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Lua Requires Chilkat v11.0.0+

Duplicate PHP RSA Encryption

See more RSA Examples

Demonstrates how to duplicate the following PHP function.

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Lua
local chilkat = require("chilkat")

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

-- Duplicate the following PHP code:
--
--    public function encryptRSA($plainText,$rsaMOD,$pubKEY){
--         $rsa  = new RSA();
--         $rsa->setEncryptionMode(RSA::ENCRYPTION_PKCS1);
--         $publicKey = [
--             'e' => new BigInteger($pubKEY,16),
--             'n' => new BigInteger($rsaMOD,16)
--         ];
--
--         $rsa->loadKey($publicKey);
--         $ciphertext = $rsa->encrypt($plainText);
--         return bin2hex($ciphertext);
--     }
--
--     $plainText="key=abcdefghijkmnopq&iv=abcdefghijkmnopq&h=12345678&s=12345678"
--     $rsaMOD="F0946D8F05604809E24B8CFFD30349CEA9E5F4D320BFD9E9AA1B088863F02C43E7997D37A3E27B4F8F359F1744DB6B20A437067C0D325A80660D12FF56A57673"
--     $pubKEY="010001"

-- We have the RSA modulus in hex
local rsaMOD = "F0946D8F05604809E24B8CFFD30349CEA9E5F4D320BFD9E9AA1B088863F02C43E7997D37A3E27B4F8F359F1744DB6B20A437067C0D325A80660D12FF56A57673"

-- The RSA exponent in hex is "010001", which is 65537 in decimal.  It's typically the exponent that is always used.
local rsaEXP = "010001"

-- Get the RSA modulus and exponent in base64.
local bdMod = chilkat.BinData.new()
local bdExp = chilkat.BinData.new()
local success = bdMod:append_encoded(rsaMOD, "hex")
success = bdExp:append_encoded(rsaEXP, "hex")

-- Build the XML representation of the RSA public key
local xml = chilkat.Xml.new()
xml.tag = "RSAPublicKey"
xml:update_child_content("Modulus", bdMod:get_encoded("base64"))
xml:update_child_content("Exponent", bdExp:get_encoded("base64"))

-- Load the RSA public key into a Chilkat public key object.
local pubkey = chilkat.PublicKey.new()
success = pubkey:load_from_string(xml:get_xml())

-- Setup the RSA object for encryption and do it..
local rsa = chilkat.Rsa.new()
rsa.verbose_logging = true
success = rsa:use_public_key(pubkey)

-- Use PKCSv1.5 padding
rsa.pkcs_padding = true

-- Encrypt and return the string as hex.
rsa.encoding_mode = "hex"
local plainText = "key=abcdefghijkmnopq&iv=abcdefghijkmnopq&h=12345678&s=12345678"
local cipherText = rsa:encrypt_string_enc(plainText, false)
if not rsa.last_method_success then
    print(rsa.last_error_text)
    return
end

-- Note: The PKCSv1_5 padding incorporates random bytes.  Therefore, the RSA encryption will produce different results each time -- all of which are valid
-- and decrypt correctly to the same original text.
print(cipherText)