Files
libcrypto/src/private-box.ts
T
2024-09-09 16:11:18 +02:00

60 lines
1.9 KiB
TypeScript

import logger from 'log'
import SecretBox from './secret-box'
import {DHusage, ecdh} from './kdf'
import {pubkey_fromString, pubkey_toString, Usage} from './misc'
import * as consts from './const'
const log = logger('crypto:private-box')
export default class PrivateBox {
private constructor(
private readonly pubkey: CryptoKey,
private readonly box: SecretBox
) {}
public static gen(extractable: boolean = true): Promise<CryptoKeyPair> {
log.trace('generate keypair')
log.trace('Extractable :', extractable)
try {
return crypto.subtle.generateKey(consts.ECDH, extractable, ['deriveKey']) as Promise<CryptoKeyPair>
} catch (e) {
log.warn('Failed to generate a key')
log.debug('Error :', e)
throw e
}
}
public static async encrypt(data: Uint8Array, pubkey: CryptoKey): Promise<PrivateBox> {
log.trace('encrypt')
const tmp_pair = await PrivateBox.gen(false)
const key = await ecdh(tmp_pair.privateKey, pubkey, DHusage.box)
const box = await SecretBox.encrypt(data, key)
return new this(tmp_pair.publicKey, box)
}
public async decrypt(privkey: CryptoKey): Promise<Uint8Array | null> {
log.trace('decrypt')
const key = await ecdh(privkey, this.pubkey, DHusage.box)
return this.box.decrypt(key)
}
public async toString(): Promise<string> {
log.trace('toString')
const pubkey = await pubkey_toString(this.pubkey)
const box = this.box.toString()
return `${pubkey}.${box}`
}
public static async fromString(data: string): Promise<PrivateBox | null> {
log.trace('fromString')
const parts = data.split('.')
if (parts.length < 2) return null
const pubkey = await pubkey_fromString(parts[0], Usage.ecdh)
if (pubkey === null) return null
const box = SecretBox.fromString(parts.slice(1).join('.'))
if (box === null) return null
return new PrivateBox(pubkey, box)
}
}