不同應用共享資料——keychain的使用
阿新 • • 發佈:2018-12-26
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通常情況下,我們用NSUserDefaults儲存資料資訊,但是對於一些私密資訊,比如密碼、證書等等,就需要使用更為安全的keychain了。keychain裡儲存的資訊不會因App被刪除而丟失,在使用者重新安裝App後依然有效,資料還在。
使用蘋果官方釋出的KeychainItemWrapper或者SFHFKeychainUtils很方便,後來看到 iphone使用keychain來存取使用者名稱和密碼 一文,覺得對了解keychain有很大的幫助,於是ARC控也嘗試了一把。
需要匯入Security.framework
- @implementation WQKeyChain
- + (NSMutableDictionary *)getKeychainQuery:(NSString *)service {
- return [NSMutableDictionary dictionaryWithObjectsAndKeys:
- (__bridge_transfer id)kSecClassGenericPassword,(__bridge_transfer id)kSecClass,
-
service, (__bridge_transfer id)kSecAttrService,
- service, (__bridge_transfer id)kSecAttrAccount,
- (__bridge_transfer id)kSecAttrAccessibleAfterFirstUnlock,(__bridge_transfer id)kSecAttrAccessible,
- nil];
- }
- + (void)save:(NSString *)service data:(id)data {
- //Get search dictionary
-
NSMutableDictionary *keychainQuery = [self getKeychainQuery:service];
- //Delete old item before add new item
- SecItemDelete((__bridge_retained CFDictionaryRef)keychainQuery);
- //Add new object to search dictionary(Attention:the data format)
- [keychainQuery setObject:[NSKeyedArchiver archivedDataWithRootObject:data] forKey:(__bridge_transfer id)kSecValueData];
- //Add item to keychain with the search dictionary
- SecItemAdd((__bridge_retained CFDictionaryRef)keychainQuery, NULL);
- }
- + (id)load:(NSString *)service {
- id ret = nil;
- NSMutableDictionary *keychainQuery = [self getKeychainQuery:service];
- //Configure the search setting
- [keychainQuery setObject:(id)kCFBooleanTrue forKey:(__bridge_transfer id)kSecReturnData];
- [keychainQuery setObject:(__bridge_transfer id)kSecMatchLimitOne forKey:(__bridge_transfer id)kSecMatchLimit];
- CFDataRef keyData = NULL;
- if (SecItemCopyMatching((__bridge_retained CFDictionaryRef)keychainQuery, (CFTypeRef *)&keyData) == noErr) {
- @try {
- ret = [NSKeyedUnarchiver unarchiveObjectWithData:(__bridge_transfer NSData *)keyData];
- } @catch (NSException *e) {
- NSLog(@"Unarchive of %@ failed: %@", service, e);
- } @finally {
- }
- }
- return ret;
- }
- + (void)delete:(NSString *)service {
- NSMutableDictionary *keychainQuery = [self getKeychainQuery:service];
- SecItemDelete((__bridge_retained CFDictionaryRef)keychainQuery);
- }
- @end
比如,儲存密碼
- @interface WQUserDataManager : NSObject
- /**
- * @brief 儲存密碼
- *
- * @param password 密碼內容
- */
- +(void)savePassWord:(NSString *)password;
- /**
- * @brief 讀取密碼
- *
- * @return 密碼內容
- */
- +(id)readPassWord;
- /**
- * @brief 刪除密碼資料
- */
- +(void)deletePassWord;
- @end
- #import "WQUserDataManager.h"
- @implementation WQUserDataManager
- static NSString * const KEY_IN_KEYCHAIN = @"com.wuqian.app.allinfo";
- static NSString * const KEY_PASSWORD = @"com.wuqian.app.password";
- +(void)savePassWord:(NSString *)password
- {
- NSMutableDictionary *usernamepasswordKVPairs = [NSMutableDictionary dictionary];
- [usernamepasswordKVPairs setObject:password forKey:KEY_PASSWORD];
- [WQKeyChain save:KEY_IN_KEYCHAIN data:usernamepasswordKVPairs];
- }
- +(id)readPassWord
- {
- NSMutableDictionary *usernamepasswordKVPair = (NSMutableDictionary *)[WQKeyChain load:KEY_IN_KEYCHAIN];
- return [usernamepasswordKVPair objectForKey:KEY_PASSWORD];
- }
- +(void)deletePassWord
- {
- [WQKeyChain delete:KEY_IN_KEYCHAIN];
- }
- @end
實現一個簡單的介面,把設定的密碼存起來,然後立即讀取顯示出來看看效果
- -(IBAction)btnAciton:(id)sender
- {
- [WQUserDataManager savePassWord:self.textfield.text];
- self.label.text = [WQUserDataManager readPassWord];
- }