fn pad_key(key_bytes: &mut Vec<u8>, min_length: usize)Expand description
Pad a key to a minimum length using PKCS7-like padding. The last N bytes of the padded bytes all have the value N. For example, padded to size 4, the value 0,0 becomes 0,0,2,2.
Keys that have the type SymmetricCryptoKey::XChaCha20Poly1305Key must be distinguishable from SymmetricCryptoKey::Aes256CbcHmacKey keys, when both are encoded as byte arrays with no additional content format included in the encoding message. For this reason, the padding is used to make sure that the byte representation uniquely separates the keys by size of the byte array. The previous key types SymmetricCryptoKey::Aes256CbcHmacKey and SymmetricCryptoKey::Aes256CbcKey are 64 and 32 bytes long respectively.