Tech Rescue

Cryptography

Encrypt / Decrypt with AES (CCM & GCM) in Node.JS (Part 2 – Concatenate the Authentication Tag)

In the past I wrote a post about encrypting and decrypting text strings with AES in GCM and CCM mode. At the time, the demo was written to show how the algorithm works in those modes. Today I needed to handle the inclusion of such Authentication Tag inside the encrypted

Node.JS Ciphers Info in version 15.x

After the deprecation of methods createCipher(…) and createDecipher(…) due to the introduction of createCipheriv(…) and createDecipheriv(…) a lot of us had issues when specifying the keys and IVs because sometimes the key would be the incorrect size and same for the IVs. I developed a kind of brute force tester

Encrypt / Decrypt strings with RSA in Node.JS

Interesting things that go through my mind during lock-down haha! const crypto = require('crypto'); const PASSPHRASE = 'I had learned that some things are best kept secret.'; const KEY_PAIR_OPTIONS = { modulusLength: 2048, publicKeyEncoding: { type: 'spki', format: 'pem' }, privateKeyEncoding: { type: 'pkcs8', format: 'pem', cipher: 'aes-256-cbc', passphrase: PASSPHRASE } }; const KEY_PAIR

Random Password Generator in Node.JS

The other day I thought about how to generate passwords from random arrays. Here is what I came up with: /* * RaNdom Password Generator */ const crypto = require('crypto'); const PASSWORD_LENGTH = 18; const LOWERCASE_ALPHABET = 'abcdefghijklmnopqrstuvwxyz'; // 26 chars const UPPERCASE_ALPHABET = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'; // 26 chars const NUMBERS = '0123456789'; // 10 chars const SYMBOLS

How to Encrypt / Decrypt with AES (CCM & GCM) in Node.JS

First of all we have to understand what is CCM mode and GCM mode. Roughly: CCM CCM mode (Counter with CBC-MAC) is a mode of operation for cryptographic block ciphers. It is an authenticated encryption algorithm designed to provide both authentication and confidentiality. CCM mode is only defined for block

How to Sign data and Verify signature in Node.JS

Another example that occurred to me. Very useful. What will we need? * Private key in PEM format * Public key in PEM format To get those you will have use OpenSSL, please take a look at this post How to generate RSA public and private keys with OpenSSL. For this example

How to generate RSA public and private keys with OpenSSL

Before anything, I assume that you already have OpenSSL installed in your PC. In case you don’t and you are a Windows you can download it from this URLs: * http://slproweb.com/products/Win32OpenSSL.html * http://gnuwin32.sourceforge.net/packages/openssl.htm I personally used the first one. After