title: instagram enc_password generation
body: <p>Im trying to make class for generating base64 string for instagram web auth via C#.
  as base for my code i used this node.js sample - <a href="https://github.com/FeezyHendrix/Insta-mass-account-creator/issues/140#issuecomment-601788881" rel="nofollow noreferrer">click</a>
  its looks great and work perfectly but i have no idea how realise this magic:</p>
  
  <pre><code>const key = crypto.pseudoRandomBytes(32);
  publicKey = '5a0b3cd9a12fef6c786afe28cfceef60550d27ea6657bb15be4a271eaadb0903';
  const encryptedKey = tweetnacl.sealedbox.seal(key, Buffer.from(publicKey, 'hex'));
  </code></pre>
  
  <p>for aes-256-gcm encrypting i use BouncyCastle library but cant find similar action like <code>tweetnacl.sealedbox.seal</code> 
  As I understand this action returned uint8array with encrypted publicKey</p>
  
  <pre><code>import nacl from 'tweetnacl';
  import nonceGenerator from './nonce';
  import {overheadLength} from './consts';
  import {zero} from './utils';
  
  export default function seal(m, pk){
      var c = new Uint8Array(overheadLength + m.length);
  
  //overheadLength = nacl.box.publicKeyLength + nacl.box.overheadLength;
  
      var ek = nacl.box.keyPair();
      c.set(ek.publicKey);
  
      var nonce = nonceGenerator(ek.publicKey, pk);
      var boxed = nacl.box(m, nonce, pk, ek.secretKey);
      c.set(boxed, ek.publicKey.length);
  
      zero(ek.secretKey);
  
      return c;
  };
  </code></pre>
  
  <p>it's very hard for me to do it myself, and I'd be very grateful for any help.</p>