Perl

RSA Encrypt String to Encoded Result and Reverse

See more RSA Examples

Demonstrates how to RSA encrypt a string to a base64 encoded result, and the reverse. Perl

use chilkat();

$success = 0;

# The RSA public key is used for encryption, and the private key for decryption.

# The public key's role is to make encryption accessible to anyone while ensuring that
# only the private key holder can decrypt the messages.
# The public key is designed to be widely distributed so anyone can use it to encrypt messages
# intended for the owner of the private key.

$glob = chilkat::CkGlobal->new();
$glob->put_DefaultUtf8(1);

# Load our 2048-bit RSA public key.
$pubKey = chilkat::CkPublicKey->new();
# In all Chilkat methods expecting a path, you pass either absolute or relative paths.
$success = $pubKey->LoadFromFile("rsaKeys/myTestRsaPublic.pem");
if ($success == 0) {
    print $pubKey->lastErrorText() . "\r\n";
    exit;
}

$rsa = chilkat::CkRsa->new();

# Tell RSA to use the public key.
$rsa->UsePublicKey($pubKey);

# RSA encryption is for small amounts of data, on the order of 200 bytes or less.
# The maximum number of bytes that can be RSA encrypted depends
# on the RSA key size and padding scheme (OAEP padding vs PKCS#1 v1.5 padding).
# For specific limits, see: RSA Encryption Maximum Number of Bytes

# Encrypt the utf-8 byte representation of the string.
$rsa->put_Charset("utf-8");
$rsa->put_EncodingMode("base64");

# Be Careful when Using non-us-ascii String Literals in Source Code
$encryptedB64 = $rsa->encryptStringENC("Élève français dîne à côté d’un café où l’on sert déjà du gâteau au chocolat et des éclairs délicieux",0);

# ------------------------------------------------------------------------------------------------------------------------
# Let's decrypt, which requires the matching private key...

# Load the matching 2048-bit RSA private key.
$privKey = chilkat::CkPrivateKey->new();
$password = "secret";
$success = $privKey->LoadAnyFormatFile("rsaKeys/myTestRsaPrivate.pem",$password);
if ($success == 0) {
    print $privKey->lastErrorText() . "\r\n";
    exit;
}

# Tell the RSA object to use the private key.
$rsa->UsePrivateKey($privKey);

# Indicate that after decrypting the resultant decrypted bytes contains the utf-8 byte representation of the text.
$rsa->put_Charset("utf-8");
$rsa->put_EncodingMode("base64");
$originalText = $rsa->decryptStringENC($encryptedB64,1);
if ($success == 0) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

print "Original text = " . $originalText . "\r\n";
print "Success." . "\r\n";