PHP ActiveX Requires Chilkat v11.0.0+

ebay: Add Digital Signature to HTTP Request

See more eBay Examples

Demonstrates how to add a digital signature to an ebay HTTP request. PHP ActiveX

<?php

$success = 0;

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

//  Note: Ebay provides a Key Management API
//  See https://developer.ebay.com/api-docs/developer/key-management/overview.html

//  The following test keys can be used: 
//  
//  Ed25519 
//  
//  Private Key:
//  
//  -----BEGIN PRIVATE KEY-----
//  MC4CAQAwBQYDK2VwBCIEIJ+DYvh6SEqVTm50DFtMDoQikTmiCqirVv9mWG9qfSnF
//  -----END PRIVATE KEY-----

$strPrivateKey = 'MC4CAQAwBQYDK2VwBCIEIJ+DYvh6SEqVTm50DFtMDoQikTmiCqirVv9mWG9qfSnF';

//  Public Key:
//  
//  -----BEGIN PUBLIC KEY-----
//  MCowBQYDK2VwAyEAJrQLj5P/89iXES9+vFgrIy29clF9CC/oPPsw3c5D0bs=
//  -----END PUBLIC KEY-----

$strPublicKey = 'MCowBQYDK2VwAyEAJrQLj5P/89iXES9+vFgrIy29clF9CC/oPPsw3c5D0bs=';

//  This example assumes you got a JWE for your given private key from the Ebay Key Management REST API.
//  This JWE is just for example:
$strJwe = 'eyJ6aXAiOiJERUYiLCJlbmMiOiJBMjU2R0NNIiwidGFnIjoiSXh2dVRMb0FLS0hlS0Zoa3BxQ05CUSIsImFsZyI6IkEyNTZHQ01LVyIsIml2IjoiaFd3YjNoczk2QzEyOTNucCJ9.2o02pR9SoTF4g_5qRXZm6tF4H52TarilIAKxoVUqjd8.3qaF0KJN-rFHHm_P.AMUAe9PPduew09mANIZ-O_68CCuv6EIx096rm9WyLZnYz5N1WFDQ3jP0RBkbaOtQZHImMSPXIHVaB96RWshLuJsUgCKmTAwkPVCZv3zhLxZVxMXtPUuJ-ppVmPIv0NzznWCOU5Kvb9Xux7ZtnlvLXgwOFEix-BaWNomUAazbsrUCbrp514GIea3butbyxXLNi6R9TJUNh8V2uan-optT1MMyS7eMQnVGL5rYBULk.9K5ucUqAu0DqkkhgubsHHw';

$sbBody = new COM("Chilkat.StringBuilder");
$sbBody->Append('{\'hello\': \'world\'}');

print 'Body of request:' . "\n";
print $sbBody->getAsString() . "\n";

//  -------------------------------------------------
//  Build the signature base string...

$sbSigBase = new COM("Chilkat.StringBuilder");

$sbSigBase->Append('\'content-digest\': sha-256=:');
$sbSigBase->Append($sbBody->getHash('sha256','base64','utf-8'));
$sbSigBase->Append(':\n');

$sbSigBase->Append('\'x-ebay-signature-key\': ');
$sbSigBase->Append($strJwe);
$sbSigBase->Append('\n');

$sbSigBase->Append('\'@method\': POST\n');

//  This is the path part of the URL without query params...
$sbSigBase->Append('\'@path\': ');
$sbSigBase->Append('/verifysignature');
$sbSigBase->Append('\n');

//  The is the domain, such as "api.ebay.com" w/ port if the port is something unusual.
//  In this example, we're testing against a local docker test server (see the info at https://developer.ebay.com/develop/guides/digital-signatures-for-apis)
//  Normally, I think it would just be "api.ebay.com" instead of "localhost:8080".
$sbSigBase->Append('\'@authority\': ');
$sbSigBase->Append('localhost:8080');
$sbSigBase->Append('\n');

$sbSigBase->Append('\'@signature-params\': ');

$sbSigInput = new COM("Chilkat.StringBuilder");
$sbSigInput->Append('(\'content-digest\' \'x-ebay-signature-key\' \'@method\' \'@path\' \'@authority\')');
$sbSigInput->Append(';created=');

$dt = new COM("Chilkat.CkDateTime");
$dt->SetFromCurrentSystemTime();
$unixTimeNow = $dt->getAsUnixTimeStr(0);
$sbSigInput->Append($unixTimeNow);

$sbSigBase->AppendSb($sbSigInput);

//  -------------------------------------------------
//  Sign the signature base string using the Ed25519 private key

$bdPrivKey = new COM("Chilkat.BinData");
$bdPrivKey->AppendEncoded($strPrivateKey,'base64');

$privKey = new COM("Chilkat.PrivateKey");
$success = $privKey->LoadAnyFormat($bdPrivKey,'');
if ($success == 0) {
    print $privKey->LastErrorText . "\n";
    exit;
}

$bdToBeSigned = new COM("Chilkat.BinData");
$bdToBeSigned->AppendSb($sbSigBase,'utf-8');

$eddsa = new COM("Chilkat.EdDSA");
$sigBase64 = $eddsa->signBdENC($bdToBeSigned,'base64',$privKey);
if ($eddsa->LastMethodSuccess == 0) {
    print $eddsa->LastErrorText . "\n";
    exit;
}

print 'sigBase64:' . "\n";
print $sigBase64 . "\n";

//  ----------------------------------------------------------
//  Send the JSON POST

$http = new COM("Chilkat.Http");

$http->SetRequestHeader('x-ebay-signature-key',$strJwe);

$sbContentDigestHdr = new COM("Chilkat.StringBuilder");
$sbContentDigestHdr->Append('sha-256=:');
$sbContentDigestHdr->Append($sbBody->getHash('sha256','base64','utf-8'));
$sbContentDigestHdr->Append(':');
$http->SetRequestHeader('Content-Digest',$sbContentDigestHdr->getAsString());

$sbSigHdr = new COM("Chilkat.StringBuilder");
$sbSigHdr->Append('sig1=:');
$sbSigHdr->Append($sigBase64);
$sbSigHdr->Append(':');
$http->SetRequestHeader('Signature',$sbSigHdr->getAsString());

$sbSigInput->Prepend('sig1=');
$http->SetRequestHeader('Signature-Input',$sbSigInput->getAsString());

//  Add this header to make eBay actually check the signature.
$http->SetRequestHeader('x-ebay-enforce-signature','true');

//  Set the OAuth2 access token to add the "Authorization: Bearer <access_token>" to the header.
$http->AuthToken = 'your_oauth2_access_token';

//  The signature base string constructed above is valid if we send this POST to "http://localhost:8080/verifysignature"
//  Normally, you'll send your POST to some api.ebay.com endpoint.
$url = 'http://localhost:8080/verifysignature';

$jsonStr = $sbBody->getAsString();
$resp = new COM("Chilkat.HttpResponse");
$success = $http->HttpStr('POST','http://localhost:8080/verifysignature',$jsonStr,'utf-8','application/json',$resp);
if ($success == 0) {
    print $http->LastErrorText . "\n";
    exit;
}

print 'Response status code: ' . $resp->StatusCode . "\n";
print 'Response body:' . "\n";
print $resp->BodyStr . "\n";

?>