(Perl) Verify JWT with EdDSA / Ed25519 Signature

Note: This example requires Chilkat v9.5.0.84 or greater.

Demonstrates how to verify a JWT that was signed using an Ed25519 private key.

This example verifies the EdDSA signature. It also does the following:

• Checks to see if the time constraints ("nbf" and "exp") are valid.
• Recovers the original JOSE header.
• Recovers the original data.

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use chilkat();

# Demonstrates how to verify a JWT with an EdDSA/Ed25519 Signature
# *** Requires Chilkat v9.5.0.84 or greater.

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

# Use this Ed25519 public key for verification

$jsonPubKey = "{\"kty\": \"OKP\",\"alg\": \"EdDSA\",\"crv\": \"Ed25519\",\"x\": \"11qYAYKxCrfVS_7TyWQHOg7hcvPapiMlrwIaaPcHURo\"}";

$pubKey = chilkat::CkPublicKey->new();
$success = $pubKey->LoadFromString($jsonPubKey);
if ($success == 0) {
    print $pubKey->lastErrorText() . "\r\n";
    exit;
}

$jwt = chilkat::CkJwt->new();
$token = "eyJhbGciOiJFZERTQSJ9.RXhhbXBsZSBvZiBFZDI1NTE5IHNpZ25pbmc.hgyY0il_MGCjP0JzlnLWG1PPOt7-09PGcvMg3AIbQR6dWbhijcNR4ki4iylGjg5BhVsPt9g7sVvpAr_MuM0KAg";

# First verify the signature.
$sigVerified = $jwt->VerifyJwtPk($token,$pubKey);
print "verified: " . $sigVerified . "\r\n";

if ($sigVerified == 0) {
    print $jwt->lastErrorText() . "\r\n";
    exit;
}

# Let's see if the time constraints, if any, are valid.
# The above JWT was created on the afternoon of 16-May-2016, with an expiration of 1 hour.
# If the current system time is before the "nbf" time, or after the "exp" time,
# then IsTimeValid will return false/0.
# Also, we'll allow a leeway of 60 seconds to account for any clock skew.
# Note: If the token has no "nbf" or "exp" claim fields, then IsTimeValid is always true.
$leeway = 60;
$bTimeValid = $jwt->IsTimeValid($token,$leeway);
print "time constraints valid: " . $bTimeValid . "\r\n";

# Recover the original data (the payload).
$payload = $jwt->getPayload($token);
print $payload . "\r\n";

# Recover the original JOSE header in the same way:
$joseHeader = $jwt->getHeader($token);
print $joseHeader . "\r\n";