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, 0644);
  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 EXPORT_SYMBOL(rxrpc_debug_id);
  44
  45 /* count of skbs currently in use */
  46 atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_skbs;
  47
  48 struct workqueue_struct *rxrpc_workqueue;
  49
  50 static void rxrpc_sock_destructor(struct sock *);
  51
  52 /*
  53  * see if an RxRPC socket is currently writable
  54  */
  55 static inline int rxrpc_writable(struct sock *sk)
  56 {
  57         return refcount_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
  58 }
  59
  60 /*
  61  * wait for write bufferage to become available
  62  */
  63 static void rxrpc_write_space(struct sock *sk)
  64 {
  65         _enter("%p", sk);
  66         rcu_read_lock();
  67         if (rxrpc_writable(sk)) {
  68                 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
  69
  70                 if (skwq_has_sleeper(wq))
  71                         wake_up_interruptible(&wq->wait);
  72                 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
  73         }
  74         rcu_read_unlock();
  75 }
  76
  77 /*
  78  * validate an RxRPC address
  79  */
  80 static int rxrpc_validate_address(struct rxrpc_sock *rx,
  81                                   struct sockaddr_rxrpc *srx,
  82                                   int len)
  83 {
  84         unsigned int tail;
  85
  86         if (len < sizeof(struct sockaddr_rxrpc))
  87                 return -EINVAL;
  88
  89         if (srx->srx_family != AF_RXRPC)
  90                 return -EAFNOSUPPORT;
  91
  92         if (srx->transport_type != SOCK_DGRAM)
  93                 return -ESOCKTNOSUPPORT;
  94
  95         len -= offsetof(struct sockaddr_rxrpc, transport);
  96         if (srx->transport_len < sizeof(sa_family_t) ||
  97             srx->transport_len > len)
  98                 return -EINVAL;
  99
 100         if (srx->transport.family != rx->family &&
 101             srx->transport.family == AF_INET && rx->family != AF_INET6)
 102                 return -EAFNOSUPPORT;
 103
 104         switch (srx->transport.family) {
 105         case AF_INET:
 106                 if (srx->transport_len < sizeof(struct sockaddr_in))
 107                         return -EINVAL;
 108                 tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
 109                 break;
 110
 111 #ifdef CONFIG_AF_RXRPC_IPV6
 112         case AF_INET6:
 113                 if (srx->transport_len < sizeof(struct sockaddr_in6))
 114                         return -EINVAL;
 115                 tail = offsetof(struct sockaddr_rxrpc, transport) +
 116                         sizeof(struct sockaddr_in6);
 117                 break;
 118 #endif
 119
 120         default:
 121                 return -EAFNOSUPPORT;
 122         }
 123
 124         if (tail < len)
 125                 memset((void *)srx + tail, 0, len - tail);
 126         _debug("INET: %pISp", &srx->transport);
 127         return 0;
 128 }
 129
 130 /*
 131  * bind a local address to an RxRPC socket
 132  */
 133 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
 134 {
 135         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
 136         struct rxrpc_local *local;
 137         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 138         u16 service_id = srx->srx_service;
 139         int ret;
 140
 141         _enter("%p,%p,%d", rx, saddr, len);
 142
 143         ret = rxrpc_validate_address(rx, srx, len);
 144         if (ret < 0)
 145                 goto error;
 146
 147         lock_sock(&rx->sk);
 148
 149         switch (rx->sk.sk_state) {
 150         case RXRPC_UNBOUND:
 151                 rx->srx = *srx;
 152                 local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
 153                 if (IS_ERR(local)) {
 154                         ret = PTR_ERR(local);
 155                         goto error_unlock;
 156                 }
 157
 158                 if (service_id) {
 159                         write_lock(&local->services_lock);
 160                         if (rcu_access_pointer(local->service))
 161                                 goto service_in_use;
 162                         rx->local = local;
 163                         rcu_assign_pointer(local->service, rx);
 164                         write_unlock(&local->services_lock);
 165
 166                         rx->sk.sk_state = RXRPC_SERVER_BOUND;
 167                 } else {
 168                         rx->local = local;
 169                         rx->sk.sk_state = RXRPC_CLIENT_BOUND;
 170                 }
 171                 break;
 172
 173         case RXRPC_SERVER_BOUND:
 174                 ret = -EINVAL;
 175                 if (service_id == 0)
 176                         goto error_unlock;
 177                 ret = -EADDRINUSE;
 178                 if (service_id == rx->srx.srx_service)
 179                         goto error_unlock;
 180                 ret = -EINVAL;
 181                 srx->srx_service = rx->srx.srx_service;
 182                 if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0)
 183                         goto error_unlock;
 184                 rx->second_service = service_id;
 185                 rx->sk.sk_state = RXRPC_SERVER_BOUND2;
 186                 break;
 187
 188         default:
 189                 ret = -EINVAL;
 190                 goto error_unlock;
 191         }
 192
 193         release_sock(&rx->sk);
 194         _leave(" = 0");
 195         return 0;
 196
 197 service_in_use:
 198         write_unlock(&local->services_lock);
 199         rxrpc_put_local(local);
 200         ret = -EADDRINUSE;
 201 error_unlock:
 202         release_sock(&rx->sk);
 203 error:
 204         _leave(" = %d", ret);
 205         return ret;
 206 }
 207
 208 /*
 209  * set the number of pending calls permitted on a listening socket
 210  */
 211 static int rxrpc_listen(struct socket *sock, int backlog)
 212 {
 213         struct sock *sk = sock->sk;
 214         struct rxrpc_sock *rx = rxrpc_sk(sk);
 215         unsigned int max, old;
 216         int ret;
 217
 218         _enter("%p,%d", rx, backlog);
 219
 220         lock_sock(&rx->sk);
 221
 222         switch (rx->sk.sk_state) {
 223         case RXRPC_UNBOUND:
 224                 ret = -EADDRNOTAVAIL;
 225                 break;
 226         case RXRPC_SERVER_BOUND:
 227         case RXRPC_SERVER_BOUND2:
 228                 ASSERT(rx->local != NULL);
 229                 max = READ_ONCE(rxrpc_max_backlog);
 230                 ret = -EINVAL;
 231                 if (backlog == INT_MAX)
 232                         backlog = max;
 233                 else if (backlog < 0 || backlog > max)
 234                         break;
 235                 old = sk->sk_max_ack_backlog;
 236                 sk->sk_max_ack_backlog = backlog;
 237                 ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
 238                 if (ret == 0)
 239                         rx->sk.sk_state = RXRPC_SERVER_LISTENING;
 240                 else
 241                         sk->sk_max_ack_backlog = old;
 242                 break;
 243         case RXRPC_SERVER_LISTENING:
 244                 if (backlog == 0) {
 245                         rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED;
 246                         sk->sk_max_ack_backlog = 0;
 247                         rxrpc_discard_prealloc(rx);
 248                         ret = 0;
 249                         break;
 250                 }
 251                 /* Fall through */
 252         default:
 253                 ret = -EBUSY;
 254                 break;
 255         }
 256
 257         release_sock(&rx->sk);
 258         _leave(" = %d", ret);
 259         return ret;
 260 }
 261
 262 /**
 263  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
 264  * @sock: The socket on which to make the call
 265  * @srx: The address of the peer to contact
 266  * @key: The security context to use (defaults to socket setting)
 267  * @user_call_ID: The ID to use
 268  * @tx_total_len: Total length of data to transmit during the call (or -1)
 269  * @gfp: The allocation constraints
 270  * @notify_rx: Where to send notifications instead of socket queue
 271  * @upgrade: Request service upgrade for call
 272  * @debug_id: The debug ID for tracing to be assigned to the call
 273  *
 274  * Allow a kernel service to begin a call on the nominated socket.  This just
 275  * sets up all the internal tracking structures and allocates connection and
 276  * call IDs as appropriate.  The call to be used is returned.
 277  *
 278  * The default socket destination address and security may be overridden by
 279  * supplying @srx and @key.
 280  */
 281 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 282                                            struct sockaddr_rxrpc *srx,
 283                                            struct key *key,
 284                                            unsigned long user_call_ID,
 285                                            s64 tx_total_len,
 286                                            gfp_t gfp,
 287                                            rxrpc_notify_rx_t notify_rx,
 288                                            bool upgrade,
 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
 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  *
 374  * Allow a kernel service to find out whether a call is still alive - ie. we're
 375  * getting ACKs from the server.  Returns a number representing the life state
 376  * which can be compared to that returned by a previous call.
 377  *
 378  * If the life state stalls, rxrpc_kernel_probe_life() should be called and
 379  * then 2RTT waited.
 380  */
 381 u32 rxrpc_kernel_check_life(const struct socket *sock,
 382                             const struct rxrpc_call *call)
 383 {
 384         return call->acks_latest;
 385 }
 386 EXPORT_SYMBOL(rxrpc_kernel_check_life);
 387
 388 /**
 389  * rxrpc_kernel_probe_life - Poke the peer to see if it's still alive
 390  * @sock: The socket the call is on
 391  * @call: The call to check
 392  *
 393  * In conjunction with rxrpc_kernel_check_life(), allow a kernel service to
 394  * find out whether a call is still alive by pinging it.  This should cause the
 395  * life state to be bumped in about 2*RTT.
 396  *
 397  * The must be called in TASK_RUNNING state on pain of might_sleep() objecting.
 398  */
 399 void rxrpc_kernel_probe_life(struct socket *sock, struct rxrpc_call *call)
 400 {
 401         rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false,
 402                           rxrpc_propose_ack_ping_for_check_life);
 403         rxrpc_send_ack_packet(call, true, NULL);
 404 }
 405 EXPORT_SYMBOL(rxrpc_kernel_probe_life);
 406
 407 /**
 408  * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
 409  * @sock: The socket the call is on
 410  * @call: The call to query
 411  *
 412  * Allow a kernel service to retrieve the epoch value from a service call to
 413  * see if the client at the other end rebooted.
 414  */
 415 u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
 416 {
 417         return call->conn->proto.epoch;
 418 }
 419 EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
 420
 421 /**
 422  * rxrpc_kernel_check_call - Check a call's state
 423  * @sock: The socket the call is on
 424  * @call: The call to check
 425  * @_compl: Where to store the completion state
 426  * @_abort_code: Where to store any abort code
 427  *
 428  * Allow a kernel service to query the state of a call and find out the manner
 429  * of its termination if it has completed.  Returns -EINPROGRESS if the call is
 430  * still going, 0 if the call finished successfully, -ECONNABORTED if the call
 431  * was aborted and an appropriate error if the call failed in some other way.
 432  */
 433 int rxrpc_kernel_check_call(struct socket *sock, struct rxrpc_call *call,
 434                             enum rxrpc_call_completion *_compl, u32 *_abort_code)
 435 {
 436         if (call->state != RXRPC_CALL_COMPLETE)
 437                 return -EINPROGRESS;
 438         smp_rmb();
 439         *_compl = call->completion;
 440         *_abort_code = call->abort_code;
 441         return call->error;
 442 }
 443 EXPORT_SYMBOL(rxrpc_kernel_check_call);
 444
 445 /**
 446  * rxrpc_kernel_retry_call - Allow a kernel service to retry a call
 447  * @sock: The socket the call is on
 448  * @call: The call to retry
 449  * @srx: The address of the peer to contact
 450  * @key: The security context to use (defaults to socket setting)
 451  *
 452  * Allow a kernel service to try resending a client call that failed due to a
 453  * network error to a new address.  The Tx queue is maintained intact, thereby
 454  * relieving the need to re-encrypt any request data that has already been
 455  * buffered.
 456  */
 457 int rxrpc_kernel_retry_call(struct socket *sock, struct rxrpc_call *call,
 458                             struct sockaddr_rxrpc *srx, struct key *key)
 459 {
 460         struct rxrpc_conn_parameters cp;
 461         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 462         int ret;
 463
 464         _enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
 465
 466         if (!key)
 467                 key = rx->key;
 468         if (key && !key->payload.data[0])
 469                 key = NULL; /* a no-security key */
 470
 471         memset(&cp, 0, sizeof(cp));
 472         cp.local                = rx->local;
 473         cp.key                  = key;
 474         cp.security_level       = 0;
 475         cp.exclusive            = false;
 476         cp.service_id           = srx->srx_service;
 477
 478         mutex_lock(&call->user_mutex);
 479
 480         ret = rxrpc_prepare_call_for_retry(rx, call);
 481         if (ret == 0)
 482                 ret = rxrpc_retry_client_call(rx, call, &cp, srx, GFP_KERNEL);
 483
 484         mutex_unlock(&call->user_mutex);
 485         rxrpc_put_peer(cp.peer);
 486         _leave(" = %d", ret);
 487         return ret;
 488 }
 489 EXPORT_SYMBOL(rxrpc_kernel_retry_call);
 490
 491 /**
 492  * rxrpc_kernel_new_call_notification - Get notifications of new calls
 493  * @sock: The socket to intercept received messages on
 494  * @notify_new_call: Function to be called when new calls appear
 495  * @discard_new_call: Function to discard preallocated calls
 496  *
 497  * Allow a kernel service to be given notifications about new calls.
 498  */
 499 void rxrpc_kernel_new_call_notification(
 500         struct socket *sock,
 501         rxrpc_notify_new_call_t notify_new_call,
 502         rxrpc_discard_new_call_t discard_new_call)
 503 {
 504         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 505
 506         rx->notify_new_call = notify_new_call;
 507         rx->discard_new_call = discard_new_call;
 508 }
 509 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
 510
 511 /*
 512  * connect an RxRPC socket
 513  * - this just targets it at a specific destination; no actual connection
 514  *   negotiation takes place
 515  */
 516 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
 517                          int addr_len, int flags)
 518 {
 519         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
 520         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 521         int ret;
 522
 523         _enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
 524
 525         ret = rxrpc_validate_address(rx, srx, addr_len);
 526         if (ret < 0) {
 527                 _leave(" = %d [bad addr]", ret);
 528                 return ret;
 529         }
 530
 531         lock_sock(&rx->sk);
 532
 533         ret = -EISCONN;
 534         if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
 535                 goto error;
 536
 537         switch (rx->sk.sk_state) {
 538         case RXRPC_UNBOUND:
 539                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 540         case RXRPC_CLIENT_UNBOUND:
 541         case RXRPC_CLIENT_BOUND:
 542                 break;
 543         default:
 544                 ret = -EBUSY;
 545                 goto error;
 546         }
 547
 548         rx->connect_srx = *srx;
 549         set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
 550         ret = 0;
 551
 552 error:
 553         release_sock(&rx->sk);
 554         return ret;
 555 }
 556
 557 /*
 558  * send a message through an RxRPC socket
 559  * - in a client this does a number of things:
 560  *   - finds/sets up a connection for the security specified (if any)
 561  *   - initiates a call (ID in control data)
 562  *   - ends the request phase of a call (if MSG_MORE is not set)
 563  *   - sends a call data packet
 564  *   - may send an abort (abort code in control data)
 565  */
 566 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
 567 {
 568         struct rxrpc_local *local;
 569         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 570         int ret;
 571
 572         _enter(",{%d},,%zu", rx->sk.sk_state, len);
 573
 574         if (m->msg_flags & MSG_OOB)
 575                 return -EOPNOTSUPP;
 576
 577         if (m->msg_name) {
 578                 ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
 579                 if (ret < 0) {
 580                         _leave(" = %d [bad addr]", ret);
 581                         return ret;
 582                 }
 583         }
 584
 585         lock_sock(&rx->sk);
 586
 587         switch (rx->sk.sk_state) {
 588         case RXRPC_UNBOUND:
 589                 rx->srx.srx_family = AF_RXRPC;
 590                 rx->srx.srx_service = 0;
 591                 rx->srx.transport_type = SOCK_DGRAM;
 592                 rx->srx.transport.family = rx->family;
 593                 switch (rx->family) {
 594                 case AF_INET:
 595                         rx->srx.transport_len = sizeof(struct sockaddr_in);
 596                         break;
 597 #ifdef CONFIG_AF_RXRPC_IPV6
 598                 case AF_INET6:
 599                         rx->srx.transport_len = sizeof(struct sockaddr_in6);
 600                         break;
 601 #endif
 602                 default:
 603                         ret = -EAFNOSUPPORT;
 604                         goto error_unlock;
 605                 }
 606                 local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
 607                 if (IS_ERR(local)) {
 608                         ret = PTR_ERR(local);
 609                         goto error_unlock;
 610                 }
 611
 612                 rx->local = local;
 613                 rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
 614                 /* Fall through */
 615
 616         case RXRPC_CLIENT_UNBOUND:
 617         case RXRPC_CLIENT_BOUND:
 618                 if (!m->msg_name &&
 619                     test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
 620                         m->msg_name = &rx->connect_srx;
 621                         m->msg_namelen = sizeof(rx->connect_srx);
 622                 }
 623                 /* Fall through */
 624         case RXRPC_SERVER_BOUND:
 625         case RXRPC_SERVER_LISTENING:
 626                 ret = rxrpc_do_sendmsg(rx, m, len);
 627                 /* The socket has been unlocked */
 628                 goto out;
 629         default:
 630                 ret = -EINVAL;
 631                 goto error_unlock;
 632         }
 633
 634 error_unlock:
 635         release_sock(&rx->sk);
 636 out:
 637         _leave(" = %d", ret);
 638         return ret;
 639 }
 640
 641 /*
 642  * set RxRPC socket options
 643  */
 644 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
 645                             char __user *optval, unsigned int optlen)
 646 {
 647         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
 648         unsigned int min_sec_level;
 649         u16 service_upgrade[2];
 650         int ret;
 651
 652         _enter(",%d,%d,,%d", level, optname, optlen);
 653
 654         lock_sock(&rx->sk);
 655         ret = -EOPNOTSUPP;
 656
 657         if (level == SOL_RXRPC) {
 658                 switch (optname) {
 659                 case RXRPC_EXCLUSIVE_CONNECTION:
 660                         ret = -EINVAL;
 661                         if (optlen != 0)
 662                                 goto error;
 663                         ret = -EISCONN;
 664                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 665                                 goto error;
 666                         rx->exclusive = true;
 667                         goto success;
 668
 669                 case RXRPC_SECURITY_KEY:
 670                         ret = -EINVAL;
 671                         if (rx->key)
 672                                 goto error;
 673                         ret = -EISCONN;
 674                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 675                                 goto error;
 676                         ret = rxrpc_request_key(rx, optval, optlen);
 677                         goto error;
 678
 679                 case RXRPC_SECURITY_KEYRING:
 680                         ret = -EINVAL;
 681                         if (rx->key)
 682                                 goto error;
 683                         ret = -EISCONN;
 684                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 685                                 goto error;
 686                         ret = rxrpc_server_keyring(rx, optval, optlen);
 687                         goto error;
 688
 689                 case RXRPC_MIN_SECURITY_LEVEL:
 690                         ret = -EINVAL;
 691                         if (optlen != sizeof(unsigned int))
 692                                 goto error;
 693                         ret = -EISCONN;
 694                         if (rx->sk.sk_state != RXRPC_UNBOUND)
 695                                 goto error;
 696                         ret = get_user(min_sec_level,
 697                                        (unsigned int __user *) optval);
 698                         if (ret < 0)
 699                                 goto error;
 700                         ret = -EINVAL;
 701                         if (min_sec_level > RXRPC_SECURITY_MAX)
 702                                 goto error;
 703                         rx->min_sec_level = min_sec_level;
 704                         goto success;
 705
 706                 case RXRPC_UPGRADEABLE_SERVICE:
 707                         ret = -EINVAL;
 708                         if (optlen != sizeof(service_upgrade) ||
 709                             rx->service_upgrade.from != 0)
 710                                 goto error;
 711                         ret = -EISCONN;
 712                         if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
 713                                 goto error;
 714                         ret = -EFAULT;
 715                         if (copy_from_user(service_upgrade, optval,
 716                                            sizeof(service_upgrade)) != 0)
 717                                 goto error;
 718                         ret = -EINVAL;
 719                         if ((service_upgrade[0] != rx->srx.srx_service ||
 720                              service_upgrade[1] != rx->second_service) &&
 721                             (service_upgrade[0] != rx->second_service ||
 722                              service_upgrade[1] != rx->srx.srx_service))
 723                                 goto error;
 724                         rx->service_upgrade.from = service_upgrade[0];
 725                         rx->service_upgrade.to = service_upgrade[1];
 726                         goto success;
 727
 728                 default:
 729                         break;
 730                 }
 731         }
 732
 733 success:
 734         ret = 0;
 735 error:
 736         release_sock(&rx->sk);
 737         return ret;
 738 }
 739
 740 /*
 741  * Get socket options.
 742  */
 743 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
 744                             char __user *optval, int __user *_optlen)
 745 {
 746         int optlen;
 747
 748         if (level != SOL_RXRPC)
 749                 return -EOPNOTSUPP;
 750
 751         if (get_user(optlen, _optlen))
 752                 return -EFAULT;
 753
 754         switch (optname) {
 755         case RXRPC_SUPPORTED_CMSG:
 756                 if (optlen < sizeof(int))
 757                         return -ETOOSMALL;
 758                 if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
 759                     put_user(sizeof(int), _optlen))
 760                         return -EFAULT;
 761                 return 0;
 762
 763         default:
 764                 return -EOPNOTSUPP;
 765         }
 766 }
 767
 768 /*
 769  * permit an RxRPC socket to be polled
 770  */
 771 static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
 772                                poll_table *wait)
 773 {
 774         struct sock *sk = sock->sk;
 775         struct rxrpc_sock *rx = rxrpc_sk(sk);
 776         __poll_t mask;
 777
 778         sock_poll_wait(file, sock, wait);
 779         mask = 0;
 780
 781         /* the socket is readable if there are any messages waiting on the Rx
 782          * queue */
 783         if (!list_empty(&rx->recvmsg_q))
 784                 mask |= EPOLLIN | EPOLLRDNORM;
 785
 786         /* the socket is writable if there is space to add new data to the
 787          * socket; there is no guarantee that any particular call in progress
 788          * on the socket may have space in the Tx ACK window */
 789         if (rxrpc_writable(sk))
 790                 mask |= EPOLLOUT | EPOLLWRNORM;
 791
 792         return mask;
 793 }
 794
 795 /*
 796  * create an RxRPC socket
 797  */
 798 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
 799                         int kern)
 800 {
 801         struct rxrpc_net *rxnet;
 802         struct rxrpc_sock *rx;
 803         struct sock *sk;
 804
 805         _enter("%p,%d", sock, protocol);
 806
 807         /* we support transport protocol UDP/UDP6 only */
 808         if (protocol != PF_INET &&
 809             IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
 810                 return -EPROTONOSUPPORT;
 811
 812         if (sock->type != SOCK_DGRAM)
 813                 return -ESOCKTNOSUPPORT;
 814
 815         sock->ops = &rxrpc_rpc_ops;
 816         sock->state = SS_UNCONNECTED;
 817
 818         sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
 819         if (!sk)
 820                 return -ENOMEM;
 821
 822         sock_init_data(sock, sk);
 823         sock_set_flag(sk, SOCK_RCU_FREE);
 824         sk->sk_state            = RXRPC_UNBOUND;
 825         sk->sk_write_space      = rxrpc_write_space;
 826         sk->sk_max_ack_backlog  = 0;
 827         sk->sk_destruct         = rxrpc_sock_destructor;
 828
 829         rx = rxrpc_sk(sk);
 830         rx->family = protocol;
 831         rx->calls = RB_ROOT;
 832
 833         spin_lock_init(&rx->incoming_lock);
 834         INIT_LIST_HEAD(&rx->sock_calls);
 835         INIT_LIST_HEAD(&rx->to_be_accepted);
 836         INIT_LIST_HEAD(&rx->recvmsg_q);
 837         rwlock_init(&rx->recvmsg_lock);
 838         rwlock_init(&rx->call_lock);
 839         memset(&rx->srx, 0, sizeof(rx->srx));
 840
 841         rxnet = rxrpc_net(sock_net(&rx->sk));
 842         timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
 843
 844         _leave(" = 0 [%p]", rx);
 845         return 0;
 846 }
 847
 848 /*
 849  * Kill all the calls on a socket and shut it down.
 850  */
 851 static int rxrpc_shutdown(struct socket *sock, int flags)
 852 {
 853         struct sock *sk = sock->sk;
 854         struct rxrpc_sock *rx = rxrpc_sk(sk);
 855         int ret = 0;
 856
 857         _enter("%p,%d", sk, flags);
 858
 859         if (flags != SHUT_RDWR)
 860                 return -EOPNOTSUPP;
 861         if (sk->sk_state == RXRPC_CLOSE)
 862                 return -ESHUTDOWN;
 863
 864         lock_sock(sk);
 865
 866         spin_lock_bh(&sk->sk_receive_queue.lock);
 867         if (sk->sk_state < RXRPC_CLOSE) {
 868                 sk->sk_state = RXRPC_CLOSE;
 869                 sk->sk_shutdown = SHUTDOWN_MASK;
 870         } else {
 871                 ret = -ESHUTDOWN;
 872         }
 873         spin_unlock_bh(&sk->sk_receive_queue.lock);
 874
 875         rxrpc_discard_prealloc(rx);
 876
 877         release_sock(sk);
 878         return ret;
 879 }
 880
 881 /*
 882  * RxRPC socket destructor
 883  */
 884 static void rxrpc_sock_destructor(struct sock *sk)
 885 {
 886         _enter("%p", sk);
 887
 888         rxrpc_purge_queue(&sk->sk_receive_queue);
 889
 890         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
 891         WARN_ON(!sk_unhashed(sk));
 892         WARN_ON(sk->sk_socket);
 893
 894         if (!sock_flag(sk, SOCK_DEAD)) {
 895                 printk("Attempt to release alive rxrpc socket: %p\n", sk);
 896                 return;
 897         }
 898 }
 899
 900 /*
 901  * release an RxRPC socket
 902  */
 903 static int rxrpc_release_sock(struct sock *sk)
 904 {
 905         struct rxrpc_sock *rx = rxrpc_sk(sk);
 906         struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
 907
 908         _enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
 909
 910         /* declare the socket closed for business */
 911         sock_orphan(sk);
 912         sk->sk_shutdown = SHUTDOWN_MASK;
 913
 914         /* We want to kill off all connections from a service socket
 915          * as fast as possible because we can't share these; client
 916          * sockets, on the other hand, can share an endpoint.
 917          */
 918         switch (sk->sk_state) {
 919         case RXRPC_SERVER_BOUND:
 920         case RXRPC_SERVER_BOUND2:
 921         case RXRPC_SERVER_LISTENING:
 922         case RXRPC_SERVER_LISTEN_DISABLED:
 923                 rx->local->service_closed = true;
 924                 break;
 925         }
 926
 927         spin_lock_bh(&sk->sk_receive_queue.lock);
 928         sk->sk_state = RXRPC_CLOSE;
 929         spin_unlock_bh(&sk->sk_receive_queue.lock);
 930
 931         if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
 932                 write_lock(&rx->local->services_lock);
 933                 rcu_assign_pointer(rx->local->service, NULL);
 934                 write_unlock(&rx->local->services_lock);
 935         }
 936
 937         /* try to flush out this socket */
 938         rxrpc_discard_prealloc(rx);
 939         rxrpc_release_calls_on_socket(rx);
 940         flush_workqueue(rxrpc_workqueue);
 941         rxrpc_purge_queue(&sk->sk_receive_queue);
 942         rxrpc_queue_work(&rxnet->service_conn_reaper);
 943         rxrpc_queue_work(&rxnet->client_conn_reaper);
 944
 945         rxrpc_put_local(rx->local);
 946         rx->local = NULL;
 947         key_put(rx->key);
 948         rx->key = NULL;
 949         key_put(rx->securities);
 950         rx->securities = NULL;
 951         sock_put(sk);
 952
 953         _leave(" = 0");
 954         return 0;
 955 }
 956
 957 /*
 958  * release an RxRPC BSD socket on close() or equivalent
 959  */
 960 static int rxrpc_release(struct socket *sock)
 961 {
 962         struct sock *sk = sock->sk;
 963
 964         _enter("%p{%p}", sock, sk);
 965
 966         if (!sk)
 967                 return 0;
 968
 969         sock->sk = NULL;
 970
 971         return rxrpc_release_sock(sk);
 972 }
 973
 974 /*
 975  * RxRPC network protocol
 976  */
 977 static const struct proto_ops rxrpc_rpc_ops = {
 978         .family         = PF_RXRPC,
 979         .owner          = THIS_MODULE,
 980         .release        = rxrpc_release,
 981         .bind           = rxrpc_bind,
 982         .connect        = rxrpc_connect,
 983         .socketpair     = sock_no_socketpair,
 984         .accept         = sock_no_accept,
 985         .getname        = sock_no_getname,
 986         .poll           = rxrpc_poll,
 987         .ioctl          = sock_no_ioctl,
 988         .listen         = rxrpc_listen,
 989         .shutdown       = rxrpc_shutdown,
 990         .setsockopt     = rxrpc_setsockopt,
 991         .getsockopt     = rxrpc_getsockopt,
 992         .sendmsg        = rxrpc_sendmsg,
 993         .recvmsg        = rxrpc_recvmsg,
 994         .mmap           = sock_no_mmap,
 995         .sendpage       = sock_no_sendpage,
 996 };
 997
 998 static struct proto rxrpc_proto = {
 999         .name           = "RXRPC",
1000         .owner          = THIS_MODULE,
1001         .obj_size       = sizeof(struct rxrpc_sock),
1002         .max_header     = sizeof(struct rxrpc_wire_header),
1003 };
1004
1005 static const struct net_proto_family rxrpc_family_ops = {
1006         .family = PF_RXRPC,
1007         .create = rxrpc_create,
1008         .owner  = THIS_MODULE,
1009 };
1010
1011 /*
1012  * initialise and register the RxRPC protocol
1013  */
1014 static int __init af_rxrpc_init(void)
1015 {
1016         int ret = -1;
1017         unsigned int tmp;
1018
1019         BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
1020
1021         get_random_bytes(&tmp, sizeof(tmp));
1022         tmp &= 0x3fffffff;
1023         if (tmp == 0)
1024                 tmp = 1;
1025         idr_set_cursor(&rxrpc_client_conn_ids, tmp);
1026
1027         ret = -ENOMEM;
1028         rxrpc_call_jar = kmem_cache_create(
1029                 "rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
1030                 SLAB_HWCACHE_ALIGN, NULL);
1031         if (!rxrpc_call_jar) {
1032                 pr_notice("Failed to allocate call jar\n");
1033                 goto error_call_jar;
1034         }
1035
1036         rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
1037         if (!rxrpc_workqueue) {
1038                 pr_notice("Failed to allocate work queue\n");
1039                 goto error_work_queue;
1040         }
1041
1042         ret = rxrpc_init_security();
1043         if (ret < 0) {
1044                 pr_crit("Cannot initialise security\n");
1045                 goto error_security;
1046         }
1047
1048         ret = register_pernet_subsys(&rxrpc_net_ops);
1049         if (ret)
1050                 goto error_pernet;
1051
1052         ret = proto_register(&rxrpc_proto, 1);
1053         if (ret < 0) {
1054                 pr_crit("Cannot register protocol\n");
1055                 goto error_proto;
1056         }
1057
1058         ret = sock_register(&rxrpc_family_ops);
1059         if (ret < 0) {
1060                 pr_crit("Cannot register socket family\n");
1061                 goto error_sock;
1062         }
1063
1064         ret = register_key_type(&key_type_rxrpc);
1065         if (ret < 0) {
1066                 pr_crit("Cannot register client key type\n");
1067                 goto error_key_type;
1068         }
1069
1070         ret = register_key_type(&key_type_rxrpc_s);
1071         if (ret < 0) {
1072                 pr_crit("Cannot register server key type\n");
1073                 goto error_key_type_s;
1074         }
1075
1076         ret = rxrpc_sysctl_init();
1077         if (ret < 0) {
1078                 pr_crit("Cannot register sysctls\n");
1079                 goto error_sysctls;
1080         }
1081
1082         return 0;
1083
1084 error_sysctls:
1085         unregister_key_type(&key_type_rxrpc_s);
1086 error_key_type_s:
1087         unregister_key_type(&key_type_rxrpc);
1088 error_key_type:
1089         sock_unregister(PF_RXRPC);
1090 error_sock:
1091         proto_unregister(&rxrpc_proto);
1092 error_proto:
1093         unregister_pernet_subsys(&rxrpc_net_ops);
1094 error_pernet:
1095         rxrpc_exit_security();
1096 error_security:
1097         destroy_workqueue(rxrpc_workqueue);
1098 error_work_queue:
1099         kmem_cache_destroy(rxrpc_call_jar);
1100 error_call_jar:
1101         return ret;
1102 }
1103
1104 /*
1105  * unregister the RxRPC protocol
1106  */
1107 static void __exit af_rxrpc_exit(void)
1108 {
1109         _enter("");
1110         rxrpc_sysctl_exit();
1111         unregister_key_type(&key_type_rxrpc_s);
1112         unregister_key_type(&key_type_rxrpc);
1113         sock_unregister(PF_RXRPC);
1114         proto_unregister(&rxrpc_proto);
1115         unregister_pernet_subsys(&rxrpc_net_ops);
1116         ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
1117         ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1118
1119         /* Make sure the local and peer records pinned by any dying connections
1120          * are released.
1121          */
1122         rcu_barrier();
1123         rxrpc_destroy_client_conn_ids();
1124
1125         destroy_workqueue(rxrpc_workqueue);
1126         rxrpc_exit_security();
1127         kmem_cache_destroy(rxrpc_call_jar);
1128         _leave("");
1129 }
1130
1131 module_init(af_rxrpc_init);
1132 module_exit(af_rxrpc_exit);