crypto.ts

import crypto from "crypto"
import {assert} from "../utils"

export interface EncryptedString {
  data: string
  iv: string
}

export class Crypto {
  static decrypt(text: string): string {
    const ALGORITHM = "aes-256-ctr"
    const splitText = text.split(":")
    assert(splitText[0], "Missing first part of encrypted value")
    assert(splitText[1], "Missing second part of encrypted value")
    const iv = Buffer.from(splitText[0], "hex")
    const encryptionKey = process.env.DATA_ENCRYPTION_KEY
    const encryptedText = Buffer.from(splitText[1], "hex")
    const decipher = crypto.createDecipheriv(ALGORITHM, Buffer.from(encryptionKey, "hex"), iv)
    let decrypted = decipher.update(encryptedText)
    decrypted = Buffer.concat([decrypted, decipher.final()])
    return decrypted.toString()
  }

  static encrypt(text: string): string {
    const ALGORITHM = "aes-256-ctr"
    const iv = crypto.randomBytes(16)
    const encryptionKey = process.env.DATA_ENCRYPTION_KEY
    const cipher = crypto.createCipheriv(ALGORITHM, Buffer.from(encryptionKey, "hex"), iv)
    let encrypted = cipher.update(text)
    encrypted = Buffer.concat([encrypted, cipher.final()])
    return `${iv.toString("hex")}:${encrypted.toString("hex")}`
  }
}