Public Private Key Generator Java

Jun 18, 2014  In Java generating public private key using RSA algorithm is quite easy as it provides lib to do these tasks. In Java java.security package contains classes to do these operation. Generating public private key pairs. By using KeyPairGenerator class we can generate public/private key.

  1. Public Private Key Encryption
  2. Rsa Public Key Generator Java
  3. Private In Java
  4. Public Private Key Generator Java Server
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In this example you will generate a public/private key pair for the Digital Signature Algorithm (DSA). You will generate keys with a 1024-bit length. Generating a key pair requires several steps: Create a Key Pair Generator. The first step is to get a key-pair generator object for generating keys for the DSA signature algorithm. Jan 24, 2017 Public key cryptography uses a pair of keys for encryption. Distribute the public key to whoever needs it but safely secure the private key. Public key cryptography can be used in two modes: Encryption: Only the private key can decrypt the data encrypted with the public key. This public and private cryptographic key pair is used during compilation to create a strong-named assembly. You can create a key pair using the Strong Name tool (Sn.exe). Key pair files usually have an.snk extension. The most popular Public Key Algorithms are RSA, Diffie-Hellman, ElGamal, DSS. Generate a Public-Private Key Pair. There are several ways to generate a Public-Private Key Pair depending on your platform. In this example, we will create a pair using Java. The Cryptographic Algorithm we will use in this example is RSA.

To sign an assembly with a strong name, you must have a public/private key pair. This public and private cryptographic key pair is used during compilation to create a strong-named assembly. You can create a key pair using the Strong Name tool (Sn.exe). Key pair files usually have an .snk extension.

Note

In Visual Studio, the C# and Visual Basic project property pages include a Signing tab that enables you to select existing key files or to generate new key files without using Sn.exe. In Visual C++, you can specify the location of an existing key file in the Advanced property page in the Linker section of the Configuration Properties section of the Property Pages window. The use of the AssemblyKeyFileAttribute attribute to identify key file pairs was made obsolete beginning with Visual Studio 2005.

Create a key pair

To create a key pair, at a command prompt, type the following command:

sn –k <file name>

In this command, file name is the name of the output file containing the key pair.

The following example creates a key pair called sgKey.snk.

If you intend to delay sign an assembly and you control the whole key pair (which is unlikely outside test scenarios), you can use the following commands to generate a key pair and then extract the public key from it into a separate file. First, create the key pair:

Next, extract the public key from the key pair and copy it to a separate file:

Once you create the key pair, you must put the file where the strong name signing tools can find it.

When signing an assembly with a strong name, the Assembly Linker (Al.exe) looks for the key file relative to the current directory and to the output directory. When using command-line compilers, you can simply copy the key to the current directory containing your code modules.

Public Private Key Encryption

If you are using an earlier version of Visual Studio that does not have a Signing tab in the project properties, the recommended key file location is the project directory with the file attribute specified as follows:

See also

This class provides the functionality of a secret (symmetric) key generator.

Key generators are constructed using one of the getInstance class methods of this class.

KeyGenerator objects are reusable, i.e., after a key has been generated, the same KeyGenerator object can be re-used to generate further keys.

There are two ways to generate a key: in an algorithm-independent manner, and in an algorithm-specific manner. The only difference between the two is the initialization of the object:

  • Algorithm-Independent Initialization

    All key generators share the concepts of a keysize and a source of randomness. There is an init method in this KeyGenerator class that takes these two universally shared types of arguments. There is also one that takes just a keysize argument, and uses the SecureRandom implementation of the highest-priority installed provider as the source of randomness (or a system-provided source of randomness if none of the installed providers supply a SecureRandom implementation), and one that takes just a source of randomness.

    Since no other parameters are specified when you call the above algorithm-independent init methods, it is up to the provider what to do about the algorithm-specific parameters (if any) to be associated with each of the keys.

  • Algorithm-Specific Initialization

    For situations where a set of algorithm-specific parameters already exists, there are two init methods that have an AlgorithmParameterSpec argument. One also has a SecureRandom argument, while the other uses the SecureRandom implementation of the highest-priority installed provider as the source of randomness (or a system-provided source of randomness if none of the installed providers supply a SecureRandom implementation).

In case the client does not explicitly initialize the KeyGenerator (via a call to an init method), each provider must supply (and document) a default initialization.

Rsa Public Key Generator Java

Every implementation of the Java platform is required to support the following standard KeyGenerator algorithms with the keysizes in parentheses:

  • AES (128)
  • DES (56)
  • DESede (168)
  • HmacSHA1
  • HmacSHA256

Private In Java

Public

Public Private Key Generator Java Server

These algorithms are described in the KeyGenerator section of the Java Cryptography Architecture Standard Algorithm Name Documentation. Consult the release documentation for your implementation to see if any other algorithms are supported.