通常情况下,我们用NSUserDefaults存储数据信息,但是对于一些私密信息,比如密码、证书等等,就需要使用更为安全的keychain了。keychain里保存的信息不会因App被删除而丢失,在用户重新安装App后依然有效,数据还在。
使用苹果官方发布的KeychainItemWrapper或者SFHFKeychainUtils很方便,后来看到 iphone使用keychain来存取用户名和密码 一文,觉得对了解keychain有很大的帮助,于是ARC控也尝试了一把。
需要导入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,保存密码
- @interface WQUserDataManager : NSObject
- /**
- * @brief 存储密码
- *
- * @param password 密码内容
- */
- +(void)savePassWord:(NSString *)password;
- /**
- * @brief 读取密码
- *
- * @return 密码内容
- */
- +(id)readPassWord;
- /**
- * @brief 删除密码数据
- */
- +(void)deletePassWord;
- @end
@interface WQUserDataManager : NSObject
/**
* @brief 存储密码
*
* @param password 密码内容
*/
+(void)savePassWord:(NSString *)password;
/**
* @brief 读取密码
*
* @return 密码内容
*/
+(id)readPassWord;
/**
* @brief 删除密码数据
*/
+(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
实现一个简单的界面,把设定的密码存起来,然后立即读取显示出来看看效果
- -(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];
}
达到了预期的效果。