Re: What's the Difference

[Sean Mullan]

Vishal Mahajan wrote:
Axl Mattheus wrote:

Vishal,

There are different mechanisms used to encrypt/decrypt clear 
text/cipher text to wrap/unwrap a key. If one wants to encrypt 
something, one initializes the XMLCipher (javax.crypto.Cipher) to be 
in ENCRYPT_MODE in order for it to perform the appropriate 
functionality. Alternatively if one wants to wrap a key, one will 
initialize the XMLCipher to WRAP_MODE in order for it to perform the 
appropriate functionality.


Maybe I'll put my question again in other words --

       What's the difference between "wrapping a key" and "encrypting a 
key" :-\ ?
Key wrapping algorithms are especially designed to provide extra security
for encrypting and decrypting keys, as opposed to arbitrary data.
See http://www.faqs.org/rfcs/rfc3394.html for example.
--Sean

Thanks,
Vishal


Ax/

Vishal Mahajan wrote:

All,

Can someone explain what's the difference between the following two 
ways of initializing the javax.crypto.Cipher class for encrypting a 
symmetric key:

1) Cipher.init(WRAP_MODE, RSAPublicKey)

2) Cipher.init(ENCRYPT_MODE, RSAPublicKey)

I observe that XMLCipher.encryptKey() method always initializes the 
_contextCipher (javax.crypto.Cipher object) in WRAP_MODE.

Thanks in advance,
Vishal