OSX/sec/Security/SecuritydXPC.c

   1 /*
   2  * Copyright (c) 2012-2014 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 #include <Security/SecuritydXPC.h>
  26 #include <Security/SecCFAllocator.h>
  27 #include <ipc/securityd_client.h>
  28 #include <utilities/SecCFError.h>
  29 #include <utilities/SecDb.h>
  30 #include <utilities/SecCFWrappers.h>
  31 #include <utilities/der_plist.h>
  32
  33 // TODO Shorten these string values to save ipc bandwidth.
  34 const char *kSecXPCKeyOperation = "operation";
  35 const char *kSecXPCKeyResult = "status";
  36 const char *kSecXPCKeyError = "error";
  37 const char *kSecXPCKeyClientToken = "client";
  38 const char *kSecXPCKeyPeerInfoArray = "peer-infos";
  39 const char *kSecXPCKeyPeerInfo = "peer-info";
  40 const char *kSecXPCKeyUserLabel = "userlabel";
  41 const char *kSecXPCKeyBackup = "backup";
  42 const char *kSecXPCKeyKeybag = "keybag";
  43 const char *kSecXPCKeyUserPassword = "password";
  44 const char *kSecXPCKeyDSID = "dsid";
  45 const char *kSecXPCKeyQuery = "query";
  46 const char *kSecXPCKeyAttributesToUpdate = "attributesToUpdate";
  47 const char *kSecXPCKeyDomain = "domain";
  48 const char *kSecXPCKeyDigest = "digest";
  49 const char *kSecXPCKeyCertificate = "cert";
  50 const char *kSecXPCKeySettings = "settings";
  51 const char *kSecXPCKeyOTAFileDirectory = "path";
  52 const char *kSecXPCLimitInMinutes = "limitMinutes";
  53 const char *kSecXPCPublicPeerId = "publicPeerId"; // Public peer id
  54 const char *kSecXPCOTRSession = "otrsess"; // OTR session bytes
  55 const char *kSecXPCData = "data"; // Data to process
  56 const char *kSecXPCOTRReady = "otrrdy"; // OTR ready for messages
  57 const char *kSecXPCKeyDeviceID = "deviceID";
  58 const char *kSecXPCKeySendIDSMessage = "sendIDSMessageCommand";
  59 const char *kSecXPCKeyIDSMessage = "idsMessage";
  60 const char *kSecXPCKeyViewName = "viewname";
  61 const char *kSecXPCKeyViewActionCode = "viewactioncode";
  62 const char *kSecXPCKeyHSA2AutoAcceptInfo = "autoacceptinfo";
  63 const char *kSecXPCKeyString = "cfstring";
  64 const char *kSecXPCKeyArray = "cfarray";
  65 const char *kSecXPCKeySet = "cfset";
  66 const char *kSecXPCKeySet2 = "cfset2";
  67 const char *kSecXPCKeyNewPublicBackupKey = "newPublicBackupKey";
  68 const char *kSecXPCKeyRecoveryPublicKey = "RecoveryPublicKey";
  69 const char *kSecXPCKeyIncludeV0 = "includeV0";
  70 const char *kSecXPCKeyReason = "reason";
  71 const char *kSecXPCKeyEnabledViewsKey = "enabledViews";
  72 const char *kSecXPCKeyDisabledViewsKey = "disabledViews";
  73 const char *kSecXPCKeyEscrowLabel = "escrow";
  74 const char *kSecXPCKeyTriesLabel = "tries";
  75 const char *kSecXPCKeyFileDescriptor = "fileDescriptor";
  76 const char *kSecXPCKeyAccessGroups = "accessGroups";
  77 const char *kSecXPCKeyClasses = "classes";
  78
  79
  80 //
  81 // XPC Functions for both client and server.
  82 //
  83
  84
  85 CFStringRef SOSCCGetOperationDescription(enum SecXPCOperation op)
  86 {
  87     switch (op) {
  88         case kSecXPCOpAccountSetToNew:
  89             return CFSTR("AccountSetToNew");
  90         case kSecXPCOpOTAGetEscrowCertificates:
  91             return CFSTR("OTAGetEscrowCertificates");
  92         case kSecXPCOpOTAPKIGetNewAsset:
  93             return CFSTR("OTAPKIGetNewAsset");
  94         case kSecXPCOpSetHSA2AutoAcceptInfo:
  95             return CFSTR("SetHSA2AutoAcceptInfo");
  96         case kSecXPCOpAcceptApplicants:
  97             return CFSTR("AcceptApplicants");
  98         case kSecXPCOpApplyToARing:
  99             return CFSTR("ApplyToARing");
 100         case kSecXPCOpBailFromCircle:
 101             return CFSTR("BailFromCircle");
 102         case kSecXPCOpCanAuthenticate:
 103             return CFSTR("CanAuthenticate");
 104         case kSecXPCOpCopyApplicantPeerInfo:
 105             return CFSTR("CopyApplicantPeerInfo");
 106         case kSecXPCOpCopyConcurringPeerPeerInfo:
 107             return CFSTR("CopyConcurringPeerPeerInfo");
 108         case kSecXPCOpCopyEngineState:
 109             return CFSTR("CopyEngineState");
 110         case kSecXPCOpCopyGenerationPeerInfo:
 111             return CFSTR("CopyGenerationPeerInfo");
 112         case kSecXPCOpCopyIncompatibilityInfo:
 113             return CFSTR("CopyIncompatibilityInfo");
 114         case kSecXPCOpCopyMyPeerInfo:
 115             return CFSTR("CopyMyPeerInfo");
 116         case kSecXPCOpCopyNotValidPeerPeerInfo:
 117             return CFSTR("CopyNotValidPeerPeerInfo");
 118         case kSecXPCOpCopyPeerPeerInfo:
 119             return CFSTR("CopyPeerPeerInfo");
 120         case kSecXPCOpCopyRetirementPeerInfo:
 121             return CFSTR("CopyRetirementPeerInfo");
 122         case kSecXPCOpCopyValidPeerPeerInfo:
 123             return CFSTR("CopyValidPeerPeerInfo");
 124         case kSecXPCOpCopyViewUnawarePeerInfo:
 125             return CFSTR("CopyViewUnawarePeerInfo");
 126         case kSecXPCOpDeviceInCircle:
 127             return CFSTR("DeviceInCircle");
 128         case kSecXPCOpEnableRing:
 129             return CFSTR("EnableRing");
 130         case kSecXPCOpGetAllTheRings:
 131             return CFSTR("GetAllTheRings");
 132         case kSecXPCOpGetLastDepartureReason:
 133             return CFSTR("GetLastDepartureReason");
 134         case kSecXPCOpHandleIDSMessage:
 135             return CFSTR("HandleIDSMessage");
 136         case kSecXPCOpSyncWithKVSPeer:
 137             return CFSTR("SyncKVSPeer");
 138         case kSecXPCOpSyncWithIDSPeer:
 139             return CFSTR("SyncIDSPeer");
 140         case kSecXPCOpIDSDeviceID:
 141             return CFSTR("IDSDeviceID");
 142         case kSecXPCOpClearKVSPeerMessage:
 143             return CFSTR("kSecXPCOpClearKVSPeerMessage");
 144         case kSecXPCOpLoggedOutOfAccount:
 145             return CFSTR("LoggedOutOfAccount");
 146         case kSecXPCOpPingTest:
 147             return CFSTR("PingTest");
 148         case kSecXPCOpProcessSyncWithAllPeers:
 149             return CFSTR("ProcessSyncWithAllPeers");
 150         case kSecXPCOpProcessSyncWithPeers:
 151             return CFSTR("ProcessSyncWithPeers");
 152         case kSecXPCOpProcessUnlockNotification:
 153             return CFSTR("ProcessUnlockNotification");
 154         case kSecXPCOpPurgeUserCredentials:
 155             return CFSTR("PurgeUserCredentials");
 156         case kSecXPCOpRejectApplicants:
 157             return CFSTR("RejectApplicants");
 158         case kSecXPCOpRemoveThisDeviceFromCircle:
 159             return CFSTR("RemoveThisDeviceFromCircle");
 160         case kSecXPCOpRemovePeersFromCircle:
 161             return CFSTR("RemovePeersFromCircle");
 162         case kSecXPCOpRequestDeviceID:
 163             return CFSTR("RequestDeviceID");
 164         case kSecXPCOpRequestEnsureFreshParameters:
 165             return CFSTR("RequestEnsureFreshParameters");
 166         case kSecXPCOpRequestToJoin:
 167             return CFSTR("RequestToJoin");
 168         case kSecXPCOpRequestToJoinAfterRestore:
 169             return CFSTR("RequestToJoinAfterRestore");
 170         case kSecXPCOpResetToEmpty:
 171             return CFSTR("ResetToEmpty");
 172         case kSecXPCOpResetToOffering:
 173             return CFSTR("ResetToOffering");
 174         case kSecXPCOpRingStatus:
 175             return CFSTR("RingStatus");
 176         case kSecXPCOpRollKeys:
 177             return CFSTR("RollKeys");
 178         case kSecXPCOpSecurityProperty:
 179             return CFSTR("SecurityProperty");
 180         case kSecXPCOpSendIDSMessage:
 181             return CFSTR("SendIDSMessage");
 182         case kSecXPCOpSetBagForAllSlices:
 183             return CFSTR("SetBagForAllSlices");
 184         case kSecXPCOpSetDeviceID:
 185             return CFSTR("SetDeviceID");
 186         case kSecXPCOpSetLastDepartureReason:
 187             return CFSTR("SetLastDepartureReason");
 188         case kSecXPCOpSetNewPublicBackupKey:
 189             return CFSTR("SetNewPublicBackupKey");
 190         case kSecXPCOpSetUserCredentials:
 191             return CFSTR("SetUserCredentials");
 192         case kSecXPCOpSetUserCredentialsAndDSID:
 193             return CFSTR("SetUserCredentialsAndDSID");
 194         case kSecXPCOpTryUserCredentials:
 195             return CFSTR("TryUserCredentials");
 196         case kSecXPCOpValidateUserPublic:
 197             return CFSTR("ValidateUserPublic");
 198         case kSecXPCOpView:
 199             return CFSTR("View");
 200         case kSecXPCOpWithdrawlFromARing:
 201             return CFSTR("WithdrawlFromARing");
 202         case sec_add_shared_web_credential_id:
 203             return CFSTR("add_shared_web_credential");
 204         case sec_copy_shared_web_credential_id:
 205             return CFSTR("copy_shared_web_credential");
 206         case sec_delete_all_id:
 207             return CFSTR("delete_all");
 208         case sec_get_log_settings_id:
 209             return CFSTR("get_log_settings");
 210         case sec_item_add_id:
 211             return CFSTR("add");
 212         case sec_item_backup_copy_names_id:
 213             return CFSTR("backup_copy_names");
 214         case sec_item_backup_handoff_fd_id:
 215             return CFSTR("backup_handoff_fd");
 216         case sec_item_backup_restore_id:
 217             return CFSTR("backup_restore");
 218         case sec_item_backup_set_confirmed_manifest_id:
 219             return CFSTR("backup_set_confirmed_manifest");
 220         case sec_item_copy_matching_id:
 221             return CFSTR("copy_matching");
 222         case sec_item_delete_id:
 223             return CFSTR("delete");
 224         case sec_item_update_id:
 225             return CFSTR("update");
 226         case sec_keychain_backup_id:
 227             return CFSTR("keychain_backup");
 228         case sec_keychain_backup_syncable_id:
 229             return CFSTR("keychain_backup_syncable");
 230         case sec_keychain_restore_id:
 231             return CFSTR("keychain_restore");
 232         case sec_keychain_restore_syncable_id:
 233             return CFSTR("keychain_restore_syncable");
 234         case sec_keychain_sync_update_message_id:
 235             return CFSTR("keychain_sync_update_message");
 236         case sec_ota_pki_asset_version_id:
 237             return CFSTR("ota_pki_asset_version");
 238         case sec_otr_session_create_remote_id:
 239             return CFSTR("otr_session_create_remote");
 240         case sec_otr_session_process_packet_remote_id:
 241             return CFSTR("otr_session_process_packet_remote");
 242         case sec_set_circle_log_settings_id:
 243             return CFSTR("set_circle_log_settings");
 244         case sec_set_xpc_log_settings_id:
 245             return CFSTR("set_xpc_log_settings");
 246         case sec_trust_evaluate_id:
 247             return CFSTR("trust_evaluate");
 248         case sec_trust_store_contains_id:
 249             return CFSTR("trust_store_contains");
 250         case sec_trust_store_remove_certificate_id:
 251             return CFSTR("trust_store_remove_certificate");
 252         case sec_trust_store_set_trust_settings_id:
 253             return CFSTR("trust_store_set_trust_settings");
 254         case sec_trust_store_copy_all_id:
 255             return CFSTR("trust_store_copy_all");
 256         case sec_trust_store_copy_usage_constraints_id:
 257             return CFSTR("trust_store_copy_usage_constraints");
 258         case soscc_EnsurePeerRegistration_id:
 259             return CFSTR("EnsurePeerRegistration");
 260         case kSecXPCOpSetEscrowRecord:
 261             return CFSTR("SetEscrowRecord");
 262         case kSecXPCOpGetEscrowRecord:
 263             return CFSTR("GetEscrowRecord");
 264         case kSecXPCOpWhoAmI:
 265             return CFSTR("WhoAmI");
 266         case kSecXPCOpTransmogrifyToSyncBubble:
 267             return CFSTR("TransmogrifyToSyncBubble");
 268         case kSecXPCOpWrapToBackupSliceKeyBagForView:
 269             return CFSTR("WrapToBackupSliceKeyBagForView");
 270         case kSecXPCOpCopyAccountData:
 271             return CFSTR("CopyAccountDataFromKeychain");
 272         case kSecXPCOpDeleteAccountData:
 273             return CFSTR("DeleteAccountDataFromKeychain");
 274         case kSecXPCOpCopyEngineData:
 275             return CFSTR("CopyEngineDataFromKeychain");
 276         case kSecXPCOpDeleteEngineData:
 277             return CFSTR("DeleteEngineDataFromKeychain");
 278         case sec_item_update_token_items_id:
 279             return CFSTR("UpdateTokenItems");
 280         case sec_delete_items_with_access_groups_id:
 281             return CFSTR("sec_delete_items_with_access_groups_id");
 282         case kSecXPCOpPeersHaveViewsEnabled:
 283             return CFSTR("kSecXPCOpPeersHaveViewsEnabled");
 284         case kSecXPCOpRegisterRecoveryPublicKey:
 285             return CFSTR("RegisterRecoveryPublicKey");
 286         case kSecXPCOpGetRecoveryPublicKey:
 287             return CFSTR("GetRecoveryPublicKey");
 288         case kSecXPCOpCopyBackupInformation:
 289             return CFSTR("CopyBackupInformation");
 290         case sec_device_is_internal_id:
 291             return CFSTR("DeviceIsInternal");
 292         case kSecXPCOpMessageFromPeerIsPending:
 293             return CFSTR("MessageFromPeerIsPending");
 294         case kSecXPCOpSendToPeerIsPending:
 295             return CFSTR("SendToPeerIsPending");
 296         default:
 297             return CFSTR("Unknown xpc operation");
 298     }
 299 }
 300
 301 bool SecXPCDictionarySetPList(xpc_object_t message, const char *key, CFTypeRef object, CFErrorRef *error)
 302 {
 303     if (!object)
 304         return SecError(errSecParam, error, CFSTR("object for key %s is NULL"), key);
 305
 306     size_t size = der_sizeof_plist(object, error);
 307     if (!size)
 308         return false;
 309     uint8_t *der = malloc(size);
 310     uint8_t *der_end = der + size;
 311     uint8_t *der_start = der_encode_plist(object, error, der, der_end);
 312     if (!der_start) {
 313         free(der);
 314         return false;
 315     }
 316
 317     assert(der == der_start);
 318     xpc_dictionary_set_data(message, key, der_start, der_end - der_start);
 319     free(der);
 320     return true;
 321 }
 322
 323 bool SecXPCDictionarySetPListOptional(xpc_object_t message, const char *key, CFTypeRef object, CFErrorRef *error) {
 324     return !object || SecXPCDictionarySetPList(message, key, object, error);
 325 }
 326
 327 bool SecXPCDictionarySetData(xpc_object_t message, const char *key, CFDataRef data, CFErrorRef *error)
 328 {
 329     if (!data)
 330         return SecError(errSecParam, error, CFSTR("data for key %s is NULL"), key);
 331
 332     xpc_dictionary_set_data(message, key, CFDataGetBytePtr(data), CFDataGetLength(data));
 333     return true;
 334 }
 335
 336 bool SecXPCDictionarySetBool(xpc_object_t message, const char *key, bool value, CFErrorRef *error)
 337 {
 338     xpc_dictionary_set_bool(message, key, value);
 339     return true;
 340 }
 341
 342 bool SecXPCDictionarySetString(xpc_object_t message, const char *key, CFStringRef string, CFErrorRef *error)
 343 {
 344     if (!string)
 345         return SecError(errSecParam, error, CFSTR("string for key %s is NULL"), key);
 346
 347     __block bool ok = true;
 348     CFStringPerformWithCString(string, ^(const char *utf8Str) {
 349         if (utf8Str)
 350             xpc_dictionary_set_string(message, key, utf8Str);
 351         else
 352             ok = SecError(errSecParam, error, CFSTR("failed to convert string for key %s to utf8"), key);
 353     });
 354     return ok;
 355 }
 356
 357 bool SecXPCDictionarySetStringOptional(xpc_object_t message, const char *key, CFStringRef string, CFErrorRef *error) {
 358     return !string || SecXPCDictionarySetString(message, key, string, error);
 359 }
 360
 361 bool SecXPCDictionarySetDataOptional(xpc_object_t message, const char *key, CFDataRef data, CFErrorRef *error) {
 362     return !data || SecXPCDictionarySetData(message, key, data, error);
 363 }
 364
 365 bool SecXPCDictionarySetInt64(xpc_object_t message, const char *key, int64_t value, CFErrorRef *error) {
 366     xpc_dictionary_set_int64(message, key, value);
 367     return true;
 368 }
 369
 370 bool SecXPCDictionarySetFileDescriptor(xpc_object_t message, const char *key, int fd, CFErrorRef *error) {
 371     xpc_dictionary_set_fd(message, key, fd);
 372     return true;
 373 }
 374
 375 int SecXPCDictionaryDupFileDescriptor(xpc_object_t message, const char *key, CFErrorRef *error) {
 376     int fd = xpc_dictionary_dup_fd(message, key);
 377     if (fd < 0)
 378         SecError(errSecParam, error, CFSTR("missing fd for key %s"), key);
 379
 380     return fd;
 381 }
 382
 383 CFSetRef SecXPCDictionaryCopySet(xpc_object_t message, const char *key, CFErrorRef *error) {
 384     CFTypeRef obj = SecXPCDictionaryCopyPList(message, key, error);
 385     CFSetRef set = copyIfSet(obj, error);
 386     if (obj && !set) {
 387         CFStringRef description = CFCopyTypeIDDescription(CFGetTypeID(obj));
 388         SecError(errSecParam, error, CFSTR("object for key %s not set but %@"), key, description);
 389         CFReleaseNull(description);
 390     }
 391     CFReleaseNull(obj);
 392     return set;
 393 }
 394
 395 CFArrayRef SecXPCDictionaryCopyArray(xpc_object_t message, const char *key, CFErrorRef *error) {
 396     CFTypeRef array = SecXPCDictionaryCopyPList(message, key, error);
 397     if (array) {
 398         CFTypeID type_id = CFGetTypeID(array);
 399         if (type_id != CFArrayGetTypeID()) {
 400             CFStringRef description = CFCopyTypeIDDescription(type_id);
 401             SecError(errSecParam, error, CFSTR("object for key %s not array but %@"), key, description);
 402             CFReleaseNull(description);
 403             CFReleaseNull(array);
 404         }
 405     }
 406     return (CFArrayRef)array;
 407 }
 408
 409 bool SecXPCDictionaryCopyArrayOptional(xpc_object_t message, const char *key, CFArrayRef *parray, CFErrorRef *error) {
 410     if (!xpc_dictionary_get_value(message, key)) {
 411         *parray = NULL;
 412         return true;
 413     }
 414     *parray = SecXPCDictionaryCopyArray(message, key, error);
 415     return *parray;
 416 }
 417
 418 CFDataRef SecXPCDictionaryCopyData(xpc_object_t message, const char *key, CFErrorRef *error) {
 419     CFDataRef data = NULL;
 420     size_t size = 0;
 421     const uint8_t *bytes = xpc_dictionary_get_data(message, key, &size);
 422     if (!bytes) {
 423         SecError(errSecParam, error, CFSTR("no data for key %s"), key);
 424         return NULL;
 425     }
 426
 427     data = CFDataCreate(kCFAllocatorDefault, bytes, size);
 428     if (!data)
 429         SecError(errSecParam, error, CFSTR("failed to create data for key %s"), key);
 430
 431     return data;
 432 }
 433
 434 bool SecXPCDictionaryGetBool(xpc_object_t message, const char *key, CFErrorRef *__unused error) {
 435     return xpc_dictionary_get_bool(message, key);
 436 }
 437
 438 bool SecXPCDictionaryCopyDataOptional(xpc_object_t message, const char *key, CFDataRef *pdata, CFErrorRef *error) {
 439     size_t size = 0;
 440     if (!xpc_dictionary_get_data(message, key, &size)) {
 441         *pdata = NULL;
 442         return true;
 443     }
 444     *pdata = SecXPCDictionaryCopyData(message, key, error);
 445     return *pdata;
 446 }
 447
 448 CFDictionaryRef SecXPCDictionaryCopyDictionary(xpc_object_t message, const char *key, CFErrorRef *error) {
 449     CFTypeRef dict = SecXPCDictionaryCopyPList(message, key, error);
 450     if (dict) {
 451         CFTypeID type_id = CFGetTypeID(dict);
 452         if (type_id != CFDictionaryGetTypeID()) {
 453             CFStringRef description = CFCopyTypeIDDescription(type_id);
 454             SecError(errSecParam, error, CFSTR("object for key %s not dictionary but %@"), key, description);
 455             CFReleaseNull(description);
 456             CFReleaseNull(dict);
 457         }
 458     }
 459     return (CFDictionaryRef)dict;
 460 }
 461
 462 bool SecXPCDictionaryCopyDictionaryOptional(xpc_object_t message, const char *key, CFDictionaryRef *pdictionary, CFErrorRef *error) {
 463     if (!xpc_dictionary_get_value(message, key)) {
 464         *pdictionary = NULL;
 465         return true;
 466     }
 467     *pdictionary = SecXPCDictionaryCopyDictionary(message, key, error);
 468     return *pdictionary;
 469 }
 470
 471 CFTypeRef SecXPCDictionaryCopyPList(xpc_object_t message, const char *key, CFErrorRef *error)
 472 {
 473     CFTypeRef cfobject = NULL;
 474     size_t size = 0;
 475     const uint8_t *der = xpc_dictionary_get_data(message, key, &size);
 476     if (!der) {
 477         SecError(errSecParam, error, CFSTR("no object for key %s"), key);
 478         return NULL;
 479     }
 480
 481     const uint8_t *der_end = der + size;
 482     /* use the sensitive allocator so that the dictionary is zeroized upon deallocation */
 483     const uint8_t *decode_end = der_decode_plist(SecCFAllocatorZeroize(), kCFPropertyListImmutable,
 484                                           &cfobject, error, der, der_end);
 485     if (decode_end != der_end) {
 486         SecError(errSecParam, error, CFSTR("trailing garbage after der decoded object for key %s"), key);
 487         CFReleaseNull(cfobject);
 488     }
 489
 490     /* zeroize xpc value as it may have contained raw key material */
 491     cc_clear(size, (void *)der);
 492
 493     return cfobject;
 494 }
 495
 496 bool SecXPCDictionaryCopyPListOptional(xpc_object_t message, const char *key, CFTypeRef *pobject, CFErrorRef *error) {
 497     size_t size = 0;
 498     if (!xpc_dictionary_get_data(message, key, &size)) {
 499         *pobject = NULL;
 500         return true;
 501     }
 502     *pobject = SecXPCDictionaryCopyPList(message, key, error);
 503     return *pobject;
 504 }
 505
 506 CFStringRef SecXPCDictionaryCopyString(xpc_object_t message, const char *key, CFErrorRef *error) {
 507     const char *string = xpc_dictionary_get_string(message, key);
 508     if (string) {
 509         CFStringRef result = CFStringCreateWithCString(kCFAllocatorDefault, string, kCFStringEncodingUTF8);
 510         if (!result) {
 511             SecError(errSecAllocate, error, CFSTR("object for key %s failed to convert %s to CFString"), key, string);
 512         }
 513         return result;
 514     } else {
 515         SecError(errSecParam, error, CFSTR("object for key %s not string"), key);
 516         return NULL;
 517     }
 518 }
 519
 520 bool SecXPCDictionaryCopyStringOptional(xpc_object_t message, const char *key, CFStringRef *pstring, CFErrorRef *error) {
 521     if (!xpc_dictionary_get_value(message, key)) {
 522         *pstring = NULL;
 523         return true;
 524     }
 525     *pstring = SecXPCDictionaryCopyString(message, key, error);
 526     return *pstring;
 527 }