PHP Requires Chilkat v11.0.0+

Validate JWS Using RSASSA-PKCS1-v1_5 SHA-256

See more JSON Web Signatures (JWS) Examples

Validates a JSON Web Signature (JWS) that uses RSASSA-PKCS1-v1_5 SHA-256. Chilkat2 PHP

<?php

use Chilkat2\JsonObject;
use Chilkat2\Jws;
use Chilkat2\PublicKey;
use Chilkat2\StringBuilder;

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

// This example takes a JSON signature in compact serialization format,
// and uses an RSA public key to validate and recover the protected header and payload.

// We only need a public key for signature validation.  This is the RSA public key
// that is used:

//      {"kty":"RSA",
//       "n":"ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx
//            HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs
//            D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH
//            SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV
//            MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8
//            NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ",
//       "e":"AQAB"
//      }

$sbPubKey = new StringBuilder();
$sbPubKey->Append('{"kty":"RSA",');
$sbPubKey->Append('"n":"ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx');
$sbPubKey->Append('HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs');
$sbPubKey->Append('D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH');
$sbPubKey->Append('SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV');
$sbPubKey->Append('MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8');
$sbPubKey->Append('NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ",');
$sbPubKey->Append('"e":"AQAB"');
$sbPubKey->Append('}');

$pubKey = new PublicKey();
try {
    $pubKey->LoadFromString($sbPubKey->GetAsString());

    $jws = new Jws();

    // Set the RSA public key:
    $signatureIndex = 0;
    $jws->SetPublicKey($signatureIndex, $pubKey);

    // Load the JWS.
    $sbJws = new StringBuilder();
    $sbJws->Append('eyJhbGciOiJSUzI1NiJ9');
    $sbJws->Append('.');
    $sbJws->Append('eyJpc3MiOiJqb2UiLA0KICJleHAiOjEzMDA4MTkzODAsDQogImh0dHA6Ly9leGFt');
    $sbJws->Append('cGxlLmNvbS9pc19yb290Ijp0cnVlfQ');
    $sbJws->Append('.');
    $sbJws->Append('cC4hiUPoj9Eetdgtv3hF80EGrhuB__dzERat0XF9g2VtQgr9PJbu3XOiZj5RZmh7');
    $sbJws->Append('AAuHIm4Bh-0Qc_lF5YKt_O8W2Fp5jujGbds9uJdbF9CUAr7t1dnZcAcQjbKBYNX4');
    $sbJws->Append('BAynRFdiuB--f_nZLgrnbyTyWzO75vRK5h6xBArLIARNPvkSjtQBMHlb1L07Qe7K');
    $sbJws->Append('0GarZRmB_eSN9383LcOLn6_dO--xi12jzDwusC-eOkHWEsqtFZESc6BfI7noOPqv');
    $sbJws->Append('hJ1phCnvWh6IeYI2w9QOYEUipUTI8np6LbgGY9Fs98rqVt5AXLIhWkWywlVmtVrB');
    $sbJws->Append('p0igcN_IoypGlUPQGe77Rw');

    $jws->LoadJwsSb($sbJws);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

// Validate the 1st (and only) signature at index 0..
$v = $jws->Validate($signatureIndex);
if ($v < 0) {
    // Perhaps Chilkat was not unlocked or the trial expired..
    echo "Method call failed for some other reason.\n";
    echo $jws->LastErrorText, "\n";
    exit;
}

if ($v == 0) {
    echo "Invalid signature.  The RSA key was incorrect, the JWS was invalid, or both.\n";
    exit;
}

// If we get here, the signature was validated..
echo "Signature validated.\n";
echo "--\n";

// Recover the original content:
echo "Recovered content:\n";
echo $jws->GetPayload('utf-8'), "\n";
echo "--\n";

// Examine the protected header:

$joseHeader = new JsonObject();
try {
    $jws->GetProtectedH($signatureIndex, $joseHeader);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

$joseHeader->EmitCompact = false;

echo "Protected (JOSE) header:\n";
echo $joseHeader->Emit(), "\n";

// Output:

//     Signature validated.
//     --
//     Recovered content:
//     {"iss":"joe",
//      "exp":1300819380,
//      "http://example.com/is_root":true}
//     --
//     Protected (JOSE) header:
//     {
//       "alg": "RS256"
//     }