What is ARSA?

​ ARSA is a cross-platform RSA encryption and signature library. The key and text exported can be circulated in all languages that ARSA supports.

​ Most importantly, it is incredibly easy to master with a handful of actual code.

What can ARSA do?

• Do standard RSA encryption and signature
• Encrypt long texts
• Cross platform
• One single unified format in all languages

Catalogue

1. Download and import
2. Create new ARSA keys
3. Import existed keys
4. Export keys to Strings
5. Encrypt
6. Decrypt
7. Make signatures
8. Verify signatures
9. Key objects conversion

How to use?

1. Download and import

   JAVA

   Download the source code (.java) here or install it through Maven Central:

   Gradle

   dependencies {
       implmentation 'com.atatctech:arsa:2.0.0'
   }

   Maven

   <dependency>
       <groupId>com.atatctech</groupId>
       <artifactId>arsa</artifactId>
       <version>2.0.0</version>
   </dependency>

   Then import:

   import com.atatctech.arsa.ARSA;

   Python 3+

   Download the source code (.py) here or install it through Pip:

   Windows

   pip install arsa

   Linux

   pip3 install arsa

   Then import:

   from arsa import *

2. Create new ARSA keys

   JAVA

   int keyLength;	// RSA key length, 2048 recommended
   ARSA.AKeyPair keyPair = ARSA.newkeys(keyLength);

   Get the public key:

   ARSA.APublicKey publicKey = keyPair.getPublicKey();

   Get the private key:

   ARSA.APrivateKey privateKey = keyPair.getPrivateKey();

   Python 3+

   key_pair = new_keys()

   or

   key_length: int	# RSA key length, 2048 in default
   key_pair = new_keys(key_length)

   Get the public key:

   public_key: APublicKey = key_pair.get_public_key()

   Get the private key:

   private_key: APrivateKey = key_pair.get_private_key()

3. Import existed keys

   1. Public keys

      JAVA

      String publicKeyString;
      int keyLength;
      ARSA.APublicKey publicKey = ARSA.APublicKey.importPublicKey(publicKeyString, keyLength);

      Or from java.security.PublicKey:

      PublicKey publicKeyObject;
      int keyLength;
      ARSA.APublicKey publicKey = ARSA.APublicKey.importPublicKey(publicKeyObject, keyLength);

      Python 3+

      public_key_bytes: bytes
      key_length: int
      APublicKey public_key = APublicKey.import_public_key(public_key_bytes, key_length)

   2. Private keys

      Just change every "public" above to "private".

4. Export keys to Strings

   1. Public keys

      JAVA

      ARSA.APublicKey publicKey;
      String publicKeyString = publicKey.toString();

      Python 3+

      public_key: APublicKey
      public_key_string: str = str(public_key)

   2. Private keys

      Just change every "public" above to "private".

5. Encrypt

   JAVA

   ARSA.APublicKey publicKey;
   String plainText;
   String cipherText = ARSA.encrypt(plainText, publicKey);

   Python 3+

   public_key: APublicKey
   plain_text: str
   cipher_text: bytes = encrypt(plain_text, public_key);

6. Decrypt

   JAVA

   ARSA.APrivateKey privateKey;
   String cipherText;
   String plainText = ARSA.decrypt(cipherText, privateKey);

   Python 3+

   private_key: APrivateKey
   cipher_text: base64.bytes_types
   plain_text: str = decrypt(cipher_text, private_key)

7. Make signatures

   JAVA

   String content;
   ARSA.APrivateKey privateKey;
   String signature = ARSA.sign(content, privateKey);

   Python 3+

   content: base64.bytes_types
   private_key: APrivateKey
   signature: bytes = sign(content, private_key)

8. Verify signatures

   JAVA

   String content;
   String signature;
   ARSA.APublicKey publicKey;
   boolean isQualified = ARSA.verify(content, signature, publicKey);

   Python 3+

   content: base64.bytes_types
   signature: bytes
   public_key: APublicKey
   bool is_qualified = verify(content, signature, public_key)

9. Key objects conversion

   1. JAVA

      To java.security.PublicKey:

      APublicKey publicKey;
      PublicKey publicKeyObject = publicKey.getPublicKey();

      To java.security.PrivateKey:

      APrivateKey privateKey;
      PrivateKey privateKeyObject = privateKey.getPrivateKey();

   2. Python 3+

      To Crypto.PublicKey.RSA.PublicKey:

      public_key: APublicKey
      public_key_object: PublicKey = public_key.get_public_key()

      To Crypto.PublicKey.RSA.RsaKey:

      private_key: APrivateKey
      private_key_object: RsaKey = private_key.get_private_key()