OSX/sec/SOSCircle/SecureObjectSync/SOSViews.c

   1 /*
   2  * Copyright (c) 2015 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  * SOSViews.c -  Implementation of views
  26  */
  27
  28 #include <AssertMacros.h>
  29 #include <TargetConditionals.h>
  30
  31 #include "SOSViews.h"
  32 #include <utilities/SecCFWrappers.h>
  33 #include <utilities/SecCFRelease.h>
  34 #include <utilities/SecXPCError.h>
  35
  36 #include <utilities/SecCFError.h>
  37 #include <utilities/der_set.h>
  38 #include <Security/SecureObjectSync/SOSInternal.h>
  39
  40 #include <Security/SecureObjectSync/SOSPeerInfo.h>
  41 #include <Security/SecureObjectSync/SOSPeerInfoV2.h>
  42 #include <Security/SecureObjectSync/SOSPeerInfoPriv.h>
  43 #include <Security/SecureObjectSync/SOSCloudCircle.h>
  44 #include <Security/SecureObjectSync/SOSAccount.h>
  45 #include <Security/SecureObjectSync/SOSAccountPriv.h>
  46
  47 CFStringRef viewMemError                = CFSTR("Failed to get memory for views in PeerInfo");
  48 CFStringRef viewUnknownError            = CFSTR("Unknown view(%@) (ViewResultCode=%d)");
  49 CFStringRef viewInvalidError            = CFSTR("Peer is invalid for this view(%@) (ViewResultCode=%d)");
  50
  51 // Internal Views:
  52 const CFStringRef kSOSViewKeychainV0_tomb           = CFSTR("KeychainV0-tomb"); // iCloud Keychain backup for v0 peers (no tombstones)
  53 const CFStringRef kSOSViewBackupBagV0_tomb          = CFSTR("BackupBagV0-tomb");     // iCloud Keychain backup bag for v0 peers (no tombstones)
  54 const CFStringRef kSOSViewWiFi_tomb                 = CFSTR("WiFi-tomb");
  55 const CFStringRef kSOSViewAutofillPasswords_tomb    = CFSTR("Passwords-tomb");
  56 const CFStringRef kSOSViewSafariCreditCards_tomb    = CFSTR("CreditCards-tomb");
  57 const CFStringRef kSOSViewiCloudIdentity_tomb       = CFSTR("iCloudIdentity-tomb");
  58 const CFStringRef kSOSViewOtherSyncable_tomb        = CFSTR("OtherSyncable-tomb");
  59
  60 // Views
  61 const CFStringRef kSOSViewKeychainV0            = CFSTR("KeychainV0");      // iCloud Keychain syncing for v0 peers
  62
  63 #undef DOVIEWMACRO
  64 #define DOVIEWMACRO(VIEWNAME, DEFSTRING, CMDSTRING, DEFAULTSETTING, INITIALSYNCSETTING, ALWAYSONSETTING, BACKUPSETTING, V0SETTING) \
  65 const CFStringRef kSOSView##VIEWNAME          = CFSTR(DEFSTRING);
  66 #include "Security/SecureObjectSync/ViewList.list"
  67
  68 // View Hints
  69 // Note that by definition, there cannot be a V0 view hint
  70 // These will be deprecated for new constants found in SecItemPriv.h
  71 const CFStringRef kSOSViewHintPCSMasterKey      = CFSTR("PCS-MasterKey");
  72 const CFStringRef kSOSViewHintPCSiCloudDrive    = CFSTR("PCS-iCloudDrive");
  73 const CFStringRef kSOSViewHintPCSPhotos         = CFSTR("PCS-Photos");
  74 const CFStringRef kSOSViewHintPCSCloudKit       = CFSTR("PCS-CloudKit");
  75 const CFStringRef kSOSViewHintPCSEscrow         = CFSTR("PCS-Escrow");
  76 const CFStringRef kSOSViewHintPCSFDE            = CFSTR("PCS-FDE");
  77 const CFStringRef kSOSViewHintPCSMailDrop       = CFSTR("PCS-Maildrop");
  78 const CFStringRef kSOSViewHintPCSiCloudBackup   = CFSTR("PCS-Backup");
  79 const CFStringRef kSOSViewHintPCSNotes          = CFSTR("PCS-Notes");
  80 const CFStringRef kSOSViewHintPCSiMessage       = CFSTR("PCS-iMessage");
  81 const CFStringRef kSOSViewHintPCSFeldspar       = CFSTR("PCS-Feldspar");
  82
  83 const CFStringRef kSOSViewHintAppleTV           = CFSTR("AppleTV");
  84 const CFStringRef kSOSViewHintHomeKit           = CFSTR("HomeKit");
  85
  86 CFMutableSetRef SOSViewCopyViewSet(ViewSetKind setKind) {
  87     CFMutableSetRef result = CFSetCreateMutableForCFTypes(kCFAllocatorDefault);
  88
  89 #undef DOVIEWMACRO
  90 #define __TYPE_MEMBER_ false
  91 #define __TYPE_MEMBER_D true
  92 #define __TYPE_MEMBER_I true
  93 #define __TYPE_MEMBER_A true
  94 #define __TYPE_MEMBER_V true
  95 #define __TYPE_MEMBER_B true
  96 #define DOVIEWMACRO(VIEWNAME, DEFSTRING, CMDSTRING, DEFAULT, INITIAL, ALWAYSON, BACKUP, V0) \
  97     if ((setKind == kViewSetAll) || \
  98        ((setKind == kViewSetDefault)   && __TYPE_MEMBER_##DEFAULT)  || \
  99        ((setKind == kViewSetInitial)   && __TYPE_MEMBER_##INITIAL)  || \
 100        ((setKind == kViewSetAlwaysOn)  && __TYPE_MEMBER_##ALWAYSON) || \
 101        ((setKind == kViewSetRequiredForBackup)  && __TYPE_MEMBER_##BACKUP) || \
 102        ((setKind == kViewSetV0)  && __TYPE_MEMBER_##V0)       ) { \
 103            CFSetAddValue(result, kSOSView##VIEWNAME); \
 104     }
 105
 106 #include "Security/SecureObjectSync/ViewList.list"
 107
 108     return result;
 109 }
 110
 111 CFGiblisGetSingleton(CFSetRef, SOSViewsGetV0ViewSet, defaultViewSet, ^{
 112     // Since peer->views must never be NULL, fill in with a default
 113     const void *values[] = { kSOSViewKeychainV0 };
 114     *defaultViewSet = CFSetCreate(kCFAllocatorDefault, values, array_size(values), &kCFTypeSetCallBacks);
 115 });
 116
 117 CFGiblisGetSingleton(CFSetRef, SOSViewsGetV0SubviewSet, subViewSet, (^{
 118     // Since peer->views must never be NULL, fill in with a default
 119     *subViewSet = SOSViewCopyViewSet(kViewSetV0);
 120 }));
 121
 122 CFGiblisGetSingleton(CFSetRef, SOSViewsGetV0BackupViewSet, defaultViewSet, ^{
 123     const void *values[] = { kSOSViewKeychainV0_tomb };
 124     *defaultViewSet = CFSetCreate(kCFAllocatorDefault, values, array_size(values), &kCFTypeSetCallBacks);
 125 });
 126
 127 CFGiblisGetSingleton(CFSetRef, SOSViewsGetV0BackupBagViewSet, defaultViewSet, ^{
 128     const void *values[] = { kSOSViewBackupBagV0_tomb };
 129     *defaultViewSet = CFSetCreate(kCFAllocatorDefault, values, array_size(values), &kCFTypeSetCallBacks);
 130 });
 131
 132
 133 CFGiblisGetSingleton(CFSetRef, SOSViewsGetInitialSyncSubviewSet, subViewSet, (^{
 134     *subViewSet = SOSViewCopyViewSet(kViewSetInitial);
 135 }));
 136
 137
 138 bool SOSViewsIsV0Subview(CFStringRef viewName) {
 139     return CFSetContainsValue(SOSViewsGetV0SubviewSet(), viewName);
 140 }
 141
 142 CFSetRef sTestViewSet = NULL;
 143 void SOSViewsSetTestViewsSet(CFSetRef testViewNames) {
 144     CFRetainAssign(sTestViewSet, testViewNames);
 145 }
 146
 147 CFSetRef SOSViewsGetAllCurrent(void) {
 148     static dispatch_once_t dot;
 149     static CFMutableSetRef allViews = NULL;
 150     dispatch_once(&dot, ^{
 151         allViews = SOSViewCopyViewSet(kViewSetAll);
 152
 153         CFSetAddValue(allViews, kSOSViewKeychainV0);
 154         if(sTestViewSet) CFSetUnion(allViews, sTestViewSet);
 155     });
 156     return allViews;
 157 }
 158
 159 const char *SOSViewsXlateAction(SOSViewActionCode action) {
 160     switch(action) {
 161         case kSOSCCViewEnable: return "kSOSCCViewEnable";
 162         case kSOSCCViewDisable: return "kSOSCCViewDisable";
 163         case kSOSCCViewQuery: return "kSOSCCViewQuery";
 164         default: return "unknownViewAction";
 165     }
 166 }
 167
 168
 169 // Eventually this will want to know the gestalt or security properties...
 170 void SOSViewsForEachDefaultEnabledViewName(void (^operation)(CFStringRef viewName)) {
 171     CFMutableSetRef defaultViews = SOSViewCopyViewSet(kViewSetDefault);
 172
 173     CFSetForEach(defaultViews, ^(const void *value) {
 174         CFStringRef name = asString(value, NULL);
 175
 176         if (name) {
 177             operation(name);
 178         }
 179     });
 180
 181     CFReleaseNull(defaultViews);
 182 }
 183
 184 static bool SOSViewsIsKnownView(CFStringRef viewname) {
 185     CFSetRef allViews = SOSViewsGetAllCurrent();
 186     if(CFSetContainsValue(allViews, viewname)) return true;
 187     secnotice("views","Not a known view");
 188     return false;
 189 }
 190
 191 static bool viewErrorReport(CFIndex errorCode, CFErrorRef *error, CFStringRef format, CFStringRef viewname, int retval) {
 192     return SOSCreateErrorWithFormat(errorCode, NULL, error, NULL, format, viewname, retval);
 193 }
 194
 195 static bool SOSViewsRequireIsKnownView(CFStringRef viewname, CFErrorRef* error) {
 196     return SOSViewsIsKnownView(viewname) || viewErrorReport(kSOSErrorNameMismatch, error, viewUnknownError, viewname, kSOSCCNoSuchView);
 197 }
 198
 199 bool SOSPeerInfoIsEnabledView(SOSPeerInfoRef pi, CFStringRef viewName) {
 200     if (pi->version < kSOSPeerV2BaseVersion) {
 201         return CFSetContainsValue(SOSViewsGetV0ViewSet(), viewName);
 202     } else {
 203         return SOSPeerInfoV2DictionaryHasSetContaining(pi, sViewsKey, viewName);
 204     }
 205 }
 206
 207 void SOSPeerInfoWithEnabledViewSet(SOSPeerInfoRef pi, void (^operation)(CFSetRef enabled)) {
 208     if (pi->version < kSOSPeerV2BaseVersion) {
 209         operation(SOSViewsGetV0ViewSet());
 210     } else {
 211         SOSPeerInfoV2DictionaryWithSet(pi, sViewsKey, operation);
 212     }
 213 }
 214
 215 CFMutableSetRef SOSPeerInfoCopyEnabledViews(SOSPeerInfoRef pi) {
 216     if (pi->version < kSOSPeerV2BaseVersion) {
 217         return CFSetCreateMutableCopy(kCFAllocatorDefault, CFSetGetCount(SOSViewsGetV0ViewSet()), SOSViewsGetV0ViewSet());
 218     } else {
 219         CFMutableSetRef views = SOSPeerInfoV2DictionaryCopySet(pi, sViewsKey);
 220         if (!views) {
 221             // This is unexpected: log and return an empty set to prevent <rdar://problem/21938868>
 222             secerror("%@ v2 peer has no views", SOSPeerInfoGetPeerID(pi));
 223             views = CFSetCreateMutableForCFTypes(kCFAllocatorDefault);
 224         }
 225         return views;
 226     }
 227 }
 228
 229 CFSetRef SOSPeerInfoGetPermittedViews(SOSPeerInfoRef pi) {
 230     return SOSViewsGetAllCurrent();
 231 }
 232
 233 static void SOSPeerInfoSetViews(SOSPeerInfoRef pi, CFSetRef newviews) {
 234     if(!newviews) {
 235         secnotice("views","Asked to swap to NULL views");
 236         return;
 237     }
 238     SOSPeerInfoV2DictionarySetValue(pi, sViewsKey, newviews);
 239 }
 240
 241 static bool SOSPeerInfoViewIsValid(SOSPeerInfoRef pi, CFStringRef viewname) {
 242     return true;
 243 }
 244
 245 SOSViewResultCode SOSViewsEnable(SOSPeerInfoRef pi, CFStringRef viewname, CFErrorRef *error) {
 246     SOSViewResultCode retval = kSOSCCGeneralViewError;
 247
 248     CFMutableSetRef newviews = SOSPeerInfoCopyEnabledViews(pi);
 249     require_action_quiet(newviews, fail,
 250                          SOSCreateError(kSOSErrorAllocationFailure, viewMemError, NULL, error));
 251     require_action_quiet(SOSViewsRequireIsKnownView(viewname, error), fail,
 252                          retval = kSOSCCNoSuchView);
 253     require_action_quiet(SOSPeerInfoViewIsValid(pi, viewname), fail,
 254                          viewErrorReport(kSOSErrorNameMismatch, error, viewInvalidError, viewname, retval = kSOSCCViewNotQualified));
 255     CFSetAddValue(newviews, viewname);
 256     SOSPeerInfoSetViews(pi, newviews);
 257     CFReleaseSafe(newviews);
 258     return kSOSCCViewMember;
 259
 260 fail:
 261     CFReleaseNull(newviews);
 262     secnotice("views","Failed to enable view(%@): %@", viewname, error ? *error : NULL);
 263     return retval;
 264 }
 265
 266 bool SOSViewSetEnable(SOSPeerInfoRef pi, CFSetRef viewSet) {
 267     __block bool addedView = false;
 268     CFMutableSetRef newviews = SOSPeerInfoCopyEnabledViews(pi);
 269     require_action_quiet(newviews, errOut, secnotice("views", "failed to copy enabled views"));
 270
 271     CFSetForEach(viewSet, ^(const void *value) {
 272         CFStringRef viewName = (CFStringRef) value;
 273         if(SOSViewsIsKnownView(viewName) && SOSPeerInfoViewIsValid(pi, viewName)) {
 274             if (!CFSetContainsValue(newviews, viewName)) {
 275                 addedView = true;
 276                 CFSetAddValue(newviews, viewName);
 277             }
 278         } else {
 279             secnotice("views", "couldn't add view %@", viewName);
 280         }
 281     });
 282     require_quiet(addedView, errOut);
 283
 284     SOSPeerInfoSetViews(pi, newviews);
 285
 286 errOut:
 287     CFReleaseNull(newviews);
 288     return addedView;
 289 }
 290
 291
 292 SOSViewResultCode SOSViewsDisable(SOSPeerInfoRef pi, CFStringRef viewname, CFErrorRef *error) {
 293     SOSViewResultCode retval = kSOSCCGeneralViewError;
 294     CFMutableSetRef newviews = SOSPeerInfoCopyEnabledViews(pi);
 295     require_action_quiet(newviews, fail,
 296                          SOSCreateError(kSOSErrorAllocationFailure, viewMemError, NULL, error));
 297     require_action_quiet(SOSViewsRequireIsKnownView(viewname, error), fail, retval = kSOSCCNoSuchView);
 298
 299     CFSetRemoveValue(newviews, viewname);
 300     SOSPeerInfoSetViews(pi, newviews);
 301     CFReleaseSafe(newviews);
 302     return kSOSCCViewNotMember;
 303
 304 fail:
 305     CFReleaseNull(newviews);
 306     secnotice("views","Failed to disable view(%@): %@", viewname, error ? *error : NULL);
 307     return retval;
 308 }
 309
 310
 311 bool SOSViewSetDisable(SOSPeerInfoRef pi, CFSetRef viewSet) {
 312     __block bool removed = false;
 313     CFMutableSetRef newviews = SOSPeerInfoCopyEnabledViews(pi);
 314     require_action_quiet(newviews, errOut, secnotice("views", "failed to copy enabled views"));
 315
 316     CFSetForEach(viewSet, ^(const void *value) {
 317         CFStringRef viewName = (CFStringRef) value;
 318         if(SOSViewsIsKnownView(viewName) && CFSetContainsValue(newviews, viewName)) {
 319             removed = true;
 320             CFSetRemoveValue(newviews, viewName);
 321         } else {
 322             secnotice("views", "couldn't delete view %@", viewName);
 323         }
 324     });
 325
 326     require_quiet(removed, errOut);
 327
 328     SOSPeerInfoSetViews(pi, newviews);
 329
 330 errOut:
 331     CFReleaseNull(newviews);
 332     return removed;
 333 }
 334
 335
 336 SOSViewResultCode SOSViewsQuery(SOSPeerInfoRef pi, CFStringRef viewname, CFErrorRef *error) {
 337     SOSViewResultCode retval = kSOSCCNoSuchView;
 338     CFSetRef views = NULL;
 339     require_quiet(SOSViewsRequireIsKnownView(viewname, error), fail);
 340
 341     views = SOSPeerInfoCopyEnabledViews(pi);
 342     if(!views){
 343         retval = kSOSCCViewNotMember;
 344         CFReleaseNull(views);
 345         return retval;
 346     }
 347
 348     // kSOSViewKeychainV0 is set if there is a V0 PeerInfo in the circle.  It represents all of the subviews in
 349     // SOSViewsGetV0SubviewSet() so we return kSOSCCViewMember for that case.  kSOSViewKeychainV0 and the subviews
 350     // are mutually exclusive.
 351     else if(CFSetContainsValue(views, kSOSViewKeychainV0) && CFSetContainsValue(SOSViewsGetV0SubviewSet(), viewname)) {
 352         retval = kSOSCCViewMember;
 353     } else {
 354         retval = (CFSetContainsValue(views, viewname)) ? kSOSCCViewMember: kSOSCCViewNotMember;
 355     }
 356
 357     CFReleaseNull(views);
 358     return retval;
 359
 360 fail:
 361     secnotice("views","Failed to query view(%@): %@", viewname, error ? *error : NULL);
 362     CFReleaseNull(views);
 363     return retval;
 364 }
 365
 366 static CFArrayRef SOSCreateActiveViewIntersectionArrayForPeerInfos(SOSPeerInfoRef pi1, SOSPeerInfoRef pi2) {
 367     CFMutableArrayRef  retval = NULL;
 368     CFSetRef views1 = SOSPeerInfoCopyEnabledViews(pi1);
 369     CFSetRef views2 = SOSPeerInfoCopyEnabledViews(pi2);
 370     size_t count = CFSetGetCount(views1);
 371     if(count == 0){
 372         CFReleaseNull(views1);
 373         CFReleaseNull(views2);
 374         return NULL;
 375     }
 376     CFStringRef pi1views[count];
 377
 378     retval = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
 379     CFSetGetValues(views1, (const void **) &pi1views);
 380     for(size_t i = 0; i < count; i++) {
 381         if(CFSetContainsValue(views2, pi1views[i])) {
 382             CFArrayAppendValue(retval, pi1views[i]);
 383         }
 384     }
 385     CFReleaseNull(views1);
 386     CFReleaseNull(views2);
 387
 388     return retval;
 389 }
 390
 391 CFArrayRef SOSCreateActiveViewIntersectionArrayForPeerID(SOSAccountRef account, CFStringRef peerID) {
 392     CFArrayRef  retval = NULL;
 393     SOSPeerInfoRef myPI = SOSAccountGetMyPeerInfo(account);
 394     SOSPeerInfoRef theirPI = SOSAccountCopyPeerWithID(account, peerID, NULL);
 395     require_action_quiet(myPI, errOut, retval = NULL);
 396     require_action_quiet(theirPI, errOut, retval = NULL);
 397
 398     retval = SOSCreateActiveViewIntersectionArrayForPeerInfos(myPI, theirPI);
 399
 400 errOut:
 401     CFReleaseNull(theirPI);
 402     return retval;
 403 }
 404
 405 // This needs to create a dictionary of sets of intersected views for an account
 406 CFDictionaryRef SOSViewsCreateActiveViewMatrixDictionary(SOSAccountRef account, SOSCircleRef circle, CFErrorRef *error) {
 407     CFMutableDictionaryRef retval = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
 408     SOSPeerInfoRef myPI = SOSAccountGetMyPeerInfo(account);
 409
 410     // For now, all views require that a valid member peer is in the circle and active/valid
 411     CFMutableSetRef peers = SOSCircleCopyPeers(circle, kCFAllocatorDefault);
 412
 413     require_action_quiet(retval, errOut, SOSCreateError(kSOSErrorAllocationFailure, CFSTR("Could not allocate ViewMatrix"), NULL, error));
 414     require_action_quiet(myPI, errOut, SOSCreateError(kSOSErrorPeerNotFound, CFSTR("Could not find our PeerInfo"), NULL, error));
 415     require(peers, errOut);
 416
 417     CFSetRef myViews = SOSPeerInfoCopyEnabledViews(myPI);
 418
 419     if (myViews)
 420         CFSetForEach(myViews, ^(const void *value) {
 421             CFStringRef viewname = (CFStringRef) value;
 422             CFMutableSetRef viewset = CFSetCreateMutable(NULL, 0, &kCFTypeSetCallBacks);
 423             CFSetForEach(peers, ^(const void *peervalue) {
 424                 SOSPeerInfoRef pi = (SOSPeerInfoRef) peervalue;
 425                 CFSetRef piViews = SOSPeerInfoCopyEnabledViews(pi);
 426
 427                 if(piViews && CFSetContainsValue(piViews, viewname)) {
 428                     CFStringRef peerID = SOSPeerInfoGetPeerID(pi);
 429                     CFSetAddValue(viewset, peerID);
 430                 }
 431                 CFReleaseNull(piViews);
 432
 433             });
 434             CFDictionaryAddValue(retval, viewname, viewset);
 435         });
 436
 437     if(CFDictionaryGetCount(retval) == 0) goto errOut;  // Not really an error - just no intersection of views with anyone
 438     CFReleaseNull(peers);
 439     CFReleaseNull(myViews);
 440     return retval;
 441
 442 errOut:
 443     CFReleaseNull(retval);
 444     CFReleaseNull(peers);
 445     return NULL;
 446 }
 447
 448
 449
 450
 451
 452 /* Need XPC way to carry CFSets of views */
 453
 454
 455 CFSetRef CreateCFSetRefFromXPCObject(xpc_object_t xpcSetDER, CFErrorRef* error) {
 456     CFSetRef retval = NULL;
 457     require_action_quiet(xpcSetDER, errOut, SecCFCreateErrorWithFormat(kSecXPCErrorUnexpectedNull, sSecXPCErrorDomain, NULL, error, NULL, CFSTR("Unexpected Null Set to decode")));
 458
 459     require_action_quiet(xpc_get_type(xpcSetDER) == XPC_TYPE_DATA, errOut, SecCFCreateErrorWithFormat(kSecXPCErrorUnexpectedType, sSecXPCErrorDomain, NULL, error, NULL, CFSTR("xpcSetDER not data, got %@"), xpcSetDER));
 460
 461     const uint8_t* der = xpc_data_get_bytes_ptr(xpcSetDER);
 462     const uint8_t* der_end = der + xpc_data_get_length(xpcSetDER);
 463     der = der_decode_set(kCFAllocatorDefault, kCFPropertyListMutableContainersAndLeaves, &retval, error, der, der_end);
 464     if (der != der_end) {
 465         SecError(errSecDecode, error, CFSTR("trailing garbage at end of SecAccessControl data"));
 466         goto errOut;
 467     }
 468     return retval;
 469 errOut:
 470     CFReleaseNull(retval);
 471     return NULL;
 472 }
 473
 474 xpc_object_t CreateXPCObjectWithCFSetRef(CFSetRef setref, CFErrorRef *error) {
 475     xpc_object_t result = NULL;
 476     size_t data_size = 0;
 477     uint8_t *data = NULL;
 478     require_action_quiet(setref, errOut, SecCFCreateErrorWithFormat(kSecXPCErrorUnexpectedNull, sSecXPCErrorDomain, NULL, error, NULL, CFSTR("Unexpected Null Set to encode")));
 479     require_quiet((data_size = der_sizeof_set(setref, error)) != 0, errOut);
 480     require_quiet((data = (uint8_t *)malloc(data_size)) != NULL, errOut);
 481
 482     der_encode_set(setref, error, data, data + data_size);
 483     result = xpc_data_create(data, data_size);
 484     free(data);
 485 errOut:
 486     return result;
 487 }
 488