2 ms·

Are you sure AES 256-bit hasn't been broken?

hello0904 2y ago
Best practices for password storage use one-way hash functions (like bcrypt, Argon2, or PBKDF2) rather than encryption algorithms like AES. AES is not one way and in theory you can generate 2nd, 3rd, etc. master keys to decrypt. :)
- ethangk 2y ago
  That’s relevant when storing a users password to verify that they’ve entered the correct data, but password managers (which Keychain effectively is, I believe) need to be able to retrieve the original password
  - hello0904 2y ago
    Frankly, you're confusing hashing algorithms, encryption and "IDs". Authentication: "Prove you are you" (hash functions) Secure Storage: "Keep this secret but let me get it back later" (encryption) Identification: "Track who/what this is" (UUIDs/tokens)
    - stouset 2y ago
      You are deeply confused as to how password managers work. Password managers—all password managers—require stored passwords to be encrypted such that they can be decrypted. Otherwise they would have no possibly way to retrieve the stored secret for the sake of submitting it to the verifying party. Best practice for verifiers is to use a one-way memory-hard password hash. Keychain is a password manager.
    - ziddoap 2y ago
      >Secure Storage: "Keep this secret but let me get it back later" (encryption) This is what keychain does. You retrieve the passwords later. So, no. It is not a one-way hash function as you stated.
- kstrauser 2y ago
  A thought experiment: Use Argon2 to hash a password before storing it in the password manager. Now the user visits that website and wants to log in. What is it that the password manager pastes into the login form? Answer: the plaintext password. But how do you get that out of the hashed value you stored earlier? You don’t. Ergo, password managers cannot use hashing functions to store their contents.
netdevnet 2y ago
They own the OS. They don't need to break it to access your passwords
- VMtest 2y ago
  I am not sure if you are ignorant or what, but GP obviously means someone else other than Apple
  - netdevnet 2y ago
    It means Apple. See: "Are you sure Apple can’t read them too?". Next time you insult someone, better use your cognition powers to avoid looking like that which you call others
    - VMtest 2y ago
      My bad, I didn't mean to insult you. I meant it as a criticism By GP, u/blitzar's comment, my cognition tells me that his comment meant anyone can break AES 256-bit encryption, including Apple, but in this context, he could have meant everyone else
threeseed 2y ago
Note that you have to break 3 independent levels of AES encryption. One for password key column, one for value column and one for the password file.

Best practices for password storage use one-way hash functions (like bcrypt, Argon2, or PBKDF2) rather than encryption algorithms like AES. AES is not one way and in theory you can generate 2nd, 3rd, etc. master keys to decrypt. :)

ethangk 2y ago
That’s relevant when storing a users password to verify that they’ve entered the correct data, but password managers (which Keychain effectively is, I believe) need to be able to retrieve the original password
- hello0904 2y ago
  Frankly, you're confusing hashing algorithms, encryption and "IDs". Authentication: "Prove you are you" (hash functions) Secure Storage: "Keep this secret but let me get it back later" (encryption) Identification: "Track who/what this is" (UUIDs/tokens)
  - stouset 2y ago
    You are deeply confused as to how password managers work. Password managers—all password managers—require stored passwords to be encrypted such that they can be decrypted. Otherwise they would have no possibly way to retrieve the stored secret for the sake of submitting it to the verifying party. Best practice for verifiers is to use a one-way memory-hard password hash. Keychain is a password manager.
  - ziddoap 2y ago
    >Secure Storage: "Keep this secret but let me get it back later" (encryption) This is what keychain does. You retrieve the passwords later. So, no. It is not a one-way hash function as you stated.
kstrauser 2y ago
A thought experiment: Use Argon2 to hash a password before storing it in the password manager. Now the user visits that website and wants to log in. What is it that the password manager pastes into the login form? Answer: the plaintext password. But how do you get that out of the hashed value you stored earlier? You don’t. Ergo, password managers cannot use hashing functions to store their contents.

netdevnet 2y ago

They own the OS. They don't need to break it to access your passwords

VMtest 2y ago
I am not sure if you are ignorant or what, but GP obviously means someone else other than Apple
- netdevnet 2y ago
  It means Apple. See: "Are you sure Apple can’t read them too?". Next time you insult someone, better use your cognition powers to avoid looking like that which you call others
  - VMtest 2y ago
    My bad, I didn't mean to insult you. I meant it as a criticism By GP, u/blitzar's comment, my cognition tells me that his comment meant anyone can break AES 256-bit encryption, including Apple, but in this context, he could have meant everyone else

threeseed 2y ago

Note that you have to break 3 independent levels of AES encryption. One for password key column, one for value column and one for the password file.