Perl Requires Chilkat v11.5.0+

Create JWS Using Private Key on a Smart Card

See more JSON Web Signatures (JWS) Examples

Creates and validates a JSON Web Signature (JWS) using the private key associated with a certificate on a smart card. Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

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

# Load the certificate from a smart card.
my $cert = Chilkat2::Cert->new;

# Set the smarcard PIN prior to loading
$cert->SmartCardPin('123456');

# Detect the connected smartcard or USB security token and load the default certificate.
my $success = $cert->LoadFromSmartcard('');
if (!$success) {
    print $cert->LastErrorText, "\n";
    exit;
}

# Note: Chilkat provides many different ways to load a certificate from a smartcard or USB token,
# such as selecting a certificate if the card contains multiple certificates with private keys,
# or working with lower-level PKCS11 or ScMinidriver API's (both of which Chilkat provides).

# Create the JWS Protected Header
my $jwsProtHdr = Chilkat2::JsonObject->new;

if ($cert->IsEcdsa()) {
    $jwsProtHdr->AppendString('alg', 'ES256');
} else {
    $jwsProtHdr->AppendString('alg', 'RS256');
}

my $jws = Chilkat2::Jws->new;

# Set the protected header:
my $signatureIndex = 0;
$jws->SetProtectedHeader($signatureIndex, $jwsProtHdr);

# Provide the private key via the certificate.
$jws->SetSigningCert($signatureIndex, $cert);

# Set the payload.
my $bIncludeBom = 0;
my $payloadStr = 'In our village, folks say God crumbles up the old moon into stars.';
$jws->SetPayload($payloadStr, 'utf-8', $bIncludeBom);

# Create the JWS
# By default, the compact serialization is used.
my $jwsCompact = $jws->CreateJws();
if (!$jws->LastMethodSuccess) {
    print $jws->LastErrorText, "\n";
    exit;
}

print 'JWS: ', $jwsCompact, "\n";

# sample output:
# JWS: eyJhbGciOiJQUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.TRWhwRo5dMv9-8OzrInfJTwmUGYgjLfHk8lqF072ND-FmLWEBnUTOpY8oJXp8FdWw2SalbdOeNlrtlJjwk4XK8Ql2iJ_2qMCtxsvLPhKBOqFoAF4aBvTOEDVJDxf0DaBSiydEEtfTVV2iwBcjWabu5J2XieR5y7QZQtuHsn7T3qKBvCcCejN3Y2oqAT3qMHvu1fTms1r_91wBn_K7Wjd9UkZ1n02qQcUHJznR_OF2BgN7_KWIDAF9ZS9keoju2NPpPelO4yxa2XUPnehY3G7dHKoCxUEQR4d2Xc5voqDASTVCDqQS4PVOZdvT3Ein6-SanAlCwbWBbkvT8g6-5PImQ

# Now load the JWS, validate, and recover the original text.
my $jws2 = Chilkat2::Jws->new;

# Load the JWS.
$success = $jws2->LoadJws($jwsCompact);

my $pubKey = Chilkat2::PublicKey->new;
$cert->GetPublicKey($pubKey);

# Set the public key used for validation.
$signatureIndex = 0;
$jws2->SetPublicKey($signatureIndex, $pubKey);

# Validate the 1st (and only) signature at index 0..
my $v = $jws2->Validate($signatureIndex);
if ($v < 0) {
    # Perhaps Chilkat was not unlocked or the trial expired..
    print "Method call failed for some other reason.\n";
    print $jws2->LastErrorText, "\n";
    exit;
}

if ($v == 0) {
    print "Invalid signature.  The key was incorrect, the JWS was invalid, or both.\n";
    exit;
}

# If we get here, the signature was validated..
print "Signature validated.\n";

# Recover the original content:
print $jws2->GetPayload('utf-8'), "\n";

# Examine the protected header:

my $joseHeader = Chilkat2::JsonObject->new;
$success = $jws2->GetProtectedH($signatureIndex, $joseHeader);
if (!$success) {
    print $jws2->LastErrorText, "\n";
    exit;
}

$joseHeader->EmitCompact(0);

print "Protected (JOSE) header:\n";
print $joseHeader->Emit(), "\n";

# Output:

#     Signature validated.
#     In our village, folks say God crumbles up the old moon into stars.
#     Protected (JOSE) header:
#     {
#       "alg": "RS256"
#     }