SystemConfiguration.fproj/SCNetworkConnection.h

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  23
  24 #ifndef _SCNETWORKCONNECTION_H
  25 #ifdef  USE_SYSTEMCONFIGURATION_PRIVATE_HEADERS
  26 #include <SystemConfiguration/_SCNetworkConnection.h>
  27 #else   /* USE_SYSTEMCONFIGURATION_PRIVATE_HEADERS */
  28 #define _SCNETWORKCONNECTION_H
  29
  30 #include <Availability.h>
  31 #include <TargetConditionals.h>
  32 #include <sys/cdefs.h>
  33 #include <dispatch/dispatch.h>
  34 #include <sys/types.h>
  35 #include <sys/socket.h>
  36 #include <CoreFoundation/CoreFoundation.h>
  37 #include <SystemConfiguration/SystemConfiguration.h>
  38
  39
  40 /*!
  41         @header SCNetworkConnection
  42         @discussion The SCNetworkConnection API contains functions that allow
  43                 an application to control connection-oriented services defined
  44                 in the system and get connection-status information.
  45
  46                 The functions in the SCNetworkConnection API allow you to
  47                 control and get information about existing services only.
  48                 If you need to create, change, or remove services, you
  49                 should use the SCNetworkConfiguration API instead.
  50
  51                 Note: Currently, only PPP services can be controlled.
  52  */
  53
  54
  55 /*!
  56         @typedef SCNetworkConnectionRef
  57         @discussion This is the handle to manage a connection-oriented service.
  58  */
  59 typedef const struct __SCNetworkConnection * SCNetworkConnectionRef;
  60
  61
  62 /*!
  63         @typedef SCNetworkConnectionContext
  64         @discussion Structure containing user-specified data and callbacks
  65                 for a SCNetworkConnection.
  66         @field version The version number of the structure type being passed
  67                 in as a parameter to the SCNetworkConnectionCreateWithServiceID
  68                 function.  This structure is version 0.
  69         @field info A C pointer to a user-specified block of data.
  70         @field retain The callback used to add a retain for the info field.
  71                 If this parameter is not a pointer to a function of the correct
  72                 prototype, the behavior is undefined.  The value may be NULL.
  73         @field release The calllback used to remove a retain previously added
  74                 for the info field.  If this parameter is not a pointer to a
  75                 function of the correct prototype, the behavior is undefined.
  76                 The value may be NULL.
  77         @field copyDescription The callback used to provide a description of
  78                 the info field.
  79  */
  80 typedef struct {
  81         CFIndex         version;
  82         void *          info;
  83         const void      *(*retain)(const void *info);
  84         void            (*release)(const void *info);
  85         CFStringRef     (*copyDescription)(const void *info);
  86 } SCNetworkConnectionContext;
  87
  88
  89
  90 /*!
  91         @enum SCNetworkConnectionStatus
  92         @discussion Status of the network connection.
  93                 This status is intended to be generic and high level.
  94                 An extended status, specific to the type of network
  95                 connection is also available for applications that
  96                 need additonal information.
  97         @constant kSCNetworkConnectionInvalid
  98                 The network connection refers to an invalid service.
  99         @constant kSCNetworkConnectionDisconnected
 100                 The network connection is disconnected.
 101         @constant kSCNetworkConnectionConnecting
 102                 The network connection is connecting.
 103         @constant kSCNetworkConnectionConnected
 104                 The network connection is connected.
 105         @constant kSCNetworkConnectionDisconnecting
 106                 The network connection is disconnecting.
 107  */
 108 enum {
 109         kSCNetworkConnectionInvalid             =  -1,
 110         kSCNetworkConnectionDisconnected        =  0,
 111         kSCNetworkConnectionConnecting          =  1,
 112         kSCNetworkConnectionConnected           =  2,
 113         kSCNetworkConnectionDisconnecting       =  3
 114 };
 115 typedef int32_t SCNetworkConnectionStatus;
 116
 117
 118 /*!
 119         @enum SCNetworkConnectionPPPStatus
 120         @discussion PPP-specific status of the network connection.
 121                 This status is returned as part of the extended information
 122                 for a PPP service.
 123                 Note: additional status might be returned in the future.
 124                 Your application should be prepared to receive an unknown value.
 125         @constant kSCNetworkConnectionPPPDisconnected
 126                 PPP is disconnected.
 127         @constant kSCNetworkConnectionPPPInitializing
 128                 PPP is initializing.
 129         @constant kSCNetworkConnectionPPPConnectingLink
 130                 PPP is connecting the lower connection layer (for example,
 131                 the modem is dialing out).
 132         @constant kSCNetworkConnectionPPPDialOnTraffic
 133                 PPP is waiting for networking traffic to automatically
 134                 establish the connection.
 135         @constant kSCNetworkConnectionPPPNegotiatingLink
 136                 The PPP lower layer is connected and PPP is negotiating the
 137                 link layer (LCP protocol).
 138         @constant kSCNetworkConnectionPPPAuthenticating
 139                 PPP is authenticating to the server (PAP, CHAP, MS-CHAP or
 140                 EAP protocols).
 141         @constant kSCNetworkConnectionPPPWaitingForCallBack
 142                 PPP is waiting for the server to call back.
 143         @constant kSCNetworkConnectionPPPNegotiatingNetwork
 144                 PPP is now authenticated and negotiating the networking
 145                 layer (IPCP or IPv6CP protocols)
 146         @constant kSCNetworkConnectionPPPConnected
 147                 PPP is now fully connected for at least one networking layer.
 148                 Additional networking protocol might still be negotiating.
 149         @constant kSCNetworkConnectionPPPTerminating
 150                 PPP networking and link protocols are terminating.
 151         @constant kSCNetworkConnectionPPPDisconnectingLink
 152                 PPP is disconnecting the lower level (for example, the modem
 153                 is hanging up).
 154         @constant kSCNetworkConnectionPPPHoldingLinkOff
 155                 PPP is disconnected and maintaining the link temporarily off.
 156         @constant kSCNetworkConnectionPPPSuspended
 157                 PPP is suspended as a result of the suspend command (for
 158                 example, when a V.92 Modem is On Hold).
 159         @constant kSCNetworkConnectionPPPWaitingForRedial
 160                 PPP has found a busy server and is waiting for redial.
 161  */
 162 enum {
 163         kSCNetworkConnectionPPPDisconnected             =  0,
 164         kSCNetworkConnectionPPPInitializing             =  1,
 165         kSCNetworkConnectionPPPConnectingLink           =  2,
 166         kSCNetworkConnectionPPPDialOnTraffic            =  3,
 167         kSCNetworkConnectionPPPNegotiatingLink          =  4,
 168         kSCNetworkConnectionPPPAuthenticating           =  5,
 169         kSCNetworkConnectionPPPWaitingForCallBack       =  6,
 170         kSCNetworkConnectionPPPNegotiatingNetwork       =  7,
 171         kSCNetworkConnectionPPPConnected                =  8,
 172         kSCNetworkConnectionPPPTerminating              =  9,
 173         kSCNetworkConnectionPPPDisconnectingLink        =  10,
 174         kSCNetworkConnectionPPPHoldingLinkOff           =  11,
 175         kSCNetworkConnectionPPPSuspended                =  12,
 176         kSCNetworkConnectionPPPWaitingForRedial         =  13
 177 };
 178 typedef int32_t SCNetworkConnectionPPPStatus;
 179
 180
 181 /*!
 182         @typedef SCNetworkConnectionCallBack
 183         @discussion Type of the callback function used when a
 184                 status event is delivered.
 185         @param status The connection status.
 186         @param connection The connection reference.
 187         @param info Application-specific information.
 188  */
 189 typedef void (*SCNetworkConnectionCallBack)     (
 190                                                 SCNetworkConnectionRef          connection,
 191                                                 SCNetworkConnectionStatus       status,
 192                                                 void                            *info
 193                                                 );
 194
 195
 196
 197 /*
 198     Keys for the statistics dictionary
 199 */
 200
 201 #define kSCNetworkConnectionBytesIn             CFSTR("BytesIn")                /* CFNumber */
 202 #define kSCNetworkConnectionBytesOut            CFSTR("BytesOut")               /* CFNumber */
 203 #define kSCNetworkConnectionPacketsIn           CFSTR("PacketsIn")              /* CFNumber */
 204 #define kSCNetworkConnectionPacketsOut          CFSTR("PacketsOut")             /* CFNumber */
 205 #define kSCNetworkConnectionErrorsIn            CFSTR("ErrorsIn")               /* CFNumber */
 206 #define kSCNetworkConnectionErrorsOut           CFSTR("ErrorsOut")              /* CFNumber */
 207
 208
 209 /*
 210  Keys for the SCNetworkConnectionCopyUserPreferences() "selectionOptions"
 211  dictionary
 212  */
 213
 214 /*!
 215         @define kSCNetworkConnectionSelectionOptionOnDemandHostName
 216         @discussion A host name that will be used to select the
 217                 "best" SCNetworkConnection.
 218  */
 219 #define kSCNetworkConnectionSelectionOptionOnDemandHostName     CFSTR("OnDemandHostName")       // CFString
 220                                                                                                 // __OSX_AVAILABLE_STARTING(__MAC_10_6,__IPHONE_3_0/*SPI*/)
 221
 222 /*!
 223         @define kSCNetworkConnectionSelectionOptionOnDemandRetry
 224         @discussion A boolean value used to indicate whether a DNS query has
 225                 already been issued for the specified OnDemand host name.
 226  */
 227 #define kSCNetworkConnectionSelectionOptionOnDemandRetry        CFSTR("OnDemandRetry")          // CFBoolean
 228                                                                                                 // __OSX_AVAILABLE_STARTING(__MAC_10_6,__IPHONE_3_0/*SPI*/)
 229
 230 __BEGIN_DECLS
 231
 232 /*!
 233         @function SCNetworkConnectionGetTypeID
 234         @discussion Returns the type identifier of all SCNetworkConnection
 235                 instances.
 236  */
 237 CFTypeID
 238 SCNetworkConnectionGetTypeID                    (void)                  __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 239
 240
 241 /*!
 242         @function SCNetworkConnectionCopyUserPreferences
 243         @discussion Provides the default service ID and a dictionary of user
 244                 options for the connection.  Applications can use the
 245                 returned serviceID and userOptions values to open a
 246                 connection on the fly.
 247         @param selectionOptions Currently unimplemented. Pass NULL for this
 248                 version.
 249         @param serviceID Reference to the default serviceID for starting
 250                 connections, this value will be returned by the function.
 251         @param userOptions Reference to default userOptions for starting
 252                 connections, this will be returned by the function.
 253         @result Returns TRUE if there is a valid service to dial;
 254                 FALSE if the function was unable to retrieve a service to dial.
 255  */
 256 Boolean
 257 SCNetworkConnectionCopyUserPreferences          (
 258                                                 CFDictionaryRef                 selectionOptions,
 259                                                 CFStringRef                     *serviceID,
 260                                                 CFDictionaryRef                 *userOptions
 261                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 262
 263
 264 /*!
 265         @function SCNetworkConnectionCreateWithServiceID
 266         @discussion Creates a new connection reference to use for getting
 267                 the status or for connecting or disconnecting the associated
 268                 service.
 269         @param allocator The CFAllocator that should be used to allocate
 270                 memory for the connection structure.  This parameter may be
 271                 NULL in which case the current default CFAllocator is used.
 272                 If this reference is not a valid CFAllocator, the behavior
 273                 is undefined.
 274         @param serviceID A string that defines the service identifier
 275                 of the connection.  Service identifiers uniquely identify
 276                 services in the system configuration database.
 277         @param callout The function to be called when the status
 278                 of the connection changes.  If this parameter is NULL, the
 279                 application will not receive notifications of status change
 280                 and will need to poll for updates.
 281         @param context The SCNetworkConnectionContext associated with the
 282                 callout.
 283         @result Returns a reference to the new SCNetworkConnection.
 284  */
 285 SCNetworkConnectionRef
 286 SCNetworkConnectionCreateWithServiceID          (
 287                                                 CFAllocatorRef                  allocator,
 288                                                 CFStringRef                     serviceID,
 289                                                 SCNetworkConnectionCallBack     callout,
 290                                                 SCNetworkConnectionContext      *context
 291                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 292
 293
 294 /*!
 295         @function SCNetworkConnectionCopyServiceID
 296         @discussion Returns the service ID associated with the SCNetworkConnection.
 297         @param connection The SCNetworkConnection to obtain status from.
 298         @result Returns the service ID associated with the SCNetworkConnection.
 299  */
 300 CFStringRef
 301 SCNetworkConnectionCopyServiceID                (
 302                                                 SCNetworkConnectionRef          connection
 303                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 304
 305
 306 /*!
 307         @function SCNetworkConnectionGetStatus
 308         @discussion Returns the status of the SCNetworkConnection.
 309                 A status is one of the following values:
 310 <pre>
 311 @textblock
 312 &#32
 313         kSCNetworkConnectionInvalid
 314         kSCNetworkConnectionDisconnected
 315         kSCNetworkConnectionConnecting
 316         kSCNetworkConnectionDisconnecting
 317         kSCNetworkConnectionConnected
 318 @/textblock
 319 </pre>
 320         @param connection The SCNetworkConnection to obtain status from.
 321         @result Returns the status value.
 322 */
 323 SCNetworkConnectionStatus
 324 SCNetworkConnectionGetStatus                    (
 325                                                 SCNetworkConnectionRef          connection
 326                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 327
 328
 329 /*!
 330         @function SCNetworkConnectionCopyExtendedStatus
 331         @discussion Returns the extended status of the connection.
 332                 An extended status dictionary contains specific dictionaries
 333                 describing the status for each subcomponent of the service.
 334
 335                 For example, a status dictionary will contain the following
 336                 sub-dictionaries, keys, and values:
 337 <pre>
 338 @textblock
 339 &#32
 340         IPv4  : Addresses      : the assigned IP address.
 341 &#32
 342         PPP   : Status         : the PPP-specific status of type
 343                                  SCNetworkConnectionPPPStatus.
 344 &#32
 345                 LastCause      : Available when the status is "Disconnected"
 346                                  and contains the last error associated with
 347                                  connecting or disconnecting.
 348 &#32
 349                 ConnectTime    : the time when the connection was
 350                                  established.
 351 &#32
 352         Modem : ConnectSpeed   : the speed of the modem connection
 353                                  in bits/second.
 354 &#32
 355         IPSec : Status         : the IPSec-specific status of type
 356                                  SCNetworkConnectionIPSecStatus
 357 &#32
 358                 ConnectTime    : the time when the connection was
 359                                  established.
 360
 361 @/textblock
 362 </pre>
 363                 Other dictionaries could be present for PPPoE, PPTP, and L2TP.
 364
 365                 The status dictionary may be extended in the future to contain
 366                 additional information.
 367         @param connection The SCNetworkConnection to obtain status from.
 368         @result Returns the status dictionary.
 369                 If NULL is returned, the error can be retrieved using the SCError function.
 370  */
 371 CFDictionaryRef
 372 SCNetworkConnectionCopyExtendedStatus           (
 373                                                 SCNetworkConnectionRef          connection
 374                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 375
 376
 377 /*!
 378         @function SCNetworkConnectionCopyStatistics
 379         @discussion Returns the statistics of the SCNetworkConnection.
 380                 A statistic dictionary contains specific dictionaries
 381                 with statistics for each subcomponent of the service.
 382
 383                 For example, a statistics dictionary will contain the following
 384                 sub-dictionaries, keys, and values:
 385 <pre>
 386 @textblock
 387 &#32
 388         PPP : BytesIn    :
 389         PPP : BytesOut   : Contains the number of bytes going up into
 390                            (or coming out of) the network stack for
 391                            any networking protocol without the PPP
 392                            headers and trailers.
 393 &#32
 394         PPP : PacketsIn  :
 395         PPP : PacketsOut : Contains the number of packets going up into
 396                            (or coming out of) the network stack for
 397                            any networking protocol without the PPP
 398                            headers and trailers.
 399 &#32
 400         PPP : ErrorsIn   :
 401         PPP : ErrorsOut  : Contains the number of errors going up into
 402                            (or coming out of) the network stack for
 403                            any networking protocol without the PPP
 404                            headers and trailers.
 405 @/textblock
 406 </pre>
 407                 The statistics dictionary may be extended in the future to
 408                 contain additional information.
 409         @param connection The SCNetworkConnection to obtained statistics from.
 410         @result Returns the statistics dictionary.
 411                 If NULL is returned, the error can be retrieved using the SCError function.
 412  */
 413 CFDictionaryRef
 414 SCNetworkConnectionCopyStatistics               (
 415                                                 SCNetworkConnectionRef          connection
 416                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 417
 418
 419 /*!
 420         @function SCNetworkConnectionStart
 421         @discussion Starts the connection for the SCNetworkConnection.
 422                 The connection process is asynchronous and the function will
 423                 return immediately.  The connection status can be obtained
 424                 by polling or by callback.  The connection is made with the
 425                 default settings from the administrator.  Some of the settings
 426                 can be overridden for the duration of the connection.  These
 427                 are specified in an options dictionary.  The options dictionary
 428                 uses the same format as a network service defined in the system
 429                 configuration preferences schema.
 430
 431                 Note: Starting and stopping of connections is implicitly
 432                 arbitrated.  Calling SCNetworkConnectionStart on a connection
 433                 already started will indicate that the application has
 434                 interest in the connection and it shouldn't be stopped by
 435                 anyone else.
 436         @param connection The SCNetworkConnection to start.
 437         @param userOptions The options dictionary to start the connection with.
 438                 If userOptions is NULL, the default settings will be used.
 439                 If userOptions are specified, they must be in the same format
 440                 as network services stored in the system configuration
 441                 preferences schema.  The options will override the default
 442                 settings defined for the service.
 443
 444                 For security reasons, not all options can be overridden; the
 445                 appropriate merging of all settings will be done before the
 446                 connection is established, and inappropriate options will be
 447                 ignored.
 448         @param linger This parameter indicates whether or not the connection
 449                 can stay around when the application no longer has interest
 450                 in it.  A typical application should pass FALSE, and the
 451                 connection will be automatically stopped when the reference
 452                 is released or if the application quits.  If the application
 453                 passes TRUE, the application can release the reference or
 454                 exit and the connection will be maintained until a timeout
 455                 event, until a specific stop request occurs, or until an
 456                 error is encountered.
 457         @result Returns TRUE if the connection was correctly started (the
 458                 actual connection is not established yet, and the connection
 459                 status needs to be periodically checked); FALSE if the
 460                 connection request was not started.  The error must be
 461                 retrieved from the SCError function.
 462  */
 463 Boolean
 464 SCNetworkConnectionStart                        (
 465                                                 SCNetworkConnectionRef          connection,
 466                                                 CFDictionaryRef                 userOptions,
 467                                                 Boolean                         linger
 468                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 469
 470
 471 /*!
 472         @function SCNetworkConnectionStop
 473         @discussion Stops the connection for the SCNetworkConnection.
 474                 The disconnection process is asynchronous and the function
 475                 will return immediately.  The connection status can be
 476                 obtained by polling or by callback.  This function performs
 477                 an arbitrated stop of the connection.  If several applications
 478                 have marked their interest in the connection, by calling
 479                 SCNetworkConnectionStart, the call will succeed but the
 480                 actual connection will be maintained until the last interested
 481                 application calls SCNetworkConnectionStop.
 482
 483                 In certain cases, you might want to stop the connection anyway.
 484                 In these cases, you set the forceDisconnect argument to TRUE.
 485         @param connection The SCNetworkConnection to stop.
 486         @result Returns TRUE if the disconnection request succeeded;
 487                 FALSE if the disconnection request failed.
 488                 The error must be retrieved from the SCError function.
 489  */
 490 Boolean
 491 SCNetworkConnectionStop                         (
 492                                                 SCNetworkConnectionRef          connection,
 493                                                 Boolean                         forceDisconnect
 494                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 495
 496
 497 /*!
 498         @function SCNetworkConnectionCopyUserOptions
 499         @discussion Copies the user options used to start the connection.
 500                 This is a mechanism a client can use to retrieve the user options
 501                 previously passed to the SCNetworkConnectionStart function.
 502         @param connection The SCNetworkConnection to obtain options from.
 503         @result Returns the service dictionary containing the connection options.
 504                 The dictionary can be empty if no user options were used.
 505                 If NULL is returned, the error can be retrieved using the SCError function.
 506  */
 507 CFDictionaryRef
 508 SCNetworkConnectionCopyUserOptions              (
 509                                                 SCNetworkConnectionRef          connection
 510                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 511
 512
 513 /*!
 514         @function SCNetworkConnectionScheduleWithRunLoop
 515         @discussion Schedules a connection with the run loop.
 516         @param connection The SCNetworkConnection to schedule.
 517         @param runLoop The run loop to schedule with.
 518         @param runLoopMode The run loop mode.
 519         @result Returns TRUE if the connection is scheduled successfully;
 520                 FALSE if the scheduling failed.
 521                 The error can be retrieved using the SCError function.
 522  */
 523 Boolean
 524 SCNetworkConnectionScheduleWithRunLoop          (
 525                                                 SCNetworkConnectionRef          connection,
 526                                                 CFRunLoopRef                    runLoop,
 527                                                 CFStringRef                     runLoopMode
 528                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 529
 530
 531 /*!
 532         @function SCNetworkConnectionUnscheduleFromRunLoop
 533         @discussion Unschedules a connection from the run loop.
 534         @param connection The SCNetworkConnection to unschedule.
 535         @param runLoop The run loop to unschedule from.
 536         @param runLoopMode The run loop mode.
 537         @result Returns TRUE if the connection is unscheduled successfully;
 538                 FALSE if the unscheduling failed.
 539                 The error can be retrieved using the SCError function.
 540  */
 541 Boolean
 542 SCNetworkConnectionUnscheduleFromRunLoop        (
 543                                                 SCNetworkConnectionRef          connection,
 544                                                 CFRunLoopRef                    runLoop,
 545                                                 CFStringRef                     runLoopMode
 546                                                 )                       __OSX_AVAILABLE_STARTING(__MAC_10_3,__IPHONE_2_0/*SPI*/);
 547
 548
 549 /*!
 550          @function SCNetworkConnectionSetDispatchQueue
 551          @discussion Caller provides a dispatch queue on which the callback contained in connection will run.
 552          @param connection The SCNetworkConnection to notify.
 553          @param queue The libdispatch queue to run the callback on.
 554                 Pass NULL to disable notifications, and release queue.
 555          @result Returns TRUE if the notifications have been enabled/disabled as desired;
 556                  FALSE if not.
 557                  The error can be retrieved using the SCError function.
 558  */
 559 Boolean
 560 SCNetworkConnectionSetDispatchQueue             (
 561                                                  SCNetworkConnectionRef         connection,
 562                                                  dispatch_queue_t               queue
 563                                                  )                      __OSX_AVAILABLE_STARTING(__MAC_10_6,__IPHONE_4_0/*SPI*/);
 564
 565 __END_DECLS
 566
 567 #endif  /* USE_SYSTEMCONFIGURATION_PRIVATE_HEADERS */
 568 #endif /* _SCNETWORKCONNECTION_H */