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AndrolGenhald
AndrolGenhald
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What you did right

You're using a library

You chose to use a library to do the encryption for you. Good job! Somehow people still screw this up. Don't be a Dave, never roll your own crypto (unless you really, really understand what you're doing).

What you did wrong

You're misusing terminology

A salt is used when hashing passwords. It must be unique per password, and thus can't be located in a config. A pepper is similar to a salt, but it's the same for each password, and so it can be located in a config. Neither of these has anything to do with encryption.

You're trying to "improve" the encryption without understanding it

Adding a unique value to each string is unnecessary because (good) encryption algorithms use initialization vectors or nonces to randomize their output when encrypting duplicate data. Halite uses XSalsa20 MACed with a keyed BLAKE2b hash. Don't try to make it better, you'll just add complexity to your implementation for no reason.

There is a legitimate reason to pad data before encrypting, and that is to hide the length of the data. Some encryption algorithms allow an attacker to determine the length of the plaintext rounded to a number of bytes, and others allow to determine the exact length of the plaintext. In this case however you should pad all data to the same length (or a multiple of the same length), and the padding needn't be random.

What you did right

You're using a library

You chose to use a library to do the encryption for you. Good job! Somehow people still screw this up. Don't be a Dave, never roll your own crypto (unless you really, really understand what you're doing).

What you did wrong

You're misusing terminology

A salt is used when hashing passwords. It must be unique per password, and thus can't be located in a config. A pepper is similar to a salt, but it's the same for each password, and so it can be located in a config. Neither of these has anything to do with encryption.

You're trying to "improve" the encryption without understanding it

Adding a unique value to each string is unnecessary because (good) encryption algorithms use initialization vectors or nonces to randomize their output when encrypting duplicate data. Halite uses XSalsa20 MACed with a keyed BLAKE2b hash. Don't try to make it better, you'll just add complexity to your implementation for no reason.

What you did right

You're using a library

You chose to use a library to do the encryption for you. Good job! Somehow people still screw this up. Don't be a Dave, never roll your own crypto (unless you really, really understand what you're doing).

What you did wrong

You're misusing terminology

A salt is used when hashing passwords. It must be unique per password, and thus can't be located in a config. A pepper is similar to a salt, but it's the same for each password, and so it can be located in a config. Neither of these has anything to do with encryption.

You're trying to "improve" the encryption without understanding it

Adding a unique value to each string is unnecessary because (good) encryption algorithms use initialization vectors or nonces to randomize their output when encrypting duplicate data. Halite uses XSalsa20 MACed with a keyed BLAKE2b hash. Don't try to make it better, you'll just add complexity to your implementation for no reason.

There is a legitimate reason to pad data before encrypting, and that is to hide the length of the data. Some encryption algorithms allow an attacker to determine the length of the plaintext rounded to a number of bytes, and others allow to determine the exact length of the plaintext. In this case however you should pad all data to the same length (or a multiple of the same length), and the padding needn't be random.

Source Link
AndrolGenhald
AndrolGenhald
  • 15.8k
  • 5
  • 46
  • 53

What you did right

You're using a library

You chose to use a library to do the encryption for you. Good job! Somehow people still screw this up. Don't be a Dave, never roll your own crypto (unless you really, really understand what you're doing).

What you did wrong

You're misusing terminology

A salt is used when hashing passwords. It must be unique per password, and thus can't be located in a config. A pepper is similar to a salt, but it's the same for each password, and so it can be located in a config. Neither of these has anything to do with encryption.

You're trying to "improve" the encryption without understanding it

Adding a unique value to each string is unnecessary because (good) encryption algorithms use initialization vectors or nonces to randomize their output when encrypting duplicate data. Halite uses XSalsa20 MACed with a keyed BLAKE2b hash. Don't try to make it better, you'll just add complexity to your implementation for no reason.