Perl

JWE using A256GCMKW

See more JSON Web Encryption (JWE) Examples

This example demonstrates creating a JCE with AES GCM key wrap. Perl

use chilkat();

$success = 0;

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

$plaintext = "My text to enrypt";

$jwe = chilkat::CkJwe->new();

# First build the JWE Protected Header: 

#         {
#             "alg": "A256GCMKW",
#             "kid": "18ec08e1-bfa9-4d95-b205-2b4dd1d4321d",
#             "tag": "kfPduVQ3T3H6vnewt--ksw",
#             "iv": "KkYT0GX_2jHlfqN_",
#             "enc": "A128CBC-HS256"
#         }

$jweProtHdr = chilkat::CkJsonObject->new();
$jweProtHdr->AppendString("alg","A256GCMKW");
# kid is optional
$jweProtHdr->AppendString("kid","18ec08e1-bfa9-4d95-b205-2b4dd1d4321d");
# tag is optional
$jweProtHdr->AppendString("tag","kfPduVQ3T3H6vnewt--ksw");
$jweProtHdr->AppendString("enc","A256GCM");
# the iv should be 16 random chars.
$prng = chilkat::CkPrng->new();
$jweProtHdr->AppendString("iv",$prng->randomString(16,1,1,1));
$jwe->SetProtectedHeader($jweProtHdr);

print "JWE Protected Header: " . $jweProtHdr->emit() . "\r\n";
print "--" . "\r\n";

# Given that we have 256-bit AES, our key should be 32 bytes.
# The ascii string here is 32 bytes, therefore the 2nd arg is "ascii" to use these
# ascii chars directly as the key.
$aesWrappingKey = "2baf4f730f5e4542b428593ef9cceb0e";
$jwe->SetWrappingKey(0,$aesWrappingKey,"ascii");

# Encrypt and return the JWE:
$strJwe = $jwe->encrypt($plaintext,"utf-8");
if ($jwe->get_LastMethodSuccess() != 1) {
    print $jwe->lastErrorText() . "\r\n";
    exit;
}

# Show the JWE we just created:
print $strJwe . "\r\n";

# Decrypt the JWE that was just produced.
# 1) Load the JWE.
# 2) Set the AES wrapping key.
# 3) Decrypt.
$jwe2 = chilkat::CkJwe->new();
$success = $jwe2->LoadJwe($strJwe);
if ($success != 1) {
    print $jwe2->lastErrorText() . "\r\n";
    exit;
}

# Set the AES wrap key.  Important to use "ascii"
$jwe2->SetWrappingKey(0,$aesWrappingKey,"ascii");

# Decrypt.
$originalPlaintext = $jwe2->decrypt(0,"utf-8");
if ($jwe2->get_LastMethodSuccess() != 1) {
    print $jwe2->lastErrorText() . "\r\n";
    exit;
}

print "original text: " . "\r\n";
print $originalPlaintext . "\r\n";