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final class: KeyProtector [javadoc | source]
This is an implementation of a Sun proprietary, exportable algorithm intended for use when protecting (or recovering the cleartext version of) sensitive keys. This algorithm is not intended as a general purpose cipher. This is how the algorithm works for key protection: p - user password s - random salt X - xor key P - to-be-protected key Y - protected key R - what gets stored in the keystore Step 1: Take the user's password, append a random salt (of fixed size) to it, and hash it: d1 = digest(p, s) Store d1 in X. Step 2: Take the user's password, append the digest result from the previous step, and hash it: dn = digest(p, dn-1). Store dn in X (append it to the previously stored digests). Repeat this step until the length of X matches the length of the private key P. Step 3: XOR X and P, and store the result in Y: Y = X XOR P. Step 4: Store s, Y, and digest(p, P) in the result buffer R: R = s + Y + digest(p, P), where "+" denotes concatenation. (NOTE: digest(p, P) is stored in the result buffer, so that when the key is recovered, we can check if the recovered key indeed matches the original key.) R is stored in the keystore. The protected key is recovered as follows: Step1 and Step2 are the same as above, except that the salt is not randomly generated, but taken from the result R of step 4 (the first length(s) bytes). Step 3 (XOR operation) yields the plaintext key. Then concatenate the password with the recovered key, and compare with the last length(digest(p, P)) bytes of R. If they match, the recovered key is indeed the same key as the original key.
 public KeyProtector(char[] password) throws NoSuchAlgorithmException 
    Creates an instance of this class, and initializes it with the given password.

    The password is expected to be in printable ASCII. Normal rules for good password selection apply: at least seven characters, mixed case, with punctuation encouraged. Phrases or words which are easily guessed, for example by being found in dictionaries, are bad.

Method from sun.security.provider.KeyProtector Summary:
finalize,   protect,   recover
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from sun.security.provider.KeyProtector Detail:
 protected  void finalize() 
    Ensures that the password bytes of this key protector are set to zero when there are no more references to it.
 public byte[] protect(Key key) throws KeyStoreException 
 public Key recover(EncryptedPrivateKeyInfo encrInfo) throws UnrecoverableKeyException