The only have instruction to ask for password. They cannot force you to do something. You do not have to give them access to your password manager.

Sure, they can't force you to do something, but they can make your entry dependent on your doing something, as long as you're not a citizen.

But they cannot go against the instruction they have. I.e. they cannot force you to defecate into your pants just to be sure you are not holding USB flash drive there. Same applies here. They can ask for password, but they cannot force you to actually enter it. Its illegal.

At which point they need to provide a tibetan keyboard; unless they'll be able to thoroughly inspect your mobile device that may not have wifi.