(Perl) JWE with DEFLATE Compression

Demonstrates how to DEFLATE ("zip") compress the JWE payload prior to encryption.

Note: This example requires Chilkat v9.5.0.66 or greater.

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

use chilkat();

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

# Note: This example requires Chilkat v9.5.0.66 or greater.

# Create some plaintext to be encrypted.
# This example will demonstrate with and without DEFLATE (zip) compression.
$sbPlainText = chilkat::CkStringBuilder->new();
$bCrLf = 1;
$line = "Live long and prosper.";
$sbPlainText->AppendLine($line,$bCrLf);
$sbPlainText->AppendLine($line,$bCrLf);
$sbPlainText->AppendLine($line,$bCrLf);
$sbPlainText->AppendLine($line,$bCrLf);

# The text to be encrypted:
print $sbPlainText->getAsString() . "\r\n";

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

# Build the JWE Protected Header: {"alg":"A128KW","enc":"A128CBC-HS256","zip":"DEF"}
# The "zip":"DEF" parameter indicates that the plaintext payload should
# be compressed prior to encryption.
$jweProtHdr = chilkat::CkJsonObject->new();
$jweProtHdr->AppendString("alg","A128KW");
$jweProtHdr->AppendString("enc","A128CBC-HS256");
$jweProtHdr->AppendString("zip","DEF");
$jwe->SetProtectedHeader($jweProtHdr);

# Set the AES key wrap key:
$aesWrappingKey = "GawgguFyGrWKav7AX4VKUg";
$jwe->SetWrappingKey(0,$aesWrappingKey,"base64url");

# Encrypt and return the JWE in sbJweCompressed:
$sbJweCompressed = chilkat::CkStringBuilder->new();
$success = $jwe->EncryptSb($sbPlainText,"utf-8",$sbJweCompressed);
if ($success != 1) {
    print $jwe->lastErrorText() . "\r\n";
    exit;
}

# Show the compressed JWE:
print $sbJweCompressed->getAsString() . "\r\n";
print "size of compressed JWE: " . $sbJweCompressed->get_Length() . "\r\n";

# Now create a JWE without compression.
$jweProtHdr->Delete("zip");
# Make sure to update the shared protected header:
$jwe->SetProtectedHeader($jweProtHdr);

$sbJweUncompressed = chilkat::CkStringBuilder->new();
$success = $jwe->EncryptSb($sbPlainText,"utf-8",$sbJweUncompressed);
if ($success != 1) {
    print $jwe->lastErrorText() . "\r\n";
    exit;
}

# Show the uncompressed JWE:
print $sbJweUncompressed->getAsString() . "\r\n";
print "size of uncompressed JWE: " . $sbJweUncompressed->get_Length() . "\r\n";

# Decrypting is the same whether compression is used or not.
# The "zip" header in the JWE indicates that the payload should be 
# automatically decompressed (inflated) after decrypting.
$jwe2 = chilkat::CkJwe->new();
$success = $jwe2->LoadJweSb($sbJweCompressed);
if ($success != 1) {
    print $jwe2->lastErrorText() . "\r\n";
    exit;
}

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

# Decrypt (also automatically decompresses).
$sbOriginalText = chilkat::CkStringBuilder->new();
$success = $jwe2->DecryptSb(0,"utf-8",$sbOriginalText);
if ($success != 1) {
    print $jwe2->lastErrorText() . "\r\n";
    exit;
}

print "original text from compressed JWE: " . "\r\n";
print $sbOriginalText->getAsString() . "\r\n";

# -----------------------------------------------------------
# Do the same with the uncompressed JWE

$success = $jwe2->LoadJweSb($sbJweUncompressed);
if ($success != 1) {
    print $jwe2->lastErrorText() . "\r\n";
    exit;
}

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

# Decrypt.
$sbOriginalText->Clear();
$success = $jwe2->DecryptSb(0,"utf-8",$sbOriginalText);
if ($success != 1) {
    print $jwe2->lastErrorText() . "\r\n";
    exit;
}

print "original text from uncompressed JWE: " . "\r\n";
print $sbOriginalText->getAsString() . "\r\n";

# ------------------------------------------------
# The output of this example is:
# (Note: Your output data will be different because the content encryption key is randomly generated.)

# eyJhbGciOiJBMTI4S1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2IiwiemlwIjoiREVGIn0.xuW-pEAIdEUFnk10m8ocursvktO8Of9ByCCAt6LgKkkOtCWCUn1kQw.zpGj-9WVni3cQxyOuZbcGA.0hzP1myua3oYpUHwCIY_3edBUREbUpLaX6wYuJduOdI.Ppc6aEO3y3B8BJ1FKMPjlA
# size of compressed JWE: 212
# eyJhbGciOiJBMTI4S1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2In0.N4KeyC7nnSFkieJOyE24_zKeuV_m7v5UKoJb1TgV4Yc_r2RzUPNvyA.6AEdyXSCKx-iMmUJyypSLg.QpixfyrwhGpmwUDp623viik4smPav7vwPLiC2r-V-jwnSfEH3mxWu6DbrIz3mixaqATwynmEBzVPxvS9jTXpSAGCnniib4_0WoPl3r_wF5tlsKOEe--jpNso-DKd1Tp8jJxj3JkFWt3IRnUUKGj17g.sBfDwFc5fzpaI-UW8-SW4g
# size of uncompressed JWE: 303
# original text from compressed JWE: 
# Live long and prosper.
# Live long and prosper.
# Live long and prosper.
# Live long and prosper.
# 
# original text from uncompressed JWE: 
# Live long and prosper.
# Live long and prosper.
# Live long and prosper.
# Live long and prosper.
#