(PHP ActiveX) Verify JWT Using an RSA Public Key (RS256, RS384, RS512)

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

This example verifies the RSA 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 claims JSON.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

// Demonstrates how to verify an JWT using an RSA public key.

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

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.PublicKey')
$pubKey = new COM("Chilkat.PublicKey");
$success = $pubKey->LoadFromFile('qa_data/pem/rsa_public.pem');

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Jwt')
$jwt = new COM("Chilkat.Jwt");

$token = 'eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJodHRwOi8vZXhhbXBsZS5vcmciLCJzdWIiOiJKb2huIiwiYXVkIjoiaHR0cDovL2V4YW1wbGUuY29tIiwiaWF0IjoxNDYzNDQ1MjM4LCJuYmYiOjE0NjM0NDUyMzgsImV4cCI6MTQ2MzQ0ODgzOH0.XRtqed6nuJ9lrp0wbNdDX3fCkSh_d9cHAniPbNcqm7G-5N3mtI5ntQvZBDP3pHtECVqufuDwW7XgUtzAi0ZXhyiRm1iZ3wMSN5lHWv52OQJmMHPA7VPd8Q1hDG-tx-QswzJKd75OEUHP7wIXq2Mg_YVElfDvJI6TGjGyS1y-RLHlz-ldlGsEwIBkO0PtzIYTVov97x8p9KCsPNhS4lZUIqKOYoTZUV5LpuAWARl-636DfMEB_A5_IEaw_W8leh2suP2ULVZxwE-Tk1kBC9tsSGrBrPTtg7sziaV4Lbb0JRANmh98uTRu5f8ji9CVOnpbMiAzjsJSy56kz_olweXSuA';

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

// 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 . "\n";

// Now let's recover the original claims JSON (the payload).
$payload = $jwt->getPayload($token);
// The payload will likely be in compact form:
print $payload . "\n";

// We can format for human viewing by loading it into Chilkat's JSON object
// and emit.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.JsonObject')
$json = new COM("Chilkat.JsonObject");
$success = $json->Load($payload);
$json->EmitCompact = 0;
print $json->emit() . "\n";

// We can recover the original JOSE header in the same way:
$joseHeader = $jwt->getHeader($token);
// The payload will likely be in compact form:
print $joseHeader . "\n";

// We can format for human viewing by loading it into Chilkat's JSON object
// and emit.
$success = $json->Load($joseHeader);
$json->EmitCompact = 0;
print $json->emit() . "\n";

?>