Simple KMS Cryptor

Simple cryptor library for encrypting object using AWS KMS key

Usage Example

Prepare the config

The config is compatible directly with the AWS.KMS options as specified here:

• AWS.KMS options

Example of config:

let config = {
    region: '<your aws region here>',
    accessKeyId: '<your aws access key id here>',
    secretAccessKey: '<your aws secret access key>',
    kms: {
        KeyId: '<kms key ARN or KeyId>',
    }
}

Creating instance

const KMSCrypt = require('simple-kms-crypto');
 
let kmscrypt = new KMSCrypt(config);

Encrypting object

encrypt method will return a promise

• Encrypting plaintext to a byte array

let plaintext = 'secret text';
kmscrypt.encrypt(plaintext)
  .then(ciphertext => {
      /*
          ciphertext will be a Buffer with holding the encrypted data as byte array
      */
  })
  .catch(err => {
      /*
          encryption failed
      */
  })

• Encrypting plaintext to a byte array

let plaintext = 'secret text';
kmscrypt.encrypt(plaintext)
  .then(ciphertext => {
      /*
          ciphertext will be a Buffer with holding the encrypted data as byte array
      */
  })
  .catch(err => {
      /*
          encryption failed
      */
  })

Decrypting object

decrypt method will return a promise

• If ciphertext is a byte array

kmscrypt.decrypt(ciphertext)
    .then(plaintext => {
        /*
            plaintext is decrypted object
        */    
    })
    .catch(err => {
        /*
            decryption failed
        */
    })

• If ciphertext is base64 encoded

kmscrypt.decrypt(ciphertext, 'base64')
    .then(plaintext => {
        /*
            plaintext is decrypted object
        */    
    })
    .catch(err => {
        /*
            decryption failed
        */
    })

Methods

encrypt(plaintext, encryptionType) => Promise

• plaintext is the object to be encrypted. Supported format: string, object, number
• encryptionType: base64 | binary (default)

decrypt(ciphertext, cipherType) => Promise

• ciphertext is the encrypted data formatted as binary or base64
• cipherType is the type of ciphertext which can be base64 or binary