1/* 2 * Copyright (c) 2004 Apple Computer, 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, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 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 46struct 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 when: 60 61 @param so A reference to the socket that's ready. 62 @param cookie The cookie passed in when the socket was created. 63 @param waitf Indicates whether or not it's safe to block. 64*/ 65typedef void (*sock_upcall)(socket_t so, void* cookie, int waitf); 66 67/*! 68 @function sock_accept 69 @discussion Accepts an incoming connection on a socket. See 'man 2 70 accept' for more information. Allocating a socket in this manner 71 creates a socket with no associated file descriptor. 72 @param so The listening socket you'd like to accept a connection on. 73 @param from A pointer to a socket address that will be filled in 74 with the address the connection is from. 75 @param fromlen Maximum length of from. 76 @param flags Supports MSG_DONTWAIT and MSG_USEUPCALL. If 77 MSG_DONTWAIT is set, accept will return EWOULDBLOCK if there are 78 no connections ready to be accepted. If MSG_USEUPCALL is set, 79 the created socket will use the same upcall function attached to 80 the original socket. 81 @param callback A notifier function to be called when an event 82 occurs on the socket. This may be NULL. 83 @param cookie A cookie passed directly to the callback. 84 @param new_so Upon success, *new_so will be a reference to a new 85 socket for tracking the connection. 86 @result 0 on success otherwise the errno error. 87 */ 88errno_t sock_accept(socket_t so, struct sockaddr *from, int fromlen, 89 int flags, sock_upcall callback, void* cookie, socket_t *new_so); 90 91/*! 92 @function sock_bind 93 @discussion Binds a socket to a specific address. See 'man 2 bind' 94 for more information. 95 @param so The socket to be bound. 96 @param to The local address the socket should be bound to. 97 @result 0 on success otherwise the errno error. 98 */ 99errno_t sock_bind(socket_t so, const struct sockaddr *to); 100 101/*! 102 @function sock_connect 103 @discussion Initiates a connection on the socket. See 'man 2 104 connect' for more information. 105 @param so The socket to be connect. 106 @param to The remote address the socket should connect to. 107 @param flags Flags for connecting. The only flag supported so far is 108 MSG_DONTWAIT. MSG_DONTWAIT will perform a non-blocking connect. 109 sock_connect will return immediately with EINPROGRESS. The 110 upcall, if supplied, will be called when the connection is 111 completed. 112 @result 0 on success, EINPROGRESS for a non-blocking connect that 113 has not completed, otherwise the errno error. 114 */ 115errno_t sock_connect(socket_t so, const struct sockaddr *to, int flags); 116 117#ifdef KERNEL_PRIVATE 118/* 119 This function was added to support NFS. NFS does something funny, 120 setting a short timeout and checking to see if it should abort the 121 connect every two seconds. Ideally, NFS would use the upcall to be 122 notified when the connect is complete. 123 124 If you feel you need to use this function, please contact us to 125 explain why. 126 127 @function sock_connectwait 128 @discussion Allows a caller to wait on a socket connect. 129 @param so The socket being connected. 130 @param tv The amount of time to wait. 131 @result 0 on success otherwise the errno error. EINPROGRESS will be 132 returned if the connection did not complete in the timeout 133 specified. 134 */ 135errno_t sock_connectwait(socket_t so, const struct timeval *tv); 136#endif /* KERNEL_PRIVATE */ 137 138/*! 139 @function sock_getpeername 140 @discussion Retrieves the remote address of a connected socket. See 141 'man 2 getpeername'. 142 @param so The socket. 143 @param peername Storage for the peer name. 144 @param peernamelen Length of storage for the peer name. 145 @result 0 on success otherwise the errno error. 146 */ 147errno_t sock_getpeername(socket_t so, struct sockaddr *peername, 148 int peernamelen); 149 150/*! 151 @function sock_getsockname 152 @discussion Retrieves the local address of a socket. See 'man 2 153 getsockname'. 154 @param so The socket. 155 @param sockname Storage for the local name. 156 @param socknamelen Length of storage for the socket name. 157 @result 0 on success otherwise the errno error. 158 */ 159errno_t sock_getsockname(socket_t so, struct sockaddr *sockname, 160 int socknamelen); 161 162/*! 163 @function sock_getsockopt 164 @discussion Retrieves a socket option. See 'man 2 getsockopt'. 165 @param so The socket. 166 @param level Level of the socket option. 167 @param optname The option name. 168 @param optval The option value. 169 @param optlen The length of optval, returns the actual length. 170 @result 0 on success otherwise the errno error. 171 */ 172errno_t sock_getsockopt(socket_t so, int level, int optname, void *optval, 173 int *optlen); 174 175/*! 176 @function sock_ioctl 177 @discussion Performs an ioctl operation on a socket. See 'man 2 ioctl'. 178 @param so The socket. 179 @param request The ioctl name. 180 @param argp The argument. 181 @result 0 on success otherwise the errno error. 182 */ 183errno_t sock_ioctl(socket_t so, unsigned long request, void *argp); 184 185/*! 186 @function sock_setsockopt 187 @discussion Sets a socket option. See 'man 2 setsockopt'. 188 @param so The socket. 189 @param level Level of the socket option. 190 @param optname The option name. 191 @param optval The option value. 192 @param optlen The length of optval. 193 @result 0 on success otherwise the errno error. 194 */ 195errno_t sock_setsockopt(socket_t so, int level, int optname, const void *optval, 196 int optlen); 197 198/*! 199 @function sock_listen 200 @discussion Indicate that the socket should start accepting incoming 201 connections. See 'man 2 listen'. 202 @param so The socket. 203 @param backlog The maximum length of the queue of pending connections. 204 @result 0 on success otherwise the errno error. 205 */ 206errno_t sock_listen(socket_t so, int backlog); 207 208/*! 209 @function sock_receive 210 @discussion Receive data from a socket. Similar to recvmsg. See 'man 211 2 recvmsg' for more information about receiving data. 212 @param so The socket. 213 @param msg The msg describing how the data should be received. 214 @param flags See 'man 2 recvmsg'. 215 @param recvdlen Number of bytes received, same as return value of 216 userland recvmsg. 217 @result 0 on success, EWOULDBLOCK if non-blocking and operation 218 would cause the thread to block, otherwise the errno error. 219 */ 220errno_t sock_receive(socket_t so, struct msghdr *msg, int flags, 221 size_t *recvdlen); 222 223/*! 224 @function sock_receivembuf 225 @discussion Receive data from a socket. Similar to sock_receive 226 though data is returned as a chain of mbufs. See 'man 2 recvmsg' 227 for more information about receiving data. 228 @param so The socket. 229 @param msg The msg describing how the data should be received. May 230 be NULL. The msg_iov is ignored. 231 @param data Upon return *data will be a reference to an mbuf chain 232 containing the data received. This eliminates copying the data 233 out of the mbufs. Caller is responsible for freeing the mbufs. 234 @param flags See 'man 2 recvmsg'. 235 @param recvlen Maximum number of bytes to receive in the mbuf chain. 236 Upon return, this value will be set to the number of bytes 237 received, same as return value of userland recvmsg. 238 @result 0 on success, EWOULDBLOCK if non-blocking and operation 239 would cause the thread to block, otherwise the errno error. 240 */ 241errno_t sock_receivembuf(socket_t so, struct msghdr *msg, mbuf_t *data, 242 int flags, size_t *recvlen); 243 244/*! 245 @function sock_send 246 @discussion Send data on a socket. Similar to sendmsg. See 'man 2 247 sendmsg' for more information about sending data. 248 @param so The socket. 249 @param msg The msg describing how the data should be sent. Any 250 pointers must point to data in the kernel. 251 @param flags See 'man 2 sendmsg'. 252 @param sentlen The number of bytes sent. 253 @result 0 on success, EWOULDBLOCK if non-blocking and operation 254 would cause the thread to block, otherwise the errno error. 255 */ 256errno_t sock_send(socket_t so, const struct msghdr *msg, int flags, 257 size_t *sentlen); 258 259/*! 260 @function sock_sendmbuf 261 @discussion Send data in an mbuf on a socket. Similar to sock_send 262 only the data to be sent is taken from the mbuf chain. 263 @param so The socket. 264 @param msg The msg describing how the data should be sent. The 265 msg_iov is ignored. msg may be NULL. 266 @param data The mbuf chain of data to send. 267 @param flags See 'man 2 sendmsg'. 268 @param sentlen The number of bytes sent. 269 @result 0 on success, EWOULDBLOCK if non-blocking and operation 270 would cause the thread to block, otherwise the errno error. 271 Regardless of return value, the mbuf chain 'data' will be freed. 272 */ 273errno_t sock_sendmbuf(socket_t so, const struct msghdr *msg, mbuf_t data, 274 int flags, size_t *sentlen); 275 276/*! 277 @function sock_shutdown 278 @discussion Shutdown one or both directions of a connection. See 279 'man 2 shutdown' for more information. 280 @param so The socket. 281 @param how SHUT_RD - shutdown receive. SHUT_WR - shutdown send. SHUT_RDWR - shutdown both. 282 @result 0 on success otherwise the errno error. 283 */ 284errno_t sock_shutdown(socket_t so, int how); 285 286/*! 287 @function sock_socket 288 @discussion Allocate a socket. Allocating a socket in this manner 289 creates a socket with no associated file descriptor. For more 290 information, see 'man 2 socket'. 291 @param domain The socket domain (PF_INET, etc...). 292 @param type The socket type (SOCK_STREAM, SOCK_DGRAM, etc...). 293 @param protocol The socket protocol. 294 @param callback A notifier function to be called when an event 295 occurs on the socket. This may be NULL. 296 @param cookie A cookie passed directly to the callback. 297 @param new_so Upon success, a reference to the new socket. 298 @result 0 on success otherwise the errno error. 299 */ 300errno_t sock_socket(int domain, int type, int protocol, sock_upcall callback, 301 void* cookie, socket_t *new_so); 302 303/*! 304 @function sock_close 305 @discussion Close the socket. 306 @param so The socket to close. This should only ever be a socket 307 created with sock_socket. Closing a socket created in user space 308 using sock_close may leave a file descriptor pointing to the closed 309 socket, resulting in undefined behavior. 310 */ 311void sock_close(socket_t so); 312 313#ifdef KERNEL_PRIVATE 314/* 315 @function sock_retain 316 @discussion Prevents the socket from closing 317 @param so The socket to close. Increment a retain count on the 318 socket, preventing it from being closed when sock_close is 319 called. This is used when a File Descriptor is passed (and 320 closed) from userland and the kext wants to keep ownership of 321 that socket. It is used in conjunction with 322 sock_release(socket_t so). 323 */ 324void sock_retain(socket_t so); 325 326/* 327 @function sock_release 328 @discussion Decrement the retain count and close the socket if the 329 retain count reaches zero. 330 @param so The socket to release. This is used to release ownership 331 on a socket acquired with sock_retain. When the last retain 332 count is reached, this will call sock_close to close the socket. 333 */ 334void sock_release(socket_t so); 335#endif /* KERNEL_PRIVATE */ 336 337/*! 338 @function sock_setpriv 339 @discussion Set the privileged bit in the socket. Allows for 340 operations that require root privileges. 341 @param so The socket on which to modify the SS_PRIV flag. 342 @param on Indicate whether or not the SS_PRIV flag should be set. 343 @result 0 on success otherwise the errno error. 344 */ 345errno_t sock_setpriv(socket_t so, int on); 346 347/*! 348 @function sock_isconnected 349 @discussion Returns whether or not the socket is connected. 350 @param so The socket to check. 351 @result 0 - socket is not connected. 1 - socket is connected. 352 */ 353int sock_isconnected(socket_t so); 354 355/*! 356 @function sock_isnonblocking 357 @discussion Returns whether or not the socket is non-blocking. In 358 the context of this KPI, non-blocking means that functions to 359 perform operations on a socket will not wait for completion. 360 361 To enable or disable blocking, use the FIONBIO ioctl. The 362 parameter is an int. If the int is zero, the socket will block. 363 If the parameter is non-zero, the socket will not block. 364 @result 0 - socket will block. 1 - socket will not block. 365 */ 366int sock_isnonblocking(socket_t so); 367 368/*! 369 @function sock_gettype 370 @discussion Retrieves information about the socket. This is the same 371 information that was used to create the socket. If any of the 372 parameters following so are NULL, that information is not 373 retrieved. 374 @param so The socket to check. 375 @param domain The domain of the socket (PF_INET, etc...). May be NULL. 376 @param type The socket type (SOCK_STREAM, SOCK_DGRAM, etc...). May be NULL. 377 @param protocol The socket protocol. May be NULL. 378 @result 0 on success otherwise the errno error. 379 */ 380errno_t sock_gettype(socket_t so, int *domain, int *type, int *protocol); 381 382#ifdef KERNEL_PRIVATE 383/* 384 @function sock_nointerrupt 385 @discussion Disables interrupt on socket buffers (sets SB_NOINTR on 386 send and receive socket buffers). 387 @param so The socket to modify. 388 @param on Indicate whether or not the SB_NOINTR flag should be set. 389 @result 0 on success otherwise the errno error. 390 */ 391errno_t sock_nointerrupt(socket_t so, int on); 392 393/* 394 @function sock_getlistener 395 @discussion Retrieves the listening socket of a pre-accepted socket, 396 i.e. a socket which is still in the incomplete/completed list. 397 Once a socket has been accepted, the information pertaining 398 to its listener is no longer available. Therefore, modules 399 interested in finding out the listening socket should install 400 the appropriate socket filter callback (sf_attach) which gets 401 invoked prior to the socket being fully accepted, and call 402 this routine at such a time to obtain the listener. Callers 403 are guaranteed that the listener socket will not go away 404 during the sf_attach callback, and therefore the value is 405 safe to be used only in that callback context. Callers should 406 therefore take note that the listening socket's lock will be 407 held throughout the duration of the callback. 408 @param so The pre-accepted socket. 409 @result Non-NULL value which indicates the listening socket; otherwise, 410 NULL if the socket is not in the incomplete/completed list 411 of a listener. 412 */ 413socket_t sock_getlistener(socket_t so); 414 415/* 416 @function sock_getaddr 417 @discussion Retrieves the local or remote address of a socket. 418 This is a composite of sock_getpeername and sock_getsockname, 419 except that the allocated socket address is returned to the 420 caller, and that the caller is reponsible for calling 421 sock_freeaddr once finished with it. 422 @param so The socket. 423 @param psockname Pointer to the storage for the socket name. 424 @param peername 0 for local address, and non-zero for peer address. 425 @result 0 on success otherwise the errno error. 426 */ 427errno_t sock_getaddr(socket_t so, struct sockaddr **psockname, int peername); 428 429/* 430 @function sock_freeaddr 431 @discussion Frees the socket address allocated by sock_getaddr. 432 @param sockname The socket name to be freed. 433 */ 434void sock_freeaddr(struct sockaddr *sockname); 435#endif /* KERNEL_PRIVATE */ 436 437__END_DECLS 438#endif /* __KPI_SOCKET__ */ 439