diff --git a/lib/keymanagers/Key.js b/lib/keymanagers/Key.js new file mode 100644 index 0000000..1f17e78 --- /dev/null +++ b/lib/keymanagers/Key.js @@ -0,0 +1,137 @@ +'use strict'; + +const { + pki: { + rsa, + publicKeyToPem, + privateKeyToPem, + publicKeyFromPem, + privateKeyFromPem, + }, + jsbn: { + BigInteger, + }, +} = require('node-forge'); + +const getKeyType = (str) => { + const matches = str.match(/(PRIVATE|PUBLIC) KEY/); + if (!matches) + return null; + return matches[1].toLowerCase(); +}; + +const keyFromPem = (pem) => { + const type = getKeyType(pem); + const isPublic = type === 'public'; + const key = isPublic ? publicKeyFromPem(pem) : privateKeyFromPem(pem); + + return { + isPublic, + key, + }; +}; + +/** + * Creates a public key from modulus and exponent + * @param {Buffer} mod - the modulus + * @param {Buffer} exp - the exponent + */ +const keyFromModAndExp = (mod, exp) => { + const bnMod = new BigInteger(mod.toString('hex'), 16); + const bnExp = new BigInteger(exp.toString('hex'), 16); + + return { + key: rsa.setPublicKey(bnMod, bnExp), + isPublic: true, + }; +}; + +module.exports = class Key { + constructor({ + pem = null, mod = null, exp = null, size = 2048, + } = {}) { + // generate new private key + if (!pem && !mod && !exp) { + const keyPair = rsa.generateKeyPair(size); + + this.keyIsPublic = false; + this.privateKey = keyPair.privateKey; + this.publicKey = keyPair.publicKey; + + return; + } + + // new key from pem string + if (pem) { + const { key, isPublic } = keyFromPem(pem); + + this.keyIsPublic = isPublic; + this.privateKey = isPublic ? null : key; + this.publicKey = isPublic ? key : null; + + return; + } + + // new key from mod and exp + if (mod && exp) { + const { key, isPublic } = keyFromModAndExp(mod, exp); + + this.keyIsPublic = isPublic; + this.privateKey = isPublic ? null : key; + this.publicKey = isPublic ? key : null; + + return; + } + + // not good + throw new Error(`Can not create key without ${!mod ? 'modulus' : 'exponent'}.`); + } + + static generate(size = 2048) { + return new Key({ size }); + } + + static importKey({ mod, exp }) { + return new Key({ mod, exp }); + } + + n(to = 'buff') { + const key = this.keyIsPublic ? this.publicKey : this.privateKey; + const keyN = Buffer.from(key.n.toByteArray()); + + return to === 'hex' ? keyN.toString('hex', 1) : keyN; + } + + e(to = 'buff') { + const key = this.keyIsPublic ? this.publicKey : this.privateKey; + const eKey = Buffer.from(key.e.toByteArray()); + + return to === 'hex' + ? eKey.toString('hex') + : eKey; + } + + d() { + if (this.keyIsPublic) + throw new Error('Can not get d component out of public key.'); + + return Buffer.from(this.privateKey.d.toByteArray()); + } + + isPrivate() { + return !this.keyIsPublic; + } + + isPublic() { + return this.keyIsPublic; + } + + // eslint-disable-next-line class-methods-use-this + size() { + return 2048; + } + + toPem() { + return this.keyIsPublic ? publicKeyToPem(this.publicKey) : privateKeyToPem(this.privateKey); + } +}