AES

Generate new key

Creating Gen Spec

Following the below compatibility table you can create a new AES key:

Block mode	Key size	Encryption padding
CBC	S128, S192, S256	PKCS7
CTR	S128, S192, S256	NONE
GCM	S128, S192, S256	NONE

val keyGenSpec = SymmetricKeyGenSpec(
    blockMode = BlockMode.GCM,
    keySize = S128,
    encryptionPadding = EncryptionPadding.NONE
)

Declaring the purposes of the key

The generating key will be used just for the specified purposes, when a purpose had not been assigned will be thrown an exception

val purposes = KeyPurposes(
    canEncrypt = true,
    canDecrypt = true
)

Generate the key

KassaforteSymmetricService.generateKey(
    alias = "toIdentifyTheKey",
    algorithm = Algorithm.AES,
    keyGenSpec = keyGenSpec,
    purposes = purposes
)

The generated key will be automatically securely stored by the library

Use the key

The methods which use the key must be executed inside a Coroutine

Encrypt

val scope = MainScope()
scope.launch {
    // data to encrypt
    val dataToEncrypt = "PLAINTEXT"

    // encrypt the data 
    val encryptedData = KassaforteSymmetricService.encrypt(
        alias = "toIdentifyTheKey",
        blockMode = BlockMode.GCM,
        padding = EncryptionPadding.NONE,
        data = encryptedData
    )

    println(encryptedData)
}

Info

The blockMode and the padding values must match the values used to generate the using key, otherwise the encryption will fail

Decrypt

val scope = MainScope()
scope.launch {
    // data to decrypt
    val dataToDecrypt = "...some encrypted data..."

    // decrypt the data 
    val decryptedData = KassaforteSymmetricService.decrypt(
        alias = "toIdentifyTheKey",
        blockMode = BlockMode.GCM,
        padding = EncryptionPadding.NONE,
        data = dataToDecrypt
    )

    println(decryptedData) // PLAINTEXT
}

Info

The blockMode and the padding values must match the values used to generate the using key, otherwise the decryption will fail

Delete a key

KassaforteSymmetricService.deleteKey(
    alias = "toIdentifyTheKey"
)

The key will be removed from the secure storage and will not more available to be used