Perl Requires Chilkat v9.5.0.66+

JWE with Binary Data

See more JSON Web Encryption (JWE) Examples

Demonstrates how to create a JWE that contains a binary payload (such as a JPG image). 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 a JPG file that will be the JWE payload.
my $jpgBytes = Chilkat2::BinData->new;
my $success = $jpgBytes->LoadFile('qa_data/jpg/starfish.jpg');
# Make sure your app checks the success/failure of the call to LoadFile..
print 'Original JPG size = ', $jpgBytes->NumBytes, "\n";

my $jwe = Chilkat2::Jwe->new;

my $jweProtHdr = Chilkat2::JsonObject->new;
$jweProtHdr->AppendString('alg', 'A128KW');
$jweProtHdr->AppendString('enc', 'A128CBC-HS256');
$jwe->SetProtectedHeader($jweProtHdr);

my $aesWrappingKey = 'GawgguFyGrWKav7AX4VKUg';
$jwe->SetWrappingKey(0, $aesWrappingKey, 'base64url');

# Encrypt and return the JWE in sbJwe:
my $sbJwe = Chilkat2::StringBuilder->new;
$success = $jwe->EncryptBd($jpgBytes, $sbJwe);
if (!$success) {
    print $jwe->LastErrorText, "\n";
    exit;
}

# Show the JWE:
print $sbJwe->GetAsString(), "\n";
print 'size of JWE: ', $sbJwe->Length, "\n";

# ---------------------------------------------------------
# Decrypt to get the original JPG file..

my $jwe2 = Chilkat2::Jwe->new;
$success = $jwe2->LoadJweSb($sbJwe);
if (!$success) {
    print $jwe2->LastErrorText, "\n";
    exit;
}

# Set the AES wrap key.
$jwe2->SetWrappingKey(0, $aesWrappingKey, 'base64url');

# Decrypt.
my $jpgOriginal = Chilkat2::BinData->new;
$success = $jwe2->DecryptBd(0, $jpgOriginal);
if (!$success) {
    print $jwe2->LastErrorText, "\n";
    exit;
}

print 'Decrypted JPG size = ', $jpgOriginal->NumBytes, "\n";

# Save the decrypted JPG to a file.
$success = $jpgOriginal->WriteFile('qa_output/jwe_decrypted_starfish.jpg');

print 'success = ', ($success ? 1 : 0), "\n";

# The output of this program, when tested, was:
# Original JPG size = 6229
# eyJhbGciOiJBMTI4S1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2In0.9YFz_wteV ... 7Et3hKhpxnKEXw
# size of JWE: 8473
# Decrypted JPG size = 6229
# success = True