Do java.security.Key.getEncoded() returns data in DER encoded format?
If not, is there a method that do?
UPDATE: A Key interface holding an RSA private key implementation
Do java.security.Key.getEncoded() returns data in DER encoded format?
If not, is there a method that do?
UPDATE: A Key interface holding an RSA private key implementation
Depending on the type of key. Most symmetric keys return raw bytes with no encoding. Most public keys uses ASN.1/DER encoding.
You shouldn't care about how the key is encoded. Treat getEncoded as serialization function. It returns byte-stream representation of the key, which can be saved and converted back into the key later.
For RSA private keys, it's may be encoded as PKCS#1 or PKCS#8. PKCS#1 is the preferred encoding because it contains extra CRT parameters which speed up private key operations.
Sun JCE always generates key pairs in PKCS#1 encoding so the private key is always encoded in this format defined in PKCS#1,
--
-- Representation of RSA private key with information for the CRT algorithm.
--
RSAPrivateKey ::= SEQUENCE {
version Version,
modulus INTEGER, -- n
publicExponent INTEGER, -- e
privateExponent INTEGER, -- d
prime1 INTEGER, -- p
prime2 INTEGER, -- q
exponent1 INTEGER, -- d mod (p-1)
exponent2 INTEGER, -- d mod (q-1)
coefficient INTEGER, -- (inverse of q) mod p
otherPrimeInfos OtherPrimeInfos OPTIONAL
}
Version ::= INTEGER { two-prime(0), multi(1) }
(CONSTRAINED BY {-- version must be multi if otherPrimeInfos present --})
OtherPrimeInfos ::= SEQUENCE SIZE(1..MAX) OF OtherPrimeInfo
OtherPrimeInfo ::= SEQUENCE {
prime INTEGER, -- ri
exponent INTEGER, -- di
coefficient INTEGER -- ti
}