bsd/sys/kpi_socket.h

   1 /*
   2  * Copyright (c) 2008-2017 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*!
  29         @header kpi_socket.h
  30         This header defines an API for creating and interacting with sockets
  31         in the kernel. It is possible to create sockets in the kernel
  32         without an associated file descriptor. In some cases, a reference to
  33         the socket may be known while the file descriptor is not. These
  34         functions can be used for interacting with sockets in the kernel.
  35         The API is similar to the user space socket API.
  36  */
  37 #ifndef __KPI_SOCKET__
  38 #define __KPI_SOCKET__
  39
  40 #include <sys/types.h>
  41 #include <sys/kernel_types.h>
  42 #include <sys/socket.h>
  43
  44 __BEGIN_DECLS
  45
  46 struct timeval;
  47
  48 /*!
  49         @typedef sock_upcall
  50
  51         @discussion sock_upcall is used by a socket to notify an in kernel
  52                 client that data is waiting. Instead of making blocking calls in
  53                 the kernel, a client can specify an upcall which will be called
  54                 when data is available or the socket is ready for sending.
  55
  56                 Calls to your upcall function are not serialized and may be
  57                 called concurrently from multiple threads in the kernel.
  58
  59                 Your upcall function will be called:
  60                     when there is data more than the low water mark for reading,
  61                     or when there is space for a write,
  62                     or when there is a connection to accept,
  63                     or when a socket is connected,
  64                     or when a socket is closed or disconnected
  65
  66         @param so A reference to the socket that's ready.
  67         @param cookie The cookie passed in when the socket was created.
  68         @param waitf Indicates whether or not it's safe to block.
  69 */
  70 typedef void (*sock_upcall)(socket_t so, void *cookie, int waitf);
  71
  72 #ifdef KERNEL_PRIVATE
  73 /*!
  74         @typedef sock_evupcall
  75
  76         @discussion sock_evupcall is used by a socket to notify an in kernel
  77                 client when an event occurs. Instead of making blocking calls in
  78                 the kernel, a client can specify an upcall which will be called
  79                 when an event status is available.
  80         @param so A reference to the socket that's ready.
  81         @param cookie The cookie passed in when the socket was created.
  82         @param event Indicates the event as defined by SO_FILT_HINT_*
  83 */
  84 typedef void (*sock_evupcall)(socket_t so, void *cookie, u_int32_t event);
  85 #endif /* KERNEL_PRIVATE */
  86
  87 /*!
  88         @function sock_accept
  89         @discussion Accepts an incoming connection on a socket. See 'man 2
  90                 accept' for more information. Allocating a socket in this manner
  91                 creates a socket with no associated file descriptor.
  92         @param so The listening socket you'd like to accept a connection on.
  93         @param from A pointer to a socket address that will be filled in
  94                 with the address the connection is from.
  95         @param fromlen Maximum length of from.
  96         @param flags Supports MSG_DONTWAIT and MSG_USEUPCALL. If
  97                 MSG_DONTWAIT is set, accept will return EWOULDBLOCK if there are
  98                 no connections ready to be accepted. If MSG_USEUPCALL is set,
  99                 the created socket will use the same upcall function attached to
 100                 the original socket.
 101         @param callback A notifier function to be called when an event
 102                 occurs on the socket. This may be NULL.
 103         @param cookie A cookie passed directly to the callback.
 104         @param new_so Upon success, *new_so will be a reference to a new
 105                 socket for tracking the connection.
 106         @result 0 on success otherwise the errno error.
 107  */
 108 #ifdef KERNEL_PRIVATE
 109 extern errno_t sock_accept_internal(socket_t so, struct sockaddr *from, int fromlen,
 110     int flags, sock_upcall callback, void *cookie, socket_t *new_so);
 111
 112 #define sock_accept(so, from, fromlen, flags, callback, cookie, new_so) \
 113         sock_accept_internal((so), (from), (fromlen), (flags), (callback), \
 114         (cookie), (new_so))
 115 #else
 116 extern errno_t sock_accept(socket_t so, struct sockaddr *from, int fromlen,
 117     int flags, sock_upcall callback, void *cookie, socket_t *new_so);
 118 #endif /* KERNEL_PRIVATE */
 119
 120 /*!
 121         @function sock_bind
 122         @discussion Binds a socket to a specific address. See 'man 2 bind'
 123                 for more information.
 124         @param so The socket to be bound.
 125         @param to The local address the socket should be bound to.
 126         @result 0 on success otherwise the errno error.
 127  */
 128 extern errno_t sock_bind(socket_t so, const struct sockaddr *to);
 129
 130 /*!
 131         @function sock_connect
 132         @discussion Initiates a connection on the socket. See 'man 2
 133                 connect' for more information.
 134         @param so The socket to be connect.
 135         @param to The remote address the socket should connect to.
 136         @param flags Flags for connecting. The only flag supported so far is
 137                 MSG_DONTWAIT. MSG_DONTWAIT will perform a non-blocking connect.
 138                 sock_connect will return immediately with EINPROGRESS. The
 139                 upcall, if supplied, will be called when the connection is
 140                 completed.
 141         @result 0 on success, EINPROGRESS for a non-blocking connect that
 142                 has not completed, otherwise the errno error.
 143  */
 144 extern errno_t sock_connect(socket_t so, const struct sockaddr *to, int flags);
 145
 146 #ifdef KERNEL_PRIVATE
 147 /*
 148         This function was added to support NFS. NFS does something funny,
 149         setting a short timeout and checking to see if it should abort the
 150         connect every two seconds. Ideally, NFS would use the upcall to be
 151         notified when the connect is complete.
 152
 153         If you feel you need to use this function, please contact us to
 154         explain why.
 155
 156         @function sock_connectwait
 157         @discussion Allows a caller to wait on a socket connect.
 158         @param so The socket being connected.
 159         @param tv The amount of time to wait.
 160         @result 0 on success otherwise the errno error. EINPROGRESS will be
 161                 returned if the connection did not complete in the timeout
 162                 specified.
 163  */
 164 extern errno_t sock_connectwait(socket_t so, const struct timeval *tv);
 165 #endif /* KERNEL_PRIVATE */
 166
 167 /*!
 168         @function sock_getpeername
 169         @discussion Retrieves the remote address of a connected socket. See
 170                 'man 2 getpeername'.
 171         @param so The socket.
 172         @param peername Storage for the peer name.
 173         @param peernamelen Length of storage for the peer name.
 174         @result 0 on success otherwise the errno error.
 175  */
 176 extern errno_t sock_getpeername(socket_t so, struct sockaddr *peername,
 177     int peernamelen);
 178
 179 /*!
 180         @function sock_getsockname
 181         @discussion Retrieves the local address of a socket. See 'man 2
 182                 getsockname'.
 183         @param so The socket.
 184         @param sockname Storage for the local name.
 185         @param socknamelen Length of storage for the socket name.
 186         @result 0 on success otherwise the errno error.
 187  */
 188 extern errno_t sock_getsockname(socket_t so, struct sockaddr *sockname,
 189     int socknamelen);
 190
 191 /*!
 192         @function sock_getsockopt
 193         @discussion Retrieves a socket option. See 'man 2 getsockopt'.
 194         @param so The socket.
 195         @param level Level of the socket option.
 196         @param optname The option name.
 197         @param optval The option value.
 198         @param optlen The length of optval, returns the actual length.
 199         @result 0 on success otherwise the errno error.
 200  */
 201 extern errno_t sock_getsockopt(socket_t so, int level, int optname,
 202     void *optval, int *optlen);
 203
 204 /*!
 205         @function sock_ioctl
 206         @discussion Performs an ioctl operation on a socket. See 'man 2 ioctl'.
 207         @param so The socket.
 208         @param request The ioctl name.
 209         @param argp The argument.
 210         @result 0 on success otherwise the errno error.
 211  */
 212 extern errno_t sock_ioctl(socket_t so, unsigned long request, void *argp);
 213
 214 /*!
 215         @function sock_setsockopt
 216         @discussion Sets a socket option. See 'man 2 setsockopt'.
 217         @param so The socket.
 218         @param level Level of the socket option.
 219         @param optname The option name.
 220         @param optval The option value.
 221         @param optlen The length of optval.
 222         @result 0 on success otherwise the errno error.
 223  */
 224 extern errno_t sock_setsockopt(socket_t so, int level, int optname,
 225     const void *optval, int optlen);
 226
 227 #ifdef KERNEL_PRIVATE
 228 /*
 229         This function was added to support AFP setting the traffic class
 230         for a backup stream within a wireless LAN or over link-local address.
 231
 232         If you feel you need to use this function, please contact us to
 233         explain why.
 234
 235         @function sock_settclassopt
 236         @discussion Allows a caller to set the traffic class.
 237         @param so The socket.
 238         @param optval The option value.
 239         @param optlen The length of optval.
 240         @result 0 on success otherwise the errno error.
 241  */
 242 extern errno_t sock_settclassopt(socket_t so, const void* optval, size_t optlen);
 243
 244 /*
 245         This function was added to support AFP getting the traffic class
 246         set on a stream.
 247
 248         This is also a private API, please contact us if you need to use it.
 249
 250         @function sockgettclassopt
 251         @discussion Allows a caller to get the traffic class.
 252         @param so The socket.
 253         @param optval The option value.
 254         @param optlen The length of optval, returns the actual length.
 255         @result 0 on success otherwise the errno error.
 256 */
 257 extern errno_t sock_gettclassopt(socket_t so, void* optval, size_t* optlen);
 258
 259 #ifdef XNU_KERNEL_PRIVATE
 260 extern void socket_set_traffic_mgt_flags_locked(socket_t so, u_int8_t flags);
 261 extern void socket_clear_traffic_mgt_flags_locked(socket_t so, u_int8_t flags);
 262 #endif /* XNU_KERNEL_PRIVATE */
 263 #ifdef BSD_KERNEL_PRIVATE
 264 extern void socket_set_traffic_mgt_flags(socket_t so, u_int8_t flags);
 265 extern void socket_clear_traffic_mgt_flags(socket_t so, u_int8_t flags);
 266 extern errno_t socket_defunct(struct proc *, socket_t so, int);
 267 extern errno_t sock_receive_internal(socket_t, struct msghdr *, mbuf_t *,
 268     int, size_t *);
 269 #endif /* BSD_KERNEL_PRIVATE */
 270 #endif /* KERNEL_PRIVATE */
 271
 272 /*!
 273         @function sock_listen
 274         @discussion Indicate that the socket should start accepting incoming
 275                 connections. See 'man 2 listen'.
 276         @param so The socket.
 277         @param backlog The maximum length of the queue of pending connections.
 278         @result 0 on success otherwise the errno error.
 279  */
 280 extern errno_t sock_listen(socket_t so, int backlog);
 281
 282 /*!
 283         @function sock_receive
 284         @discussion Receive data from a socket. Similar to recvmsg. See 'man
 285                 2 recvmsg' for more information about receiving data.
 286         @param so The socket.
 287         @param msg The msg describing how the data should be received.
 288         @param flags See 'man 2 recvmsg'.
 289         @param recvdlen Number of bytes received, same as return value of
 290                 userland recvmsg.
 291         @result 0 on success, EWOULDBLOCK if non-blocking and operation
 292                 would cause the thread to block, otherwise the errno error.
 293  */
 294 extern errno_t sock_receive(socket_t so, struct msghdr *msg, int flags,
 295     size_t *recvdlen);
 296
 297 /*!
 298         @function sock_receivembuf
 299         @discussion Receive data from a socket. Similar to sock_receive
 300                 though data is returned as a chain of mbufs. See 'man 2 recvmsg'
 301                 for more information about receiving data.
 302         @param so The socket.
 303         @param msg The msg describing how the data should be received. May
 304                 be NULL. The msg_iov is ignored.
 305         @param data Upon return *data will be a reference to an mbuf chain
 306                 containing the data received. This eliminates copying the data
 307                 out of the mbufs. Caller is responsible for freeing the mbufs.
 308         @param flags See 'man 2 recvmsg'.
 309         @param recvlen Maximum number of bytes to receive in the mbuf chain.
 310                 Upon return, this value will be set to the number of bytes
 311                 received, same as return value of userland recvmsg.
 312         @result 0 on success, EWOULDBLOCK if non-blocking and operation
 313                 would cause the thread to block, otherwise the errno error.
 314  */
 315 extern errno_t sock_receivembuf(socket_t so, struct msghdr *msg, mbuf_t *data,
 316     int flags, size_t *recvlen);
 317
 318 /*!
 319         @function sock_send
 320         @discussion Send data on a socket. Similar to sendmsg. See 'man 2
 321                 sendmsg' for more information about sending data.
 322         @param so The socket.
 323         @param msg The msg describing how the data should be sent. Any
 324                 pointers must point to data in the kernel.
 325         @param flags See 'man 2 sendmsg'.
 326         @param sentlen The number of bytes sent.
 327         @result 0 on success, EWOULDBLOCK if non-blocking and operation
 328                 would cause the thread to block, otherwise the errno error.
 329  */
 330 extern errno_t sock_send(socket_t so, const struct msghdr *msg, int flags,
 331     size_t *sentlen);
 332
 333 /*!
 334         @function sock_sendmbuf
 335         @discussion Send data in an mbuf on a socket. Similar to sock_send
 336                 only the data to be sent is taken from the mbuf chain.
 337         @param so The socket.
 338         @param msg The msg describing how the data should be sent. The
 339                 msg_iov is ignored. msg may be NULL.
 340         @param data The mbuf chain of data to send.
 341         @param flags See 'man 2 sendmsg'.
 342         @param sentlen The number of bytes sent.
 343         @result 0 on success, EWOULDBLOCK if non-blocking and operation
 344                 would cause the thread to block, otherwise the errno error.
 345                 Regardless of return value, the mbuf chain 'data' will be freed.
 346  */
 347 extern errno_t sock_sendmbuf(socket_t so, const struct msghdr *msg, mbuf_t data,
 348     int flags, size_t *sentlen);
 349
 350 /*!
 351         @function sock_shutdown
 352         @discussion Shutdown one or both directions of a connection. See
 353                 'man 2 shutdown' for more information.
 354         @param so The socket.
 355         @param how SHUT_RD - shutdown receive.
 356                 SHUT_WR - shutdown send.
 357                 SHUT_RDWR - shutdown both.
 358         @result 0 on success otherwise the errno error.
 359  */
 360 extern errno_t sock_shutdown(socket_t so, int how);
 361
 362 /*!
 363         @function sock_socket
 364         @discussion Allocate a socket. Allocating a socket in this manner
 365                 creates a socket with no associated file descriptor. For more
 366                 information, see 'man 2 socket'.
 367         @param domain The socket domain (PF_INET, etc...).
 368         @param type The socket type (SOCK_STREAM, SOCK_DGRAM, etc...).
 369         @param protocol The socket protocol.
 370         @param callback A notifier function to be called when an event
 371                 occurs on the socket. This may be NULL.
 372         @param cookie A cookie passed directly to the callback.
 373         @param new_so Upon success, a reference to the new socket.
 374         @result 0 on success otherwise the errno error.
 375  */
 376 #ifdef KERNEL_PRIVATE
 377 extern errno_t sock_socket_internal(int domain, int type, int protocol,
 378     sock_upcall callback, void *cookie, socket_t *new_so);
 379
 380 #define sock_socket(domain, type, protocol, callback, cookie, new_so) \
 381         sock_socket_internal((domain), (type), (protocol), \
 382         (callback), (cookie), (new_so))
 383 #else
 384 extern errno_t sock_socket(int domain, int type, int protocol,
 385     sock_upcall callback, void *cookie, socket_t *new_so);
 386 #endif /* KERNEL_PRIVATE */
 387
 388 /*!
 389         @function sock_close
 390         @discussion Close the socket.
 391         @param so The socket to close. This should only ever be a socket
 392                 created with sock_socket. Closing a socket created in user space
 393                 using sock_close may leave a file descriptor pointing to the
 394                 closed socket, resulting in undefined behavior.
 395  */
 396 extern void sock_close(socket_t so);
 397
 398 #ifdef KERNEL_PRIVATE
 399 /*
 400         @function sock_retain
 401         @discussion Prevents the socket from closing
 402         @param so The socket to close.  Increment a retain count on the
 403                 socket, preventing it from being closed when sock_close is
 404                 called. This is used when a File Descriptor is passed (and
 405                 closed) from userland and the kext wants to keep ownership of
 406                 that socket. It is used in conjunction with
 407                 sock_release(socket_t so).
 408  */
 409 extern void sock_retain(socket_t so);
 410
 411 /*
 412         @function sock_release
 413         @discussion Decrement the retain count and close the socket if the
 414                 retain count reaches zero.
 415         @param so The socket to release. This is used to release ownership
 416                 on a socket acquired with sock_retain. When the last retain
 417                 count is reached, this will call sock_close to close the socket.
 418  */
 419 extern void sock_release(socket_t so);
 420 #endif /* KERNEL_PRIVATE */
 421
 422 /*!
 423         @function sock_setpriv
 424         @discussion Set the privileged bit in the socket. Allows for
 425                 operations that require root privileges.
 426         @param so The socket on which to modify the SS_PRIV flag.
 427         @param on Indicate whether or not the SS_PRIV flag should be set.
 428         @result 0 on success otherwise the errno error.
 429  */
 430 extern errno_t sock_setpriv(socket_t so, int on);
 431
 432 /*!
 433         @function sock_isconnected
 434         @discussion Returns whether or not the socket is connected.
 435         @param so The socket to check.
 436         @result 0 - socket is not connected. 1 - socket is connected.
 437  */
 438 extern int sock_isconnected(socket_t so);
 439
 440 /*!
 441         @function sock_isnonblocking
 442         @discussion Returns whether or not the socket is non-blocking. In
 443                 the context of this KPI, non-blocking means that functions to
 444                 perform operations on a socket will not wait for completion.
 445
 446                 To enable or disable blocking, use the FIONBIO ioctl. The
 447                 parameter is an int. If the int is zero, the socket will block.
 448                 If the parameter is non-zero, the socket will not block.
 449         @result 0 - socket will block. 1 - socket will not block.
 450  */
 451 extern int sock_isnonblocking(socket_t so);
 452
 453 /*!
 454         @function sock_gettype
 455         @discussion Retrieves information about the socket. This is the same
 456                 information that was used to create the socket. If any of the
 457                 parameters following so are NULL, that information is not
 458                 retrieved.
 459         @param so The socket to check.
 460         @param domain The domain of the socket (PF_INET, ...). May be NULL.
 461         @param type The socket type (SOCK_STREAM, SOCK_DGRAM, ...). May be NULL.
 462         @param protocol The socket protocol. May be NULL.
 463         @result 0 on success otherwise the errno error.
 464  */
 465 extern errno_t sock_gettype(socket_t so, int *domain, int *type, int *protocol);
 466
 467 #ifdef KERNEL_PRIVATE
 468 /*
 469         @function sock_nointerrupt
 470         @discussion Disables interrupt on socket buffers (sets SB_NOINTR on
 471                 send and receive socket buffers).
 472         @param so The socket to modify.
 473         @param on Indicate whether or not the SB_NOINTR flag should be set.
 474         @result 0 on success otherwise the errno error.
 475  */
 476 extern errno_t sock_nointerrupt(socket_t so, int on);
 477
 478 /*
 479         @function sock_getlistener
 480         @discussion Retrieves the listening socket of a pre-accepted socket,
 481                 i.e. a socket which is still in the incomplete/completed list.
 482                 Once a socket has been accepted, the information pertaining
 483                 to its listener is no longer available.  Therefore, modules
 484                 interested in finding out the listening socket should install
 485                 the appropriate socket filter callback (sf_attach) which gets
 486                 invoked prior to the socket being fully accepted, and call
 487                 this routine at such a time to obtain the listener.  Callers
 488                 are guaranteed that the listener socket will not go away
 489                 during the sf_attach callback, and therefore the value is
 490                 safe to be used only in that callback context.  Callers should
 491                 therefore take note that the listening socket's lock will be
 492                 held throughout the duration of the callback.
 493         @param so The pre-accepted socket.
 494         @result Non-NULL value which indicates the listening socket; otherwise,
 495                 NULL if the socket is not in the incomplete/completed list
 496                 of a listener.
 497  */
 498 extern socket_t sock_getlistener(socket_t so);
 499
 500 /*
 501         @function sock_getaddr
 502         @discussion Retrieves the local or remote address of a socket.
 503                 This is a composite of sock_getpeername and sock_getsockname,
 504                 except that the allocated socket address is returned to the
 505                 caller, and that the caller is reponsible for calling
 506                 sock_freeaddr once finished with it.
 507         @param so The socket.
 508         @param psockname Pointer to the storage for the socket name.
 509         @param peername 0 for local address, and non-zero for peer address.
 510         @result 0 on success otherwise the errno error.
 511  */
 512 extern errno_t sock_getaddr(socket_t so, struct sockaddr **psockname,
 513     int peername);
 514
 515 /*
 516         @function sock_freeaddr
 517         @discussion Frees the socket address allocated by sock_getaddr.
 518         @param sockname The socket name to be freed.
 519  */
 520 extern void sock_freeaddr(struct sockaddr *sockname);
 521
 522 /*
 523         @function sock_setupcall
 524         @discussion Set the notifier function to be called when an event
 525                 occurs on the socket. This may be set to NULL to disable
 526                 further notifications. Setting the function does not
 527                 affect currently notifications about to be sent or being sent.
 528                 Note: When this function is used on a socket passed from
 529                 userspace it is crucial to call sock_retain() on the socket
 530                 otherwise a callback could be dispatched on a closed socket
 531                 and cause a crash.
 532         @param sock The socket.
 533         @param callback The notifier function
 534         @param context A cookie passed directly to the callback
 535 */
 536 extern errno_t sock_setupcall(socket_t sock, sock_upcall callback,
 537     void *context);
 538
 539 /*
 540         @function sock_setupcalls
 541         @discussion Set the notifier function to be called when an event
 542                 occurs on the socket. This may be set to NULL to disable
 543                 further notifications. Setting the function does not
 544                 affect currently notifications about to be sent or being sent.
 545                 Note: When this function is used on a socket passed from
 546                 userspace it is crucial to call sock_retain() on the socket
 547                 otherwise a callback could be dispatched on a closed socket
 548                 and cause a crash.
 549         @param sock The socket.
 550         @param read_callback The read notifier function
 551         @param read_context A cookie passed directly to the read callback
 552         @param write_callback The write notifier function
 553         @param write_context A cookie passed directly to the write callback
 554 */
 555 extern errno_t sock_setupcalls(socket_t sock, sock_upcall read_callback,
 556     void *read_context, sock_upcall write_callback, void *write_context);
 557
 558 /*
 559         @function sock_setupcalls_locked
 560         @discussion The locked version of sock_setupcalls
 561         @param locked: When sets, indicates that the callbacks expect to be
 562                        on a locked socket. Thus, no unlock is done prior to
 563                        calling the callback.
 564  */
 565 extern void sock_setupcalls_locked(socket_t sock,
 566     sock_upcall rcallback, void *rcontext,
 567     sock_upcall wcallback, void *wcontext, int locked);
 568
 569 /*
 570         @function sock_catchevents
 571         @discussion Set the notifier function to be called when an event
 572                 occurs on the socket. This may be set to NULL to disable
 573                 further notifications. Setting the function does not
 574                 affect currently notifications about to be sent or being sent.
 575         @param sock The socket.
 576         @param event_callback The event notifier function
 577         @param event_context A cookie passed directly to the event callback
 578         @param event_mask One or more SO_FILT_HINT_* values OR'ed together,
 579                 indicating the registered event(s).
 580 */
 581 extern errno_t sock_catchevents(socket_t sock, sock_evupcall event_callback,
 582     void *event_context, u_int32_t event_mask);
 583
 584 extern void sock_catchevents_locked(socket_t sock, sock_evupcall ecallback,
 585     void *econtext, u_int32_t emask);
 586
 587
 588 /*
 589         @function sock_iskernel
 590         @discussion Returns true if the socket was created by the kernel or
 591                 is owned by the kernel.
 592         @param sock The socket.
 593         @result True if the kernel owns the socket.
 594 */
 595 extern int sock_iskernel(socket_t);
 596 #endif /* KERNEL_PRIVATE */
 597
 598 __END_DECLS
 599 #endif /* __KPI_SOCKET__ */