(Ruby) RSA Encrypt and Decrypt Strings

Ruby sample code to RSA public-key encrypt and decrypt strings using public and private keys.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

rsa = Chilkat::CkRsa.new()

# This example also generates the public and private
# keys to be used in the RSA encryption.
# Normally, you would generate a key pair once,
# and distribute the public key to your partner.
# Anything encrypted with the public key can be
# decrypted with the private key.  The reverse is 
# also true: anything encrypted using the private
# key can be decrypted using the public key.

# Generate a 1024-bit key.  Chilkat RSA supports
# key sizes ranging from 512 bits to 4096 bits.
success = rsa.GenerateKey(1024)
if (success != true)
    print rsa.lastErrorText() + "\n";
    exit
end

# Keys are exported in XML format:
publicKey = rsa.exportPublicKey()
privateKey = rsa.exportPrivateKey()

plainText = "Encrypting and decrypting should be easy!"

# Start with a new RSA object to demonstrate that all we
# need are the keys previously exported:
rsaEncryptor = Chilkat::CkRsa.new()

# Encrypted output is always binary.  In this case, we want
# to encode the encrypted bytes in a printable string.
# Our choices are "hex", "base64", "url", "quoted-printable".
rsaEncryptor.put_EncodingMode("hex")

# We'll encrypt with the public key and decrypt with the private
# key.  It's also possible to do the reverse.
success = rsaEncryptor.ImportPublicKey(publicKey)

usePrivateKey = false
encryptedStr = rsaEncryptor.encryptStringENC(plainText,usePrivateKey)
print encryptedStr + "\n";

# Now decrypt:
rsaDecryptor = Chilkat::CkRsa.new()

rsaDecryptor.put_EncodingMode("hex")
success = rsaDecryptor.ImportPrivateKey(privateKey)

usePrivateKey = true
decryptedStr = rsaDecryptor.decryptStringENC(encryptedStr,usePrivateKey)

print decryptedStr + "\n";