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seen Feb 24 at 17:09

Apr
24
awarded  Student
Apr
23
comment Chain several RSA encryptions without increasing the message size
@poncho: You mentioned the fact that the decryption process could be performed far more efficiently than a succession of RSA-decrypt(). Could you tell us more about that?
Apr
23
awarded  Scholar
Apr
23
accepted Chain several RSA encryptions without increasing the message size
Apr
21
comment Chain several RSA encryptions without increasing the message size
Indeed it is not required to rotate with the same RSA key as long as the derivation complies. However, in practice, it is often the case as one wants to rotate N with its own RSA key. Is it problematic to rotate with the same key without padding?
Apr
20
revised Chain several RSA encryptions without increasing the message size
added 63 characters in body
Apr
20
comment Chain several RSA encryptions without increasing the message size
As I explained in the question, rotating keys in one of the use cases (see the URL to the paper for instance).
Apr
20
awarded  Editor
Apr
20
comment Chain several RSA encryptions without increasing the message size
I have edited the question above.
Apr
20
comment Chain several RSA encryptions without increasing the message size
I have edited my question above.
Apr
20
revised Chain several RSA encryptions without increasing the message size
added 888 characters in body
Apr
20
comment Chain several RSA encryptions without increasing the message size
The same key is used for every iteration, say K: K.encrypt(K.encrypt(x)) = y, then, with the private key (or the other way around), K.decrypt(K.decrypt(y)) = x.
Apr
20
comment Chain several RSA encryptions without increasing the message size
I do not think I am trying to use RSA in a block chaining mode, at least the purpose is not to increase the security of the scheme. What I want to do is simply to be able to encrypt(encrypt(encrypt(x))) = y so that I can later do decrypt(decrypt(decrypt(y))) = x without y growing. Sorry I'm not an expert hence do not know about counter signature schemes.
Apr
20
asked Chain several RSA encryptions without increasing the message size