Encryption Snippets

You can use below code snippet to perform encryption and decryption of request and response

Javascript

const crypto = require('crypto');

const secretKey = SHARED_SECRET_KEY';

function encryption(token) {
try {
const iv = crypto.randomBytes(12);
const cipher = crypto.createCipheriv('aes-256-gcm', Buffer.from(secretKey), iv);

const encrypted = Buffer.concat([cipher.update(Buffer.from(token)), cipher.final()]);
const tag = cipher.getAuthTag();

return Buffer.concat([iv, encrypted, tag]).toString('base64');
} catch (err) {
console.error(err);
return '';
}
}

function decryption(encryptedToken) {
try {
const encryptedBuffer = Buffer.from(encryptedToken, 'base64');
const nonce = encryptedBuffer.slice(0, 12);
const ciphertext = encryptedBuffer.slice(12, -16);
const tag = encryptedBuffer.slice(-16);

const decipher = crypto.createDecipheriv('aes-256-gcm', Buffer.from(secretKey), nonce);
decipher.setAuthTag(tag);

let decrypted = decipher.update(ciphertext);
decrypted += decipher.final();

return decrypted.toString('base64');
} catch (err) {
console.error(err);
return '';
}
}

Go

func Decrypt(key []byte, payload string) ([]byte, error) {
	ciphertext, _ := base64.StdEncoding.DecodeString(payload)

	c, err := aes.NewCipher(key)
	if err != nil {
		return nil, err
	}

	gcm, err := cipher.NewGCM(c)
	if err != nil {
		return nil, err
	}

	nonceSize := gcm.NonceSize()
	if len(ciphertext) < nonceSize {
		return nil, err
	}

	nonce, ciphertext := ciphertext[:nonceSize], ciphertext[nonceSize:]
	plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
	if err != nil {
		return nil, err
	}
	return plaintext, nil
}

Python

  from Crypto.Cipher import AES
  from Crypto.Random import get_random_bytes

  nonce = get_random_bytes(12)
  cipher = AES.new(b'u8x/A?D(G+KbPeShVmYq3t6w9y$B&E)H', AES.MODE_GCM, nonce=nonce)

  import json
  import base64
  data = b'{"merchantPaymentReferenceId":"PAY-123-456","merchantOrderId":"ORD-123-456","merchantOrderDetailsUrl":"https://merchant.com/order/ORD-123-456","txnInfo":{"currency":"INR","amount":"700"},"transactionContext":"eyJmYXJlRGV0YWlscyI6eyJ0b3RhbEFtb3VudCI6IjQwMCIsInBheWFibGVBbW91bnQiOiI0MDAifSwiY2FydERldGFpbHMiOnsiY2FydEl0ZW1zIjpbeyJjYXRlZ29yeSI6IkZPT0QiLCJpdGVtSWQiOiJNRVItSVRFTS0xMDEiLCJwcmljZSI6IjQwMCIsIml0ZW1OYW1lIjoiU01PT1IiLCJxdWFudGl0eSI6MSwiYWRkaXRpb25hbEluZm8iOnsic2hpcHBpbmdJbmZvIjp7ImRlbGl2ZXJ5TG9jYXRpb24iOiJiYW5nYWxvcmUifX19XX19"}'
  cipher_text, tag = cipher.encrypt_and_digest(data)
  cipher_text = base64.b64encode(nonce+cipher_text+tag).decode('utf-8')
  print("nonce {}".format(nonce))
  print("cipher text {}".format(cipher_text))