(PHP Extension) RSA Encrypt RSA/ECB/OAEPWithSHA1AndMGF1Padding

Demonstrates how to RSA encrypt using RSA/ECB/OAEPWithSHA1AndMGF1Padding. Also demonstrates RSA/ECB/OAEPWithSHA-256AndMGF1Padding. Both of these terms are from Java's JCE. Note: In this context, "ECB" doesn't actually mean anything. It's a symmetric cipher mode that doesn't apply (or make sense) in this context.

Note: This example requires Chilkat v11.0.0 or greater.

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<?php

include("chilkat.php");

$success = false;

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

$rsa = new CkRsa();

// First load a public key object with a public key.
// In this case, we'll load it from a file.
$pubkey = new CkPublicKey();
$success = $pubkey->LoadFromFile('qa_data/pem/rsa_public.pem');
if ($success == false) {
    print $pubkey->lastErrorText() . "\n";
    exit;
}

// RSA encryption is limited to small amounts of data. The limit
// is typically a few hundred bytes and is based on the key size and
// padding (OAEP vs. PKCS1_5).  RSA encryption is typically used for
// encrypting hashes or symmetric (bulk encryption algorithm) secret keys.
$plainText = 'Time is an illusion. Lunchtime doubly so.';

// Import the public key to be used for encrypting.
$success = $rsa->UsePublicKey($pubkey);

// To get OAEP padding, set the PkcsPadding property equal to false
$rsa->put_PkcsPadding(false);
$rsa->put_OaepHash('sha256');

// Indicate we'll want hex output
$rsa->put_EncodingMode('hex');

// Encrypt..
$usePrivateKey = false;
$encryptedStr = $rsa->encryptStringENC($plainText,$usePrivateKey);
print $encryptedStr . "\n";

// -------------------------------------------------
// Now decrypt with the matching private key.
$rsa2 = new CkRsa();

$privKey = new CkPrivateKey();
$success = $privKey->LoadEncryptedPem('qa_data/pem/rsa_passwd.pem','passwd');
if ($success == false) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

$success = $rsa2->UsePrivateKey($privKey);

// Make sure we have the same settings used for encryption.
$rsa2->put_PkcsPadding(false);
$rsa2->put_EncodingMode('hex');
$rsa2->put_OaepHash('sha256');

$originalStr = $rsa2->decryptStringENC($encryptedStr,true);

print $originalStr . "\n";

?>