
 132         struct rxrpc_local *local;
 133         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 134         u16 service_id;
 135         int ret;
 136
 137         _enter("%p,%p,%d", rx, saddr, len);
 138
 139         ret = rxrpc_validate_address(rx, srx, len);
 140         if (ret < 0)
 141                 goto error;
 142         service_id = srx->srx_service;
 143
 144         lock_sock(&rx->sk);
 145
 146         switch (rx->sk.sk_state) {
 147         case RXRPC_UNBOUND:
 148                 rx->srx = *srx;
 149                 local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
 150                 if (IS_ERR(local)) {
 151                         ret = PTR_ERR(local);
 152                         goto error_unlock;
 153                 }
 154
 155                 if (service_id) {
 156                         write_lock(&local->services_lock);
 157                         if (rcu_access_pointer(local->service))
 158                                 goto service_in_use;
 159                         rx->local = local;
 160                         rcu_assign_pointer(local->service, rx);
 161                         write_unlock(&local->services_lock);
 162
 163                         rx->sk.sk_state = RXRPC_SERVER_BOUND;
 164                 } else {
 165                         rx->local = local;
 166                         rx->sk.sk_state = RXRPC_CLIENT_BOUND;
 167                 }
 168                 break;
 169
 170         case RXRPC_SERVER_BOUND:
 171                 ret = -EINVAL;
 172                 if (service_id == 0)
 173                         goto error_unlock;
 174                 ret = -EADDRINUSE;
 175                 if (service_id == rx->srx.srx_service)
 176                         goto error_unlock;
 177                 ret = -EINVAL;
 178                 srx->srx_service = rx->srx.srx_service;
 179                 if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0)
 180                         goto error_unlock;
 181                 rx->second_service = service_id;
 182                 rx->sk.sk_state = RXRPC_SERVER_BOUND2;
 183                 break;
 184
 185         default:
 186                 ret = -EINVAL;
 187                 goto error_unlock;
 188         }
 189
 190         release_sock(&rx->sk);
 191         _leave(" = 0");
 192         return 0;
 193
 194 service_in_use:
 195         write_unlock(&local->services_lock);
 196         rxrpc_unuse_local(local);
 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  * @intr: The call is interruptible
 271  * @debug_id: The debug ID for tracing to be assigned to the call
 272  *
 273  * Allow a kernel service to begin a call on the nominated socket.  This just
 274  * sets up all the internal tracking structures and allocates connection and
 275  * call IDs as appropriate.  The call to be used is returned.
 276  *
 277  * The default socket destination address and security may be overridden by
 278  * supplying @srx and @key.
 279  */
 280 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 281                                            struct sockaddr_rxrpc *srx,
 282                                            struct key *key,
 283                                            unsigned long user_call_ID,
 284                                            s64 tx_total_len,
 285                                            gfp_t gfp,
 286                                            rxrpc_notify_rx_t notify_rx,
 287                                            bool upgrade,
 288                                            enum rxrpc_interruptibility interruptibility,
 289                                            unsigned int debug_id)
 290 {
 291         struct rxrpc_conn_parameters cp;
 292         struct rxrpc_call_params p;
 293         struct rxrpc_call *call;
 294         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 295         int ret;
 296
 297         _enter(",,%x,%lx", key_serial(key), user_call_ID);
 298
 299         ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
 300         if (ret < 0)
 301                 return ERR_PTR(ret);
 302
 303         lock_sock(&rx->sk);
 304
 305         if (!key)
 306                 key = rx->key;
 307         if (key && !key->payload.data[0])
 308                 key = NULL; /* a no-security key */
 309
 310         memset(&p, 0, sizeof(p));
 311         p.user_call_ID = user_call_ID;
 312         p.tx_total_len = tx_total_len;
 313         p.interruptibility = interruptibility;
 314
 315         memset(&cp, 0, sizeof(cp));
 316         cp.local                = rx->local;
 317         cp.key                  = key;
 318         cp.security_level       = rx->min_sec_level;
 319         cp.exclusive            = false;
 320         cp.upgrade              = upgrade;
 321         cp.service_id           = srx->srx_service;
 322         call = rxrpc_new_client_call(rx, &cp, srx, &p, gfp, debug_id);
 323         /* The socket has been unlocked. */
 324         if (!IS_ERR(call)) {
 325                 call->notify_rx = notify_rx;
 326                 mutex_unlock(&call->user_mutex);
 327         }
 328
 329         rxrpc_put_peer(cp.peer);
 330         _leave(" = %p", call);
 331         return call;
 332 }
 333 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
 334
 335 /*
 336  * Dummy function used to stop the notifier talking to recvmsg().
 337  */
 338 static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall,
 339                                   unsigned long call_user_ID)
 340 {
 341 }
 342
 343 /**
 344  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
 345  * @sock: The socket the call is on
 346  * @call: The call to end
 347  *
 348  * Allow a kernel service to end a call it was using.  The call must be
 349  * complete before this is called (the call should be aborted if necessary).
 350  */
 351 void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
 352 {
 353         _enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
 354
 355         mutex_lock(&call->user_mutex);
 356         rxrpc_release_call(rxrpc_sk(sock->sk), call);
 357
 358         /* Make sure we're not going to call back into a kernel service */
 359         if (call->notify_rx) {
 360                 spin_lock_bh(&call->notify_lock);
 361                 call->notify_rx = rxrpc_dummy_notify_rx;
 362                 spin_unlock_bh(&call->notify_lock);
 363         }
 364
 365         mutex_unlock(&call->user_mutex);
 366         rxrpc_put_call(call, rxrpc_call_put_kernel);
 367 }
 368 EXPORT_SYMBOL(rxrpc_kernel_end_call);
 369
 370 /**
 371  * rxrpc_kernel_check_life - Check to see whether a call is still alive
 372  * @sock: The socket the call is on
 373  * @call: The call to check
 374  *
 375  * Allow a kernel service to find out whether a call is still alive -
 376  * ie. whether it has completed.
 377  */
 378 bool rxrpc_kernel_check_life(const struct socket *sock,
 379                              const struct rxrpc_call *call)
 380 {
 381         return call->state != RXRPC_CALL_COMPLETE;
 382 }
 383 EXPORT_SYMBOL(rxrpc_kernel_check_life);
 384
 385 /**
 386  * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
 387  * @sock: The socket the call is on
 388  * @call: The call to query
 389  *
 390  * Allow a kernel service to retrieve the epoch value from a service call to
 391  * see if the client at the other end rebooted.
 392  */
 393 u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
 394 {
 395         return call->conn->proto.epoch;
 396 }
 397 EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
 398
 399 /**
 400  * rxrpc_kernel_new_call_notification - Get notifications of new calls
 401  * @sock: The socket to intercept received messages on
 402  * @notify_new_call: Function to be called when new calls appear
 403  * @discard_new_call: Function to discard preallocated calls
 404  *
 405  * Allow a kernel service to be given notifications about new calls.
 406  */
 407 void rxrpc_kernel_new_call_notification(
 408         struct socket *sock,
 409         rxrpc_notify_new_call_t notify_new_call,
 410         rxrpc_discard_new_call_t discard_new_call)
 411 {
 412         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 413
 414         rx->notify_new_call = notify_new_call;
 415         rx->discard_new_call = discard_new_call;
 416 }
 417 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
 418
 419 /**
 420  * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
 421  * @sock: The socket the call is on
 422  * @call: The call to configure
 423  * @hard_timeout: The maximum lifespan of the call in jiffies
 424  *
 425  * Set the maximum lifespan of a call.  The call will end with ETIME or
 426  * ETIMEDOUT if it takes longer than this.
 427  */
 428 void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
 429                                unsigned long hard_timeout)
 430 {
 431         unsigned long now;
 432
 433         mutex_lock(&call->user_mutex);
 434
 435         now = jiffies;
 436         hard_timeout += now;
 437         WRITE_ONCE(call->expect_term_by, hard_timeout);
 438         rxrpc_reduce_call_timer(call, hard_timeout, now, rxrpc_timer_set_for_hard);
 439
 440         mutex_unlock(&call->user_mutex);
 441 }
 442 EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
 443
 444 /*
 445  * connect an RxRPC socket
 446  * - this just targets it at a specific destination; no actual connection
 447  *   negotiation takes place
 448  */
 449 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
 450                          int addr_len, int flags)
 451 {
 452         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
 453         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 454         int ret;
 455
 456         _enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
 457
 458         ret = rxrpc_validate_address(rx, srx, addr_len);
 459         if (ret < 0) {
 460                 _leave(" = %d [bad addr]", ret);
 461                 return ret;
 462         }
 463
 464         lock_sock(&rx->sk);
 465
 466         ret = -EISCONN;
 467         if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
 468                 goto error;
 469
 470         switch (rx->sk.sk_state) {
 471         case RXRPC_UNBOUND:
 472                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 473         case RXRPC_CLIENT_UNBOUND:
 474         case RXRPC_CLIENT_BOUND:
 475                 break;
 476         default:
 477                 ret = -EBUSY;
 478                 goto error;
 479         }
 480
 481         rx->connect_srx = *srx;
 482         set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
 483         ret = 0;
 484
 485 error:
 486         release_sock(&rx->sk);
 487         return ret;
 488 }
 489
 490 /*
 491  * send a message through an RxRPC socket
 492  * - in a client this does a number of things:
 493  *   - finds/sets up a connection for the security specified (if any)
 494  *   - initiates a call (ID in control data)
 495  *   - ends the request phase of a call (if MSG_MORE is not set)
 496  *   - sends a call data packet
 497  *   - may send an abort (abort code in control data)
 498  */
 499 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
 500 {
 501         struct rxrpc_local *local;
 502         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 503         int ret;
 504
 505         _enter(",{%d},,%zu", rx->sk.sk_state, len);
 506
 507         if (m->msg_flags & MSG_OOB)
 508                 return -EOPNOTSUPP;
 509
 510         if (m->msg_name) {
 511                 ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
 512                 if (ret < 0) {
 513                         _leave(" = %d [bad addr]", ret);
 514                         return ret;
 515                 }
 516         }
 517
 518         lock_sock(&rx->sk);
 519
 520         switch (rx->sk.sk_state) {
 521         case RXRPC_UNBOUND:
 522         case RXRPC_CLIENT_UNBOUND:
 523                 rx->srx.srx_family = AF_RXRPC;
 524                 rx->srx.srx_service = 0;
 525                 rx->srx.transport_type = SOCK_DGRAM;
 526                 rx->srx.transport.family = rx->family;
 527                 switch (rx->family) {
 528                 case AF_INET:
 529                         rx->srx.transport_len = sizeof(struct sockaddr_in);
 530                         break;
 531 #ifdef CONFIG_AF_RXRPC_IPV6
 532                 case AF_INET6:
 533                         rx->srx.transport_len = sizeof(struct sockaddr_in6);
 534                         break;
 535 #endif
 536                 default:
 537                         ret = -EAFNOSUPPORT;
 538                         goto error_unlock;
 539                 }
 540                 local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
 541                 if (IS_ERR(local)) {
 542                         ret = PTR_ERR(local);
 543                         goto error_unlock;
 544                 }
 545
 546                 rx->local = local;
 547                 rx->sk.sk_state = RXRPC_CLIENT_BOUND;
 548                 /* Fall through */
 549
 550         case RXRPC_CLIENT_BOUND:
 551                 if (!m->msg_name &&
 552                     test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
 553                         m->msg_name = &rx->connect_srx;
 554                         m->msg_namelen = sizeof(rx->connect_srx);
 555                 }
 556                 /* Fall through */
 557         case RXRPC_SERVER_BOUND:
 558         case RXRPC_SERVER_LISTENING:
 559                 ret = rxrpc_do_sendmsg(rx, m, len);
 560                 /* The socket has been unlocked */
 561                 goto out;
 562         default:
 563                 ret = -EINVAL;
 564                 goto error_unlock;
 565         }
 566
 567 error_unlock:
 568         release_sock(&rx->sk);
 569 out:
 570         _leave(" = %d", ret);
 571         return ret;
 572 }
 573
 574 int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val)
 575 {
 576         if (sk->sk_state != RXRPC_UNBOUND)
 577                 return -EISCONN;
 578         if (val > RXRPC_SECURITY_MAX)
 579                 return -EINVAL;
 580         lock_sock(sk);
 581         rxrpc_sk(sk)->min_sec_level = val;
 582         release_sock(sk);
 583         return 0;
 584 }
 585 EXPORT_SYMBOL(rxrpc_sock_set_min_security_level);
 586
 587 /*
 588  * set RxRPC socket options
 589  */
 590 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
 591                             char __user *optval, unsigned int optlen)
 592 {
 593         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 594         unsigned int min_sec_level;
 595         u16 service_upgrade[2];
 596         int ret;
 597
 598         _enter(",%d,%d,,%d", level, optname, optlen);
 599
 600         lock_sock(&rx->sk);
 601         ret = -EOPNOTSUPP;
 602
 603         if (level == SOL_RXRPC) {
 604                 switch (optname) {
 605                 case RXRPC_EXCLUSIVE_CONNECTION:
 606                         ret = -EINVAL;
 607                         if (optlen != 0)
 608                                 goto error;
 609                         ret = -EISCONN;
 610                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 611                                 goto error;
 612                         rx->exclusive = true;
 613                         goto success;
 614
 615                 case RXRPC_SECURITY_KEY:
 616                         ret = -EINVAL;
 617                         if (rx->key)
 618                                 goto error;
 619                         ret = -EISCONN;
 620                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 621                                 goto error;
 622                         ret = rxrpc_request_key(rx, optval, optlen);
 623                         goto error;
 624
 625                 case RXRPC_SECURITY_KEYRING:
 626                         ret = -EINVAL;
 627                         if (rx->key)
 628                                 goto error;
 629                         ret = -EISCONN;
 630                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 631                                 goto error;
 632                         ret = rxrpc_server_keyring(rx, optval, optlen);
 633                         goto error;
 634
 635                 case RXRPC_MIN_SECURITY_LEVEL:
 636                         ret = -EINVAL;
 637                         if (optlen != sizeof(unsigned int))
 638                                 goto error;
 639                         ret = -EISCONN;
 640                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 641                                 goto error;
 642                         ret = get_user(min_sec_level,
 643                                        (unsigned int __user *) optval);
 644                         if (ret < 0)
 645                                 goto error;
 646                         ret = -EINVAL;
 647                         if (min_sec_level > RXRPC_SECURITY_MAX)
 648                                 goto error;
 649                         rx->min_sec_level = min_sec_level;
 650                         goto success;
 651
 652                 case RXRPC_UPGRADEABLE_SERVICE:
 653                         ret = -EINVAL;
 654                         if (optlen != sizeof(service_upgrade) ||
 655                             rx->service_upgrade.from != 0)
 656                                 goto error;
 657                         ret = -EISCONN;
 658                         if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
 659                                 goto error;
 660                         ret = -EFAULT;
 661                         if (copy_from_user(service_upgrade, optval,
 662                                            sizeof(service_upgrade)) != 0)
 663                                 goto error;
 664                         ret = -EINVAL;
 665                         if ((service_upgrade[0] != rx->srx.srx_service ||
 666                              service_upgrade[1] != rx->second_service) &&
 667                             (service_upgrade[0] != rx->second_service ||
 668                              service_upgrade[1] != rx->srx.srx_service))
 669                                 goto error;
 670                         rx->service_upgrade.from = service_upgrade[0];
 671                         rx->service_upgrade.to = service_upgrade[1];
 672                         goto success;
 673
 674                 default:
 675                         break;
 676                 }
 677         }
 678
 679 success:
 680         ret = 0;
 681 error:
 682         release_sock(&rx->sk);
 683         return ret;
 684 }
 685
 686 /*
 687  * Get socket options.
 688  */
 689 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
 690                             char __user *optval, int __user *_optlen)
 691 {
 692         int optlen;
 693
 694         if (level != SOL_RXRPC)
 695                 return -EOPNOTSUPP;
 696
 697         if (get_user(optlen, _optlen))
 698                 return -EFAULT;
 699
 700         switch (optname) {
 701         case RXRPC_SUPPORTED_CMSG:
 702                 if (optlen < sizeof(int))
 703                         return -ETOOSMALL;
 704                 if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
 705                     put_user(sizeof(int), _optlen))
 706                         return -EFAULT;
 707                 return 0;
 708
 709         default:
 710                 return -EOPNOTSUPP;
 711         }
 712 }
 713
 714 /*
 715  * permit an RxRPC socket to be polled
 716  */
 717 static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
 718                                poll_table *wait)
 719 {
 720         struct sock *sk = sock->sk;
 721         struct rxrpc_sock *rx = rxrpc_sk(sk);
 722         __poll_t mask;
 723
 724         sock_poll_wait(file, sock, wait);
 725         mask = 0;
 726
 727         /* the socket is readable if there are any messages waiting on the Rx
 728          * queue */
 729         if (!list_empty(&rx->recvmsg_q))
 730                 mask |= EPOLLIN | EPOLLRDNORM;
 731
 732         /* the socket is writable if there is space to add new data to the
 733          * socket; there is no guarantee that any particular call in progress
 734          * on the socket may have space in the Tx ACK window */
 735         if (rxrpc_writable(sk))
 736                 mask |= EPOLLOUT | EPOLLWRNORM;
 737
 738         return mask;
 739 }
 740
 741 /*
 742  * create an RxRPC socket
 743  */
 744 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
 745                         int kern)
 746 {
 747         struct rxrpc_net *rxnet;
 748         struct rxrpc_sock *rx;
 749         struct sock *sk;
 750
 751         _enter("%p,%d", sock, protocol);
 752
 753         /* we support transport protocol UDP/UDP6 only */
 754         if (protocol != PF_INET &&
 755             IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
 756                 return -EPROTONOSUPPORT;
 757
 758         if (sock->type != SOCK_DGRAM)
 759                 return -ESOCKTNOSUPPORT;
 760
 761         sock->ops = &rxrpc_rpc_ops;
 762         sock->state = SS_UNCONNECTED;
 763
 764         sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
 765         if (!sk)
 766                 return -ENOMEM;
 767
 768         sock_init_data(sock, sk);
 769         sock_set_flag(sk, SOCK_RCU_FREE);
 770         sk->sk_state            = RXRPC_UNBOUND;
 771         sk->sk_write_space      = rxrpc_write_space;
 772         sk->sk_max_ack_backlog  = 0;
 773         sk->sk_destruct         = rxrpc_sock_destructor;
 774
 775         rx = rxrpc_sk(sk);
 776         rx->family = protocol;
 777         rx->calls = RB_ROOT;
 778
 779         spin_lock_init(&rx->incoming_lock);
 780         INIT_LIST_HEAD(&rx->sock_calls);
 781         INIT_LIST_HEAD(&rx->to_be_accepted);
 782         INIT_LIST_HEAD(&rx->recvmsg_q);
 783         rwlock_init(&rx->recvmsg_lock);
 784         rwlock_init(&rx->call_lock);
 785         memset(&rx->srx, 0, sizeof(rx->srx));
 786
 787         rxnet = rxrpc_net(sock_net(&rx->sk));
 788         timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
 789
 790         _leave(" = 0 [%p]", rx);
 791         return 0;
 792 }
 793
 794 /*
 795  * Kill all the calls on a socket and shut it down.
 796  */
 797 static int rxrpc_shutdown(struct socket *sock, int flags)
 798 {
 799         struct sock *sk = sock->sk;
 800         struct rxrpc_sock *rx = rxrpc_sk(sk);
 801         int ret = 0;
 802
 803         _enter("%p,%d", sk, flags);
 804
 805         if (flags != SHUT_RDWR)
 806                 return -EOPNOTSUPP;
 807         if (sk->sk_state == RXRPC_CLOSE)
 808                 return -ESHUTDOWN;
 809
 810         lock_sock(sk);
 811
 812         spin_lock_bh(&sk->sk_receive_queue.lock);
 813         if (sk->sk_state < RXRPC_CLOSE) {
 814                 sk->sk_state = RXRPC_CLOSE;
 815                 sk->sk_shutdown = SHUTDOWN_MASK;
 816         } else {
 817                 ret = -ESHUTDOWN;
 818         }
 819         spin_unlock_bh(&sk->sk_receive_queue.lock);
 820
 821         rxrpc_discard_prealloc(rx);
 822
 823         release_sock(sk);
 824         return ret;
 825 }
 826
 827 /*
 828  * RxRPC socket destructor
 829  */
 830 static void rxrpc_sock_destructor(struct sock *sk)
 831 {
 832         _enter("%p", sk);
 833
 834         rxrpc_purge_queue(&sk->sk_receive_queue);
 835
 836         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
 837         WARN_ON(!sk_unhashed(sk));
 838         WARN_ON(sk->sk_socket);
 839
 840         if (!sock_flag(sk, SOCK_DEAD)) {
 841                 printk("Attempt to release alive rxrpc socket: %p\n", sk);
 842                 return;
 843         }
 844 }
 845
 846 /*
 847  * release an RxRPC socket
 848  */
 849 static int rxrpc_release_sock(struct sock *sk)
 850 {
 851         struct rxrpc_sock *rx = rxrpc_sk(sk);
 852
 853         _enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
 854
 855         /* declare the socket closed for business */
 856         sock_orphan(sk);
 857         sk->sk_shutdown = SHUTDOWN_MASK;
 858
 859         /* We want to kill off all connections from a service socket
 860          * as fast as possible because we can't share these; client
 861          * sockets, on the other hand, can share an endpoint.
 862          */
 863         switch (sk->sk_state) {
 864         case RXRPC_SERVER_BOUND:
 865         case RXRPC_SERVER_BOUND2:
 866         case RXRPC_SERVER_LISTENING:
 867         case RXRPC_SERVER_LISTEN_DISABLED:
 868                 rx->local->service_closed = true;
 869                 break;
 870         }
 871
 872         spin_lock_bh(&sk->sk_receive_queue.lock);
 873         sk->sk_state = RXRPC_CLOSE;
 874         spin_unlock_bh(&sk->sk_receive_queue.lock);
 875
 876         if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
 877                 write_lock(&rx->local->services_lock);
 878                 rcu_assign_pointer(rx->local->service, NULL);
 879                 write_unlock(&rx->local->services_lock);
 880         }
 881
 882         /* try to flush out this socket */
 883         rxrpc_discard_prealloc(rx);
 884         rxrpc_release_calls_on_socket(rx);
 885         flush_workqueue(rxrpc_workqueue);
 886         rxrpc_purge_queue(&sk->sk_receive_queue);
 887
 888         rxrpc_unuse_local(rx->local);
 889         rxrpc_put_local(rx->local);
 890         rx->local = NULL;
 891         key_put(rx->key);
 892         rx->key = NULL;
 893         key_put(rx->securities);
 894         rx->securities = NULL;
 895         sock_put(sk);
 896
 897         _leave(" = 0");
 898         return 0;
 899 }
 900
 901 /*
 902  * release an RxRPC BSD socket on close() or equivalent
 903  */
 904 static int rxrpc_release(struct socket *sock)
 905 {
 906         struct sock *sk = sock->sk;
 907
 908         _enter("%p{%p}", sock, sk);
 909
 910         if (!sk)
 911                 return 0;
 912
 913         sock->sk = NULL;
 914
 915         return rxrpc_release_sock(sk);
 916 }
 917
 918 /*
 919  * RxRPC network protocol
 920  */
 921 static const struct proto_ops rxrpc_rpc_ops = {
 922         .family         = PF_RXRPC,
 923         .owner          = THIS_MODULE,
 924         .release        = rxrpc_release,
 925         .bind           = rxrpc_bind,
 926         .connect        = rxrpc_connect,
 927         .socketpair     = sock_no_socketpair,
 928         .accept         = sock_no_accept,
 929         .getname        = sock_no_getname,
 930         .poll           = rxrpc_poll,
 931         .ioctl          = sock_no_ioctl,
 932         .listen         = rxrpc_listen,
 933         .shutdown       = rxrpc_shutdown,
 934         .setsockopt     = rxrpc_setsockopt,
 935         .getsockopt     = rxrpc_getsockopt,
 936         .sendmsg        = rxrpc_sendmsg,
 937         .recvmsg        = rxrpc_recvmsg,
 938         .mmap           = sock_no_mmap,
 939         .sendpage       = sock_no_sendpage,
 940 };
 941
 942 static struct proto rxrpc_proto = {
 943         .name           = "RXRPC",
 944         .owner          = THIS_MODULE,
 945         .obj_size       = sizeof(struct rxrpc_sock),
 946         .max_header     = sizeof(struct rxrpc_wire_header),
 947 };
 948
 949 static const struct net_proto_family rxrpc_family_ops = {
 950         .family = PF_RXRPC,
 951         .create = rxrpc_create,
 952         .owner  = THIS_MODULE,
 953 };
 954
 955 /*
 956  * initialise and register the RxRPC protocol
 957  */
 958 static int __init af_rxrpc_init(void)
 959 {
 960         int ret = -1;
 961         unsigned int tmp;
 962
 963         BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof_field(struct sk_buff, cb));
 964
 965         get_random_bytes(&tmp, sizeof(tmp));
 966         tmp &= 0x3fffffff;
 967         if (tmp == 0)
 968                 tmp = 1;
 969         idr_set_cursor(&rxrpc_client_conn_ids, tmp);
 970
 971         ret = -ENOMEM;
 972         rxrpc_call_jar = kmem_cache_create(
 973                 "rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
 974                 SLAB_HWCACHE_ALIGN, NULL);
 975         if (!rxrpc_call_jar) {
 976                 pr_notice("Failed to allocate call jar\n");
 977                 goto error_call_jar;
 978         }
 979
 980         rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
 981         if (!rxrpc_workqueue) {
 982                 pr_notice("Failed to allocate work queue\n");
 983                 goto error_work_queue;
 984         }
 985
 986         ret = rxrpc_init_security();
 987         if (ret < 0) {
 988                 pr_crit("Cannot initialise security\n");
 989                 goto error_security;
 990         }
 991
 992         ret = register_pernet_subsys(&rxrpc_net_ops);
 993         if (ret)
 994                 goto error_pernet;
 995
 996         ret = proto_register(&rxrpc_proto, 1);
 997         if (ret < 0) {
 998                 pr_crit("Cannot register protocol\n");
 999                 goto error_proto;
1000         }
1001
1002         ret = sock_register(&rxrpc_family_ops);
1003         if (ret < 0) {
1004                 pr_crit("Cannot register socket family\n");
1005                 goto error_sock;
1006         }
1007
1008         ret = register_key_type(&key_type_rxrpc);
1009         if (ret < 0) {
1010                 pr_crit("Cannot register client key type\n");
1011                 goto error_key_type;
1012         }
1013
1014         ret = register_key_type(&key_type_rxrpc_s);
1015         if (ret < 0) {
1016                 pr_crit("Cannot register server key type\n");
1017                 goto error_key_type_s;
1018         }
1019
1020         ret = rxrpc_sysctl_init();
1021         if (ret < 0) {
1022                 pr_crit("Cannot register sysctls\n");
1023                 goto error_sysctls;
1024         }
1025
1026         return 0;
1027
1028 error_sysctls:
1029         unregister_key_type(&key_type_rxrpc_s);
1030 error_key_type_s:
1031         unregister_key_type(&key_type_rxrpc);
1032 error_key_type:
1033         sock_unregister(PF_RXRPC);
1034 error_sock:
1035         proto_unregister(&rxrpc_proto);
1036 error_proto:
1037         unregister_pernet_subsys(&rxrpc_net_ops);
1038 error_pernet:
1039         rxrpc_exit_security();
1040 error_security:
1041         destroy_workqueue(rxrpc_workqueue);
1042 error_work_queue:
1043         kmem_cache_destroy(rxrpc_call_jar);
1044 error_call_jar:
1045         return ret;
1046 }
1047
1048 /*
1049  * unregister the RxRPC protocol
1050  */
1051 static void __exit af_rxrpc_exit(void)
1052 {
1053         _enter("");
1054         rxrpc_sysctl_exit();
1055         unregister_key_type(&key_type_rxrpc_s);
1056         unregister_key_type(&key_type_rxrpc);
1057         sock_unregister(PF_RXRPC);
1058         proto_unregister(&rxrpc_proto);
1059         unregister_pernet_subsys(&rxrpc_net_ops);
1060         ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
1061         ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1062
1063         /* Make sure the local and peer records pinned by any dying connections
1064          * are released.
1065          */
1066         rcu_barrier();
1067         rxrpc_destroy_client_conn_ids();
1068
1069         destroy_workqueue(rxrpc_workqueue);
1070         rxrpc_exit_security();
1071         kmem_cache_destroy(rxrpc_call_jar);
1072         _leave("");
1073 }
1074
1075 module_init(af_rxrpc_init);
1076 module_exit(af_rxrpc_exit);