Ensures auth check doesn't pass erroneously when the client-supplied digest is shorter than the correct digest, but happens to match a prefix of the correct value (e.g., same username + certain substrings of the password).
Ensures auth check doesn't pass erroneously when the client-supplied digest is shorter than the correct digest, but happens to match a prefix of the correct value (e.g., same username + certain substrings of the password).