(Perl) RSA Decrypt using Private Key on Smartcard or USB Token via Apple Keychain

See more Apple Keychain Examples

RSA decryption using a certificate's private key located on a hardware token or smartcard via the Apple Keychain.

Note: This example requires Chilkat v10.1.2 or greater.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux

use chilkat();

# Beforehand, we generated a 256-bit AES key, RSA encrypted, and saved to a file as in this example:
# Generate a Random 256-bit AES Key and RSA Encrypt

# The RSA public key used to encrypt in the above example was obtained from the Apple Keychain
# like this:
# Export a Public Key from USB Token or Smartcard using the Apple Keychain

# This example will load the encrypted data and will RSA decrypt using the 
# private key of a certificate on a USB token (or smart card) via the Keychain.
# You can list the Keychain certificates on hardware tokens using the following example:
# Apple Keychain - List Certs on Smartcards and USB Tokens

# Get the RSA encrypted data to be decrypted.
$bd = chilkat::CkBinData->new();
# In all Chilkat methods expecting a path, you can pass either absolute or relative paths.
$success = $bd->LoadFile("rsaEncrypted/myAes.key");
if ($success == 0) {
    print "Failed to load the encrypted AES key." . "\r\n";
    exit;
}

# Load the certificate having the private key from the Apple Keychain
# On MacOS and iOS, the LoadByCommonName function will search the Apple Keychain for the matching certificate.
$cert = chilkat::CkCert->new();

# To potentially prevent the PIN dialog from being displayed,
# we'll need to provide the USB token (or smart card) PIN
# Note: It might not be possible to prevent the PIN dialog from being displayed
# 
$cert->put_SmartCardPin("123456");

$success = $cert->LoadByCommonName("Test 2048 bit RSA");
if ($success == 0) {
    print $cert->lastErrorText() . "\r\n";
    exit;
}

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

# Specify we wish to use the certificate's private key for decryption.
$success = $rsa->SetX509Cert($cert,1);
if ($success == 0) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

# RSA Decrypt
$rsa->put_VerboseLogging(1);
$success = $rsa->DecryptBd($bd,1);
if ($success == 0) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

# The contents of bd are now decrypted.
print "Num bytes after decryption: " . $bd->get_NumBytes() . "\r\n";

# Some additional notes:
# 
# If using a Yubikey token, the certificate must be installed in the Key Management slot.
# The Digital Signature slot is for RSA keys to be used for signing, 
# and the Key Management slot is for RSA keys to be used for decrypting.
# 

# If you try to use the RSA key from the Digital Signature slot, you'll get an error such as this:

# The operation couldn't be completed. 
# (OSStatus error -50 - algid:encrypt:RSA:PKCS1: algorithm not supported by the key 
# <SecKeyRef:('com.apple.pivtoken:AF7172EB60DDCBF1D28459AE24398E11') 0x600001ecca90>)