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         ret = -EADDRINUSE;
 198 error_unlock:
 199         release_sock(&rx->sk);
 200 error:
 201         _leave(" = %d", ret);
 202         return ret;
 203 }
 204
 205 /*
 206  * set the number of pending calls permitted on a listening socket
 207  */
 208 static int rxrpc_listen(struct socket *sock, int backlog)
 209 {
 210         struct sock *sk = sock->sk;
 211         struct rxrpc_sock *rx = rxrpc_sk(sk);
 212         unsigned int max, old;
 213         int ret;
 214
 215         _enter("%p,%d", rx, backlog);
 216
 217         lock_sock(&rx->sk);
 218
 219         switch (rx->sk.sk_state) {
 220         case RXRPC_UNBOUND:
 221                 ret = -EADDRNOTAVAIL;
 222                 break;
 223         case RXRPC_SERVER_BOUND:
 224         case RXRPC_SERVER_BOUND2:
 225                 ASSERT(rx->local != NULL);
 226                 max = READ_ONCE(rxrpc_max_backlog);
 227                 ret = -EINVAL;
 228                 if (backlog == INT_MAX)
 229                         backlog = max;
 230                 else if (backlog < 0 || backlog > max)
 231                         break;
 232                 old = sk->sk_max_ack_backlog;
 233                 sk->sk_max_ack_backlog = backlog;
 234                 ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
 235                 if (ret == 0)
 236                         rx->sk.sk_state = RXRPC_SERVER_LISTENING;
 237                 else
 238                         sk->sk_max_ack_backlog = old;
 239                 break;
 240         case RXRPC_SERVER_LISTENING:
 241                 if (backlog == 0) {
 242                         rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED;
 243                         sk->sk_max_ack_backlog = 0;
 244                         rxrpc_discard_prealloc(rx);
 245                         ret = 0;
 246                         break;
 247                 }
 248                 /* Fall through */
 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  * @upgrade: Request service upgrade for call
 269  * @intr: The call is interruptible
 270  * @debug_id: The debug ID for tracing to be assigned to the call
 271  *
 272  * Allow a kernel service to begin a call on the nominated socket.  This just
 273  * sets up all the internal tracking structures and allocates connection and
 274  * call IDs as appropriate.  The call to be used is returned.
 275  *
 276  * The default socket destination address and security may be overridden by
 277  * supplying @srx and @key.
 278  */
 279 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 280                                            struct sockaddr_rxrpc *srx,
 281                                            struct key *key,
 282                                            unsigned long user_call_ID,
 283                                            s64 tx_total_len,
 284                                            gfp_t gfp,
 285                                            rxrpc_notify_rx_t notify_rx,
 286                                            bool upgrade,
 287                                            bool intr,
 288                                            unsigned int debug_id)
 289 {
 290         struct rxrpc_conn_parameters cp;
 291         struct rxrpc_call_params p;
 292         struct rxrpc_call *call;
 293         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 294         int ret;
 295
 296         _enter(",,%x,%lx", key_serial(key), user_call_ID);
 297
 298         ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
 299         if (ret < 0)
 300                 return ERR_PTR(ret);
 301
 302         lock_sock(&rx->sk);
 303
 304         if (!key)
 305                 key = rx->key;
 306         if (key && !key->payload.data[0])
 307                 key = NULL; /* a no-security key */
 308
 309         memset(&p, 0, sizeof(p));
 310         p.user_call_ID = user_call_ID;
 311         p.tx_total_len = tx_total_len;
 312         p.intr = intr;
 313
 314         memset(&cp, 0, sizeof(cp));
 315         cp.local                = rx->local;
 316         cp.key                  = key;
 317         cp.security_level       = rx->min_sec_level;
 318         cp.exclusive            = false;
 319         cp.upgrade              = upgrade;
 320         cp.service_id           = srx->srx_service;
 321         call = rxrpc_new_client_call(rx, &cp, srx, &p, gfp, debug_id);
 322         /* The socket has been unlocked. */
 323         if (!IS_ERR(call)) {
 324                 call->notify_rx = notify_rx;
 325                 mutex_unlock(&call->user_mutex);
 326         }
 327
 328         rxrpc_put_peer(cp.peer);
 329         _leave(" = %p", call);
 330         return call;
 331 }
 332 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
 333
 334 /*
 335  * Dummy function used to stop the notifier talking to recvmsg().
 336  */
 337 static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall,
 338                                   unsigned long call_user_ID)
 339 {
 340 }
 341
 342 /**
 343  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
 344  * @sock: The socket the call is on
 345  * @call: The call to end
 346  *
 347  * Allow a kernel service to end a call it was using.  The call must be
 348  * complete before this is called (the call should be aborted if necessary).
 349  */
 350 void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
 351 {
 352         _enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
 353
 354         mutex_lock(&call->user_mutex);
 355         rxrpc_release_call(rxrpc_sk(sock->sk), call);
 356
 357         /* Make sure we're not going to call back into a kernel service */
 358         if (call->notify_rx) {
 359                 spin_lock_bh(&call->notify_lock);
 360                 call->notify_rx = rxrpc_dummy_notify_rx;
 361                 spin_unlock_bh(&call->notify_lock);
 362         }
 363
 364         mutex_unlock(&call->user_mutex);
 365         rxrpc_put_call(call, rxrpc_call_put_kernel);
 366 }
 367 EXPORT_SYMBOL(rxrpc_kernel_end_call);
 368
 369 /**
 370  * rxrpc_kernel_check_life - Check to see whether a call is still alive
 371  * @sock: The socket the call is on
 372  * @call: The call to check
 373  * @_life: Where to store the life value
 374  *
 375  * Allow a kernel service to find out whether a call is still alive - ie. we're
 376  * getting ACKs from the server.  Passes back in *_life a number representing
 377  * the life state which can be compared to that returned by a previous call and
 378  * return true if the call is still alive.
 379  *
 380  * If the life state stalls, rxrpc_kernel_probe_life() should be called and
 381  * then 2RTT waited.
 382  */
 383 bool rxrpc_kernel_check_life(const struct socket *sock,
 384                              const struct rxrpc_call *call,
 385                              u32 *_life)
 386 {
 387         *_life = call->acks_latest;
 388         return call->state != RXRPC_CALL_COMPLETE;
 389 }
 390 EXPORT_SYMBOL(rxrpc_kernel_check_life);
 391
 392 /**
 393  * rxrpc_kernel_probe_life - Poke the peer to see if it's still alive
 394  * @sock: The socket the call is on
 395  * @call: The call to check
 396  *
 397  * In conjunction with rxrpc_kernel_check_life(), allow a kernel service to
 398  * find out whether a call is still alive by pinging it.  This should cause the
 399  * life state to be bumped in about 2*RTT.
 400  *
 401  * The must be called in TASK_RUNNING state on pain of might_sleep() objecting.
 402  */
 403 void rxrpc_kernel_probe_life(struct socket *sock, struct rxrpc_call *call)
 404 {
 405         rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, true, false,
 406                           rxrpc_propose_ack_ping_for_check_life);
 407         rxrpc_send_ack_packet(call, true, NULL);
 408 }
 409 EXPORT_SYMBOL(rxrpc_kernel_probe_life);
 410
 411 /**
 412  * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
 413  * @sock: The socket the call is on
 414  * @call: The call to query
 415  *
 416  * Allow a kernel service to retrieve the epoch value from a service call to
 417  * see if the client at the other end rebooted.
 418  */
 419 u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
 420 {
 421         return call->conn->proto.epoch;
 422 }
 423 EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
 424
 425 /**
 426  * rxrpc_kernel_new_call_notification - Get notifications of new calls
 427  * @sock: The socket to intercept received messages on
 428  * @notify_new_call: Function to be called when new calls appear
 429  * @discard_new_call: Function to discard preallocated calls
 430  *
 431  * Allow a kernel service to be given notifications about new calls.
 432  */
 433 void rxrpc_kernel_new_call_notification(
 434         struct socket *sock,
 435         rxrpc_notify_new_call_t notify_new_call,
 436         rxrpc_discard_new_call_t discard_new_call)
 437 {
 438         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 439
 440         rx->notify_new_call = notify_new_call;
 441         rx->discard_new_call = discard_new_call;
 442 }
 443 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
 444
 445 /**
 446  * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
 447  * @sock: The socket the call is on
 448  * @call: The call to configure
 449  * @hard_timeout: The maximum lifespan of the call in jiffies
 450  *
 451  * Set the maximum lifespan of a call.  The call will end with ETIME or
 452  * ETIMEDOUT if it takes longer than this.
 453  */
 454 void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
 455                                unsigned long hard_timeout)
 456 {
 457         unsigned long now;
 458
 459         mutex_lock(&call->user_mutex);
 460
 461         now = jiffies;
 462         hard_timeout += now;
 463         WRITE_ONCE(call->expect_term_by, hard_timeout);
 464         rxrpc_reduce_call_timer(call, hard_timeout, now, rxrpc_timer_set_for_hard);
 465
 466         mutex_unlock(&call->user_mutex);
 467 }
 468 EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
 469
 470 /*
 471  * connect an RxRPC socket
 472  * - this just targets it at a specific destination; no actual connection
 473  *   negotiation takes place
 474  */
 475 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
 476                          int addr_len, int flags)
 477 {
 478         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
 479         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 480         int ret;
 481
 482         _enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
 483
 484         ret = rxrpc_validate_address(rx, srx, addr_len);
 485         if (ret < 0) {
 486                 _leave(" = %d [bad addr]", ret);
 487                 return ret;
 488         }
 489
 490         lock_sock(&rx->sk);
 491
 492         ret = -EISCONN;
 493         if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
 494                 goto error;
 495
 496         switch (rx->sk.sk_state) {
 497         case RXRPC_UNBOUND:
 498                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 499         case RXRPC_CLIENT_UNBOUND:
 500         case RXRPC_CLIENT_BOUND:
 501                 break;
 502         default:
 503                 ret = -EBUSY;
 504                 goto error;
 505         }
 506
 507         rx->connect_srx = *srx;
 508         set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
 509         ret = 0;
 510
 511 error:
 512         release_sock(&rx->sk);
 513         return ret;
 514 }
 515
 516 /*
 517  * send a message through an RxRPC socket
 518  * - in a client this does a number of things:
 519  *   - finds/sets up a connection for the security specified (if any)
 520  *   - initiates a call (ID in control data)
 521  *   - ends the request phase of a call (if MSG_MORE is not set)
 522  *   - sends a call data packet
 523  *   - may send an abort (abort code in control data)
 524  */
 525 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
 526 {
 527         struct rxrpc_local *local;
 528         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 529         int ret;
 530
 531         _enter(",{%d},,%zu", rx->sk.sk_state, len);
 532
 533         if (m->msg_flags & MSG_OOB)
 534                 return -EOPNOTSUPP;
 535
 536         if (m->msg_name) {
 537                 ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
 538                 if (ret < 0) {
 539                         _leave(" = %d [bad addr]", ret);
 540                         return ret;
 541                 }
 542         }
 543
 544         lock_sock(&rx->sk);
 545
 546         switch (rx->sk.sk_state) {
 547         case RXRPC_UNBOUND:
 548         case RXRPC_CLIENT_UNBOUND:
 549                 rx->srx.srx_family = AF_RXRPC;
 550                 rx->srx.srx_service = 0;
 551                 rx->srx.transport_type = SOCK_DGRAM;
 552                 rx->srx.transport.family = rx->family;
 553                 switch (rx->family) {
 554                 case AF_INET:
 555                         rx->srx.transport_len = sizeof(struct sockaddr_in);
 556                         break;
 557 #ifdef CONFIG_AF_RXRPC_IPV6
 558                 case AF_INET6:
 559                         rx->srx.transport_len = sizeof(struct sockaddr_in6);
 560                         break;
 561 #endif
 562                 default:
 563                         ret = -EAFNOSUPPORT;
 564                         goto error_unlock;
 565                 }
 566                 local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
 567                 if (IS_ERR(local)) {
 568                         ret = PTR_ERR(local);
 569                         goto error_unlock;
 570                 }
 571
 572                 rx->local = local;
 573                 rx->sk.sk_state = RXRPC_CLIENT_BOUND;
 574                 /* Fall through */
 575
 576         case RXRPC_CLIENT_BOUND:
 577                 if (!m->msg_name &&
 578                     test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
 579                         m->msg_name = &rx->connect_srx;
 580                         m->msg_namelen = sizeof(rx->connect_srx);
 581                 }
 582                 /* Fall through */
 583         case RXRPC_SERVER_BOUND:
 584         case RXRPC_SERVER_LISTENING:
 585                 ret = rxrpc_do_sendmsg(rx, m, len);
 586                 /* The socket has been unlocked */
 587                 goto out;
 588         default:
 589                 ret = -EINVAL;
 590                 goto error_unlock;
 591         }
 592
 593 error_unlock:
 594         release_sock(&rx->sk);
 595 out:
 596         _leave(" = %d", ret);
 597         return ret;
 598 }
 599
 600 /*
 601  * set RxRPC socket options
 602  */
 603 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
 604                             char __user *optval, unsigned int optlen)
 605 {
 606         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 607         unsigned int min_sec_level;
 608         u16 service_upgrade[2];
 609         int ret;
 610
 611         _enter(",%d,%d,,%d", level, optname, optlen);
 612
 613         lock_sock(&rx->sk);
 614         ret = -EOPNOTSUPP;
 615
 616         if (level == SOL_RXRPC) {
 617                 switch (optname) {
 618                 case RXRPC_EXCLUSIVE_CONNECTION:
 619                         ret = -EINVAL;
 620                         if (optlen != 0)
 621                                 goto error;
 622                         ret = -EISCONN;
 623                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 624                                 goto error;
 625                         rx->exclusive = true;
 626                         goto success;
 627
 628                 case RXRPC_SECURITY_KEY:
 629                         ret = -EINVAL;
 630                         if (rx->key)
 631                                 goto error;
 632                         ret = -EISCONN;
 633                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 634                                 goto error;
 635                         ret = rxrpc_request_key(rx, optval, optlen);
 636                         goto error;
 637
 638                 case RXRPC_SECURITY_KEYRING:
 639                         ret = -EINVAL;
 640                         if (rx->key)
 641                                 goto error;
 642                         ret = -EISCONN;
 643                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 644                                 goto error;
 645                         ret = rxrpc_server_keyring(rx, optval, optlen);
 646                         goto error;
 647
 648                 case RXRPC_MIN_SECURITY_LEVEL:
 649                         ret = -EINVAL;
 650                         if (optlen != sizeof(unsigned int))
 651                                 goto error;
 652                         ret = -EISCONN;
 653                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 654                                 goto error;
 655                         ret = get_user(min_sec_level,
 656                                        (unsigned int __user *) optval);
 657                         if (ret < 0)
 658                                 goto error;
 659                         ret = -EINVAL;
 660                         if (min_sec_level > RXRPC_SECURITY_MAX)
 661                                 goto error;
 662                         rx->min_sec_level = min_sec_level;
 663                         goto success;
 664
 665                 case RXRPC_UPGRADEABLE_SERVICE:
 666                         ret = -EINVAL;
 667                         if (optlen != sizeof(service_upgrade) ||
 668                             rx->service_upgrade.from != 0)
 669                                 goto error;
 670                         ret = -EISCONN;
 671                         if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
 672                                 goto error;
 673                         ret = -EFAULT;
 674                         if (copy_from_user(service_upgrade, optval,
 675                                            sizeof(service_upgrade)) != 0)
 676                                 goto error;
 677                         ret = -EINVAL;
 678                         if ((service_upgrade[0] != rx->srx.srx_service ||
 679                              service_upgrade[1] != rx->second_service) &&
 680                             (service_upgrade[0] != rx->second_service ||
 681                              service_upgrade[1] != rx->srx.srx_service))
 682                                 goto error;
 683                         rx->service_upgrade.from = service_upgrade[0];
 684                         rx->service_upgrade.to = service_upgrade[1];
 685                         goto success;
 686
 687                 default:
 688                         break;
 689                 }
 690         }
 691
 692 success:
 693         ret = 0;
 694 error:
 695         release_sock(&rx->sk);
 696         return ret;
 697 }
 698
 699 /*
 700  * Get socket options.
 701  */
 702 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
 703                             char __user *optval, int __user *_optlen)
 704 {
 705         int optlen;
 706
 707         if (level != SOL_RXRPC)
 708                 return -EOPNOTSUPP;
 709
 710         if (get_user(optlen, _optlen))
 711                 return -EFAULT;
 712
 713         switch (optname) {
 714         case RXRPC_SUPPORTED_CMSG:
 715                 if (optlen < sizeof(int))
 716                         return -ETOOSMALL;
 717                 if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
 718                     put_user(sizeof(int), _optlen))
 719                         return -EFAULT;
 720                 return 0;
 721
 722         default:
 723                 return -EOPNOTSUPP;
 724         }
 725 }
 726
 727 /*
 728  * permit an RxRPC socket to be polled
 729  */
 730 static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
 731                                poll_table *wait)
 732 {
 733         struct sock *sk = sock->sk;
 734         struct rxrpc_sock *rx = rxrpc_sk(sk);
 735         __poll_t mask;
 736
 737         sock_poll_wait(file, sock, wait);
 738         mask = 0;
 739
 740         /* the socket is readable if there are any messages waiting on the Rx
 741          * queue */
 742         if (!list_empty(&rx->recvmsg_q))
 743                 mask |= EPOLLIN | EPOLLRDNORM;
 744
 745         /* the socket is writable if there is space to add new data to the
 746          * socket; there is no guarantee that any particular call in progress
 747          * on the socket may have space in the Tx ACK window */
 748         if (rxrpc_writable(sk))
 749                 mask |= EPOLLOUT | EPOLLWRNORM;
 750
 751         return mask;
 752 }
 753
 754 /*
 755  * create an RxRPC socket
 756  */
 757 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
 758                         int kern)
 759 {
 760         struct rxrpc_net *rxnet;
 761         struct rxrpc_sock *rx;
 762         struct sock *sk;
 763
 764         _enter("%p,%d", sock, protocol);
 765
 766         /* we support transport protocol UDP/UDP6 only */
 767         if (protocol != PF_INET &&
 768             IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
 769                 return -EPROTONOSUPPORT;
 770
 771         if (sock->type != SOCK_DGRAM)
 772                 return -ESOCKTNOSUPPORT;
 773
 774         sock->ops = &rxrpc_rpc_ops;
 775         sock->state = SS_UNCONNECTED;
 776
 777         sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
 778         if (!sk)
 779                 return -ENOMEM;
 780
 781         sock_init_data(sock, sk);
 782         sock_set_flag(sk, SOCK_RCU_FREE);
 783         sk->sk_state            = RXRPC_UNBOUND;
 784         sk->sk_write_space      = rxrpc_write_space;
 785         sk->sk_max_ack_backlog  = 0;
 786         sk->sk_destruct         = rxrpc_sock_destructor;
 787
 788         rx = rxrpc_sk(sk);
 789         rx->family = protocol;
 790         rx->calls = RB_ROOT;
 791
 792         spin_lock_init(&rx->incoming_lock);
 793         INIT_LIST_HEAD(&rx->sock_calls);
 794         INIT_LIST_HEAD(&rx->to_be_accepted);
 795         INIT_LIST_HEAD(&rx->recvmsg_q);
 796         rwlock_init(&rx->recvmsg_lock);
 797         rwlock_init(&rx->call_lock);
 798         memset(&rx->srx, 0, sizeof(rx->srx));
 799
 800         rxnet = rxrpc_net(sock_net(&rx->sk));
 801         timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
 802
 803         _leave(" = 0 [%p]", rx);
 804         return 0;
 805 }
 806
 807 /*
 808  * Kill all the calls on a socket and shut it down.
 809  */
 810 static int rxrpc_shutdown(struct socket *sock, int flags)
 811 {
 812         struct sock *sk = sock->sk;
 813         struct rxrpc_sock *rx = rxrpc_sk(sk);
 814         int ret = 0;
 815
 816         _enter("%p,%d", sk, flags);
 817
 818         if (flags != SHUT_RDWR)
 819                 return -EOPNOTSUPP;
 820         if (sk->sk_state == RXRPC_CLOSE)
 821                 return -ESHUTDOWN;
 822
 823         lock_sock(sk);
 824
 825         spin_lock_bh(&sk->sk_receive_queue.lock);
 826         if (sk->sk_state < RXRPC_CLOSE) {
 827                 sk->sk_state = RXRPC_CLOSE;
 828                 sk->sk_shutdown = SHUTDOWN_MASK;
 829         } else {
 830                 ret = -ESHUTDOWN;
 831         }
 832         spin_unlock_bh(&sk->sk_receive_queue.lock);
 833
 834         rxrpc_discard_prealloc(rx);
 835
 836         release_sock(sk);
 837         return ret;
 838 }
 839
 840 /*
 841  * RxRPC socket destructor
 842  */
 843 static void rxrpc_sock_destructor(struct sock *sk)
 844 {
 845         _enter("%p", sk);
 846
 847         rxrpc_purge_queue(&sk->sk_receive_queue);
 848
 849         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
 850         WARN_ON(!sk_unhashed(sk));
 851         WARN_ON(sk->sk_socket);
 852
 853         if (!sock_flag(sk, SOCK_DEAD)) {
 854                 printk("Attempt to release alive rxrpc socket: %p\n", sk);
 855                 return;
 856         }
 857 }
 858
 859 /*
 860  * release an RxRPC socket
 861  */
 862 static int rxrpc_release_sock(struct sock *sk)
 863 {
 864         struct rxrpc_sock *rx = rxrpc_sk(sk);
 865
 866         _enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
 867
 868         /* declare the socket closed for business */
 869         sock_orphan(sk);
 870         sk->sk_shutdown = SHUTDOWN_MASK;
 871
 872         /* We want to kill off all connections from a service socket
 873          * as fast as possible because we can't share these; client
 874          * sockets, on the other hand, can share an endpoint.
 875          */
 876         switch (sk->sk_state) {
 877         case RXRPC_SERVER_BOUND:
 878         case RXRPC_SERVER_BOUND2:
 879         case RXRPC_SERVER_LISTENING:
 880         case RXRPC_SERVER_LISTEN_DISABLED:
 881                 rx->local->service_closed = true;
 882                 break;
 883         }
 884
 885         spin_lock_bh(&sk->sk_receive_queue.lock);
 886         sk->sk_state = RXRPC_CLOSE;
 887         spin_unlock_bh(&sk->sk_receive_queue.lock);
 888
 889         if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
 890                 write_lock(&rx->local->services_lock);
 891                 rcu_assign_pointer(rx->local->service, NULL);
 892                 write_unlock(&rx->local->services_lock);
 893         }
 894
 895         /* try to flush out this socket */
 896         rxrpc_discard_prealloc(rx);
 897         rxrpc_release_calls_on_socket(rx);
 898         flush_workqueue(rxrpc_workqueue);
 899         rxrpc_purge_queue(&sk->sk_receive_queue);
 900
 901         rxrpc_unuse_local(rx->local);
 902         rx->local = NULL;
 903         key_put(rx->key);
 904         rx->key = NULL;
 905         key_put(rx->securities);
 906         rx->securities = NULL;
 907         sock_put(sk);
 908
 909         _leave(" = 0");
 910         return 0;
 911 }
 912
 913 /*
 914  * release an RxRPC BSD socket on close() or equivalent
 915  */
 916 static int rxrpc_release(struct socket *sock)
 917 {
 918         struct sock *sk = sock->sk;
 919
 920         _enter("%p{%p}", sock, sk);
 921
 922         if (!sk)
 923                 return 0;
 924
 925         sock->sk = NULL;
 926
 927         return rxrpc_release_sock(sk);
 928 }
 929
 930 /*
 931  * RxRPC network protocol
 932  */
 933 static const struct proto_ops rxrpc_rpc_ops = {
 934         .family         = PF_RXRPC,
 935         .owner          = THIS_MODULE,
 936         .release        = rxrpc_release,
 937         .bind           = rxrpc_bind,
 938         .connect        = rxrpc_connect,
 939         .socketpair     = sock_no_socketpair,
 940         .accept         = sock_no_accept,
 941         .getname        = sock_no_getname,
 942         .poll           = rxrpc_poll,
 943         .ioctl          = sock_no_ioctl,
 944         .listen         = rxrpc_listen,
 945         .shutdown       = rxrpc_shutdown,
 946         .setsockopt     = rxrpc_setsockopt,
 947         .getsockopt     = rxrpc_getsockopt,
 948         .sendmsg        = rxrpc_sendmsg,
 949         .recvmsg        = rxrpc_recvmsg,
 950         .mmap           = sock_no_mmap,
 951         .sendpage       = sock_no_sendpage,
 952 };
 953
 954 static struct proto rxrpc_proto = {
 955         .name           = "RXRPC",
 956         .owner          = THIS_MODULE,
 957         .obj_size       = sizeof(struct rxrpc_sock),
 958         .max_header     = sizeof(struct rxrpc_wire_header),
 959 };
 960
 961 static const struct net_proto_family rxrpc_family_ops = {
 962         .family = PF_RXRPC,
 963         .create = rxrpc_create,
 964         .owner  = THIS_MODULE,
 965 };
 966
 967 /*
 968  * initialise and register the RxRPC protocol
 969  */
 970 static int __init af_rxrpc_init(void)
 971 {
 972         int ret = -1;
 973         unsigned int tmp;
 974
 975         BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
 976
 977         get_random_bytes(&tmp, sizeof(tmp));
 978         tmp &= 0x3fffffff;
 979         if (tmp == 0)
 980                 tmp = 1;
 981         idr_set_cursor(&rxrpc_client_conn_ids, tmp);
 982
 983         ret = -ENOMEM;
 984         rxrpc_call_jar = kmem_cache_create(
 985                 "rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
 986                 SLAB_HWCACHE_ALIGN, NULL);
 987         if (!rxrpc_call_jar) {
 988                 pr_notice("Failed to allocate call jar\n");
 989                 goto error_call_jar;
 990         }
 991
 992         rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
 993         if (!rxrpc_workqueue) {
 994                 pr_notice("Failed to allocate work queue\n");
 995                 goto error_work_queue;
 996         }
 997
 998         ret = rxrpc_init_security();
 999         if (ret < 0) {
1000                 pr_crit("Cannot initialise security\n");
1001                 goto error_security;
1002         }
1003
1004         ret = register_pernet_subsys(&rxrpc_net_ops);
1005         if (ret)
1006                 goto error_pernet;
1007
1008         ret = proto_register(&rxrpc_proto, 1);
1009         if (ret < 0) {
1010                 pr_crit("Cannot register protocol\n");
1011                 goto error_proto;
1012         }
1013
1014         ret = sock_register(&rxrpc_family_ops);
1015         if (ret < 0) {
1016                 pr_crit("Cannot register socket family\n");
1017                 goto error_sock;
1018         }
1019
1020         ret = register_key_type(&key_type_rxrpc);
1021         if (ret < 0) {
1022                 pr_crit("Cannot register client key type\n");
1023                 goto error_key_type;
1024         }
1025
1026         ret = register_key_type(&key_type_rxrpc_s);
1027         if (ret < 0) {
1028                 pr_crit("Cannot register server key type\n");
1029                 goto error_key_type_s;
1030         }
1031
1032         ret = rxrpc_sysctl_init();
1033         if (ret < 0) {
1034                 pr_crit("Cannot register sysctls\n");
1035                 goto error_sysctls;
1036         }
1037
1038         return 0;
1039
1040 error_sysctls:
1041         unregister_key_type(&key_type_rxrpc_s);
1042 error_key_type_s:
1043         unregister_key_type(&key_type_rxrpc);
1044 error_key_type:
1045         sock_unregister(PF_RXRPC);
1046 error_sock:
1047         proto_unregister(&rxrpc_proto);
1048 error_proto:
1049         unregister_pernet_subsys(&rxrpc_net_ops);
1050 error_pernet:
1051         rxrpc_exit_security();
1052 error_security:
1053         destroy_workqueue(rxrpc_workqueue);
1054 error_work_queue:
1055         kmem_cache_destroy(rxrpc_call_jar);
1056 error_call_jar:
1057         return ret;
1058 }
1059
1060 /*
1061  * unregister the RxRPC protocol
1062  */
1063 static void __exit af_rxrpc_exit(void)
1064 {
1065         _enter("");
1066         rxrpc_sysctl_exit();
1067         unregister_key_type(&key_type_rxrpc_s);
1068         unregister_key_type(&key_type_rxrpc);
1069         sock_unregister(PF_RXRPC);
1070         proto_unregister(&rxrpc_proto);
1071         unregister_pernet_subsys(&rxrpc_net_ops);
1072         ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
1073         ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1074
1075         /* Make sure the local and peer records pinned by any dying connections
1076          * are released.
1077          */
1078         rcu_barrier();
1079         rxrpc_destroy_client_conn_ids();
1080
1081         destroy_workqueue(rxrpc_workqueue);
1082         rxrpc_exit_security();
1083         kmem_cache_destroy(rxrpc_call_jar);
1084         _leave("");
1085 }
1086
1087 module_init(af_rxrpc_init);
1088 module_exit(af_rxrpc_exit);