Bitcoin Forum

Bitcoin => Bitcoin Technical Support => Topic started by: Was on January 11, 2016, 04:57:37 AM



Title: Public key cryptography encryption possible with RIPEMD160?
Post by: Was on January 11, 2016, 04:57:37 AM
Is it possible to encrypt a message to a public key and have it be only decrypt-able by the person that owns that bitcoin address? What about multiple addresses like PGP? Any way for someone to use the RIPEMD160 hash of their public key to encrypt the message (assuming the recipient has access to the private key?)


Title: Re: Public key cryptography encryption possible with RIPEMD160?
Post by: achow101 on January 11, 2016, 12:33:33 PM
Is it possible to encrypt a message to a public key and have it be only decrypt-able by the person that owns that bitcoin address?
Yes. It is possible to use the EC keys that are used in bitcoin for PGP like encryption.

What about multiple addresses like PGP? Any way for someone to use the RIPEMD160 hash of their public key to encrypt the message (assuming the recipient has access to the private key?)
I do not thing it would be possible or secure to encrypt something to the RIPEMD160 hash since encryption requires knowing the public key and the hash does not reveal the public key.


Title: Re: Public key cryptography encryption possible with RIPEMD160?
Post by: DannyHamilton on January 11, 2016, 12:36:14 PM
Is it possible to encrypt a message to a public key and have it be only decrypt-able by the person that owns that bitcoin address?

Yes, but it is generally a bad idea.

Any way for someone to use the RIPEMD160 hash of their public key to encrypt the message (assuming the recipient has access to the private key?)

I don't believe so.  RIPEMD160 is a hash, which means that information is lost as the input is reduced to a digest.  I don't think there's enough information left in the digest to be useful for encrypting a message that can be decrypted with the original private key.


Title: Re: Public key cryptography encryption possible with RIPEMD160?
Post by: Was on January 11, 2016, 02:37:00 PM
Is it possible to encrypt a message to a public key and have it be only decrypt-able by the person that owns that bitcoin address?

Yes, but it is generally a bad idea.


Could you elaborate on the potential security risks this may present?