SystemConfiguration.fproj/SCNetworkConfigurationInternal.c

   1 /*
   2  * Copyright (c) 2004-2007, 2009, 2010-2013, 2015-2018 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*
  25  * Modification History
  26  *
  27  * May 27, 2004         Allan Nathanson <ajn@apple.com>
  28  * - initial revision
  29  */
  30
  31
  32 #include "SCPreferencesInternal.h"
  33 #include "SCNetworkConfigurationInternal.h"
  34
  35 #include <sys/ioctl.h>
  36 #include <net/if.h>
  37
  38
  39 __private_extern__ os_log_t
  40 __log_SCNetworkConfiguration(void)
  41 {
  42         static os_log_t log     = NULL;
  43
  44         if (log == NULL) {
  45                 log = os_log_create("com.apple.SystemConfiguration", "SCNetworkConfiguration");
  46         }
  47
  48         return log;
  49 }
  50
  51
  52 __private_extern__ CFDictionaryRef
  53 __getPrefsConfiguration(SCPreferencesRef prefs, CFStringRef path)
  54 {
  55         CFDictionaryRef config;
  56         CFIndex         n;
  57
  58         config = SCPreferencesPathGetValue(prefs, path);
  59
  60         n = isA_CFDictionary(config) ? CFDictionaryGetCount(config) : 0;
  61         switch (n) {
  62                 case 0 :
  63                         // ignore empty configuration entities
  64                         config = NULL;
  65                         break;
  66                 case 1 :
  67                         if (CFDictionaryContainsKey(config, kSCResvInactive)) {
  68                                 // ignore [effectively] empty configuration entities
  69                                 config = NULL;
  70                         }
  71                         break;
  72                 default :
  73                         break;
  74         }
  75
  76         return config;
  77 }
  78
  79
  80 __private_extern__ Boolean
  81 __setPrefsConfiguration(SCPreferencesRef        prefs,
  82                         CFStringRef             path,
  83                         CFDictionaryRef         config,
  84                         Boolean                 keepInactive)
  85 {
  86         CFDictionaryRef         curConfig;
  87         CFMutableDictionaryRef  newConfig       = NULL;
  88         Boolean                 ok;
  89
  90         if ((config != NULL) && !isA_CFDictionary(config)) {
  91                 _SCErrorSet(kSCStatusInvalidArgument);
  92                 return FALSE;
  93         }
  94
  95         curConfig = SCPreferencesPathGetValue(prefs, path);
  96
  97         if (config != NULL) {
  98                 newConfig = CFDictionaryCreateMutableCopy(NULL, 0, config);
  99         }
 100
 101         if (keepInactive) {
 102                 if (config == NULL) {
 103                         newConfig = CFDictionaryCreateMutable(NULL,
 104                                                               0,
 105                                                               &kCFTypeDictionaryKeyCallBacks,
 106                                                               &kCFTypeDictionaryValueCallBacks);
 107                 }
 108
 109                 if (isA_CFDictionary(curConfig) && CFDictionaryContainsKey(curConfig, kSCResvInactive)) {
 110                         // if currently disabled
 111                         CFDictionarySetValue(newConfig, kSCResvInactive, kCFBooleanTrue);
 112                 } else {
 113                         // if currently enabled
 114                         CFDictionaryRemoveValue(newConfig, kSCResvInactive);
 115                 }
 116         }
 117
 118         // set new configuration
 119         if (_SC_CFEqual(curConfig, newConfig)) {
 120                 // if no change
 121                 if (newConfig != NULL) CFRelease(newConfig);
 122                 ok = TRUE;
 123         } else if (newConfig != NULL) {
 124                 // if new configuration (or we are preserving a disabled state)
 125                 ok = SCPreferencesPathSetValue(prefs, path, newConfig);
 126                 CFRelease(newConfig);
 127         } else {
 128                 ok = SCPreferencesPathRemoveValue(prefs, path);
 129                 if (!ok && (SCError() == kSCStatusNoKey)) {
 130                         ok = TRUE;
 131                 }
 132         }
 133
 134         return ok;
 135 }
 136
 137
 138 __private_extern__ Boolean
 139 __getPrefsEnabled(SCPreferencesRef prefs, CFStringRef path)
 140 {
 141         CFDictionaryRef config;
 142
 143         config = SCPreferencesPathGetValue(prefs, path);
 144         if (isA_CFDictionary(config) && CFDictionaryContainsKey(config, kSCResvInactive)) {
 145                 return FALSE;
 146         }
 147
 148         return TRUE;
 149 }
 150
 151
 152 __private_extern__ Boolean
 153 __setPrefsEnabled(SCPreferencesRef      prefs,
 154                   CFStringRef           path,
 155                   Boolean               enabled)
 156 {
 157         CFDictionaryRef         curConfig;
 158         CFMutableDictionaryRef  newConfig       = NULL;
 159         Boolean                 ok              = FALSE;
 160
 161         // preserve current configuration
 162         curConfig = SCPreferencesPathGetValue(prefs, path);
 163         if (curConfig != NULL) {
 164                 if (!isA_CFDictionary(curConfig)) {
 165                         _SCErrorSet(kSCStatusFailed);
 166                         return FALSE;
 167                 }
 168                 newConfig = CFDictionaryCreateMutableCopy(NULL, 0, curConfig);
 169
 170                 if (enabled) {
 171                         // enable
 172                         CFDictionaryRemoveValue(newConfig, kSCResvInactive);
 173                 } else {
 174                         // disable
 175                         CFDictionarySetValue(newConfig, kSCResvInactive, kCFBooleanTrue);
 176                 }
 177         } else {
 178                 if (!enabled) {
 179                         // disable
 180                         newConfig = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
 181                         CFDictionarySetValue(newConfig, kSCResvInactive, kCFBooleanTrue);
 182                 }
 183         }
 184
 185         // set new configuration
 186         if (_SC_CFEqual(curConfig, newConfig)) {
 187                 // if no change
 188                 if (newConfig != NULL) CFRelease(newConfig);
 189                 ok = TRUE;
 190         } else if (newConfig != NULL) {
 191                 // if updated configuration (or we are establishing as disabled)
 192                 ok = SCPreferencesPathSetValue(prefs, path, newConfig);
 193                 CFRelease(newConfig);
 194         } else {
 195                 ok = SCPreferencesPathRemoveValue(prefs, path);
 196                 if (!ok && (SCError() == kSCStatusNoKey)) {
 197                         ok = TRUE;
 198                 }
 199         }
 200
 201         return ok;
 202 }
 203
 204 #if     TARGET_OS_OSX
 205 #define SYSTEMCONFIGURATION_RESOURCES_PATH      SYSTEMCONFIGURATION_FRAMEWORK_PATH "/Resources"
 206 #else
 207 #define SYSTEMCONFIGURATION_RESOURCES_PATH      SYSTEMCONFIGURATION_FRAMEWORK_PATH
 208 #endif  // TARGET_OS_OSX
 209
 210 #define NETWORKCONFIGURATION_RESOURCE_FILE      "NetworkConfiguration.plist"
 211
 212 static CFDictionaryRef
 213 __copyTemplates()
 214 {
 215         CFBundleRef     bundle;
 216         CFDictionaryRef templates;
 217         CFURLRef        url;
 218
 219         bundle = _SC_CFBundleGet();
 220         if (bundle == NULL) {
 221                 return NULL;
 222         }
 223
 224         url = CFBundleCopyResourceURL(bundle, CFSTR("NetworkConfiguration"), CFSTR("plist"), NULL);
 225         if (url == NULL) {
 226                 SC_log(LOG_ERR, "failed to GET resource URL to \"%s\". Trying harder...", NETWORKCONFIGURATION_RESOURCE_FILE);
 227                 url = CFURLCreateWithFileSystemPath(NULL,
 228                                                     CFSTR(SYSTEMCONFIGURATION_RESOURCES_PATH
 229                                                           "/"
 230                                                           NETWORKCONFIGURATION_RESOURCE_FILE),
 231                                                     kCFURLPOSIXPathStyle,
 232                                                     TRUE);
 233
 234                 if (url == NULL) {
 235                         SC_log(LOG_ERR, "failed to CREATE resource URL to \"%s\"", SYSTEMCONFIGURATION_RESOURCES_PATH
 236                                                                                    "/"
 237                                                                                    NETWORKCONFIGURATION_RESOURCE_FILE);
 238                         return NULL;
 239                 }
 240         }
 241
 242         templates = _SCCreatePropertyListFromResource(url);
 243         CFRelease(url);
 244
 245         if ((templates != NULL) && !isA_CFDictionary(templates)) {
 246                 CFRelease(templates);
 247                 return NULL;
 248         }
 249
 250         return templates;
 251 }
 252
 253
 254 __private_extern__ CFDictionaryRef
 255 __copyInterfaceTemplate(CFStringRef      interfaceType,
 256                         CFStringRef      childInterfaceType)
 257 {
 258         CFDictionaryRef interface       = NULL;
 259         CFDictionaryRef interfaces;
 260         CFDictionaryRef templates;
 261
 262         templates = __copyTemplates();
 263         if (templates == NULL) {
 264                 return NULL;
 265         }
 266
 267         interfaces = CFDictionaryGetValue(templates, CFSTR("Interface"));
 268         if (!isA_CFDictionary(interfaces)) {
 269                 CFRelease(templates);
 270                 return NULL;
 271         }
 272
 273         if (childInterfaceType == NULL) {
 274                 interface = CFDictionaryGetValue(interfaces, interfaceType);
 275         } else {
 276                 CFStringRef     expandedType;
 277
 278                 if (CFStringFind(childInterfaceType, CFSTR("."), 0).location != kCFNotFound) {
 279                         // if "vendor" type
 280                         childInterfaceType = CFSTR("*");
 281                 }
 282
 283                 expandedType = CFStringCreateWithFormat(NULL,
 284                                                         NULL,
 285                                                         CFSTR("%@-%@"),
 286                                                         interfaceType,
 287                                                         childInterfaceType);
 288                 interface = CFDictionaryGetValue(interfaces, expandedType);
 289                 CFRelease(expandedType);
 290         }
 291
 292         if (isA_CFDictionary(interface) && (CFDictionaryGetCount(interface) > 0)) {
 293                 CFRetain(interface);
 294         } else {
 295                 interface = NULL;
 296         }
 297
 298         CFRelease(templates);
 299
 300         return interface;
 301 }
 302
 303
 304 __private_extern__ CFDictionaryRef
 305 __copyProtocolTemplate(CFStringRef      interfaceType,
 306                        CFStringRef      childInterfaceType,
 307                        CFStringRef      protocolType)
 308 {
 309         CFDictionaryRef interface       = NULL;
 310         CFDictionaryRef protocol        = NULL;
 311         CFDictionaryRef protocols;
 312         CFDictionaryRef templates;
 313
 314         templates = __copyTemplates();
 315         if (templates == NULL) {
 316                 return NULL;
 317         }
 318
 319         protocols = CFDictionaryGetValue(templates, CFSTR("Protocol"));
 320         if (!isA_CFDictionary(protocols)) {
 321                 CFRelease(templates);
 322                 return NULL;
 323         }
 324
 325         if (childInterfaceType == NULL) {
 326                 interface = CFDictionaryGetValue(protocols, interfaceType);
 327         } else {
 328                 CFStringRef     expandedType;
 329
 330                 if (CFStringFind(childInterfaceType, CFSTR("."), 0).location != kCFNotFound) {
 331                         // if "vendor" type
 332                         childInterfaceType = CFSTR("*");
 333                 }
 334
 335                 expandedType = CFStringCreateWithFormat(NULL,
 336                                                         NULL,
 337                                                         CFSTR("%@-%@"),
 338                                                         interfaceType,
 339                                                         childInterfaceType);
 340                 interface = CFDictionaryGetValue(protocols, expandedType);
 341                 CFRelease(expandedType);
 342         }
 343
 344         if (isA_CFDictionary(interface)) {
 345                 protocol = CFDictionaryGetValue(interface, protocolType);
 346                 if (isA_CFDictionary(protocol)) {
 347                         CFRetain(protocol);
 348                 } else {
 349                         protocol = NULL;
 350                 }
 351         }
 352
 353         CFRelease(templates);
 354
 355         return protocol;
 356 }
 357
 358
 359 __private_extern__ Boolean
 360 __createInterface(int s, CFStringRef interface)
 361 {
 362         struct ifreq    ifr;
 363
 364         memset(&ifr, 0, sizeof(ifr));
 365         (void) _SC_cfstring_to_cstring(interface,
 366                                        ifr.ifr_name,
 367                                        sizeof(ifr.ifr_name),
 368                                        kCFStringEncodingASCII);
 369
 370         if (ioctl(s, SIOCIFCREATE, &ifr) == -1) {
 371                 SC_log(LOG_NOTICE, "could not create interface \"%@\": %s",
 372                        interface,
 373                        strerror(errno));
 374                 return FALSE;
 375         }
 376
 377         return TRUE;
 378 }
 379
 380
 381 __private_extern__ Boolean
 382 __destroyInterface(int s, CFStringRef interface)
 383 {
 384         struct ifreq    ifr;
 385
 386         memset(&ifr, 0, sizeof(ifr));
 387         (void) _SC_cfstring_to_cstring(interface,
 388                                        ifr.ifr_name,
 389                                        sizeof(ifr.ifr_name),
 390                                        kCFStringEncodingASCII);
 391
 392         if (ioctl(s, SIOCIFDESTROY, &ifr) == -1) {
 393                 SC_log(LOG_NOTICE, "could not destroy interface \"%@\": %s",
 394                        interface,
 395                        strerror(errno));
 396                 return FALSE;
 397         }
 398
 399         return TRUE;
 400 }
 401
 402
 403 /*
 404  * For rdar://problem/4685223
 405  *
 406  * To keep MoreSCF happy we need to ensure that the first "Set" and
 407  * "NetworkService" have a [less than] unique identifier that can
 408  * be parsed as a numeric string.
 409  *
 410  * Note: this backwards compatibility code must be enabled using the
 411  *       following command:
 412  *
 413  *       sudo defaults write                                            \
 414  *              /Library/Preferences/SystemConfiguration/preferences    \
 415  *              MoreSCF                                                 \
 416  *              -bool true
 417  */
 418 __private_extern__
 419 CFStringRef
 420 __SCPreferencesPathCreateUniqueChild_WithMoreSCFCompatibility(SCPreferencesRef prefs, CFStringRef prefix)
 421 {
 422         static int      hack    = -1;
 423         CFStringRef     path    = NULL;
 424
 425         if (hack < 0) {
 426                 CFBooleanRef    enable;
 427
 428                 enable = SCPreferencesGetValue(prefs, CFSTR("MoreSCF"));
 429                 hack = (isA_CFBoolean(enable) && CFBooleanGetValue(enable)) ? 1 : 0;
 430         }
 431
 432         if (hack > 0) {
 433                 CFDictionaryRef dict;
 434                 Boolean ok;
 435
 436                 path = CFStringCreateWithFormat(NULL, NULL, CFSTR("%@/%@"), prefix, CFSTR("0"));
 437                 dict = SCPreferencesPathGetValue(prefs, path);
 438                 if (dict != NULL) {
 439                         // if path "0" exists
 440                         CFRelease(path);
 441                         return NULL;
 442                 }
 443
 444                 // unique child with path "0" does not exist, create
 445                 dict = CFDictionaryCreate(NULL,
 446                                           NULL, NULL, 0,
 447                                           &kCFTypeDictionaryKeyCallBacks,
 448                                           &kCFTypeDictionaryValueCallBacks);
 449                 ok = SCPreferencesPathSetValue(prefs, path, dict);
 450                 CFRelease(dict);
 451                 if (!ok) {
 452                         // if create failed
 453                         CFRelease(path);
 454                         return NULL;
 455                 }
 456         }
 457
 458         return path;
 459 }
 460
 461
 462 static CFDataRef
 463 __copy_legacy_password(CFTypeRef password)
 464 {
 465         if (password == NULL) {
 466                 return NULL;
 467         }
 468
 469         if (isA_CFData(password)) {
 470                 CFIndex n;
 471
 472                 n = CFDataGetLength(password);
 473                 if ((n % sizeof(UniChar)) == 0) {
 474                         CFStringEncoding        encoding;
 475                         CFStringRef             str;
 476
 477 #if     __BIG_ENDIAN__
 478                         encoding = (*(CFDataGetBytePtr(password) + 1) == 0x00) ? kCFStringEncodingUTF16LE : kCFStringEncodingUTF16BE;
 479 #else   // __LITTLE_ENDIAN__
 480                         encoding = (*(CFDataGetBytePtr(password)    ) == 0x00) ? kCFStringEncodingUTF16BE : kCFStringEncodingUTF16LE;
 481 #endif
 482                         str = CFStringCreateWithBytes(NULL,
 483                                                       (const UInt8 *)CFDataGetBytePtr(password),
 484                                                       n,
 485                                                       encoding,
 486                                                       FALSE);
 487                         password = CFStringCreateExternalRepresentation(NULL,
 488                                                                         str,
 489                                                                         kCFStringEncodingUTF8,
 490                                                                         0);
 491                         CFRelease(str);
 492                 } else {
 493                         password = NULL;
 494                 }
 495         } else if (isA_CFString(password) && (CFStringGetLength(password) > 0)) {
 496                 // convert password to CFData
 497                 password = CFStringCreateExternalRepresentation(NULL,
 498                                                                 password,
 499                                                                 kCFStringEncodingUTF8,
 500                                                                 0);
 501         } else {
 502                 password = NULL;
 503         }
 504
 505         return password;
 506 }
 507
 508
 509 __private_extern__
 510 Boolean
 511 __extract_password(SCPreferencesRef     prefs,
 512                    CFDictionaryRef      config,
 513                    CFStringRef          passwordKey,
 514                    CFStringRef          encryptionKey,
 515                    CFStringRef          encryptionKeyChainValue,
 516                    CFStringRef          unique_id,
 517                    CFDataRef            *password)
 518 {
 519         CFStringRef     encryption      = NULL;
 520         Boolean         exists          = FALSE;
 521
 522         // check for keychain password
 523         if (config != NULL) {
 524                 encryption = CFDictionaryGetValue(config, encryptionKey);
 525         }
 526         if ((encryption == NULL) ||
 527             (isA_CFString(encryption) &&
 528              CFEqual(encryption, encryptionKeyChainValue))) {
 529                 // check password
 530                 if (password != NULL) {
 531                         if (prefs != NULL) {
 532                                 *password = _SCPreferencesSystemKeychainPasswordItemCopy(prefs, unique_id);
 533                         } else {
 534                                 *password = _SCSecKeychainPasswordItemCopy(NULL, unique_id);
 535                         }
 536                         exists = (*password != NULL);
 537                 } else {
 538                         if (prefs != NULL) {
 539                                 exists = _SCPreferencesSystemKeychainPasswordItemExists(prefs, unique_id);
 540                         } else {
 541                                 exists = _SCSecKeychainPasswordItemExists(NULL, unique_id);
 542                         }
 543                 }
 544         }
 545
 546         // as needed, check for in-line password
 547         if (!exists && (encryption == NULL) && (config != NULL)) {
 548                 CFDataRef       inline_password;
 549
 550                 inline_password = CFDictionaryGetValue(config, passwordKey);
 551                 inline_password = __copy_legacy_password(inline_password);
 552                 if (inline_password != NULL) {
 553                         exists = TRUE;
 554
 555                         if (password != NULL) {
 556                                 *password = inline_password;
 557                         } else {
 558                                 CFRelease(inline_password);
 559                         }
 560                 }
 561         }
 562
 563         return exists;
 564 }
 565
 566
 567 __private_extern__
 568 Boolean
 569 __remove_password(SCPreferencesRef      prefs,
 570                   CFDictionaryRef       config,
 571                   CFStringRef           passwordKey,
 572                   CFStringRef           encryptionKey,
 573                   CFStringRef           encryptionKeyChainValue,
 574                   CFStringRef           unique_id,
 575                   CFDictionaryRef       *newConfig)
 576 {
 577         CFStringRef             encryption      = NULL;
 578         Boolean                 ok              = FALSE;
 579
 580         // check for keychain password
 581         if (config != NULL) {
 582                 encryption = CFDictionaryGetValue(config, encryptionKey);
 583         }
 584         if ((encryption == NULL) ||
 585             (isA_CFString(encryption) &&
 586              CFEqual(encryption, encryptionKeyChainValue))) {
 587                     // remove keychain password
 588                     if (prefs != NULL) {
 589                             ok = _SCPreferencesSystemKeychainPasswordItemRemove(prefs, unique_id);
 590                     } else {
 591                             ok = _SCSecKeychainPasswordItemRemove(NULL, unique_id);
 592                     }
 593             }
 594
 595         // as needed, check if we have an in-line password that we can remove
 596         if (!ok && (encryption == NULL) && (config != NULL)) {
 597                 CFDataRef       inline_password;
 598
 599                 inline_password = CFDictionaryGetValue(config, passwordKey);
 600                 inline_password = __copy_legacy_password(inline_password);
 601                 if (inline_password != NULL) {
 602                         CFRelease(inline_password);
 603                         ok = TRUE;
 604                 }
 605         }
 606
 607         if (newConfig != NULL) {
 608                 if (ok && (config != NULL)) {
 609                         CFMutableDictionaryRef  temp;
 610
 611                         temp = CFDictionaryCreateMutableCopy(NULL, 0, config);
 612                         CFDictionaryRemoveValue(temp, passwordKey);
 613                         CFDictionaryRemoveValue(temp, encryptionKey);
 614                         *newConfig = (CFDictionaryRef)temp;
 615                 } else {
 616                         *newConfig = NULL;
 617                 }
 618         }
 619
 620         return ok;
 621 }
 622
 623
 624 __private_extern__ Boolean
 625 __rank_to_str(SCNetworkServicePrimaryRank rank, CFStringRef *rankStr)
 626 {
 627         switch (rank) {
 628                 case kSCNetworkServicePrimaryRankDefault :
 629                         *rankStr = NULL;
 630                         break;
 631                 case kSCNetworkServicePrimaryRankFirst :
 632                         *rankStr = kSCValNetServicePrimaryRankFirst;
 633                         break;
 634                 case kSCNetworkServicePrimaryRankLast :
 635                         *rankStr = kSCValNetServicePrimaryRankLast;
 636                         break;
 637                 case kSCNetworkServicePrimaryRankNever :
 638                         *rankStr = kSCValNetServicePrimaryRankNever;
 639                         break;
 640                 case kSCNetworkServicePrimaryRankScoped :
 641                         *rankStr = kSCValNetServicePrimaryRankScoped;
 642                         break;
 643                 default :
 644                         return FALSE;
 645         }
 646
 647         return TRUE;
 648 }
 649
 650
 651 __private_extern__ Boolean
 652 __str_to_rank(CFStringRef rankStr, SCNetworkServicePrimaryRank *rank)
 653 {
 654         if (isA_CFString(rankStr)) {
 655                 if (CFEqual(rankStr, kSCValNetServicePrimaryRankFirst)) {
 656                         *rank = kSCNetworkServicePrimaryRankFirst;
 657                 } else if (CFEqual(rankStr, kSCValNetServicePrimaryRankLast)) {
 658                         *rank = kSCNetworkServicePrimaryRankLast;
 659                 } else if (CFEqual(rankStr, kSCValNetServicePrimaryRankNever)) {
 660                         *rank = kSCNetworkServicePrimaryRankNever;
 661                 } else if (CFEqual(rankStr, kSCValNetServicePrimaryRankScoped)) {
 662                         *rank = kSCNetworkServicePrimaryRankScoped;
 663                 } else {
 664                         return FALSE;
 665                 }
 666         } else if (rankStr == NULL) {
 667                 *rank = kSCNetworkServicePrimaryRankDefault;
 668         } else {
 669                 return FALSE;
 670         }
 671
 672         return TRUE;
 673 }