Re: [Cryptography] Elliptic curve question

2013-10-10 Thread Lodewijk andré de la porte
2013/10/10 Phillip Hallam-Baker > The original author was proposing to use the same key for encryption and > signature which is a rather bad idea. > Explain why, please. It might expand the attack surface, that's true. You could always add a signed message that says "I used a key named 'Z' for

Re: [Cryptography] Elliptic curve question

2013-10-09 Thread Phillip Hallam-Baker
On Tue, Oct 8, 2013 at 4:14 PM, James A. Donald wrote: > On 2013-10-08 03:14, Phillip Hallam-Baker wrote: > > > Are you planning to publish your signing key or your decryption key? > > Use of a key for one makes the other incompatible.� > > > Incorrect. One's public key is always an elliptic p

Re: [Cryptography] Elliptic curve question

2013-10-09 Thread James A. Donald
On 2013-10-08 03:14, Phillip Hallam-Baker wrote: Are you planning to publish your signing key or your decryption key? Use of a key for one makes the other incompatible.� Incorrect. One's public key is always an elliptic point, one's private key is always a number. Thus there is no reason

Re: [Cryptography] Elliptic curve question

2013-10-08 Thread Hanno Böck
On Mon, 7 Oct 2013 10:54:50 +0200 Lay András wrote: > I made a simple elliptic curve utility in command line PHP: > > https://github.com/LaySoft/ecc_phgp > > I know in the RSA, the sign is inverse operation of encrypt, so two > different keypairs needs for encrypt and sign. In elliptic curve >

Re: [Cryptography] Elliptic curve question

2013-10-07 Thread Dominik Schürmann
On 07.10.2013 10:54, Lay András wrote: > I made a simple elliptic curve utility in command line PHP: > > https://github.com/LaySoft/ecc_phgp > > I know in the RSA, the sign is inverse operation of encrypt, so two > different keypairs needs for encrypt and sign. In elliptic curve > cryptography,

Re: [Cryptography] Elliptic curve question

2013-10-07 Thread Phillip Hallam-Baker
On Mon, Oct 7, 2013 at 4:54 AM, Lay András wrote: > Hi! > > I made a simple elliptic curve utility in command line PHP: > > https://github.com/LaySoft/ecc_phgp > > I know in the RSA, the sign is inverse operation of encrypt, so two > different keypairs needs for encrypt and sign. In elliptic curv

[Cryptography] Elliptic curve question

2013-10-07 Thread Lay András
Hi! I made a simple elliptic curve utility in command line PHP: https://github.com/LaySoft/ecc_phgp I know in the RSA, the sign is inverse operation of encrypt, so two different keypairs needs for encrypt and sign. In elliptic curve cryptography, the sign is not the inverse operation of encrypt,