net/vmw_vsock/vmci_transport.c

   1 /*
   2  * VMware vSockets Driver
   3  *
   4  * Copyright (C) 2007-2013 VMware, Inc. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation version 2 and no later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 #include <linux/types.h>
  17 #include <linux/bitops.h>
  18 #include <linux/cred.h>
  19 #include <linux/init.h>
  20 #include <linux/io.h>
  21 #include <linux/kernel.h>
  22 #include <linux/kmod.h>
  23 #include <linux/list.h>
  24 #include <linux/miscdevice.h>
  25 #include <linux/module.h>
  26 #include <linux/mutex.h>
  27 #include <linux/net.h>
  28 #include <linux/poll.h>
  29 #include <linux/skbuff.h>
  30 #include <linux/smp.h>
  31 #include <linux/socket.h>
  32 #include <linux/stddef.h>
  33 #include <linux/unistd.h>
  34 #include <linux/wait.h>
  35 #include <linux/workqueue.h>
  36 #include <net/sock.h>
  37 #include <net/af_vsock.h>
  38
  39 #include "vmci_transport_notify.h"
  40
  41 static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg);
  42 static int vmci_transport_recv_stream_cb(void *data, struct vmci_datagram *dg);
  43 static void vmci_transport_peer_attach_cb(u32 sub_id,
  44                                           const struct vmci_event_data *ed,
  45                                           void *client_data);
  46 static void vmci_transport_peer_detach_cb(u32 sub_id,
  47                                           const struct vmci_event_data *ed,
  48                                           void *client_data);
  49 static void vmci_transport_recv_pkt_work(struct work_struct *work);
  50 static int vmci_transport_recv_listen(struct sock *sk,
  51                                       struct vmci_transport_packet *pkt);
  52 static int vmci_transport_recv_connecting_server(
  53                                         struct sock *sk,
  54                                         struct sock *pending,
  55                                         struct vmci_transport_packet *pkt);
  56 static int vmci_transport_recv_connecting_client(
  57                                         struct sock *sk,
  58                                         struct vmci_transport_packet *pkt);
  59 static int vmci_transport_recv_connecting_client_negotiate(
  60                                         struct sock *sk,
  61                                         struct vmci_transport_packet *pkt);
  62 static int vmci_transport_recv_connecting_client_invalid(
  63                                         struct sock *sk,
  64                                         struct vmci_transport_packet *pkt);
  65 static int vmci_transport_recv_connected(struct sock *sk,
  66                                          struct vmci_transport_packet *pkt);
  67 static bool vmci_transport_old_proto_override(bool *old_pkt_proto);
  68 static u16 vmci_transport_new_proto_supported_versions(void);
  69 static bool vmci_transport_proto_to_notify_struct(struct sock *sk, u16 *proto,
  70                                                   bool old_pkt_proto);
  71
  72 struct vmci_transport_recv_pkt_info {
  73         struct work_struct work;
  74         struct sock *sk;
  75         struct vmci_transport_packet pkt;
  76 };
  77
  78 static struct vmci_handle vmci_transport_stream_handle = { VMCI_INVALID_ID,
  79                                                            VMCI_INVALID_ID };
  80 static u32 vmci_transport_qp_resumed_sub_id = VMCI_INVALID_ID;
  81
  82 static int PROTOCOL_OVERRIDE = -1;
  83
  84 #define VMCI_TRANSPORT_DEFAULT_QP_SIZE_MIN   128
  85 #define VMCI_TRANSPORT_DEFAULT_QP_SIZE       262144
  86 #define VMCI_TRANSPORT_DEFAULT_QP_SIZE_MAX   262144
  87
  88 /* The default peer timeout indicates how long we will wait for a peer response
  89  * to a control message.
  90  */
  91 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ)
  92
  93 #define SS_LISTEN 255
  94
  95 /* Helper function to convert from a VMCI error code to a VSock error code. */
  96
  97 static s32 vmci_transport_error_to_vsock_error(s32 vmci_error)
  98 {
  99         int err;
 100
 101         switch (vmci_error) {
 102         case VMCI_ERROR_NO_MEM:
 103                 err = ENOMEM;
 104                 break;
 105         case VMCI_ERROR_DUPLICATE_ENTRY:
 106         case VMCI_ERROR_ALREADY_EXISTS:
 107                 err = EADDRINUSE;
 108                 break;
 109         case VMCI_ERROR_NO_ACCESS:
 110                 err = EPERM;
 111                 break;
 112         case VMCI_ERROR_NO_RESOURCES:
 113                 err = ENOBUFS;
 114                 break;
 115         case VMCI_ERROR_INVALID_RESOURCE:
 116                 err = EHOSTUNREACH;
 117                 break;
 118         case VMCI_ERROR_INVALID_ARGS:
 119         default:
 120                 err = EINVAL;
 121         }
 122
 123         return err > 0 ? -err : err;
 124 }
 125
 126 static u32 vmci_transport_peer_rid(u32 peer_cid)
 127 {
 128         if (VMADDR_CID_HYPERVISOR == peer_cid)
 129                 return VMCI_TRANSPORT_HYPERVISOR_PACKET_RID;
 130
 131         return VMCI_TRANSPORT_PACKET_RID;
 132 }
 133
 134 static inline void
 135 vmci_transport_packet_init(struct vmci_transport_packet *pkt,
 136                            struct sockaddr_vm *src,
 137                            struct sockaddr_vm *dst,
 138                            u8 type,
 139                            u64 size,
 140                            u64 mode,
 141                            struct vmci_transport_waiting_info *wait,
 142                            u16 proto,
 143                            struct vmci_handle handle)
 144 {
 145         /* We register the stream control handler as an any cid handle so we
 146          * must always send from a source address of VMADDR_CID_ANY
 147          */
 148         pkt->dg.src = vmci_make_handle(VMADDR_CID_ANY,
 149                                        VMCI_TRANSPORT_PACKET_RID);
 150         pkt->dg.dst = vmci_make_handle(dst->svm_cid,
 151                                        vmci_transport_peer_rid(dst->svm_cid));
 152         pkt->dg.payload_size = sizeof(*pkt) - sizeof(pkt->dg);
 153         pkt->version = VMCI_TRANSPORT_PACKET_VERSION;
 154         pkt->type = type;
 155         pkt->src_port = src->svm_port;
 156         pkt->dst_port = dst->svm_port;
 157         memset(&pkt->proto, 0, sizeof(pkt->proto));
 158         memset(&pkt->_reserved2, 0, sizeof(pkt->_reserved2));
 159
 160         switch (pkt->type) {
 161         case VMCI_TRANSPORT_PACKET_TYPE_INVALID:
 162                 pkt->u.size = 0;
 163                 break;
 164
 165         case VMCI_TRANSPORT_PACKET_TYPE_REQUEST:
 166         case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE:
 167                 pkt->u.size = size;
 168                 break;
 169
 170         case VMCI_TRANSPORT_PACKET_TYPE_OFFER:
 171         case VMCI_TRANSPORT_PACKET_TYPE_ATTACH:
 172                 pkt->u.handle = handle;
 173                 break;
 174
 175         case VMCI_TRANSPORT_PACKET_TYPE_WROTE:
 176         case VMCI_TRANSPORT_PACKET_TYPE_READ:
 177         case VMCI_TRANSPORT_PACKET_TYPE_RST:
 178                 pkt->u.size = 0;
 179                 break;
 180
 181         case VMCI_TRANSPORT_PACKET_TYPE_SHUTDOWN:
 182                 pkt->u.mode = mode;
 183                 break;
 184
 185         case VMCI_TRANSPORT_PACKET_TYPE_WAITING_READ:
 186         case VMCI_TRANSPORT_PACKET_TYPE_WAITING_WRITE:
 187                 memcpy(&pkt->u.wait, wait, sizeof(pkt->u.wait));
 188                 break;
 189
 190         case VMCI_TRANSPORT_PACKET_TYPE_REQUEST2:
 191         case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2:
 192                 pkt->u.size = size;
 193                 pkt->proto = proto;
 194                 break;
 195         }
 196 }
 197
 198 static inline void
 199 vmci_transport_packet_get_addresses(struct vmci_transport_packet *pkt,
 200                                     struct sockaddr_vm *local,
 201                                     struct sockaddr_vm *remote)
 202 {
 203         vsock_addr_init(local, pkt->dg.dst.context, pkt->dst_port);
 204         vsock_addr_init(remote, pkt->dg.src.context, pkt->src_port);
 205 }
 206
 207 static int
 208 __vmci_transport_send_control_pkt(struct vmci_transport_packet *pkt,
 209                                   struct sockaddr_vm *src,
 210                                   struct sockaddr_vm *dst,
 211                                   enum vmci_transport_packet_type type,
 212                                   u64 size,
 213                                   u64 mode,
 214                                   struct vmci_transport_waiting_info *wait,
 215                                   u16 proto,
 216                                   struct vmci_handle handle,
 217                                   bool convert_error)
 218 {
 219         int err;
 220
 221         vmci_transport_packet_init(pkt, src, dst, type, size, mode, wait,
 222                                    proto, handle);
 223         err = vmci_datagram_send(&pkt->dg);
 224         if (convert_error && (err < 0))
 225                 return vmci_transport_error_to_vsock_error(err);
 226
 227         return err;
 228 }
 229
 230 static int
 231 vmci_transport_reply_control_pkt_fast(struct vmci_transport_packet *pkt,
 232                                       enum vmci_transport_packet_type type,
 233                                       u64 size,
 234                                       u64 mode,
 235                                       struct vmci_transport_waiting_info *wait,
 236                                       struct vmci_handle handle)
 237 {
 238         struct vmci_transport_packet reply;
 239         struct sockaddr_vm src, dst;
 240
 241         if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST) {
 242                 return 0;
 243         } else {
 244                 vmci_transport_packet_get_addresses(pkt, &src, &dst);
 245                 return __vmci_transport_send_control_pkt(&reply, &src, &dst,
 246                                                          type,
 247                                                          size, mode, wait,
 248                                                          VSOCK_PROTO_INVALID,
 249                                                          handle, true);
 250         }
 251 }
 252
 253 static int
 254 vmci_transport_send_control_pkt_bh(struct sockaddr_vm *src,
 255                                    struct sockaddr_vm *dst,
 256                                    enum vmci_transport_packet_type type,
 257                                    u64 size,
 258                                    u64 mode,
 259                                    struct vmci_transport_waiting_info *wait,
 260                                    struct vmci_handle handle)
 261 {
 262         /* Note that it is safe to use a single packet across all CPUs since
 263          * two tasklets of the same type are guaranteed to not ever run
 264          * simultaneously. If that ever changes, or VMCI stops using tasklets,
 265          * we can use per-cpu packets.
 266          */
 267         static struct vmci_transport_packet pkt;
 268
 269         return __vmci_transport_send_control_pkt(&pkt, src, dst, type,
 270                                                  size, mode, wait,
 271                                                  VSOCK_PROTO_INVALID, handle,
 272                                                  false);
 273 }
 274
 275 static int
 276 vmci_transport_send_control_pkt(struct sock *sk,
 277                                 enum vmci_transport_packet_type type,
 278                                 u64 size,
 279                                 u64 mode,
 280                                 struct vmci_transport_waiting_info *wait,
 281                                 u16 proto,
 282                                 struct vmci_handle handle)
 283 {
 284         struct vmci_transport_packet *pkt;
 285         struct vsock_sock *vsk;
 286         int err;
 287
 288         vsk = vsock_sk(sk);
 289
 290         if (!vsock_addr_bound(&vsk->local_addr))
 291                 return -EINVAL;
 292
 293         if (!vsock_addr_bound(&vsk->remote_addr))
 294                 return -EINVAL;
 295
 296         pkt = kmalloc(sizeof(*pkt), GFP_KERNEL);
 297         if (!pkt)
 298                 return -ENOMEM;
 299
 300         err = __vmci_transport_send_control_pkt(pkt, &vsk->local_addr,
 301                                                 &vsk->remote_addr, type, size,
 302                                                 mode, wait, proto, handle,
 303                                                 true);
 304         kfree(pkt);
 305
 306         return err;
 307 }
 308
 309 static int vmci_transport_send_reset_bh(struct sockaddr_vm *dst,
 310                                         struct sockaddr_vm *src,
 311                                         struct vmci_transport_packet *pkt)
 312 {
 313         if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST)
 314                 return 0;
 315         return vmci_transport_send_control_pkt_bh(
 316                                         dst, src,
 317                                         VMCI_TRANSPORT_PACKET_TYPE_RST, 0,
 318                                         0, NULL, VMCI_INVALID_HANDLE);
 319 }
 320
 321 static int vmci_transport_send_reset(struct sock *sk,
 322                                      struct vmci_transport_packet *pkt)
 323 {
 324         if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST)
 325                 return 0;
 326         return vmci_transport_send_control_pkt(sk,
 327                                         VMCI_TRANSPORT_PACKET_TYPE_RST,
 328                                         0, 0, NULL, VSOCK_PROTO_INVALID,
 329                                         VMCI_INVALID_HANDLE);
 330 }
 331
 332 static int vmci_transport_send_negotiate(struct sock *sk, size_t size)
 333 {
 334         return vmci_transport_send_control_pkt(
 335                                         sk,
 336                                         VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE,
 337                                         size, 0, NULL,
 338                                         VSOCK_PROTO_INVALID,
 339                                         VMCI_INVALID_HANDLE);
 340 }
 341
 342 static int vmci_transport_send_negotiate2(struct sock *sk, size_t size,
 343                                           u16 version)
 344 {
 345         return vmci_transport_send_control_pkt(
 346                                         sk,
 347                                         VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2,
 348                                         size, 0, NULL, version,
 349                                         VMCI_INVALID_HANDLE);
 350 }
 351
 352 static int vmci_transport_send_qp_offer(struct sock *sk,
 353                                         struct vmci_handle handle)
 354 {
 355         return vmci_transport_send_control_pkt(
 356                                         sk, VMCI_TRANSPORT_PACKET_TYPE_OFFER, 0,
 357                                         0, NULL,
 358                                         VSOCK_PROTO_INVALID, handle);
 359 }
 360
 361 static int vmci_transport_send_attach(struct sock *sk,
 362                                       struct vmci_handle handle)
 363 {
 364         return vmci_transport_send_control_pkt(
 365                                         sk, VMCI_TRANSPORT_PACKET_TYPE_ATTACH,
 366                                         0, 0, NULL, VSOCK_PROTO_INVALID,
 367                                         handle);
 368 }
 369
 370 static int vmci_transport_reply_reset(struct vmci_transport_packet *pkt)
 371 {
 372         return vmci_transport_reply_control_pkt_fast(
 373                                                 pkt,
 374                                                 VMCI_TRANSPORT_PACKET_TYPE_RST,
 375                                                 0, 0, NULL,
 376                                                 VMCI_INVALID_HANDLE);
 377 }
 378
 379 static int vmci_transport_send_invalid_bh(struct sockaddr_vm *dst,
 380                                           struct sockaddr_vm *src)
 381 {
 382         return vmci_transport_send_control_pkt_bh(
 383                                         dst, src,
 384                                         VMCI_TRANSPORT_PACKET_TYPE_INVALID,
 385                                         0, 0, NULL, VMCI_INVALID_HANDLE);
 386 }
 387
 388 int vmci_transport_send_wrote_bh(struct sockaddr_vm *dst,
 389                                  struct sockaddr_vm *src)
 390 {
 391         return vmci_transport_send_control_pkt_bh(
 392                                         dst, src,
 393                                         VMCI_TRANSPORT_PACKET_TYPE_WROTE, 0,
 394                                         0, NULL, VMCI_INVALID_HANDLE);
 395 }
 396
 397 int vmci_transport_send_read_bh(struct sockaddr_vm *dst,
 398                                 struct sockaddr_vm *src)
 399 {
 400         return vmci_transport_send_control_pkt_bh(
 401                                         dst, src,
 402                                         VMCI_TRANSPORT_PACKET_TYPE_READ, 0,
 403                                         0, NULL, VMCI_INVALID_HANDLE);
 404 }
 405
 406 int vmci_transport_send_wrote(struct sock *sk)
 407 {
 408         return vmci_transport_send_control_pkt(
 409                                         sk, VMCI_TRANSPORT_PACKET_TYPE_WROTE, 0,
 410                                         0, NULL, VSOCK_PROTO_INVALID,
 411                                         VMCI_INVALID_HANDLE);
 412 }
 413
 414 int vmci_transport_send_read(struct sock *sk)
 415 {
 416         return vmci_transport_send_control_pkt(
 417                                         sk, VMCI_TRANSPORT_PACKET_TYPE_READ, 0,
 418                                         0, NULL, VSOCK_PROTO_INVALID,
 419                                         VMCI_INVALID_HANDLE);
 420 }
 421
 422 int vmci_transport_send_waiting_write(struct sock *sk,
 423                                       struct vmci_transport_waiting_info *wait)
 424 {
 425         return vmci_transport_send_control_pkt(
 426                                 sk, VMCI_TRANSPORT_PACKET_TYPE_WAITING_WRITE,
 427                                 0, 0, wait, VSOCK_PROTO_INVALID,
 428                                 VMCI_INVALID_HANDLE);
 429 }
 430
 431 int vmci_transport_send_waiting_read(struct sock *sk,
 432                                      struct vmci_transport_waiting_info *wait)
 433 {
 434         return vmci_transport_send_control_pkt(
 435                                 sk, VMCI_TRANSPORT_PACKET_TYPE_WAITING_READ,
 436                                 0, 0, wait, VSOCK_PROTO_INVALID,
 437                                 VMCI_INVALID_HANDLE);
 438 }
 439
 440 static int vmci_transport_shutdown(struct vsock_sock *vsk, int mode)
 441 {
 442         return vmci_transport_send_control_pkt(
 443                                         &vsk->sk,
 444                                         VMCI_TRANSPORT_PACKET_TYPE_SHUTDOWN,
 445                                         0, mode, NULL,
 446                                         VSOCK_PROTO_INVALID,
 447                                         VMCI_INVALID_HANDLE);
 448 }
 449
 450 static int vmci_transport_send_conn_request(struct sock *sk, size_t size)
 451 {
 452         return vmci_transport_send_control_pkt(sk,
 453                                         VMCI_TRANSPORT_PACKET_TYPE_REQUEST,
 454                                         size, 0, NULL,
 455                                         VSOCK_PROTO_INVALID,
 456                                         VMCI_INVALID_HANDLE);
 457 }
 458
 459 static int vmci_transport_send_conn_request2(struct sock *sk, size_t size,
 460                                              u16 version)
 461 {
 462         return vmci_transport_send_control_pkt(
 463                                         sk, VMCI_TRANSPORT_PACKET_TYPE_REQUEST2,
 464                                         size, 0, NULL, version,
 465                                         VMCI_INVALID_HANDLE);
 466 }
 467
 468 static struct sock *vmci_transport_get_pending(
 469                                         struct sock *listener,
 470                                         struct vmci_transport_packet *pkt)
 471 {
 472         struct vsock_sock *vlistener;
 473         struct vsock_sock *vpending;
 474         struct sock *pending;
 475         struct sockaddr_vm src;
 476
 477         vsock_addr_init(&src, pkt->dg.src.context, pkt->src_port);
 478
 479         vlistener = vsock_sk(listener);
 480
 481         list_for_each_entry(vpending, &vlistener->pending_links,
 482                             pending_links) {
 483                 if (vsock_addr_equals_addr(&src, &vpending->remote_addr) &&
 484                     pkt->dst_port == vpending->local_addr.svm_port) {
 485                         pending = sk_vsock(vpending);
 486                         sock_hold(pending);
 487                         goto found;
 488                 }
 489         }
 490
 491         pending = NULL;
 492 found:
 493         return pending;
 494
 495 }
 496
 497 static void vmci_transport_release_pending(struct sock *pending)
 498 {
 499         sock_put(pending);
 500 }
 501
 502 /* We allow two kinds of sockets to communicate with a restricted VM: 1)
 503  * trusted sockets 2) sockets from applications running as the same user as the
 504  * VM (this is only true for the host side and only when using hosted products)
 505  */
 506
 507 static bool vmci_transport_is_trusted(struct vsock_sock *vsock, u32 peer_cid)
 508 {
 509         return vsock->trusted ||
 510                vmci_is_context_owner(peer_cid, vsock->owner->uid);
 511 }
 512
 513 /* We allow sending datagrams to and receiving datagrams from a restricted VM
 514  * only if it is trusted as described in vmci_transport_is_trusted.
 515  */
 516
 517 static bool vmci_transport_allow_dgram(struct vsock_sock *vsock, u32 peer_cid)
 518 {
 519         if (VMADDR_CID_HYPERVISOR == peer_cid)
 520                 return true;
 521
 522         if (vsock->cached_peer != peer_cid) {
 523                 vsock->cached_peer = peer_cid;
 524                 if (!vmci_transport_is_trusted(vsock, peer_cid) &&
 525                     (vmci_context_get_priv_flags(peer_cid) &
 526                      VMCI_PRIVILEGE_FLAG_RESTRICTED)) {
 527                         vsock->cached_peer_allow_dgram = false;
 528                 } else {
 529                         vsock->cached_peer_allow_dgram = true;
 530                 }
 531         }
 532
 533         return vsock->cached_peer_allow_dgram;
 534 }
 535
 536 static int
 537 vmci_transport_queue_pair_alloc(struct vmci_qp **qpair,
 538                                 struct vmci_handle *handle,
 539                                 u64 produce_size,
 540                                 u64 consume_size,
 541                                 u32 peer, u32 flags, bool trusted)
 542 {
 543         int err = 0;
 544
 545         if (trusted) {
 546                 /* Try to allocate our queue pair as trusted. This will only
 547                  * work if vsock is running in the host.
 548                  */
 549
 550                 err = vmci_qpair_alloc(qpair, handle, produce_size,
 551                                        consume_size,
 552                                        peer, flags,
 553                                        VMCI_PRIVILEGE_FLAG_TRUSTED);
 554                 if (err != VMCI_ERROR_NO_ACCESS)
 555                         goto out;
 556
 557         }
 558
 559         err = vmci_qpair_alloc(qpair, handle, produce_size, consume_size,
 560                                peer, flags, VMCI_NO_PRIVILEGE_FLAGS);
 561 out:
 562         if (err < 0) {
 563                 pr_err("Could not attach to queue pair with %d\n",
 564                        err);
 565                 err = vmci_transport_error_to_vsock_error(err);
 566         }
 567
 568         return err;
 569 }
 570
 571 static int
 572 vmci_transport_datagram_create_hnd(u32 resource_id,
 573                                    u32 flags,
 574                                    vmci_datagram_recv_cb recv_cb,
 575                                    void *client_data,
 576                                    struct vmci_handle *out_handle)
 577 {
 578         int err = 0;
 579
 580         /* Try to allocate our datagram handler as trusted. This will only work
 581          * if vsock is running in the host.
 582          */
 583
 584         err = vmci_datagram_create_handle_priv(resource_id, flags,
 585                                                VMCI_PRIVILEGE_FLAG_TRUSTED,
 586                                                recv_cb,
 587                                                client_data, out_handle);
 588
 589         if (err == VMCI_ERROR_NO_ACCESS)
 590                 err = vmci_datagram_create_handle(resource_id, flags,
 591                                                   recv_cb, client_data,
 592                                                   out_handle);
 593
 594         return err;
 595 }
 596
 597 /* This is invoked as part of a tasklet that's scheduled when the VMCI
 598  * interrupt fires.  This is run in bottom-half context and if it ever needs to
 599  * sleep it should defer that work to a work queue.
 600  */
 601
 602 static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg)
 603 {
 604         struct sock *sk;
 605         size_t size;
 606         struct sk_buff *skb;
 607         struct vsock_sock *vsk;
 608
 609         sk = (struct sock *)data;
 610
 611         /* This handler is privileged when this module is running on the host.
 612          * We will get datagrams from all endpoints (even VMs that are in a
 613          * restricted context). If we get one from a restricted context then
 614          * the destination socket must be trusted.
 615          *
 616          * NOTE: We access the socket struct without holding the lock here.
 617          * This is ok because the field we are interested is never modified
 618          * outside of the create and destruct socket functions.
 619          */
 620         vsk = vsock_sk(sk);
 621         if (!vmci_transport_allow_dgram(vsk, dg->src.context))
 622                 return VMCI_ERROR_NO_ACCESS;
 623
 624         size = VMCI_DG_SIZE(dg);
 625
 626         /* Attach the packet to the socket's receive queue as an sk_buff. */
 627         skb = alloc_skb(size, GFP_ATOMIC);
 628         if (!skb)
 629                 return VMCI_ERROR_NO_MEM;
 630
 631         /* sk_receive_skb() will do a sock_put(), so hold here. */
 632         sock_hold(sk);
 633         skb_put(skb, size);
 634         memcpy(skb->data, dg, size);
 635         sk_receive_skb(sk, skb, 0);
 636
 637         return VMCI_SUCCESS;
 638 }
 639
 640 static bool vmci_transport_stream_allow(u32 cid, u32 port)
 641 {
 642         static const u32 non_socket_contexts[] = {
 643                 VMADDR_CID_RESERVED,
 644         };
 645         int i;
 646
 647         BUILD_BUG_ON(sizeof(cid) != sizeof(*non_socket_contexts));
 648
 649         for (i = 0; i < ARRAY_SIZE(non_socket_contexts); i++) {
 650                 if (cid == non_socket_contexts[i])
 651                         return false;
 652         }
 653
 654         return true;
 655 }
 656
 657 /* This is invoked as part of a tasklet that's scheduled when the VMCI
 658  * interrupt fires.  This is run in bottom-half context but it defers most of
 659  * its work to the packet handling work queue.
 660  */
 661
 662 static int vmci_transport_recv_stream_cb(void *data, struct vmci_datagram *dg)
 663 {
 664         struct sock *sk;
 665         struct sockaddr_vm dst;
 666         struct sockaddr_vm src;
 667         struct vmci_transport_packet *pkt;
 668         struct vsock_sock *vsk;
 669         bool bh_process_pkt;
 670         int err;
 671
 672         sk = NULL;
 673         err = VMCI_SUCCESS;
 674         bh_process_pkt = false;
 675
 676         /* Ignore incoming packets from contexts without sockets, or resources
 677          * that aren't vsock implementations.
 678          */
 679
 680         if (!vmci_transport_stream_allow(dg->src.context, -1)
 681             || vmci_transport_peer_rid(dg->src.context) != dg->src.resource)
 682                 return VMCI_ERROR_NO_ACCESS;
 683
 684         if (VMCI_DG_SIZE(dg) < sizeof(*pkt))
 685                 /* Drop datagrams that do not contain full VSock packets. */
 686                 return VMCI_ERROR_INVALID_ARGS;
 687
 688         pkt = (struct vmci_transport_packet *)dg;
 689
 690         /* Find the socket that should handle this packet.  First we look for a
 691          * connected socket and if there is none we look for a socket bound to
 692          * the destintation address.
 693          */
 694         vsock_addr_init(&src, pkt->dg.src.context, pkt->src_port);
 695         vsock_addr_init(&dst, pkt->dg.dst.context, pkt->dst_port);
 696
 697         sk = vsock_find_connected_socket(&src, &dst);
 698         if (!sk) {
 699                 sk = vsock_find_bound_socket(&dst);
 700                 if (!sk) {
 701                         /* We could not find a socket for this specified
 702                          * address.  If this packet is a RST, we just drop it.
 703                          * If it is another packet, we send a RST.  Note that
 704                          * we do not send a RST reply to RSTs so that we do not
 705                          * continually send RSTs between two endpoints.
 706                          *
 707                          * Note that since this is a reply, dst is src and src
 708                          * is dst.
 709                          */
 710                         if (vmci_transport_send_reset_bh(&dst, &src, pkt) < 0)
 711                                 pr_err("unable to send reset\n");
 712
 713                         err = VMCI_ERROR_NOT_FOUND;
 714                         goto out;
 715                 }
 716         }
 717
 718         /* If the received packet type is beyond all types known to this
 719          * implementation, reply with an invalid message.  Hopefully this will
 720          * help when implementing backwards compatibility in the future.
 721          */
 722         if (pkt->type >= VMCI_TRANSPORT_PACKET_TYPE_MAX) {
 723                 vmci_transport_send_invalid_bh(&dst, &src);
 724                 err = VMCI_ERROR_INVALID_ARGS;
 725                 goto out;
 726         }
 727
 728         /* This handler is privileged when this module is running on the host.
 729          * We will get datagram connect requests from all endpoints (even VMs
 730          * that are in a restricted context). If we get one from a restricted
 731          * context then the destination socket must be trusted.
 732          *
 733          * NOTE: We access the socket struct without holding the lock here.
 734          * This is ok because the field we are interested is never modified
 735          * outside of the create and destruct socket functions.
 736          */
 737         vsk = vsock_sk(sk);
 738         if (!vmci_transport_allow_dgram(vsk, pkt->dg.src.context)) {
 739                 err = VMCI_ERROR_NO_ACCESS;
 740                 goto out;
 741         }
 742
 743         /* We do most everything in a work queue, but let's fast path the
 744          * notification of reads and writes to help data transfer performance.
 745          * We can only do this if there is no process context code executing
 746          * for this socket since that may change the state.
 747          */
 748         bh_lock_sock(sk);
 749
 750         if (!sock_owned_by_user(sk)) {
 751                 /* The local context ID may be out of date, update it. */
 752                 vsk->local_addr.svm_cid = dst.svm_cid;
 753
 754                 if (sk->sk_state == SS_CONNECTED)
 755                         vmci_trans(vsk)->notify_ops->handle_notify_pkt(
 756                                         sk, pkt, true, &dst, &src,
 757                                         &bh_process_pkt);
 758         }
 759
 760         bh_unlock_sock(sk);
 761
 762         if (!bh_process_pkt) {
 763                 struct vmci_transport_recv_pkt_info *recv_pkt_info;
 764
 765                 recv_pkt_info = kmalloc(sizeof(*recv_pkt_info), GFP_ATOMIC);
 766                 if (!recv_pkt_info) {
 767                         if (vmci_transport_send_reset_bh(&dst, &src, pkt) < 0)
 768                                 pr_err("unable to send reset\n");
 769
 770                         err = VMCI_ERROR_NO_MEM;
 771                         goto out;
 772                 }
 773
 774                 recv_pkt_info->sk = sk;
 775                 memcpy(&recv_pkt_info->pkt, pkt, sizeof(recv_pkt_info->pkt));
 776                 INIT_WORK(&recv_pkt_info->work, vmci_transport_recv_pkt_work);
 777
 778                 schedule_work(&recv_pkt_info->work);
 779                 /* Clear sk so that the reference count incremented by one of
 780                  * the Find functions above is not decremented below.  We need
 781                  * that reference count for the packet handler we've scheduled
 782                  * to run.
 783                  */
 784                 sk = NULL;
 785         }
 786
 787 out:
 788         if (sk)
 789                 sock_put(sk);
 790
 791         return err;
 792 }
 793
 794 static void vmci_transport_peer_attach_cb(u32 sub_id,
 795                                           const struct vmci_event_data *e_data,
 796                                           void *client_data)
 797 {
 798         struct sock *sk = client_data;
 799         const struct vmci_event_payload_qp *e_payload;
 800         struct vsock_sock *vsk;
 801
 802         e_payload = vmci_event_data_const_payload(e_data);
 803
 804         vsk = vsock_sk(sk);
 805
 806         /* We don't ask for delayed CBs when we subscribe to this event (we
 807          * pass 0 as flags to vmci_event_subscribe()).  VMCI makes no
 808          * guarantees in that case about what context we might be running in,
 809          * so it could be BH or process, blockable or non-blockable.  So we
 810          * need to account for all possible contexts here.
 811          */
 812         local_bh_disable();
 813         bh_lock_sock(sk);
 814
 815         /* XXX This is lame, we should provide a way to lookup sockets by
 816          * qp_handle.
 817          */
 818         if (vmci_handle_is_equal(vmci_trans(vsk)->qp_handle,
 819                                  e_payload->handle)) {
 820                 /* XXX This doesn't do anything, but in the future we may want
 821                  * to set a flag here to verify the attach really did occur and
 822                  * we weren't just sent a datagram claiming it was.
 823                  */
 824                 goto out;
 825         }
 826
 827 out:
 828         bh_unlock_sock(sk);
 829         local_bh_enable();
 830 }
 831
 832 static void vmci_transport_handle_detach(struct sock *sk)
 833 {
 834         struct vsock_sock *vsk;
 835
 836         vsk = vsock_sk(sk);
 837         if (!vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle)) {
 838                 sock_set_flag(sk, SOCK_DONE);
 839
 840                 /* On a detach the peer will not be sending or receiving
 841                  * anymore.
 842                  */
 843                 vsk->peer_shutdown = SHUTDOWN_MASK;
 844
 845                 /* We should not be sending anymore since the peer won't be
 846                  * there to receive, but we can still receive if there is data
 847                  * left in our consume queue.
 848                  */
 849                 if (vsock_stream_has_data(vsk) <= 0) {
 850                         if (sk->sk_state == SS_CONNECTING) {
 851                                 /* The peer may detach from a queue pair while
 852                                  * we are still in the connecting state, i.e.,
 853                                  * if the peer VM is killed after attaching to
 854                                  * a queue pair, but before we complete the
 855                                  * handshake. In that case, we treat the detach
 856                                  * event like a reset.
 857                                  */
 858
 859                                 sk->sk_state = SS_UNCONNECTED;
 860                                 sk->sk_err = ECONNRESET;
 861                                 sk->sk_error_report(sk);
 862                                 return;
 863                         }
 864                         sk->sk_state = SS_UNCONNECTED;
 865                 }
 866                 sk->sk_state_change(sk);
 867         }
 868 }
 869
 870 static void vmci_transport_peer_detach_cb(u32 sub_id,
 871                                           const struct vmci_event_data *e_data,
 872                                           void *client_data)
 873 {
 874         struct sock *sk = client_data;
 875         const struct vmci_event_payload_qp *e_payload;
 876         struct vsock_sock *vsk;
 877
 878         e_payload = vmci_event_data_const_payload(e_data);
 879         vsk = vsock_sk(sk);
 880         if (vmci_handle_is_invalid(e_payload->handle))
 881                 return;
 882
 883         /* Same rules for locking as for peer_attach_cb(). */
 884         local_bh_disable();
 885         bh_lock_sock(sk);
 886
 887         /* XXX This is lame, we should provide a way to lookup sockets by
 888          * qp_handle.
 889          */
 890         if (vmci_handle_is_equal(vmci_trans(vsk)->qp_handle,
 891                                  e_payload->handle))
 892                 vmci_transport_handle_detach(sk);
 893
 894         bh_unlock_sock(sk);
 895         local_bh_enable();
 896 }
 897
 898 static void vmci_transport_qp_resumed_cb(u32 sub_id,
 899                                          const struct vmci_event_data *e_data,
 900                                          void *client_data)
 901 {
 902         vsock_for_each_connected_socket(vmci_transport_handle_detach);
 903 }
 904
 905 static void vmci_transport_recv_pkt_work(struct work_struct *work)
 906 {
 907         struct vmci_transport_recv_pkt_info *recv_pkt_info;
 908         struct vmci_transport_packet *pkt;
 909         struct sock *sk;
 910
 911         recv_pkt_info =
 912                 container_of(work, struct vmci_transport_recv_pkt_info, work);
 913         sk = recv_pkt_info->sk;
 914         pkt = &recv_pkt_info->pkt;
 915
 916         lock_sock(sk);
 917
 918         /* The local context ID may be out of date. */
 919         vsock_sk(sk)->local_addr.svm_cid = pkt->dg.dst.context;
 920
 921         switch (sk->sk_state) {
 922         case SS_LISTEN:
 923                 vmci_transport_recv_listen(sk, pkt);
 924                 break;
 925         case SS_CONNECTING:
 926                 /* Processing of pending connections for servers goes through
 927                  * the listening socket, so see vmci_transport_recv_listen()
 928                  * for that path.
 929                  */
 930                 vmci_transport_recv_connecting_client(sk, pkt);
 931                 break;
 932         case SS_CONNECTED:
 933                 vmci_transport_recv_connected(sk, pkt);
 934                 break;
 935         default:
 936                 /* Because this function does not run in the same context as
 937                  * vmci_transport_recv_stream_cb it is possible that the
 938                  * socket has closed. We need to let the other side know or it
 939                  * could be sitting in a connect and hang forever. Send a
 940                  * reset to prevent that.
 941                  */
 942                 vmci_transport_send_reset(sk, pkt);
 943                 break;
 944         }
 945
 946         release_sock(sk);
 947         kfree(recv_pkt_info);
 948         /* Release reference obtained in the stream callback when we fetched
 949          * this socket out of the bound or connected list.
 950          */
 951         sock_put(sk);
 952 }
 953
 954 static int vmci_transport_recv_listen(struct sock *sk,
 955                                       struct vmci_transport_packet *pkt)
 956 {
 957         struct sock *pending;
 958         struct vsock_sock *vpending;
 959         int err;
 960         u64 qp_size;
 961         bool old_request = false;
 962         bool old_pkt_proto = false;
 963
 964         err = 0;
 965
 966         /* Because we are in the listen state, we could be receiving a packet
 967          * for ourself or any previous connection requests that we received.
 968          * If it's the latter, we try to find a socket in our list of pending
 969          * connections and, if we do, call the appropriate handler for the
 970          * state that that socket is in.  Otherwise we try to service the
 971          * connection request.
 972          */
 973         pending = vmci_transport_get_pending(sk, pkt);
 974         if (pending) {
 975                 lock_sock(pending);
 976
 977                 /* The local context ID may be out of date. */
 978                 vsock_sk(pending)->local_addr.svm_cid = pkt->dg.dst.context;
 979
 980                 switch (pending->sk_state) {
 981                 case SS_CONNECTING:
 982                         err = vmci_transport_recv_connecting_server(sk,
 983                                                                     pending,
 984                                                                     pkt);
 985                         break;
 986                 default:
 987                         vmci_transport_send_reset(pending, pkt);
 988                         err = -EINVAL;
 989                 }
 990
 991                 if (err < 0)
 992                         vsock_remove_pending(sk, pending);
 993
 994                 release_sock(pending);
 995                 vmci_transport_release_pending(pending);
 996
 997                 return err;
 998         }
 999
1000         /* The listen state only accepts connection requests.  Reply with a
1001          * reset unless we received a reset.
1002          */
1003
1004         if (!(pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST ||
1005               pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST2)) {
1006                 vmci_transport_reply_reset(pkt);
1007                 return -EINVAL;
1008         }
1009
1010         if (pkt->u.size == 0) {
1011                 vmci_transport_reply_reset(pkt);
1012                 return -EINVAL;
1013         }
1014
1015         /* If this socket can't accommodate this connection request, we send a
1016          * reset.  Otherwise we create and initialize a child socket and reply
1017          * with a connection negotiation.
1018          */
1019         if (sk->sk_ack_backlog >= sk->sk_max_ack_backlog) {
1020                 vmci_transport_reply_reset(pkt);
1021                 return -ECONNREFUSED;
1022         }
1023
1024         pending = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
1025                                  sk->sk_type, 0);
1026         if (!pending) {
1027                 vmci_transport_send_reset(sk, pkt);
1028                 return -ENOMEM;
1029         }
1030
1031         vpending = vsock_sk(pending);
1032
1033         vsock_addr_init(&vpending->local_addr, pkt->dg.dst.context,
1034                         pkt->dst_port);
1035         vsock_addr_init(&vpending->remote_addr, pkt->dg.src.context,
1036                         pkt->src_port);
1037
1038         /* If the proposed size fits within our min/max, accept it. Otherwise
1039          * propose our own size.
1040          */
1041         if (pkt->u.size >= vmci_trans(vpending)->queue_pair_min_size &&
1042             pkt->u.size <= vmci_trans(vpending)->queue_pair_max_size) {
1043                 qp_size = pkt->u.size;
1044         } else {
1045                 qp_size = vmci_trans(vpending)->queue_pair_size;
1046         }
1047
1048         /* Figure out if we are using old or new requests based on the
1049          * overrides pkt types sent by our peer.
1050          */
1051         if (vmci_transport_old_proto_override(&old_pkt_proto)) {
1052                 old_request = old_pkt_proto;
1053         } else {
1054                 if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST)
1055                         old_request = true;
1056                 else if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST2)
1057                         old_request = false;
1058
1059         }
1060
1061         if (old_request) {
1062                 /* Handle a REQUEST (or override) */
1063                 u16 version = VSOCK_PROTO_INVALID;
1064                 if (vmci_transport_proto_to_notify_struct(
1065                         pending, &version, true))
1066                         err = vmci_transport_send_negotiate(pending, qp_size);
1067                 else
1068                         err = -EINVAL;
1069
1070         } else {
1071                 /* Handle a REQUEST2 (or override) */
1072                 int proto_int = pkt->proto;
1073                 int pos;
1074                 u16 active_proto_version = 0;
1075
1076                 /* The list of possible protocols is the intersection of all
1077                  * protocols the client supports ... plus all the protocols we
1078                  * support.
1079                  */
1080                 proto_int &= vmci_transport_new_proto_supported_versions();
1081
1082                 /* We choose the highest possible protocol version and use that
1083                  * one.
1084                  */
1085                 pos = fls(proto_int);
1086                 if (pos) {
1087                         active_proto_version = (1 << (pos - 1));
1088                         if (vmci_transport_proto_to_notify_struct(
1089                                 pending, &active_proto_version, false))
1090                                 err = vmci_transport_send_negotiate2(pending,
1091                                                         qp_size,
1092                                                         active_proto_version);
1093                         else
1094                                 err = -EINVAL;
1095
1096                 } else {
1097                         err = -EINVAL;
1098                 }
1099         }
1100
1101         if (err < 0) {
1102                 vmci_transport_send_reset(sk, pkt);
1103                 sock_put(pending);
1104                 err = vmci_transport_error_to_vsock_error(err);
1105                 goto out;
1106         }
1107
1108         vsock_add_pending(sk, pending);
1109         sk->sk_ack_backlog++;
1110
1111         pending->sk_state = SS_CONNECTING;
1112         vmci_trans(vpending)->produce_size =
1113                 vmci_trans(vpending)->consume_size = qp_size;
1114         vmci_trans(vpending)->queue_pair_size = qp_size;
1115
1116         vmci_trans(vpending)->notify_ops->process_request(pending);
1117
1118         /* We might never receive another message for this socket and it's not
1119          * connected to any process, so we have to ensure it gets cleaned up
1120          * ourself.  Our delayed work function will take care of that.  Note
1121          * that we do not ever cancel this function since we have few
1122          * guarantees about its state when calling cancel_delayed_work().
1123          * Instead we hold a reference on the socket for that function and make
1124          * it capable of handling cases where it needs to do nothing but
1125          * release that reference.
1126          */
1127         vpending->listener = sk;
1128         sock_hold(sk);
1129         sock_hold(pending);
1130         INIT_DELAYED_WORK(&vpending->dwork, vsock_pending_work);
1131         schedule_delayed_work(&vpending->dwork, HZ);
1132
1133 out:
1134         return err;
1135 }
1136
1137 static int
1138 vmci_transport_recv_connecting_server(struct sock *listener,
1139                                       struct sock *pending,
1140                                       struct vmci_transport_packet *pkt)
1141 {
1142         struct vsock_sock *vpending;
1143         struct vmci_handle handle;
1144         struct vmci_qp *qpair;
1145         bool is_local;
1146         u32 flags;
1147         u32 detach_sub_id;
1148         int err;
1149         int skerr;
1150
1151         vpending = vsock_sk(pending);
1152         detach_sub_id = VMCI_INVALID_ID;
1153
1154         switch (pkt->type) {
1155         case VMCI_TRANSPORT_PACKET_TYPE_OFFER:
1156                 if (vmci_handle_is_invalid(pkt->u.handle)) {
1157                         vmci_transport_send_reset(pending, pkt);
1158                         skerr = EPROTO;
1159                         err = -EINVAL;
1160                         goto destroy;
1161                 }
1162                 break;
1163         default:
1164                 /* Close and cleanup the connection. */
1165                 vmci_transport_send_reset(pending, pkt);
1166                 skerr = EPROTO;
1167                 err = pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST ? 0 : -EINVAL;
1168                 goto destroy;
1169         }
1170
1171         /* In order to complete the connection we need to attach to the offered
1172          * queue pair and send an attach notification.  We also subscribe to the
1173          * detach event so we know when our peer goes away, and we do that
1174          * before attaching so we don't miss an event.  If all this succeeds,
1175          * we update our state and wakeup anything waiting in accept() for a
1176          * connection.
1177          */
1178
1179         /* We don't care about attach since we ensure the other side has
1180          * attached by specifying the ATTACH_ONLY flag below.
1181          */
1182         err = vmci_event_subscribe(VMCI_EVENT_QP_PEER_DETACH,
1183                                    vmci_transport_peer_detach_cb,
1184                                    pending, &detach_sub_id);
1185         if (err < VMCI_SUCCESS) {
1186                 vmci_transport_send_reset(pending, pkt);
1187                 err = vmci_transport_error_to_vsock_error(err);
1188                 skerr = -err;
1189                 goto destroy;
1190         }
1191
1192         vmci_trans(vpending)->detach_sub_id = detach_sub_id;
1193
1194         /* Now attach to the queue pair the client created. */
1195         handle = pkt->u.handle;
1196
1197         /* vpending->local_addr always has a context id so we do not need to
1198          * worry about VMADDR_CID_ANY in this case.
1199          */
1200         is_local =
1201             vpending->remote_addr.svm_cid == vpending->local_addr.svm_cid;
1202         flags = VMCI_QPFLAG_ATTACH_ONLY;
1203         flags |= is_local ? VMCI_QPFLAG_LOCAL : 0;
1204
1205         err = vmci_transport_queue_pair_alloc(
1206                                         &qpair,
1207                                         &handle,
1208                                         vmci_trans(vpending)->produce_size,
1209                                         vmci_trans(vpending)->consume_size,
1210                                         pkt->dg.src.context,
1211                                         flags,
1212                                         vmci_transport_is_trusted(
1213                                                 vpending,
1214                                                 vpending->remote_addr.svm_cid));
1215         if (err < 0) {
1216                 vmci_transport_send_reset(pending, pkt);
1217                 skerr = -err;
1218                 goto destroy;
1219         }
1220
1221         vmci_trans(vpending)->qp_handle = handle;
1222         vmci_trans(vpending)->qpair = qpair;
1223
1224         /* When we send the attach message, we must be ready to handle incoming
1225          * control messages on the newly connected socket. So we move the
1226          * pending socket to the connected state before sending the attach
1227          * message. Otherwise, an incoming packet triggered by the attach being
1228          * received by the peer may be processed concurrently with what happens
1229          * below after sending the attach message, and that incoming packet
1230          * will find the listening socket instead of the (currently) pending
1231          * socket. Note that enqueueing the socket increments the reference
1232          * count, so even if a reset comes before the connection is accepted,
1233          * the socket will be valid until it is removed from the queue.
1234          *
1235          * If we fail sending the attach below, we remove the socket from the
1236          * connected list and move the socket to SS_UNCONNECTED before
1237          * releasing the lock, so a pending slow path processing of an incoming
1238          * packet will not see the socket in the connected state in that case.
1239          */
1240         pending->sk_state = SS_CONNECTED;
1241
1242         vsock_insert_connected(vpending);
1243
1244         /* Notify our peer of our attach. */
1245         err = vmci_transport_send_attach(pending, handle);
1246         if (err < 0) {
1247                 vsock_remove_connected(vpending);
1248                 pr_err("Could not send attach\n");
1249                 vmci_transport_send_reset(pending, pkt);
1250                 err = vmci_transport_error_to_vsock_error(err);
1251                 skerr = -err;
1252                 goto destroy;
1253         }
1254
1255         /* We have a connection. Move the now connected socket from the
1256          * listener's pending list to the accept queue so callers of accept()
1257          * can find it.
1258          */
1259         vsock_remove_pending(listener, pending);
1260         vsock_enqueue_accept(listener, pending);
1261
1262         /* Callers of accept() will be be waiting on the listening socket, not
1263          * the pending socket.
1264          */
1265         listener->sk_state_change(listener);
1266
1267         return 0;
1268
1269 destroy:
1270         pending->sk_err = skerr;
1271         pending->sk_state = SS_UNCONNECTED;
1272         /* As long as we drop our reference, all necessary cleanup will handle
1273          * when the cleanup function drops its reference and our destruct
1274          * implementation is called.  Note that since the listen handler will
1275          * remove pending from the pending list upon our failure, the cleanup
1276          * function won't drop the additional reference, which is why we do it
1277          * here.
1278          */
1279         sock_put(pending);
1280
1281         return err;
1282 }
1283
1284 static int
1285 vmci_transport_recv_connecting_client(struct sock *sk,
1286                                       struct vmci_transport_packet *pkt)
1287 {
1288         struct vsock_sock *vsk;
1289         int err;
1290         int skerr;
1291
1292         vsk = vsock_sk(sk);
1293
1294         switch (pkt->type) {
1295         case VMCI_TRANSPORT_PACKET_TYPE_ATTACH:
1296                 if (vmci_handle_is_invalid(pkt->u.handle) ||
1297                     !vmci_handle_is_equal(pkt->u.handle,
1298                                           vmci_trans(vsk)->qp_handle)) {
1299                         skerr = EPROTO;
1300                         err = -EINVAL;
1301                         goto destroy;
1302                 }
1303
1304                 /* Signify the socket is connected and wakeup the waiter in
1305                  * connect(). Also place the socket in the connected table for
1306                  * accounting (it can already be found since it's in the bound
1307                  * table).
1308                  */
1309                 sk->sk_state = SS_CONNECTED;
1310                 sk->sk_socket->state = SS_CONNECTED;
1311                 vsock_insert_connected(vsk);
1312                 sk->sk_state_change(sk);
1313
1314                 break;
1315         case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE:
1316         case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2:
1317                 if (pkt->u.size == 0
1318                     || pkt->dg.src.context != vsk->remote_addr.svm_cid
1319                     || pkt->src_port != vsk->remote_addr.svm_port
1320                     || !vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle)
1321                     || vmci_trans(vsk)->qpair
1322                     || vmci_trans(vsk)->produce_size != 0
1323                     || vmci_trans(vsk)->consume_size != 0
1324                     || vmci_trans(vsk)->attach_sub_id != VMCI_INVALID_ID
1325                     || vmci_trans(vsk)->detach_sub_id != VMCI_INVALID_ID) {
1326                         skerr = EPROTO;
1327                         err = -EINVAL;
1328
1329                         goto destroy;
1330                 }
1331
1332                 err = vmci_transport_recv_connecting_client_negotiate(sk, pkt);
1333                 if (err) {
1334                         skerr = -err;
1335                         goto destroy;
1336                 }
1337
1338                 break;
1339         case VMCI_TRANSPORT_PACKET_TYPE_INVALID:
1340                 err = vmci_transport_recv_connecting_client_invalid(sk, pkt);
1341                 if (err) {
1342                         skerr = -err;
1343                         goto destroy;
1344                 }
1345
1346                 break;
1347         case VMCI_TRANSPORT_PACKET_TYPE_RST:
1348                 /* Older versions of the linux code (WS 6.5 / ESX 4.0) used to
1349                  * continue processing here after they sent an INVALID packet.
1350                  * This meant that we got a RST after the INVALID. We ignore a
1351                  * RST after an INVALID. The common code doesn't send the RST
1352                  * ... so we can hang if an old version of the common code
1353                  * fails between getting a REQUEST and sending an OFFER back.
1354                  * Not much we can do about it... except hope that it doesn't
1355                  * happen.
1356                  */
1357                 if (vsk->ignore_connecting_rst) {
1358                         vsk->ignore_connecting_rst = false;
1359                 } else {
1360                         skerr = ECONNRESET;
1361                         err = 0;
1362                         goto destroy;
1363                 }
1364
1365                 break;
1366         default:
1367                 /* Close and cleanup the connection. */
1368                 skerr = EPROTO;
1369                 err = -EINVAL;
1370                 goto destroy;
1371         }
1372
1373         return 0;
1374
1375 destroy:
1376         vmci_transport_send_reset(sk, pkt);
1377
1378         sk->sk_state = SS_UNCONNECTED;
1379         sk->sk_err = skerr;
1380         sk->sk_error_report(sk);
1381         return err;
1382 }
1383
1384 static int vmci_transport_recv_connecting_client_negotiate(
1385                                         struct sock *sk,
1386                                         struct vmci_transport_packet *pkt)
1387 {
1388         int err;
1389         struct vsock_sock *vsk;
1390         struct vmci_handle handle;
1391         struct vmci_qp *qpair;
1392         u32 attach_sub_id;
1393         u32 detach_sub_id;
1394         bool is_local;
1395         u32 flags;
1396         bool old_proto = true;
1397         bool old_pkt_proto;
1398         u16 version;
1399
1400         vsk = vsock_sk(sk);
1401         handle = VMCI_INVALID_HANDLE;
1402         attach_sub_id = VMCI_INVALID_ID;
1403         detach_sub_id = VMCI_INVALID_ID;
1404
1405         /* If we have gotten here then we should be past the point where old
1406          * linux vsock could have sent the bogus rst.
1407          */
1408         vsk->sent_request = false;
1409         vsk->ignore_connecting_rst = false;
1410
1411         /* Verify that we're OK with the proposed queue pair size */
1412         if (pkt->u.size < vmci_trans(vsk)->queue_pair_min_size ||
1413             pkt->u.size > vmci_trans(vsk)->queue_pair_max_size) {
1414                 err = -EINVAL;
1415                 goto destroy;
1416         }
1417
1418         /* At this point we know the CID the peer is using to talk to us. */
1419
1420         if (vsk->local_addr.svm_cid == VMADDR_CID_ANY)
1421                 vsk->local_addr.svm_cid = pkt->dg.dst.context;
1422
1423         /* Setup the notify ops to be the highest supported version that both
1424          * the server and the client support.
1425          */
1426
1427         if (vmci_transport_old_proto_override(&old_pkt_proto)) {
1428                 old_proto = old_pkt_proto;
1429         } else {
1430                 if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE)
1431                         old_proto = true;
1432                 else if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2)
1433                         old_proto = false;
1434
1435         }
1436
1437         if (old_proto)
1438                 version = VSOCK_PROTO_INVALID;
1439         else
1440                 version = pkt->proto;
1441
1442         if (!vmci_transport_proto_to_notify_struct(sk, &version, old_proto)) {
1443                 err = -EINVAL;
1444                 goto destroy;
1445         }
1446
1447         /* Subscribe to attach and detach events first.
1448          *
1449          * XXX We attach once for each queue pair created for now so it is easy
1450          * to find the socket (it's provided), but later we should only
1451          * subscribe once and add a way to lookup sockets by queue pair handle.
1452          */
1453         err = vmci_event_subscribe(VMCI_EVENT_QP_PEER_ATTACH,
1454                                    vmci_transport_peer_attach_cb,
1455                                    sk, &attach_sub_id);
1456         if (err < VMCI_SUCCESS) {
1457                 err = vmci_transport_error_to_vsock_error(err);
1458                 goto destroy;
1459         }
1460
1461         err = vmci_event_subscribe(VMCI_EVENT_QP_PEER_DETACH,
1462                                    vmci_transport_peer_detach_cb,
1463                                    sk, &detach_sub_id);
1464         if (err < VMCI_SUCCESS) {
1465                 err = vmci_transport_error_to_vsock_error(err);
1466                 goto destroy;
1467         }
1468
1469         /* Make VMCI select the handle for us. */
1470         handle = VMCI_INVALID_HANDLE;
1471         is_local = vsk->remote_addr.svm_cid == vsk->local_addr.svm_cid;
1472         flags = is_local ? VMCI_QPFLAG_LOCAL : 0;
1473
1474         err = vmci_transport_queue_pair_alloc(&qpair,
1475                                               &handle,
1476                                               pkt->u.size,
1477                                               pkt->u.size,
1478                                               vsk->remote_addr.svm_cid,
1479                                               flags,
1480                                               vmci_transport_is_trusted(
1481                                                   vsk,
1482                                                   vsk->
1483                                                   remote_addr.svm_cid));
1484         if (err < 0)
1485                 goto destroy;
1486
1487         err = vmci_transport_send_qp_offer(sk, handle);
1488         if (err < 0) {
1489                 err = vmci_transport_error_to_vsock_error(err);
1490                 goto destroy;
1491         }
1492
1493         vmci_trans(vsk)->qp_handle = handle;
1494         vmci_trans(vsk)->qpair = qpair;
1495
1496         vmci_trans(vsk)->produce_size = vmci_trans(vsk)->consume_size =
1497                 pkt->u.size;
1498
1499         vmci_trans(vsk)->attach_sub_id = attach_sub_id;
1500         vmci_trans(vsk)->detach_sub_id = detach_sub_id;
1501
1502         vmci_trans(vsk)->notify_ops->process_negotiate(sk);
1503
1504         return 0;
1505
1506 destroy:
1507         if (attach_sub_id != VMCI_INVALID_ID)
1508                 vmci_event_unsubscribe(attach_sub_id);
1509
1510         if (detach_sub_id != VMCI_INVALID_ID)
1511                 vmci_event_unsubscribe(detach_sub_id);
1512
1513         if (!vmci_handle_is_invalid(handle))
1514                 vmci_qpair_detach(&qpair);
1515
1516         return err;
1517 }
1518
1519 static int
1520 vmci_transport_recv_connecting_client_invalid(struct sock *sk,
1521                                               struct vmci_transport_packet *pkt)
1522 {
1523         int err = 0;
1524         struct vsock_sock *vsk = vsock_sk(sk);
1525
1526         if (vsk->sent_request) {
1527                 vsk->sent_request = false;
1528                 vsk->ignore_connecting_rst = true;
1529
1530                 err = vmci_transport_send_conn_request(
1531                         sk, vmci_trans(vsk)->queue_pair_size);
1532                 if (err < 0)
1533                         err = vmci_transport_error_to_vsock_error(err);
1534                 else
1535                         err = 0;
1536
1537         }
1538
1539         return err;
1540 }
1541
1542 static int vmci_transport_recv_connected(struct sock *sk,
1543                                          struct vmci_transport_packet *pkt)
1544 {
1545         struct vsock_sock *vsk;
1546         bool pkt_processed = false;
1547
1548         /* In cases where we are closing the connection, it's sufficient to
1549          * mark the state change (and maybe error) and wake up any waiting
1550          * threads. Since this is a connected socket, it's owned by a user
1551          * process and will be cleaned up when the failure is passed back on
1552          * the current or next system call.  Our system call implementations
1553          * must therefore check for error and state changes on entry and when
1554          * being awoken.
1555          */
1556         switch (pkt->type) {
1557         case VMCI_TRANSPORT_PACKET_TYPE_SHUTDOWN:
1558                 if (pkt->u.mode) {
1559                         vsk = vsock_sk(sk);
1560
1561                         vsk->peer_shutdown |= pkt->u.mode;
1562                         sk->sk_state_change(sk);
1563                 }
1564                 break;
1565
1566         case VMCI_TRANSPORT_PACKET_TYPE_RST:
1567                 vsk = vsock_sk(sk);
1568                 /* It is possible that we sent our peer a message (e.g a
1569                  * WAITING_READ) right before we got notified that the peer had
1570                  * detached. If that happens then we can get a RST pkt back
1571                  * from our peer even though there is data available for us to
1572                  * read. In that case, don't shutdown the socket completely but
1573                  * instead allow the local client to finish reading data off
1574                  * the queuepair. Always treat a RST pkt in connected mode like
1575                  * a clean shutdown.
1576                  */
1577                 sock_set_flag(sk, SOCK_DONE);
1578                 vsk->peer_shutdown = SHUTDOWN_MASK;
1579                 if (vsock_stream_has_data(vsk) <= 0)
1580                         sk->sk_state = SS_DISCONNECTING;
1581
1582                 sk->sk_state_change(sk);
1583                 break;
1584
1585         default:
1586                 vsk = vsock_sk(sk);
1587                 vmci_trans(vsk)->notify_ops->handle_notify_pkt(
1588                                 sk, pkt, false, NULL, NULL,
1589                                 &pkt_processed);
1590                 if (!pkt_processed)
1591                         return -EINVAL;
1592
1593                 break;
1594         }
1595
1596         return 0;
1597 }
1598
1599 static int vmci_transport_socket_init(struct vsock_sock *vsk,
1600                                       struct vsock_sock *psk)
1601 {
1602         vsk->trans = kmalloc(sizeof(struct vmci_transport), GFP_KERNEL);
1603         if (!vsk->trans)
1604                 return -ENOMEM;
1605
1606         vmci_trans(vsk)->dg_handle = VMCI_INVALID_HANDLE;
1607         vmci_trans(vsk)->qp_handle = VMCI_INVALID_HANDLE;
1608         vmci_trans(vsk)->qpair = NULL;
1609         vmci_trans(vsk)->produce_size = vmci_trans(vsk)->consume_size = 0;
1610         vmci_trans(vsk)->attach_sub_id = vmci_trans(vsk)->detach_sub_id =
1611                 VMCI_INVALID_ID;
1612         vmci_trans(vsk)->notify_ops = NULL;
1613         if (psk) {
1614                 vmci_trans(vsk)->queue_pair_size =
1615                         vmci_trans(psk)->queue_pair_size;
1616                 vmci_trans(vsk)->queue_pair_min_size =
1617                         vmci_trans(psk)->queue_pair_min_size;
1618                 vmci_trans(vsk)->queue_pair_max_size =
1619                         vmci_trans(psk)->queue_pair_max_size;
1620         } else {
1621                 vmci_trans(vsk)->queue_pair_size =
1622                         VMCI_TRANSPORT_DEFAULT_QP_SIZE;
1623                 vmci_trans(vsk)->queue_pair_min_size =
1624                          VMCI_TRANSPORT_DEFAULT_QP_SIZE_MIN;
1625                 vmci_trans(vsk)->queue_pair_max_size =
1626                         VMCI_TRANSPORT_DEFAULT_QP_SIZE_MAX;
1627         }
1628
1629         return 0;
1630 }
1631
1632 static void vmci_transport_destruct(struct vsock_sock *vsk)
1633 {
1634         if (vmci_trans(vsk)->attach_sub_id != VMCI_INVALID_ID) {
1635                 vmci_event_unsubscribe(vmci_trans(vsk)->attach_sub_id);
1636                 vmci_trans(vsk)->attach_sub_id = VMCI_INVALID_ID;
1637         }
1638
1639         if (vmci_trans(vsk)->detach_sub_id != VMCI_INVALID_ID) {
1640                 vmci_event_unsubscribe(vmci_trans(vsk)->detach_sub_id);
1641                 vmci_trans(vsk)->detach_sub_id = VMCI_INVALID_ID;
1642         }
1643
1644         if (!vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle)) {
1645                 vmci_qpair_detach(&vmci_trans(vsk)->qpair);
1646                 vmci_trans(vsk)->qp_handle = VMCI_INVALID_HANDLE;
1647                 vmci_trans(vsk)->produce_size = 0;
1648                 vmci_trans(vsk)->consume_size = 0;
1649         }
1650
1651         if (vmci_trans(vsk)->notify_ops)
1652                 vmci_trans(vsk)->notify_ops->socket_destruct(vsk);
1653
1654         kfree(vsk->trans);
1655         vsk->trans = NULL;
1656 }
1657
1658 static void vmci_transport_release(struct vsock_sock *vsk)
1659 {
1660         if (!vmci_handle_is_invalid(vmci_trans(vsk)->dg_handle)) {
1661                 vmci_datagram_destroy_handle(vmci_trans(vsk)->dg_handle);
1662                 vmci_trans(vsk)->dg_handle = VMCI_INVALID_HANDLE;
1663         }
1664 }
1665
1666 static int vmci_transport_dgram_bind(struct vsock_sock *vsk,
1667                                      struct sockaddr_vm *addr)
1668 {
1669         u32 port;
1670         u32 flags;
1671         int err;
1672
1673         /* VMCI will select a resource ID for us if we provide
1674          * VMCI_INVALID_ID.
1675          */
1676         port = addr->svm_port == VMADDR_PORT_ANY ?
1677                         VMCI_INVALID_ID : addr->svm_port;
1678
1679         if (port <= LAST_RESERVED_PORT && !capable(CAP_NET_BIND_SERVICE))
1680                 return -EACCES;
1681
1682         flags = addr->svm_cid == VMADDR_CID_ANY ?
1683                                 VMCI_FLAG_ANYCID_DG_HND : 0;
1684
1685         err = vmci_transport_datagram_create_hnd(port, flags,
1686                                                  vmci_transport_recv_dgram_cb,
1687                                                  &vsk->sk,
1688                                                  &vmci_trans(vsk)->dg_handle);
1689         if (err < VMCI_SUCCESS)
1690                 return vmci_transport_error_to_vsock_error(err);
1691         vsock_addr_init(&vsk->local_addr, addr->svm_cid,
1692                         vmci_trans(vsk)->dg_handle.resource);
1693
1694         return 0;
1695 }
1696
1697 static int vmci_transport_dgram_enqueue(
1698         struct vsock_sock *vsk,
1699         struct sockaddr_vm *remote_addr,
1700         struct msghdr *msg,
1701         size_t len)
1702 {
1703         int err;
1704         struct vmci_datagram *dg;
1705
1706         if (len > VMCI_MAX_DG_PAYLOAD_SIZE)
1707                 return -EMSGSIZE;
1708
1709         if (!vmci_transport_allow_dgram(vsk, remote_addr->svm_cid))
1710                 return -EPERM;
1711
1712         /* Allocate a buffer for the user's message and our packet header. */
1713         dg = kmalloc(len + sizeof(*dg), GFP_KERNEL);
1714         if (!dg)
1715                 return -ENOMEM;
1716
1717         memcpy_from_msg(VMCI_DG_PAYLOAD(dg), msg, len);
1718
1719         dg->dst = vmci_make_handle(remote_addr->svm_cid,
1720                                    remote_addr->svm_port);
1721         dg->src = vmci_make_handle(vsk->local_addr.svm_cid,
1722                                    vsk->local_addr.svm_port);
1723         dg->payload_size = len;
1724
1725         err = vmci_datagram_send(dg);
1726         kfree(dg);
1727         if (err < 0)
1728                 return vmci_transport_error_to_vsock_error(err);
1729
1730         return err - sizeof(*dg);
1731 }
1732
1733 static int vmci_transport_dgram_dequeue(struct vsock_sock *vsk,
1734                                         struct msghdr *msg, size_t len,
1735                                         int flags)
1736 {
1737         int err;
1738         int noblock;
1739         struct vmci_datagram *dg;
1740         size_t payload_len;
1741         struct sk_buff *skb;
1742
1743         noblock = flags & MSG_DONTWAIT;
1744
1745         if (flags & MSG_OOB || flags & MSG_ERRQUEUE)
1746                 return -EOPNOTSUPP;
1747
1748         /* Retrieve the head sk_buff from the socket's receive queue. */
1749         err = 0;
1750         skb = skb_recv_datagram(&vsk->sk, flags, noblock, &err);
1751         if (err)
1752                 return err;
1753
1754         if (!skb)
1755                 return -EAGAIN;
1756
1757         dg = (struct vmci_datagram *)skb->data;
1758         if (!dg)
1759                 /* err is 0, meaning we read zero bytes. */
1760                 goto out;
1761
1762         payload_len = dg->payload_size;
1763         /* Ensure the sk_buff matches the payload size claimed in the packet. */
1764         if (payload_len != skb->len - sizeof(*dg)) {
1765                 err = -EINVAL;
1766                 goto out;
1767         }
1768
1769         if (payload_len > len) {
1770                 payload_len = len;
1771                 msg->msg_flags |= MSG_TRUNC;
1772         }
1773
1774         /* Place the datagram payload in the user's iovec. */
1775         err = skb_copy_datagram_msg(skb, sizeof(*dg), msg, payload_len);
1776         if (err)
1777                 goto out;
1778
1779         if (msg->msg_name) {
1780                 /* Provide the address of the sender. */
1781                 DECLARE_SOCKADDR(struct sockaddr_vm *, vm_addr, msg->msg_name);
1782                 vsock_addr_init(vm_addr, dg->src.context, dg->src.resource);
1783                 msg->msg_namelen = sizeof(*vm_addr);
1784         }
1785         err = payload_len;
1786
1787 out:
1788         skb_free_datagram(&vsk->sk, skb);
1789         return err;
1790 }
1791
1792 static bool vmci_transport_dgram_allow(u32 cid, u32 port)
1793 {
1794         if (cid == VMADDR_CID_HYPERVISOR) {
1795                 /* Registrations of PBRPC Servers do not modify VMX/Hypervisor
1796                  * state and are allowed.
1797                  */
1798                 return port == VMCI_UNITY_PBRPC_REGISTER;
1799         }
1800
1801         return true;
1802 }
1803
1804 static int vmci_transport_connect(struct vsock_sock *vsk)
1805 {
1806         int err;
1807         bool old_pkt_proto = false;
1808         struct sock *sk = &vsk->sk;
1809
1810         if (vmci_transport_old_proto_override(&old_pkt_proto) &&
1811                 old_pkt_proto) {
1812                 err = vmci_transport_send_conn_request(
1813                         sk, vmci_trans(vsk)->queue_pair_size);
1814                 if (err < 0) {
1815                         sk->sk_state = SS_UNCONNECTED;
1816                         return err;
1817                 }
1818         } else {
1819                 int supported_proto_versions =
1820                         vmci_transport_new_proto_supported_versions();
1821                 err = vmci_transport_send_conn_request2(
1822                                 sk, vmci_trans(vsk)->queue_pair_size,
1823                                 supported_proto_versions);
1824                 if (err < 0) {
1825                         sk->sk_state = SS_UNCONNECTED;
1826                         return err;
1827                 }
1828
1829                 vsk->sent_request = true;
1830         }
1831
1832         return err;
1833 }
1834
1835 static ssize_t vmci_transport_stream_dequeue(
1836         struct vsock_sock *vsk,
1837         struct msghdr *msg,
1838         size_t len,
1839         int flags)
1840 {
1841         if (flags & MSG_PEEK)
1842                 return vmci_qpair_peekv(vmci_trans(vsk)->qpair, msg, len, 0);
1843         else
1844                 return vmci_qpair_dequev(vmci_trans(vsk)->qpair, msg, len, 0);
1845 }
1846
1847 static ssize_t vmci_transport_stream_enqueue(
1848         struct vsock_sock *vsk,
1849         struct msghdr *msg,
1850         size_t len)
1851 {
1852         return vmci_qpair_enquev(vmci_trans(vsk)->qpair, msg, len, 0);
1853 }
1854
1855 static s64 vmci_transport_stream_has_data(struct vsock_sock *vsk)
1856 {
1857         return vmci_qpair_consume_buf_ready(vmci_trans(vsk)->qpair);
1858 }
1859
1860 static s64 vmci_transport_stream_has_space(struct vsock_sock *vsk)
1861 {
1862         return vmci_qpair_produce_free_space(vmci_trans(vsk)->qpair);
1863 }
1864
1865 static u64 vmci_transport_stream_rcvhiwat(struct vsock_sock *vsk)
1866 {
1867         return vmci_trans(vsk)->consume_size;
1868 }
1869
1870 static bool vmci_transport_stream_is_active(struct vsock_sock *vsk)
1871 {
1872         return !vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle);
1873 }
1874
1875 static u64 vmci_transport_get_buffer_size(struct vsock_sock *vsk)
1876 {
1877         return vmci_trans(vsk)->queue_pair_size;
1878 }
1879
1880 static u64 vmci_transport_get_min_buffer_size(struct vsock_sock *vsk)
1881 {
1882         return vmci_trans(vsk)->queue_pair_min_size;
1883 }
1884
1885 static u64 vmci_transport_get_max_buffer_size(struct vsock_sock *vsk)
1886 {
1887         return vmci_trans(vsk)->queue_pair_max_size;
1888 }
1889
1890 static void vmci_transport_set_buffer_size(struct vsock_sock *vsk, u64 val)
1891 {
1892         if (val < vmci_trans(vsk)->queue_pair_min_size)
1893                 vmci_trans(vsk)->queue_pair_min_size = val;
1894         if (val > vmci_trans(vsk)->queue_pair_max_size)
1895                 vmci_trans(vsk)->queue_pair_max_size = val;
1896         vmci_trans(vsk)->queue_pair_size = val;
1897 }
1898
1899 static void vmci_transport_set_min_buffer_size(struct vsock_sock *vsk,
1900                                                u64 val)
1901 {
1902         if (val > vmci_trans(vsk)->queue_pair_size)
1903                 vmci_trans(vsk)->queue_pair_size = val;
1904         vmci_trans(vsk)->queue_pair_min_size = val;
1905 }
1906
1907 static void vmci_transport_set_max_buffer_size(struct vsock_sock *vsk,
1908                                                u64 val)
1909 {
1910         if (val < vmci_trans(vsk)->queue_pair_size)
1911                 vmci_trans(vsk)->queue_pair_size = val;
1912         vmci_trans(vsk)->queue_pair_max_size = val;
1913 }
1914
1915 static int vmci_transport_notify_poll_in(
1916         struct vsock_sock *vsk,
1917         size_t target,
1918         bool *data_ready_now)
1919 {
1920         return vmci_trans(vsk)->notify_ops->poll_in(
1921                         &vsk->sk, target, data_ready_now);
1922 }
1923
1924 static int vmci_transport_notify_poll_out(
1925         struct vsock_sock *vsk,
1926         size_t target,
1927         bool *space_available_now)
1928 {
1929         return vmci_trans(vsk)->notify_ops->poll_out(
1930                         &vsk->sk, target, space_available_now);
1931 }
1932
1933 static int vmci_transport_notify_recv_init(
1934         struct vsock_sock *vsk,
1935         size_t target,
1936         struct vsock_transport_recv_notify_data *data)
1937 {
1938         return vmci_trans(vsk)->notify_ops->recv_init(
1939                         &vsk->sk, target,
1940                         (struct vmci_transport_recv_notify_data *)data);
1941 }
1942
1943 static int vmci_transport_notify_recv_pre_block(
1944         struct vsock_sock *vsk,
1945         size_t target,
1946         struct vsock_transport_recv_notify_data *data)
1947 {
1948         return vmci_trans(vsk)->notify_ops->recv_pre_block(
1949                         &vsk->sk, target,
1950                         (struct vmci_transport_recv_notify_data *)data);
1951 }
1952
1953 static int vmci_transport_notify_recv_pre_dequeue(
1954         struct vsock_sock *vsk,
1955         size_t target,
1956         struct vsock_transport_recv_notify_data *data)
1957 {
1958         return vmci_trans(vsk)->notify_ops->recv_pre_dequeue(
1959                         &vsk->sk, target,
1960                         (struct vmci_transport_recv_notify_data *)data);
1961 }
1962
1963 static int vmci_transport_notify_recv_post_dequeue(
1964         struct vsock_sock *vsk,
1965         size_t target,
1966         ssize_t copied,
1967         bool data_read,
1968         struct vsock_transport_recv_notify_data *data)
1969 {
1970         return vmci_trans(vsk)->notify_ops->recv_post_dequeue(
1971                         &vsk->sk, target, copied, data_read,
1972                         (struct vmci_transport_recv_notify_data *)data);
1973 }
1974
1975 static int vmci_transport_notify_send_init(
1976         struct vsock_sock *vsk,
1977         struct vsock_transport_send_notify_data *data)
1978 {
1979         return vmci_trans(vsk)->notify_ops->send_init(
1980                         &vsk->sk,
1981                         (struct vmci_transport_send_notify_data *)data);
1982 }
1983
1984 static int vmci_transport_notify_send_pre_block(
1985         struct vsock_sock *vsk,
1986         struct vsock_transport_send_notify_data *data)
1987 {
1988         return vmci_trans(vsk)->notify_ops->send_pre_block(
1989                         &vsk->sk,
1990                         (struct vmci_transport_send_notify_data *)data);
1991 }
1992
1993 static int vmci_transport_notify_send_pre_enqueue(
1994         struct vsock_sock *vsk,
1995         struct vsock_transport_send_notify_data *data)
1996 {
1997         return vmci_trans(vsk)->notify_ops->send_pre_enqueue(
1998                         &vsk->sk,
1999                         (struct vmci_transport_send_notify_data *)data);
2000 }
2001
2002 static int vmci_transport_notify_send_post_enqueue(
2003         struct vsock_sock *vsk,
2004         ssize_t written,
2005         struct vsock_transport_send_notify_data *data)
2006 {
2007         return vmci_trans(vsk)->notify_ops->send_post_enqueue(
2008                         &vsk->sk, written,
2009                         (struct vmci_transport_send_notify_data *)data);
2010 }
2011
2012 static bool vmci_transport_old_proto_override(bool *old_pkt_proto)
2013 {
2014         if (PROTOCOL_OVERRIDE != -1) {
2015                 if (PROTOCOL_OVERRIDE == 0)
2016                         *old_pkt_proto = true;
2017                 else
2018                         *old_pkt_proto = false;
2019
2020                 pr_info("Proto override in use\n");
2021                 return true;
2022         }
2023
2024         return false;
2025 }
2026
2027 static bool vmci_transport_proto_to_notify_struct(struct sock *sk,
2028                                                   u16 *proto,
2029                                                   bool old_pkt_proto)
2030 {
2031         struct vsock_sock *vsk = vsock_sk(sk);
2032
2033         if (old_pkt_proto) {
2034                 if (*proto != VSOCK_PROTO_INVALID) {
2035                         pr_err("Can't set both an old and new protocol\n");
2036                         return false;
2037                 }
2038                 vmci_trans(vsk)->notify_ops = &vmci_transport_notify_pkt_ops;
2039                 goto exit;
2040         }
2041
2042         switch (*proto) {
2043         case VSOCK_PROTO_PKT_ON_NOTIFY:
2044                 vmci_trans(vsk)->notify_ops =
2045                         &vmci_transport_notify_pkt_q_state_ops;
2046                 break;
2047         default:
2048                 pr_err("Unknown notify protocol version\n");
2049                 return false;
2050         }
2051
2052 exit:
2053         vmci_trans(vsk)->notify_ops->socket_init(sk);
2054         return true;
2055 }
2056
2057 static u16 vmci_transport_new_proto_supported_versions(void)
2058 {
2059         if (PROTOCOL_OVERRIDE != -1)
2060                 return PROTOCOL_OVERRIDE;
2061
2062         return VSOCK_PROTO_ALL_SUPPORTED;
2063 }
2064
2065 static u32 vmci_transport_get_local_cid(void)
2066 {
2067         return vmci_get_context_id();
2068 }
2069
2070 static struct vsock_transport vmci_transport = {
2071         .init = vmci_transport_socket_init,
2072         .destruct = vmci_transport_destruct,
2073         .release = vmci_transport_release,
2074         .connect = vmci_transport_connect,
2075         .dgram_bind = vmci_transport_dgram_bind,
2076         .dgram_dequeue = vmci_transport_dgram_dequeue,
2077         .dgram_enqueue = vmci_transport_dgram_enqueue,
2078         .dgram_allow = vmci_transport_dgram_allow,
2079         .stream_dequeue = vmci_transport_stream_dequeue,
2080         .stream_enqueue = vmci_transport_stream_enqueue,
2081         .stream_has_data = vmci_transport_stream_has_data,
2082         .stream_has_space = vmci_transport_stream_has_space,
2083         .stream_rcvhiwat = vmci_transport_stream_rcvhiwat,
2084         .stream_is_active = vmci_transport_stream_is_active,
2085         .stream_allow = vmci_transport_stream_allow,
2086         .notify_poll_in = vmci_transport_notify_poll_in,
2087         .notify_poll_out = vmci_transport_notify_poll_out,
2088         .notify_recv_init = vmci_transport_notify_recv_init,
2089         .notify_recv_pre_block = vmci_transport_notify_recv_pre_block,
2090         .notify_recv_pre_dequeue = vmci_transport_notify_recv_pre_dequeue,
2091         .notify_recv_post_dequeue = vmci_transport_notify_recv_post_dequeue,
2092         .notify_send_init = vmci_transport_notify_send_init,
2093         .notify_send_pre_block = vmci_transport_notify_send_pre_block,
2094         .notify_send_pre_enqueue = vmci_transport_notify_send_pre_enqueue,
2095         .notify_send_post_enqueue = vmci_transport_notify_send_post_enqueue,
2096         .shutdown = vmci_transport_shutdown,
2097         .set_buffer_size = vmci_transport_set_buffer_size,
2098         .set_min_buffer_size = vmci_transport_set_min_buffer_size,
2099         .set_max_buffer_size = vmci_transport_set_max_buffer_size,
2100         .get_buffer_size = vmci_transport_get_buffer_size,
2101         .get_min_buffer_size = vmci_transport_get_min_buffer_size,
2102         .get_max_buffer_size = vmci_transport_get_max_buffer_size,
2103         .get_local_cid = vmci_transport_get_local_cid,
2104 };
2105
2106 static int __init vmci_transport_init(void)
2107 {
2108         int err;
2109
2110         /* Create the datagram handle that we will use to send and receive all
2111          * VSocket control messages for this context.
2112          */
2113         err = vmci_transport_datagram_create_hnd(VMCI_TRANSPORT_PACKET_RID,
2114                                                  VMCI_FLAG_ANYCID_DG_HND,
2115                                                  vmci_transport_recv_stream_cb,
2116                                                  NULL,
2117                                                  &vmci_transport_stream_handle);
2118         if (err < VMCI_SUCCESS) {
2119                 pr_err("Unable to create datagram handle. (%d)\n", err);
2120                 return vmci_transport_error_to_vsock_error(err);
2121         }
2122
2123         err = vmci_event_subscribe(VMCI_EVENT_QP_RESUMED,
2124                                    vmci_transport_qp_resumed_cb,
2125                                    NULL, &vmci_transport_qp_resumed_sub_id);
2126         if (err < VMCI_SUCCESS) {
2127                 pr_err("Unable to subscribe to resumed event. (%d)\n", err);
2128                 err = vmci_transport_error_to_vsock_error(err);
2129                 vmci_transport_qp_resumed_sub_id = VMCI_INVALID_ID;
2130                 goto err_destroy_stream_handle;
2131         }
2132
2133         err = vsock_core_init(&vmci_transport);
2134         if (err < 0)
2135                 goto err_unsubscribe;
2136
2137         return 0;
2138
2139 err_unsubscribe:
2140         vmci_event_unsubscribe(vmci_transport_qp_resumed_sub_id);
2141 err_destroy_stream_handle:
2142         vmci_datagram_destroy_handle(vmci_transport_stream_handle);
2143         return err;
2144 }
2145 module_init(vmci_transport_init);
2146
2147 static void __exit vmci_transport_exit(void)
2148 {
2149         if (!vmci_handle_is_invalid(vmci_transport_stream_handle)) {
2150                 if (vmci_datagram_destroy_handle(
2151                         vmci_transport_stream_handle) != VMCI_SUCCESS)
2152                         pr_err("Couldn't destroy datagram handle\n");
2153                 vmci_transport_stream_handle = VMCI_INVALID_HANDLE;
2154         }
2155
2156         if (vmci_transport_qp_resumed_sub_id != VMCI_INVALID_ID) {
2157                 vmci_event_unsubscribe(vmci_transport_qp_resumed_sub_id);
2158                 vmci_transport_qp_resumed_sub_id = VMCI_INVALID_ID;
2159         }
2160
2161         vsock_core_exit();
2162 }
2163 module_exit(vmci_transport_exit);
2164
2165 MODULE_AUTHOR("VMware, Inc.");
2166 MODULE_DESCRIPTION("VMCI transport for Virtual Sockets");
2167 MODULE_LICENSE("GPL v2");
2168 MODULE_ALIAS("vmware_vsock");
2169 MODULE_ALIAS_NETPROTO(PF_VSOCK);