Ios Keychain在每个调用中返回不同的值
我有一个类可以将Ios Keychain在每个调用中返回不同的值,ios,objective-c,keychain,Ios,Objective C,Keychain,我有一个类可以将NSDictionary保存到钥匙链中。它工作得很好,但是当我尝试加载NSDictionary时,突然得到了nil值 这是一节课: // // KeyChainHandler.m // // #import "KeyChainHandler.h" #define IDENTIFIER @"Identifier" @interface KeyChainHandler () @property (strong, nonatomic, readwrite) NSDiction
NSDictionary
保存到钥匙链中。它工作得很好,但是当我尝试加载NSDictionary
时,突然得到了nil值
这是一节课:
//
// KeyChainHandler.m
//
//
#import "KeyChainHandler.h"
#define IDENTIFIER @"Identifier"
@interface KeyChainHandler ()
@property (strong, nonatomic, readwrite) NSDictionary *applicationData;
@end
@implementation KeyChainHandler
// Make this class a singleton
static KeyChainHandler *instance = nil;
+ (KeyChainHandler*)sharedKeyChain
{
@synchronized(self)
{
if (!instance) {
instance = [[self alloc] init];
}
}
return instance;
}
- (id)init
{
self = [super init];
if (self)
{
[self load];
}
return self;
}
- (void)saveObject:(NSDictionary*)data
{
self.applicationData = data;
[self storeDictionary:data toKeychainWithKey:IDENTIFIER];
}
- (NSDictionary*)load
{
NSDictionary *data = [KeyChainHandler dictionaryFromKeychainWithKey:IDENTIFIER];
self.applicationData = data;
return data;
}
- (void)remove
{
[self deleteDictionaryFromKeychainWithKey:IDENTIFIER];
}
- (void)storeDictionary:(NSDictionary*)data toKeychainWithKey:(NSString*)aKey
{
// serialize dict
NSData *serializedDictionary = [NSKeyedArchiver archivedDataWithRootObject:data];
// encrypt in keychain
// first, delete potential existing entries with this key (it won't auto update)
[self remove];
// setup keychain storage properties
NSDictionary *storageQuery = @{
(__bridge id)kSecAttrAccount: aKey,
(__bridge id)kSecValueData: serializedDictionary,
(__bridge id)kSecClass: (__bridge id)kSecClassGenericPassword,
(__bridge id)kSecAttrAccessible: (__bridge id)kSecAttrAccessibleWhenUnlocked
};
OSStatus osStatus = SecItemAdd((__bridge CFDictionaryRef)storageQuery, nil);
if(osStatus != noErr) {
// do someting with error
}
}
+ (NSDictionary*)dictionaryFromKeychainWithKey:(NSString *)aKey
{
// setup keychain query properties
NSDictionary *readQuery = @{
(__bridge id)kSecAttrAccount: aKey,
(__bridge id)kSecReturnData: (id)kCFBooleanTrue,
(__bridge id)kSecClass: (__bridge id)kSecClassGenericPassword
};
CFDataRef serializedDictionary = NULL;
OSStatus osStatus = SecItemCopyMatching((__bridge CFDictionaryRef)readQuery, (CFTypeRef *)&serializedDictionary);
if(osStatus == noErr) {
// deserialize dictionary
NSData *data = (__bridge NSData *)serializedDictionary;
NSDictionary *storedDictionary = [NSKeyedUnarchiver unarchiveObjectWithData:data];
return storedDictionary;
}
else {
// do something with error
return nil;
}
}
- (void)deleteDictionaryFromKeychainWithKey:(NSString*)aKey
{
// setup keychain query properties
NSDictionary *deletableItemsQuery = @{
(__bridge id)kSecAttrAccount: aKey,
(__bridge id)kSecClass: (__bridge id)kSecClassGenericPassword,
(__bridge id)kSecMatchLimit: (__bridge id)kSecMatchLimitAll,
(__bridge id)kSecReturnAttributes: (id)kCFBooleanTrue
};
CFArrayRef itemList = nil;
OSStatus osStatus = SecItemCopyMatching((__bridge CFDictionaryRef)deletableItemsQuery, (CFTypeRef *)&itemList);
// each item in the array is a dictionary
NSArray *itemListArray = (__bridge NSArray *)itemList;
for (NSDictionary *item in itemListArray) {
NSMutableDictionary *deleteQuery = [item mutableCopy];
[deleteQuery setValue:(__bridge id)kSecClassGenericPassword forKey:(__bridge id)kSecClass];
// do delete
osStatus = SecItemDelete((__bridge CFDictionaryRef)deleteQuery);
if(osStatus != noErr) {
// do something with error
}
}
}
@end
当我打印[[KeyChainHandler sharedHandler]load]时,在AppDelegate
处
我得到了正确的数据,然后在登录屏幕上再次尝试,结果得到nil
。然后,当我重新启动(仅使用CMD+R)应用程序时,我不会得到nil
,我会再次得到正确的数据
有什么问题吗?也许这是某种苹果的bug?为什么:调用
[[KeyChainHandler sharedHandler]load]代码>,该属性已在单例创建时加载,如果更改,该属性也将更新
您确实需要在remove
中将属性设置为nil
相反,只需使用:
NSDictionary *dict = [KeyChainHandler sharedKeyChain].applicationData;
注意:代码是:sharedKeyChain
,示例调用是:sharedHandler
是模拟器或设备上的错误吗?为什么这是单身?为什么会有属性applicationData
,因为它从不被访问,只被设置?它在设备上。但一个有效,另一个无效。applicationData是从另一个类访问的。啊,@接口不是问题所在。这段代码看起来不错,但你不应该忽略错误——至少要将它们打印到控制台,看看是否有问题。我想你在别的地方会有问题的。也许您正在删除应用程序中的某个位置的密钥?此外,我认为您应该始终使用kSecAttrService
,因为项目实际上是由kSecAttrService
和kSecAttrAccount
对标识的。