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     self = [super init];
  91     if(self){
  92         _container = container;
  93         _recordName = [recordName copy];
  94         _localSettingName = [localSettingName copy];
  95         _database = database;
  96         _zoneID = zoneID;
  97         _accountTracker = accountTracker;
  98         _lockStateTracker = lockStateTracker;
  99         _reachabilityTracker = reachabilityTracker;
 100         _fetchRecordRecordsOperationClass = fetchRecordRecordsOperationClass;
 101         _lastFetch = [NSDate distantPast];
 102         _retryAfter = kCKRampManagerDefaultRetryTimeInSeconds;
 103         _cachedFeatureAllowed = NO;
 104     }
 105     return self;
 106 }
 107
 108 -(void)fetchRampRecord:(CKOperationDiscretionaryNetworkBehavior)networkBehavior reply:(void (^)(BOOL featureAllowed, BOOL featurePromoted, BOOL featureVisible, NSInteger retryAfter, NSError *rampStateFetchError))recordRampStateFetchCompletionBlock
 109 {
 110     __weak __typeof(self) weakSelf = self;
 111
 112     CKOperationConfiguration *opConfig = [[CKOperationConfiguration alloc] init];
 113     opConfig.allowsCellularAccess = YES;
 114     opConfig.discretionaryNetworkBehavior = networkBehavior;
 115     opConfig.isCloudKitSupportOperation = YES;
 116
 117     _recordID = [[CKRecordID alloc] initWithRecordName:_recordName zoneID:_zoneID];
 118     CKFetchRecordsOperation *operation = [[[self.fetchRecordRecordsOperationClass class] alloc] initWithRecordIDs:@[ _recordID]];
 119
 120     operation.desiredKeys = @[kFeatureAllowedKey, kFeaturePromotedKey, kFeatureVisibleKey, kRetryAfterKey];
 121
 122     operation.configuration = opConfig;
 123     operation.fetchRecordsCompletionBlock = ^(NSDictionary<CKRecordID *,CKRecord *> * _Nullable recordsByRecordID, NSError * _Nullable operationError) {
 124         __strong __typeof(weakSelf) strongSelf = weakSelf;
 125         if(!strongSelf) {
 126             secnotice("octagon", "received callback for released object");
 127             operationError = [NSError errorWithDomain:OctagonErrorDomain code:OTErrorCKCallback userInfo:@{NSLocalizedDescriptionKey: @"Received callback for released object"}];
 128             recordRampStateFetchCompletionBlock(NO, NO, NO, kCKRampManagerDefaultRetryTimeInSeconds , operationError);
 129             return;
 130         }
 131
 132         BOOL featureAllowed = NO;
 133         BOOL featurePromoted = NO;
 134         BOOL featureVisible = NO;
 135         NSInteger retryAfter = kCKRampManagerDefaultRetryTimeInSeconds;
 136
 137         secnotice("octagon", "Fetch operation records %@ fetchError %@", recordsByRecordID, operationError);
 138         // There should only be only one record.
 139         CKRecord *rampRecord = recordsByRecordID[strongSelf.recordID];
 140
 141         if (rampRecord) {
 142             featureAllowed = [rampRecord[kFeatureAllowedKey] boolValue];
 143             featurePromoted = [rampRecord[kFeaturePromotedKey] boolValue];
 144             featureVisible = [rampRecord[kFeatureVisibleKey] boolValue];
 145             retryAfter = [rampRecord[kRetryAfterKey] integerValue];
 146
 147             secnotice("octagon", "Fetch ramp state - featureAllowed %@, featurePromoted: %@, featureVisible: %@, retryAfter: %ld", (featureAllowed ? @YES : @NO), (featurePromoted ? @YES : @NO), (featureVisible ? @YES : @NO), (long)retryAfter);
 148         } else {
 149             secerror("octagon: Couldn't find CKRecord for ramp. Defaulting to not ramped in");
 150             operationError = [NSError errorWithDomain:OctagonErrorDomain code:OTErrorRecordNotFound userInfo:@{NSLocalizedDescriptionKey: @" Couldn't find CKRecord for ramp. Defaulting to not ramped in"}];
 151         }
 152         recordRampStateFetchCompletionBlock(featureAllowed, featurePromoted, featureVisible, retryAfter, operationError);
 153     };
 154
 155     [self.database addOperation: operation];
 156     secnotice("octagon", "Attempting to fetch ramp state from CloudKit");
 157 }
 158
 159 -(BOOL) checkRampStateWithError:(NSError**)error
 160 {
 161     __block BOOL isFeatureEnabled = NO;
 162     __block NSError* localError = nil;
 163     __block NSInteger localRetryAfter = 0;
 164
 165     //defaults write to for whether or not a ramp record returns "enabled or disabled"
 166     CFBooleanRef enabled = (CFBooleanRef)CFPreferencesCopyValue((__bridge CFStringRef)self.localSettingName,
 167                                                                 CFSTR("com.apple.security"),
 168                                                                 kCFPreferencesCurrentUser, kCFPreferencesAnyHost);
 169
 170     secnotice("octagon", "%@ Defaults availability: SecCKKSTestsEnabled[%s] DefaultsPointer[%s] DefaultsValue[%s]", (__bridge CFStringRef)self.localSettingName,
 171               SecCKKSTestsEnabled() ? "True": "False", (enabled != NULL) ? "True": "False",
 172               (enabled && (CFGetTypeID(enabled) == CFBooleanGetTypeID()) && (enabled == kCFBooleanTrue)) ? "True": "False");
 173
 174     if(!SecCKKSTestsEnabled() && enabled && CFGetTypeID(enabled) == CFBooleanGetTypeID()){
 175         BOOL localConfigEnable = (enabled == kCFBooleanTrue);
 176         secnotice("octagon", "feature is %@: %@ (local config)", localConfigEnable ? @"enabled" : @"disabled", self.recordName);
 177         CFReleaseNull(enabled);
 178         return localConfigEnable;
 179     }
 180     CFReleaseNull(enabled);
 181
 182     NSDate* now = [[NSDate alloc] init];
 183
 184     if([now timeIntervalSinceDate: self.lastFetch] < self.retryAfter) {
 185         return self.cachedFeatureAllowed;
 186     }
 187
 188     if(self.lockStateTracker.isLocked){
 189         secnotice("octagon","device is locked! can't check ramp state");
 190         localError = [NSError errorWithDomain:(__bridge NSString*)kSecErrorDomain
 191                                          code:errSecInteractionNotAllowed
 192                                      userInfo:@{NSLocalizedDescriptionKey: @"device is locked"}];
 193         if(error){
 194             *error = localError;
 195         }
 196         return NO;
 197     }
 198
 199     // Wait until the account tracker has had a chance to figure out the state
 200     [self.accountTracker.ckAccountInfoInitialized wait:5*NSEC_PER_SEC];
 201     if(self.accountTracker.currentCKAccountInfo.accountStatus != CKAccountStatusAvailable){
 202         secnotice("octagon","not signed in! can't check ramp state");
 203         localError = [NSError errorWithDomain:OctagonErrorDomain
 204                                          code:OTErrorNotSignedIn
 205                                      userInfo:@{NSLocalizedDescriptionKey: @"not signed in"}];
 206         if(error){
 207             *error = localError;
 208         }
 209         return NO;
 210     }
 211     if(!self.reachabilityTracker.currentReachability){
 212         secnotice("octagon","no network! can't check ramp state");
 213         localError = [NSError errorWithDomain:OctagonErrorDomain
 214                                          code:OTErrorNoNetwork
 215                                      userInfo:@{NSLocalizedDescriptionKey: @"no network"}];
 216         if(error){
 217             *error = localError;
 218         }
 219         return NO;
 220     }
 221
 222     CKKSAnalytics* logger = [CKKSAnalytics logger];
 223     SFAnalyticsActivityTracker *tracker = [logger logSystemMetricsForActivityNamed:CKKSActivityOTFetchRampState withAction:nil];
 224
 225     dispatch_semaphore_t sema = dispatch_semaphore_create(0);
 226
 227     [tracker start];
 228
 229     [self fetchRampRecord:CKOperationDiscretionaryNetworkBehaviorNonDiscretionary reply:^(BOOL featureAllowed, BOOL featurePromoted, BOOL featureVisible, NSInteger retryAfter, NSError *rampStateFetchError) {
 230         secnotice("octagon", "fetch ramp records returned with featureAllowed: %d,\n featurePromoted: %d,\n featureVisible: %d,\n", featureAllowed, featurePromoted, featureVisible);
 231
 232         isFeatureEnabled = featureAllowed;
 233         localRetryAfter = retryAfter;
 234         if(rampStateFetchError){
 235             localError = rampStateFetchError;
 236         }
 237         dispatch_semaphore_signal(sema);
 238     }];
 239
 240     int64_t timeout = (int64_t)(SecCKKSTestsEnabled() ? 2*NSEC_PER_SEC : NSEC_PER_SEC * 65);
 241     if(dispatch_semaphore_wait(sema, dispatch_time(DISPATCH_TIME_NOW, timeout)) != 0) {
 242         secnotice("octagon", "timed out waiting for response from CloudKit\n");
 243         localError = [NSError errorWithDomain:OctagonErrorDomain code:OTErrorCKTimeOut userInfo:@{NSLocalizedDescriptionKey: @"timed out waiting for response from CloudKit"}];
 244
 245         [logger logUnrecoverableError:localError forEvent:OctagonEventRamp withAttributes:@{
 246                                                                                             OctagonEventAttributeFailureReason : @"cloud kit timed out"}
 247          ];
 248     }
 249
 250     [tracker stop];
 251
 252     if(localRetryAfter > 0){
 253         secnotice("octagon", "cloud kit asked security to retry: %lu", (unsigned long)localRetryAfter);
 254         self.retryAfter = localRetryAfter;
 255     }
 256
 257     if(localError){
 258         secerror("octagon: had an error fetching ramp state: %@", localError);
 259         [logger logUnrecoverableError:localError forEvent:OctagonEventRamp withAttributes:@{
 260                                                                                             OctagonEventAttributeFailureReason : @"fetching ramp state"}
 261          ];
 262         if(error){
 263             *error = localError;
 264         }
 265     }
 266     if(isFeatureEnabled){
 267         [logger logSuccessForEventNamed:OctagonEventRamp];
 268     }
 269
 270     self.lastFetch = now;
 271     self.cachedFeatureAllowed = isFeatureEnabled;
 272     return isFeatureEnabled;
 273 }
 274
 275 @end
 276 #endif
 277
 278