keychain/ot/OTRamping.m

   1 /*
   2  * Copyright (c) 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 #if OCTAGON
  25
  26 #import <Foundation/Foundation.h>
  27 #import <CoreFoundation/CoreFoundation.h>
  28 #import <CloudKit/CloudKit.h>
  29 #import <CloudKit/CKContainer_Private.h>
  30 #import <utilities/debugging.h>
  31 #import "OTRamping.h"
  32 #import "keychain/ckks/CKKS.h"
  33 #import "keychain/ckks/CKKSNearFutureScheduler.h"
  34 #import "keychain/ckks/CKKSAnalytics.h"
  35 #import "keychain/ot/OTDefines.h"
  36 #import "keychain/ot/OTConstants.h"
  37 #import "keychain/ckks/CKKS.h"
  38
  39 static NSString* kFeatureAllowedKey =       @"FeatureAllowed";
  40 static NSString* kFeaturePromotedKey =      @"FeaturePromoted";
  41 static NSString* kFeatureVisibleKey =       @"FeatureVisible";
  42 static NSString* kRetryAfterKey =           @"RetryAfter";
  43 static NSString* kRampPriorityKey =         @"RampPriority";
  44
  45 #define kCKRampManagerDefaultRetryTimeInSeconds 86400
  46
  47 #if OCTAGON
  48 @interface OTRamp (lockstateTracker) <CKKSLockStateNotification>
  49 @end
  50 #endif
  51
  52 @interface OTRamp ()
  53 @property (nonatomic, strong) CKContainer   *container;
  54 @property (nonatomic, strong) CKDatabase    *database;
  55
  56 @property (nonatomic, strong) CKRecordZone      *zone;
  57 @property (nonatomic, strong) CKRecordZoneID    *zoneID;
  58
  59 @property (nonatomic, strong) NSString      *recordName;
  60 @property (nonatomic, strong) NSString      *localSettingName;
  61 @property (nonatomic, strong) CKRecordID    *recordID;
  62
  63 @property (nonatomic, strong) CKKSAccountStateTracker *accountTracker;
  64 @property (nonatomic, strong) CKKSLockStateTracker      *lockStateTracker;
  65 @property (nonatomic, strong) CKKSReachabilityTracker   *reachabilityTracker;
  66
  67 @property CKKSAccountStatus accountStatus;
  68
  69 @property (readonly) Class<CKKSFetchRecordsOperation> fetchRecordRecordsOperationClass;
  70
  71 @property (atomic, strong) NSDate *lastFetch;
  72 @property (atomic) NSTimeInterval retryAfter;
  73 @property (atomic) BOOL cachedFeatureAllowed;
  74
  75 @end
  76
  77 @implementation OTRamp
  78
  79 -(instancetype) initWithRecordName:(NSString *) recordName
  80                   localSettingName:(NSString*) localSettingName
  81                          container:(CKContainer*) container
  82                           database:(CKDatabase*) database
  83                             zoneID:(CKRecordZoneID*) zoneID
  84                     accountTracker:(CKKSAccountStateTracker*) accountTracker
  85                   lockStateTracker:(CKKSLockStateTracker*) lockStateTracker
  86                reachabilityTracker:(CKKSReachabilityTracker*) reachabilityTracker
  87 fetchRecordRecordsOperationClass:(Class<CKKSFetchRecordsOperation>) fetchRecordRecordsOperationClass
  88
  89 {
  90     if ((self = [super init])) {
  91         _container = container;
  92         _recordName = [recordName copy];
  93         _localSettingName = [localSettingName copy];
  94         _database = database;
  95         _zoneID = zoneID;
  96         _accountTracker = accountTracker;
  97         _lockStateTracker = lockStateTracker;
  98         _reachabilityTracker = reachabilityTracker;
  99         _fetchRecordRecordsOperationClass = fetchRecordRecordsOperationClass;
 100         _lastFetch = [NSDate distantPast];
 101         _retryAfter = kCKRampManagerDefaultRetryTimeInSeconds;
 102         _cachedFeatureAllowed = NO;
 103     }
 104     return self;
 105 }
 106
 107 -(void)fetchRampRecord:(CKOperationDiscretionaryNetworkBehavior)networkBehavior reply:(void (^)(BOOL featureAllowed, BOOL featurePromoted, BOOL featureVisible, NSInteger retryAfter, NSError *rampStateFetchError))recordRampStateFetchCompletionBlock
 108 {
 109     __weak __typeof(self) weakSelf = self;
 110
 111     CKOperationConfiguration *opConfig = [[CKOperationConfiguration alloc] init];
 112     opConfig.allowsCellularAccess = YES;
 113     opConfig.discretionaryNetworkBehavior = networkBehavior;
 114     opConfig.isCloudKitSupportOperation = YES;
 115
 116     _recordID = [[CKRecordID alloc] initWithRecordName:_recordName zoneID:_zoneID];
 117     CKFetchRecordsOperation *operation = [[[self.fetchRecordRecordsOperationClass class] alloc] initWithRecordIDs:@[ _recordID]];
 118
 119     operation.desiredKeys = @[kFeatureAllowedKey, kFeaturePromotedKey, kFeatureVisibleKey, kRetryAfterKey];
 120
 121     operation.configuration = opConfig;
 122     operation.fetchRecordsCompletionBlock = ^(NSDictionary<CKRecordID *,CKRecord *> * _Nullable recordsByRecordID, NSError * _Nullable operationError) {
 123         __strong __typeof(weakSelf) strongSelf = weakSelf;
 124         if(!strongSelf) {
 125             secnotice("octagon", "received callback for released object");
 126             operationError = [NSError errorWithDomain:OctagonErrorDomain code:OTErrorCKCallback userInfo:@{NSLocalizedDescriptionKey: @"Received callback for released object"}];
 127             recordRampStateFetchCompletionBlock(NO, NO, NO, kCKRampManagerDefaultRetryTimeInSeconds , operationError);
 128             return;
 129         }
 130
 131         BOOL featureAllowed = NO;
 132         BOOL featurePromoted = NO;
 133         BOOL featureVisible = NO;
 134         NSInteger retryAfter = kCKRampManagerDefaultRetryTimeInSeconds;
 135
 136         secnotice("octagon", "Fetch operation records %@ fetchError %@", recordsByRecordID, operationError);
 137         // There should only be only one record.
 138         CKRecord *rampRecord = recordsByRecordID[strongSelf.recordID];
 139
 140         if (rampRecord) {
 141             featureAllowed = [rampRecord[kFeatureAllowedKey] boolValue];
 142             featurePromoted = [rampRecord[kFeaturePromotedKey] boolValue];
 143             featureVisible = [rampRecord[kFeatureVisibleKey] boolValue];
 144             retryAfter = [rampRecord[kRetryAfterKey] integerValue];
 145
 146             secnotice("octagon", "Fetch ramp state - featureAllowed %@, featurePromoted: %@, featureVisible: %@, retryAfter: %ld", (featureAllowed ? @YES : @NO), (featurePromoted ? @YES : @NO), (featureVisible ? @YES : @NO), (long)retryAfter);
 147         } else {
 148             secerror("octagon: Couldn't find CKRecord for ramp. Defaulting to not ramped in");
 149             operationError = [NSError errorWithDomain:OctagonErrorDomain code:OTErrorRecordNotFound userInfo:@{NSLocalizedDescriptionKey: @" Couldn't find CKRecord for ramp. Defaulting to not ramped in"}];
 150         }
 151         recordRampStateFetchCompletionBlock(featureAllowed, featurePromoted, featureVisible, retryAfter, operationError);
 152     };
 153
 154     [self.database addOperation: operation];
 155     secnotice("octagon", "Attempting to fetch ramp state from CloudKit");
 156 }
 157
 158 -(BOOL) checkRampStateWithError:(NSError**)error
 159 {
 160     __block BOOL isFeatureEnabled = NO;
 161     __block NSError* localError = nil;
 162     __block NSInteger localRetryAfter = 0;
 163
 164     //defaults write to for whether or not a ramp record returns "enabled or disabled"
 165     CFBooleanRef enabled = (CFBooleanRef)CFPreferencesCopyValue((__bridge CFStringRef)self.localSettingName,
 166                                                                 CFSTR("com.apple.security"),
 167                                                                 kCFPreferencesCurrentUser, kCFPreferencesAnyHost);
 168
 169     secnotice("octagon", "%@ Defaults availability: SecCKKSTestsEnabled[%s] DefaultsPointer[%s] DefaultsValue[%s]", (__bridge CFStringRef)self.localSettingName,
 170               SecCKKSTestsEnabled() ? "True": "False", (enabled != NULL) ? "True": "False",
 171               (enabled && (CFGetTypeID(enabled) == CFBooleanGetTypeID()) && (enabled == kCFBooleanTrue)) ? "True": "False");
 172
 173     if(!SecCKKSTestsEnabled() && enabled && CFGetTypeID(enabled) == CFBooleanGetTypeID()){
 174         BOOL localConfigEnable = (enabled == kCFBooleanTrue);
 175         secnotice("octagon", "feature is %@: %@ (local config)", localConfigEnable ? @"enabled" : @"disabled", self.recordName);
 176         CFReleaseNull(enabled);
 177         return localConfigEnable;
 178     }
 179     CFReleaseNull(enabled);
 180
 181     NSDate* now = [[NSDate alloc] init];
 182
 183     if([now timeIntervalSinceDate: self.lastFetch] < self.retryAfter) {
 184         return self.cachedFeatureAllowed;
 185     }
 186
 187     if(self.lockStateTracker.isLocked){
 188         secnotice("octagon","device is locked! can't check ramp state");
 189         localError = [NSError errorWithDomain:(__bridge NSString*)kSecErrorDomain
 190                                          code:errSecInteractionNotAllowed
 191                                      userInfo:@{NSLocalizedDescriptionKey: @"device is locked"}];
 192         if(error){
 193             *error = localError;
 194         }
 195         return NO;
 196     }
 197
 198     // Wait until the account tracker has had a chance to figure out the state
 199     [self.accountTracker.ckAccountInfoInitialized wait:5*NSEC_PER_SEC];
 200     if(self.accountTracker.currentCKAccountInfo.accountStatus != CKAccountStatusAvailable){
 201         secnotice("octagon","not signed in! can't check ramp state");
 202         localError = [NSError errorWithDomain:OctagonErrorDomain
 203                                          code:OTErrorNotSignedIn
 204                                      userInfo:@{NSLocalizedDescriptionKey: @"not signed in"}];
 205         if(error){
 206             *error = localError;
 207         }
 208         return NO;
 209     }
 210     if(!self.reachabilityTracker.currentReachability){
 211         secnotice("octagon","no network! can't check ramp state");
 212         localError = [NSError errorWithDomain:OctagonErrorDomain
 213                                          code:OTErrorNoNetwork
 214                                      userInfo:@{NSLocalizedDescriptionKey: @"no network"}];
 215         if(error){
 216             *error = localError;
 217         }
 218         return NO;
 219     }
 220
 221     CKKSAnalytics* logger = [CKKSAnalytics logger];
 222     SFAnalyticsActivityTracker *tracker = [logger logSystemMetricsForActivityNamed:CKKSActivityOTFetchRampState withAction:nil];
 223
 224     dispatch_semaphore_t sema = dispatch_semaphore_create(0);
 225
 226     [tracker start];
 227
 228     [self fetchRampRecord:CKOperationDiscretionaryNetworkBehaviorNonDiscretionary reply:^(BOOL featureAllowed, BOOL featurePromoted, BOOL featureVisible, NSInteger retryAfter, NSError *rampStateFetchError) {
 229         secnotice("octagon", "fetch ramp records returned with featureAllowed: %d,\n featurePromoted: %d,\n featureVisible: %d,\n", featureAllowed, featurePromoted, featureVisible);
 230
 231         isFeatureEnabled = featureAllowed;
 232         localRetryAfter = retryAfter;
 233         if(rampStateFetchError){
 234             localError = rampStateFetchError;
 235         }
 236         dispatch_semaphore_signal(sema);
 237     }];
 238
 239     int64_t timeout = (int64_t)(SecCKKSTestsEnabled() ? 2*NSEC_PER_SEC : NSEC_PER_SEC * 65);
 240     if(dispatch_semaphore_wait(sema, dispatch_time(DISPATCH_TIME_NOW, timeout)) != 0) {
 241         secnotice("octagon", "timed out waiting for response from CloudKit\n");
 242         localError = [NSError errorWithDomain:OctagonErrorDomain code:OTErrorCKTimeOut userInfo:@{NSLocalizedDescriptionKey: @"timed out waiting for response from CloudKit"}];
 243
 244         [logger logUnrecoverableError:localError forEvent:OctagonEventRamp withAttributes:@{
 245                                                                                             OctagonEventAttributeFailureReason : @"cloud kit timed out"}
 246          ];
 247     }
 248
 249     [tracker stop];
 250
 251     if(localRetryAfter > 0){
 252         secnotice("octagon", "cloud kit asked security to retry: %lu", (unsigned long)localRetryAfter);
 253         self.retryAfter = localRetryAfter;
 254     }
 255
 256     if(localError){
 257         secerror("octagon: had an error fetching ramp state: %@", localError);
 258         [logger logUnrecoverableError:localError forEvent:OctagonEventRamp withAttributes:@{
 259                                                                                             OctagonEventAttributeFailureReason : @"fetching ramp state"}
 260          ];
 261         if(error){
 262             *error = localError;
 263         }
 264     }
 265     if(isFeatureEnabled){
 266         [logger logSuccessForEventNamed:OctagonEventRamp];
 267     }
 268
 269     self.lastFetch = now;
 270     self.cachedFeatureAllowed = isFeatureEnabled;
 271     return isFeatureEnabled;
 272 }
 273
 274 @end
 275 #endif
 276
 277