NSUserDefaults或钥匙串最好在iPhone应用程序中保存用户名和密码

Question

In my iphone app there is some confidential data like username, password and some urls to a webservice. Which one is better NSUserdefaults or keychain. Somebody says NSUserdefaults is insecure. Why it is insecure? and can any one give the pros and cons of each one.

Answer 1

NSUserDefaults is quite easy to use and stores one value per key only. But apparently, it is not a very secure method, as there is no encryption.

But the Keychain is secure, though it is a bit hard to code. You can refer these link to use keychain access.

http://log.scifihifi.com/post/55837387/simple-iphone-keychain-code

you can also use this library deviced by Simon

https://github.com/goosoftware/GSKeychain

I hope it helps you!!

Answer 2

可能会注意到，即使删除了应用程序，钥匙串数据也将保留，但NSUserDefaults数据将随应用程序消失（NSUserDefaults是应用程序沙箱的一部分，钥匙串是与应用程序无关的服务），这可能会很有用。

Answer 3

Anything stored in NSUserDefaults can be (relatively) easily opened and read, whether on the device or in a (non-encrypted) backup to iCloud or to a sync'd Mac.

Keychain, on the other hand, is meant for stuff like certificates and passwords . I've linked an article titled "How Not To Store Passwords in iOS" which gives a bit more useful detail, as well.

Answer 4

Keychain is way better solution, because it is more secure, but anyway, if you would save this kind of information into the NSUserDefaults, your users wouldn't feel any different. If someone would hack their device, they could get information from Keychain, the same as they would get information from UserDefaults. So this question of security is rhetoric. But anyway, the good programming style is to save this data into the Keychain!

Answer 5

I would recommend you to use Keychains. Using Keychain, you can store your password in encrypted form. Take a look at Apple's GenericKeychain sample.

NSUserDefaults is a little less secure when compared with Keychain. In NSUserDefaults data can accessed easily if the specific key is known. This is not the case in Keychain.

You can also convert NSUserDefaults to Keychains. Take a look here .