CKKSCKAccountStateTracker.m [plain text]
/*
* Copyright (c) 2017 Apple Inc. All Rights Reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this
* file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
#if OCTAGON
#include <dispatch/dispatch.h>
#include <utilities/debugging.h>
#include <Security/SecureObjectSync/SOSCloudCircle.h>
#include <Security/SecureObjectSync/SOSCloudCircleInternal.h>
#include <Security/SecureObjectSync/SOSInternal.h>
#include <notify.h>
#import "keychain/ckks/CKKS.h"
#import "keychain/ckks/CloudKitCategories.h"
#import "keychain/ckks/CKKSCKAccountStateTracker.h"
#import "keychain/ckks/CKKSAnalytics.h"
@interface CKKSCKAccountStateTracker ()
@property (readonly) Class<CKKSNSNotificationCenter> nsnotificationCenterClass;
@property CKKSAccountStatus currentComputedAccountStatus;
@property (nullable, atomic) NSError* currentAccountError;
@property dispatch_queue_t queue;
@property NSMapTable<dispatch_queue_t, id<CKKSAccountStateListener>>* changeListeners;
@property CKContainer* container; // used only for fetching the CKAccountStatus
/* We have initialization races. We should report CKKSAccountStatusUnknown until both of
* these are true, otherwise on a race, it looks like we logged out. */
@property bool firstCKAccountFetch;
@property bool firstSOSCircleFetch;
@end
@implementation CKKSCKAccountStateTracker
-(instancetype)init: (CKContainer*) container nsnotificationCenterClass: (Class<CKKSNSNotificationCenter>) nsnotificationCenterClass {
if((self = [super init])) {
_nsnotificationCenterClass = nsnotificationCenterClass;
_changeListeners = [NSMapTable strongToWeakObjectsMapTable]; // Backwards from how we'd like, but it's the best way to have weak pointers to CKKSAccountStateListener.
_currentCKAccountInfo = nil;
_currentCircleStatus = kSOSCCError;
_currentComputedAccountStatus = CKKSAccountStatusUnknown;
_currentComputedAccountStatusValid = [[CKKSCondition alloc] init];
_container = container;
_queue = dispatch_queue_create("ck-account-state", DISPATCH_QUEUE_SERIAL_WITH_AUTORELEASE_POOL);
_firstCKAccountFetch = false;
_firstSOSCircleFetch = false;
_finishedInitialDispatches = [[CKKSCondition alloc] init];
_ckdeviceIDInitialized = [[CKKSCondition alloc] init];
id<CKKSNSNotificationCenter> notificationCenter = [self.nsnotificationCenterClass defaultCenter];
secinfo("ckksaccount", "Registering with notification center [notificationCenter addObserver:self selector:@selector(notifyCKAccountStatusChange:) name:CKAccountChangedNotification object:NULL];
__weak __typeof(self) weakSelf = self;
// If this is a live server, register with notify
if(!SecCKKSTestsEnabled()) {
int token = 0;
notify_register_dispatch(kSOSCCCircleChangedNotification, &token, dispatch_get_global_queue(QOS_CLASS_UTILITY, 0), ^(int t) {
[weakSelf notifyCircleChange:nil];
});
}
// Fire off a fetch of the account status. Do not go on our local queue, because notifyCKAccountStatusChange will attempt to go back on it for thread-safety.
dispatch_async(dispatch_get_global_queue(QOS_CLASS_UTILITY, 0), ^{
__strong __typeof(self) strongSelf = weakSelf;
if(!strongSelf) {
return;
}
@autoreleasepool {
[strongSelf notifyCKAccountStatusChange:nil];
[strongSelf notifyCircleChange:nil];
[strongSelf.finishedInitialDispatches fulfill];
}
});
}
return self;
}
-(void)dealloc {
id<CKKSNSNotificationCenter> notificationCenter = [self.nsnotificationCenterClass defaultCenter];
[notificationCenter removeObserver:self];
}
-(NSString*)descriptionInternal: (NSString*) selfString {
return [NSString stringWithFormat:@"< selfString,
[self currentStatus],
self.currentCKAccountInfo,
SOSCCGetStatusDescription(self.currentCircleStatus),
self.currentAccountError ?: @""];
}
-(NSString*)description {
return [self descriptionInternal: [[self class] description]];
}
-(NSString*)debugDescription {
return [self descriptionInternal: [super description]];
}
-(dispatch_semaphore_t)notifyOnAccountStatusChange:(id<CKKSAccountStateListener>)listener {
// signals when we've successfully delivered the first account status
dispatch_semaphore_t finishedSema = dispatch_semaphore_create(0);
dispatch_async(self.queue, ^{
bool alreadyRegisteredListener = false;
NSEnumerator *enumerator = [self.changeListeners objectEnumerator];
id<CKKSAccountStateListener> value;
while ((value = [enumerator nextObject])) {
// do pointer comparison
alreadyRegisteredListener |= (value == listener);
}
if(listener && !alreadyRegisteredListener) {
NSString* queueName = [NSString stringWithFormat: @"ck-account-state-
dispatch_queue_t objQueue = dispatch_queue_create([queueName UTF8String], DISPATCH_QUEUE_SERIAL);
[self.changeListeners setObject: listener forKey: objQueue];
secinfo("ckksaccount", "adding a new listener:
// If we know the current account status, let this listener know
if(self.currentComputedAccountStatus != CKKSAccountStatusUnknown) {
secinfo("ckksaccount", "notifying new listener
dispatch_group_t g = dispatch_group_create();
if(!g) {
secnotice("ckksaccount", "Unable to get dispatch group.");
return;
}
[self _onqueueDeliverCurrentState:listener listenerQueue:objQueue oldStatus:CKKSAccountStatusUnknown group:g];
dispatch_group_notify(g, self.queue, ^{
dispatch_semaphore_signal(finishedSema);
});
} else {
dispatch_semaphore_signal(finishedSema);
}
} else {
dispatch_semaphore_signal(finishedSema);
}
});
return finishedSema;
}
- (dispatch_semaphore_t)notifyCKAccountStatusChange:(__unused id)object {
// signals when this notify is Complete, including all downcalls.
dispatch_semaphore_t finishedSema = dispatch_semaphore_create(0);
[self.container accountInfoWithCompletionHandler:^(CKAccountInfo* ckAccountInfo, NSError * _Nullable error) {
if(error) {
secerror("ckksaccount: error getting account info: dispatch_semaphore_signal(finishedSema);
return;
}
dispatch_sync(self.queue, ^{
self.firstCKAccountFetch = true;
[self _onqueueUpdateAccountState:ckAccountInfo circle:self.currentCircleStatus deliveredSemaphore:finishedSema];
});
}];
return finishedSema;
}
-(dispatch_semaphore_t)notifyCircleChange:(__unused id)object {
dispatch_semaphore_t finishedSema = dispatch_semaphore_create(0);
SOSCCStatus circleStatus = [CKKSCKAccountStateTracker getCircleStatus];
dispatch_sync(self.queue, ^{
self.firstSOSCircleFetch = true;
[self _onqueueUpdateAccountState:self.currentCKAccountInfo circle:circleStatus deliveredSemaphore:finishedSema];
});
return finishedSema;
}
// Takes the new ckAccountInfo we're moving to
-(void)_onqueueUpdateCKDeviceID: (CKAccountInfo*)ckAccountInfo {
dispatch_assert_queue(self.queue);
__weak __typeof(self) weakSelf = self;
// If we're in an account, opportunistically fill in the device id
if(ckAccountInfo.accountStatus == CKAccountStatusAvailable) {
[self.container fetchCurrentDeviceIDWithCompletionHandler:^(NSString* deviceID, NSError* ckerror) {
__strong __typeof(self) strongSelf = weakSelf;
if(!strongSelf) {
secerror("ckksaccount: Received fetchCurrentDeviceIDWithCompletionHandler callback with null AccountStateTracker");
return;
}
// Make sure you synchronize here; if we've logged out before the callback returns, don't record the result
dispatch_async(strongSelf.queue, ^{
__strong __typeof(self) innerStrongSelf = weakSelf;
if(innerStrongSelf.currentCKAccountInfo.accountStatus == CKAccountStatusAvailable) {
secnotice("ckksaccount", "CloudKit deviceID is:
innerStrongSelf.ckdeviceID = deviceID;
innerStrongSelf.ckdeviceIDError = ckerror;
[innerStrongSelf.ckdeviceIDInitialized fulfill];
} else {
// Logged out! No ckdeviceid.
secerror("ckksaccount: Logged back out but still received a fetchCurrentDeviceIDWithCompletionHandler callback");
innerStrongSelf.ckdeviceID = nil;
innerStrongSelf.ckdeviceIDError = nil;
// Don't touch the ckdeviceIDInitialized object; it should have been reset when the logout happened.
}
});
}];
} else {
// Logging out? no more device ID.
self.ckdeviceID = nil;
self.ckdeviceIDError = nil;
self.ckdeviceIDInitialized = [[CKKSCondition alloc] init];
}
}
// Pulled out for mocking purposes
+(void)fetchCirclePeerID:(void (^)(NSString* _Nullable peerID, NSError* _Nullable error))callback {
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
CFErrorRef cferror = nil;
SOSPeerInfoRef egoPeerInfo = SOSCCCopyMyPeerInfo(&cferror);
NSString* egoPeerID = egoPeerInfo ? (NSString*)CFBridgingRelease(CFRetainSafe(SOSPeerInfoGetPeerID(egoPeerInfo))) : nil;
CFReleaseNull(egoPeerInfo);
callback(egoPeerID, CFBridgingRelease(cferror));
});
}
// Takes the new ckAccountInfo we're moving to
-(void)_onqueueUpdateCirclePeerID: (SOSCCStatus)sosccstatus {
dispatch_assert_queue(self.queue);
__weak __typeof(self) weakSelf = self;
// If we're in a circle, fetch the peer id
if(sosccstatus == kSOSCCInCircle) {
[CKKSCKAccountStateTracker fetchCirclePeerID:^(NSString* peerID, NSError* error) {
__strong __typeof(self) strongSelf = weakSelf;
if(!strongSelf) {
secerror("ckksaccount: Received fetchCirclePeerID callback with null AccountStateTracker");
return;
}
dispatch_async(strongSelf.queue, ^{
__strong __typeof(self) innerstrongSelf = weakSelf;
if(innerstrongSelf.currentCircleStatus == kSOSCCInCircle) {
secnotice("ckksaccount", "Circle peerID is: // Still in circle. Proceed.
innerstrongSelf.accountCirclePeerID = peerID;
innerstrongSelf.accountCirclePeerIDError = error;
[innerstrongSelf.accountCirclePeerIDInitialized fulfill];
} else {
secerror("ckksaccount: Out of circle but still received a fetchCirclePeerID callback");
// Not in-circle. Throw away circle id.
strongSelf.accountCirclePeerID = nil;
strongSelf.accountCirclePeerIDError = nil;
// Don't touch the accountCirclePeerIDInitialized object; it should have been reset when the logout happened.
}
});
}];
} else {
// Not in-circle, reset circle ID
secnotice("ckksaccount", "out of circle( self.accountCirclePeerID = nil;
self.accountCirclePeerIDError = nil;
self.accountCirclePeerIDInitialized = [[CKKSCondition alloc] init];
}
}
- (bool)_onqueueDetermineLoggedIn:(NSError**)error {
// We are logged in if we are:
// in CKAccountStatusAvailable
// and supportsDeviceToDeviceEncryption == true
// and the iCloud account is not in grey mode
// and in circle
dispatch_assert_queue(self.queue);
if(self.currentCKAccountInfo) {
if(self.currentCKAccountInfo.accountStatus != CKAccountStatusAvailable) {
if(error) {
*error = [NSError errorWithDomain:CKKSErrorDomain
code:CKKSNotLoggedIn
description:@"iCloud account is logged out"];
}
return false;
} else if(!self.currentCKAccountInfo.supportsDeviceToDeviceEncryption) {
if(error) {
*error = [NSError errorWithDomain:CKKSErrorDomain
code:CKKSNotHSA2
description:@"iCloud account is not HSA2"];
}
return false;
} else if(!self.currentCKAccountInfo.hasValidCredentials) {
if(error) {
*error = [NSError errorWithDomain:CKKSErrorDomain
code:CKKSiCloudGreyMode
description:@"iCloud account is in grey mode"];
}
return false;
}
} else {
if(error) {
*error = [NSError errorWithDomain:CKKSErrorDomain
code:CKKSNotLoggedIn
description:@"No current iCloud account status"];
}
return false;
}
if(self.currentCircleStatus != kSOSCCInCircle) {
if(error) {
*error = [NSError errorWithDomain:(__bridge NSString*)kSOSErrorDomain
code:kSOSErrorNotInCircle
description:@"Not in circle"];
}
return false;
}
return true;
}
-(void)_onqueueUpdateAccountState:(CKAccountInfo*)ckAccountInfo circle:(SOSCCStatus)sosccstatus deliveredSemaphore:(dispatch_semaphore_t)finishedSema {
dispatch_assert_queue(self.queue);
if([self.currentCKAccountInfo isEqual: ckAccountInfo] && self.currentCircleStatus == sosccstatus) {
// no-op.
secinfo("ckksaccount", "received another notification of CK Account State dispatch_semaphore_signal(finishedSema);
return;
}
if(![self.currentCKAccountInfo isEqual: ckAccountInfo]) {
secnotice("ckksaccount", "moving to CK Account info: self.currentCKAccountInfo = ckAccountInfo;
[self _onqueueUpdateCKDeviceID: ckAccountInfo];
}
if(self.currentCircleStatus != sosccstatus) {
secnotice("ckksaccount", "moving to circle status: self.currentCircleStatus = sosccstatus;
if (sosccstatus == kSOSCCInCircle) {
[[CKKSAnalytics logger] setDateProperty:[NSDate date] forKey:CKKSAnalyticsLastInCircle];
}
[self _onqueueUpdateCirclePeerID: sosccstatus];
}
if(!self.firstSOSCircleFetch || !self.firstCKAccountFetch) {
secnotice("ckksaccount", "Haven't received updates from all sources; not passing update along: dispatch_semaphore_signal(finishedSema);
return;
}
CKKSAccountStatus oldComputedStatus = self.currentComputedAccountStatus;
NSError* error = nil;
if([self _onqueueDetermineLoggedIn:&error]) {
self.currentComputedAccountStatus = CKKSAccountStatusAvailable;
self.currentAccountError = nil;
} else {
self.currentComputedAccountStatus = CKKSAccountStatusNoAccount;
self.currentAccountError = error;
}
[self.currentComputedAccountStatusValid fulfill];
if(oldComputedStatus == self.currentComputedAccountStatus) {
secnotice("ckksaccount", "No change in computed account status: [self currentStatus],
self.currentCKAccountInfo,
SOSCCGetStatusDescription(self.currentCircleStatus));
dispatch_semaphore_signal(finishedSema);
return;
}
secnotice("ckksaccount", "New computed account status: [self currentStatus],
self.currentCKAccountInfo,
SOSCCGetStatusDescription(self.currentCircleStatus));
[self _onqueueDeliverStateChanges:oldComputedStatus deliveredSemaphore:finishedSema];
}
-(void)_onqueueDeliverStateChanges:(CKKSAccountStatus)oldStatus deliveredSemaphore:(dispatch_semaphore_t)finishedSema {
dispatch_assert_queue(self.queue);
dispatch_group_t g = dispatch_group_create();
if(!g) {
secnotice("ckksaccount", "Unable to get dispatch group.");
return;
}
NSEnumerator *enumerator = [self.changeListeners keyEnumerator];
dispatch_queue_t dq;
// Queue up the changes for each listener.
while ((dq = [enumerator nextObject])) {
id<CKKSAccountStateListener> listener = [self.changeListeners objectForKey: dq];
[self _onqueueDeliverCurrentState:listener listenerQueue:dq oldStatus:oldStatus group:g];
}
dispatch_group_notify(g, self.queue, ^{
dispatch_semaphore_signal(finishedSema);
});
}
-(void)_onqueueDeliverCurrentState:(id<CKKSAccountStateListener>)listener listenerQueue:(dispatch_queue_t)listenerQueue oldStatus:(CKKSAccountStatus)oldStatus group:(dispatch_group_t)g {
dispatch_assert_queue(self.queue);
__weak __typeof(listener) weakListener = listener;
if(listener) {
dispatch_group_async(g, listenerQueue, ^{
[weakListener ckAccountStatusChange:oldStatus to:self.currentComputedAccountStatus];
});
}
}
-(void)notifyCKAccountStatusChangeAndWaitForSignal {
dispatch_semaphore_wait([self notifyCKAccountStatusChange: nil], DISPATCH_TIME_FOREVER);
}
-(void)notifyCircleStatusChangeAndWaitForSignal {
dispatch_semaphore_wait([self notifyCircleChange: nil], DISPATCH_TIME_FOREVER);
}
-(dispatch_group_t)checkForAllDeliveries {
dispatch_group_t g = dispatch_group_create();
if(!g) {
secnotice("ckksaccount", "Unable to get dispatch group.");
return nil;
}
dispatch_sync(self.queue, ^{
NSEnumerator *enumerator = [self.changeListeners keyEnumerator];
dispatch_queue_t dq;
// Queue up the changes for each listener.
while ((dq = [enumerator nextObject])) {
id<CKKSAccountStateListener> listener = [self.changeListeners objectForKey: dq];
secinfo("ckksaccountblock", "Starting blocking for listener __weak __typeof(listener) weakListener = listener;
dispatch_group_async(g, dq, ^{
__strong __typeof(listener) strongListener = weakListener;
// Do nothing in particular. It's just important that this block runs.
secinfo("ckksaccountblock", "Done blocking for listener });
}
});
return g;
}
// This is its own function to allow OCMock to swoop in and replace the result during testing.
+(SOSCCStatus)getCircleStatus {
CFErrorRef cferror = NULL;
SOSCCStatus status = SOSCCThisDeviceIsInCircle(&cferror);
if(cferror) {
secerror("ckksaccount: error getting circle status: CFReleaseNull(cferror);
return kSOSCCError;
}
return status;
}
-(NSString*)currentStatus {
return [CKKSCKAccountStateTracker stringFromAccountStatus:self.currentComputedAccountStatus];
}
+(NSString*)stringFromAccountStatus: (CKKSAccountStatus) status {
switch(status) {
case CKKSAccountStatusUnknown: return @"account state unknown";
case CKKSAccountStatusAvailable: return @"logged in";
case CKKSAccountStatusNoAccount: return @"no account";
}
}
@end
#endif // OCTAGON