通常情況下,我們用NSUserDefaults存儲數據信息,但是對於一些私密信息,比如密碼、證書等等,就需要使用更爲安全的keychain了。keychain裏保存的信息不會因App被刪除而丟失,在用戶重新安裝App後依然有效,數據還在。
使用蘋果官方發佈的KeychainItemWrapper或者SFHFKeychainUtils很方便,後來看到 iphone使用keychain來存取用戶名和密碼 一文,覺得對了解keychain有很大的幫助,於是ARC控也嘗試了一把。
需要導入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
@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,保存密碼
- @interface WQUserDataManager : NSObject
- /**
- * @brief 存儲密碼
- *
- * @param password 密碼內容
- */
- +(void)savePassWord:(NSString *)password;
- /**
- * @brief 讀取密碼
- *
- * @return 密碼內容
- */
- +(id)readPassWord;
- /**
- * @brief 刪除密碼數據
- */
- +(void)deletePassWord;
- @end
@interface WQUserDataManager : NSObject
/**
* @brief 存儲密碼
*
* @param password 密碼內容
*/
+(void)savePassWord:(NSString *)password;
/**
* @brief 讀取密碼
*
* @return 密碼內容
*/
+(id)readPassWord;
/**
* @brief 刪除密碼數據
*/
+(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
#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
實現一個簡單的界面,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];
- }
-(IBAction)btnAciton:(id)sender
{
[WQUserDataManager savePassWord:self.textfield.text];
self.label.text = [WQUserDataManager readPassWord];
}
達到了預期的效果。