@expressive-analytics/deep-thought-authentication/src/DTUser.ts

Typescript conversion of Deep Thought Authentication

import {DT,DTModel} from '@expressive-analytics/deep-thought-js'
const crypto = require('crypto')

const dt_password_charset = "abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789"
const dt_salt_charset = "abcdef0123456789"

export class DTUserModel extends DTModel {
  protected static $T = "user"
  protected static _strict_properties = true

  protected encryptPassword(pass:string,salt?:string){
    if(salt===undefined)
      salt = this.generateString(5,dt_password_charset)
    salt = salt.substring(0,10)
    const sha1 = crypto.createHash("sha1")
    sha1.update(pass+salt)
    return sha1.digest('hex').substring(salt.length)+salt // encrypted = tail of sha1 + salt
  }

  protected generateString(len=8,charset=dt_password_charset):string{
    let str = ""
    for(let i=0;i<len;i++){
      let n = Math.random()*charset.length
      str += charset.substring(n,1)
    }
    return str
  }

  verifyPassword(given,salt_len=5){
    const encrypted = this.$get<string>('password') // accessor returns null
    const salt = salt_len>0?encrypted.substring(encrypted.length-salt_len,salt_len):""
    const password = this.encryptPassword(given,salt)
    return encrypted===password
  }
}

export interface DTUser extends DT {
  alias: string
  created_at?: string
  created_at_ms?: number
  is_admin: number
  is_active: number
  is_deleted: number
}