The Java KeyPairGenerator class (
java.security.KeyPairGenerator
) is used to generate asymmetric encryption / decryption key pairs. An asymmetric key pair consists of two keys. The first key is typically used to encrypt data. The second key which is used to decrypt data encrypted with the first key. ![Rsa Rsa](/uploads/1/2/6/0/126084885/623016696.png)
∟ RsaKeyGenerator.java for RSA Key Generation This section describes the initial draft of a RSA public key and private key generation implementation using the java.math.BigInteger class. The first step of RSA public key encryption implementation is to write a program to generate a pair of public key and private key. RSA the Key Generation Example 1. Randomly choose two prime numbers pand q. We choose p= 11 and q= 13. Compute n= pq. We compute n= pq= 1113 = 143. RSA example with OAEP Padding and random key generation.: RSA algorithm « Security « Java Tutorial.
Public Key, Private Key Type Key Pairs
The most commonly known type of asymmetric key pair is the public key, private key type of key pair. The private key is used to encrypt data, and the public key can be used to decrypt the data again. Actually, you could also encrypt data using the public key and decrypt it using the private key.
The private key is normally kept secret, and the public key can be made publicly available. Thus, if Jack encrypts some data with his private key, everyone in possession of Jack's public key can decrypt it.
Creating a KeyPairGenerator Instance
To use the Java
KeyPairGenerator
you must first create a KeyPairGenerator
instance. Creating a KeyPairGenerator
instance is done by calling the method getInstance()
method. Here is an example of creating a Java KeyPairGenerator
instance: The
getInstance()
method takes the name of the encryption algorithm to generate the key pair for. In this example we use the name RSA
. Initializing the KeyPairGenerator
Depending on the algorithm the key pair is generated for, you may have to initialize the
KeyPairGenerator
instance. Initializing the KeyPairGenerator
is done by calling its initialize()
method. Here is an example of initializing a Java KeyPairGenerator
instance: This example initializes the
KeyPairGenerator
to generate keys of 2048 bits in size. Rsa Algorithm In C
Generating a Key Pair
To generate a
KeyPair
with a KeyPairGenerator
you call the generateKeyPair()
method. Here is an example of generating a KeyPair
with the KeyPairGenerator
: Right 1
The Java KeyGenerator class (
javax.crypto.KeyGenerator
) is used to generate symmetric encryption keys. A symmetric encryption key is a key that is used for both encryption and decryption of data, by a symmetric encryption algorithm. In this Java KeyGenerator tutorial I will show you how to generate symmetric encryption keys. Creating a KeyGenerator Instance
Before you can use the Java
KeyGenerator
class you must create a KeyGenerator
instance. You create a KeyGenerator
instance by calling the static method getInstance()
passing as parameter the name of the encryption algorithm to create a key for. Here is an example of creating a Java KeyGenerator
instance: This example creates a
KeyGenerator
instance which can generate keys for the AES encryption algorithm. Initializing the KeyGenerator
After creating the
KeyGenerator
instance you must initialize it. Initializing a KeyGenerator
instance is done by calling its init()
method. Here is an example of initializing a KeyGenerator
instance: The
KeyGenerator
init()
method takes two parameters: The bit size of the keys to generate, and a SecureRandom
that is used during key generation. Generating a Key
Once the Java
KeyGenerator
instance is initialized you can use it to generate keys. Generating a key is done by calling the KeyGenerator
generateKey()
method. Here is an example of generating a symmetric key: Rsa Algorithm Example
Right 1