Ethereum-rsa NPM

ethereum-rsa

npm

Encrypt and Decrypt message using Ethereum keys.

How it works?

Let's say, Alice wants to send secured message to Bob. This is How it will work:

Alice encrypt message using his privatekey and Bob's publickey.
Alice sends encrypted message to Bob.
Bob decrypt message using his privatekey and Alice publickey.

Benifits:

Only Bob can read the message
Bob can be sure that the message really comes from Alice

Installation

npm install ethereum-rsa --save

Initialization

const EthRSA = require('ethereum-rsa');

Retrive PublicKey from PrivateKey:

This function will return the uncompressed publicKey from privateKey.

let publicKey = EthRSA.publicKeyByPrivateKey("4a2e11580d318f86079775229a377194d3629bb8448dfbfb8352d0cc4fc3f008");

console.log(publicKey);

Output:

04de9432ee891cbc70ff41acbcb253d06317703e943de2f2cb7aaae71dfa91ba0d8c4ed05dc7a6b804134b9225a539699bedb222e73900ebeea3bbf4161045f007

Encryption of Message:

Encrypt the message using sender's private key and recipient public key.

Parameters:

message: Message in plain text.
senderPrivateKey: Private key of the sender.
recipientPublicKey: Public key of the recipient. Public key should be in uncompressed format & 04 attached at left.

API:

EthRSA.encryptMessage(message, senderPrivateKey, recipientPublicKey);

Example:

EthRSA.encryptMessage(
    "Hey There!",
    "4a2e11580d318f86079775229a377194d3629bb8448dfbfb8352d0cc4fc3f008",
    "044f93e10b7a052260c4686dbfca7ac09d5d830c01bfe544b92438f65ebf961d64acf9992fd70565920f303bca209f7a4a96f10510a2ed0922485b4758cc2b180a"
)
.then(console.log);

Output:

br+Tol1WJkejU+rvUCm7dGm2IeOLF/SiMOi3i3Ho3G4=

Decryption of Message:

Decrypt the message using sender's public key and recipient private key. Here public key should be in uncompressed format & with 04 attached left side.

Parameters:

cipherText: Encrypted message.
recipientPrivateKey: Private key of the recipient.
senderPublicKey: Public key of the sender. Public key should be in uncompressed format & 04 attached at left.

API:

EthRSA.decryptMessage(cipherText, recipientPrivateKey, senderPublicKey);

Example:

EthRSA.decryptMessage(
    "br+Tol1WJkejU+rvUCm7dGm2IeOLF/SiMOi3i3Ho3G4=",
    "e4a2d1f1568c1eb7ffacdbaea7607d9e768fd3d3d97ec5119ccf5d8bb6c0e613",
    "04de9432ee891cbc70ff41acbcb253d06317703e943de2f2cb7aaae71dfa91ba0d8c4ed05dc7a6b804134b9225a539699bedb222e73900ebeea3bbf4161045f007"
)
.then(console.log);