/*
* Copyright (c) 2018 Zippie Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
/**
* @module zippie-utils/utility
*/
const secp256k1 = require('secp256k1')
const crypto = require('crypto')
const bs58 = require('bs58')
/**
* Encrypt Plaintext with Key and IV
* @param {BinaryLike} plaintext data to encrypt
* @param {CipherKey} key Private key
* @param {BinaryLike} iv Initialisation Vector
* @returns {Buffer} Encrypted Cipher text
*/
function aes128cbcEncrypt(plaintext, key, iv) {
const cipher = crypto.createCipheriv('aes-128-cbc', key, iv)
const firstChunk = cipher.update(plaintext)
const secondChunk = cipher.final()
return Buffer.concat([firstChunk, secondChunk])
}
/**
* Decrypt Ciphertext with Key and IV
* @param {BinaryLike} ciphertext
* @param {CipherKey} key
* @param {BinaryLike} iv
* @returns {Buffer} Plaintext
*/
function aes128cbcDecrypt(ciphertext, key, iv) {
const cipher = crypto.createDecipheriv('aes-128-cbc', key, iv)
const firstChunk = cipher.update(ciphertext)
const secondChunk = cipher.final()
return Buffer.concat([firstChunk, secondChunk])
}
/**
* Ensures public key parameters are in correct format.
* @private
* @param {Buffer|string} pubkey
* @returns {Buffer}
*/
function convertPublicKey (pubkey, compress = false) {
pubkey = (typeof pubkey === 'string' ? Buffer.from(pubkey, 'hex') : pubkey)
return secp256k1.publicKeyConvert(pubkey, compress)
}
/**
* Get a Cryptographically secure
* random number of byte length size
* @param {Number} size
* @returns {Buffer}
*/
function randomKey(size) {
return crypto.randomBytes(size)
}
/**
* Encodes Key and IV into a base58 string
* @param {Buffer} key
* @param {Buffer} iv
* @returns {String} keyiv
*/
function bs58KeyIvEncode(key,iv) {
const keyiv = Buffer.concat([key, iv])
const encoded = bs58.encode(keyiv)
return encoded
}
/**
* Decodes base58 string into Key and IV
* @param {String} keyiv
* @returns {Object} {key, iv}
*/
function bs58KeyIvDecode(keyiv) {
const decoded = bs58.decode(keyiv)
const key = decoded.slice(0,16)
const iv = decoded.slice(16,32)
return {key, iv}
}
module.exports = {
convertPublicKey,
aes128cbcDecrypt,
aes128cbcEncrypt,
randomKey,
bs58KeyIvEncode,
bs58KeyIvDecode
}