The private and public keys under ECDSA would not be related under another crypto scheme. If you reinterpret your ECDSA private key as a private key of a different scheme, you'll surely get an unrelated public key. It's not meaningful.
What you really want is ECIES (Elliptic Curve IES)
What you really want is ECIES (Elliptic Curve IES)
But aren't ECIES keys practically the same as ECDSA keys? isn't it just points on a curve?
So reinterpreting ECDSA keys as keys of EC encryption would work.
There are no new questions on bitcointalk (ok, perhaps a few, but not many).
This has been asked (and answered) in the past:
This has been asked (and answered) in the past:
No. Bitcoin uses ECDSA which is a digital signature algorithm not an encryption algorithm. You could use another algorithm which supports encryption however Bitcoin address is not a Public Key it is a hash of the public key. If you need to use a third party algorithm, third party software, and exchange keys directly well you might as well use something that was designed for this purpose like PGP.
There are encryption systems which can use ECC keys.
ECIES is one system:
https://en.wikipedia.org/wiki/Integrated_Encryption_Scheme
However a couple things to keep in mind. I don't know of any widely deployed open source software which uses it so you will be reinventing the wheel. Could you develop such software, extensively test it, and then ensure your recipient also has said software (doesn't do much good if the recipient isn't using it) so that you can encrypt a message using a PUBLIC KEY you obtain (not address which is a public key hash) so the recipient can decrypt it by exporting a private key from his wallet into some software he is unfamiliar with? Probably.
It wouldn't work any better than other widely deployed systems like PGP and unless you are very good you run the risk of compromise which affects both systems. I would by default be suspect of any software where I have to export one or more private keys from my wallet (that control MONEYZ) to a third party software in order to decrypt a message. Even if legit it certainly doesn't sound smart or reasonable.
ECIES is one system:
https://en.wikipedia.org/wiki/Integrated_Encryption_Scheme
However a couple things to keep in mind. I don't know of any widely deployed open source software which uses it so you will be reinventing the wheel. Could you develop such software, extensively test it, and then ensure your recipient also has said software (doesn't do much good if the recipient isn't using it) so that you can encrypt a message using a PUBLIC KEY you obtain (not address which is a public key hash) so the recipient can decrypt it by exporting a private key from his wallet into some software he is unfamiliar with? Probably.
It wouldn't work any better than other widely deployed systems like PGP and unless you are very good you run the risk of compromise which affects both systems. I would by default be suspect of any software where I have to export one or more private keys from my wallet (that control MONEYZ) to a third party software in order to decrypt a message. Even if legit it certainly doesn't sound smart or reasonable.
ok, I agree I wouldn't just put my private key in any software, but if I'm really curious about the message I'd transfer the funds to another address and then proceed to decrypt...
Adding it as a feature in the bitcoin client would be cool.
