Quote from: jackjack on June 20, 2013, 11:20:50 AM

Quote from: Qwedcxza1 on June 20, 2013, 11:08:26 AM

I'm not a programmer so it's difficult to understand this without seeing a proper mathematical description of the encryption and decryption methods.
If it uses elliptic curves then I doubt if you have reinvented EIGamal crypto system.
There are hybrid cryptosystems based on elliptic curves such as ECIES but the plain text is not required to be a point on the curve.
The problems of using elliptic curve implementations of EIGamal rather than discrete logarithm implementations relate to message expansion factors and difficulties of deterministically generating points on the curve which is why hybrid solution such as ECIES are used.
Generally I would say that home made crypto systems should be approached with caution. There are plenty of good crypto systems out there.

Let's say I want to encrypt 'hello' to your address

Quote

pubkey: your public key
privkey: your private key

I split my message in 32-char long chunks and put "0x00"s at the end of the last one to make it 32-char long too. That gives here only one chunk: 'hello---------------------------'. ('-' represents one 0x00)

Now each chunk is used as an X. Let's call the correponding point M (Two M's are possible but it doesn't matter as I never use Y)
Then I take a random N and calculate:

G*N
pubkey*N + M

Those points are the encrypted data to be sent to the recipient. As pubkey=privkey*G, M is easily calculated.

Note: Not all X values leads to a point on the EC. In such cases I just use offsets.

To be honest with you, I'm a bit busy and I haven't got time to study all of this. I'm really not knowledgeable enough to be properly commenting on this stuff anyway so I hope it does work and I'm going to retire and let you find some real experts.