Perl Requires Chilkat v10.1.2+

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. Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

# 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.
my $bd = Chilkat2::BinData->new;
# In all Chilkat methods expecting a path, you can pass either absolute or relative paths.
my $success = $bd->LoadFile('rsaEncrypted/myAes.key');
if (!$success) {
    print "Failed to load the encrypted AES key.\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.
my $cert = Chilkat2::Cert->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->SmartCardPin('123456');

$success = $cert->LoadByCommonName('Test 2048 bit RSA');
if (!$success) {
    print $cert->LastErrorText, "\n";
    exit;
}

my $rsa = Chilkat2::Rsa->new;

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

# RSA Decrypt
$rsa->VerboseLogging(1);
$success = $rsa->DecryptBd($bd, 1);
if (!$success) {
    print $rsa->LastErrorText, "\n";
    exit;
}

# The contents of bd are now decrypted.
print 'Num bytes after decryption: ', $bd->NumBytes, "\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>)