PHP Extension

Ibanity HTTP Signature for XS2A, Isabel Connect, Ponto Connect

See more Ibanity Examples

Demonstrates how to add a Signature header for Ibanity HTTP requests. PHP Extension

<?php

include("chilkat.php");

$success = false;

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

// In order to sign your HTTP requests, you have to add 2 headers to the HTTP request: Digest: the digest of the request payload and Signature: the actual signature of the request. 

// POST /xs2a/customer-access-tokens HTTP/1.1
// Host: api.ibanity.com
// Content-Type: application/json
// Digest: SHA-512=z4PhNX7vuL3xVChQ1m2AB9Yg5AULVxXcg/SpIdNs6c5H0NE8XYXysP+DGNKHfuwvY7kxvUdBeoGlODJ6+SfaPg==
// Ibanity-Idempotency-Key: 61f02718-eeee-46e1-b5eb-e8fd6e799c2d
// Signature: keyId="62f02718-eeee-46e1-b5eb-e8fd6e799c2e",created=1599659223,algorithm="hs2019",headers="(request-target) host digest (created) ibanity-idempotency-key",signature="SjWJWbWN7i0...zsbM="
// 
// {"data":{"type":"customerAccessToken", "attributes":{"applicationCustomerReference":"15874569"}}}

// The payload (body) of the above HTTP request is the JSON.
// Build the JSON above.
// Use this online tool to generate code from sample JSON: 
// Generate Code to Create JSON
$json = new CkJsonObject();
$json->UpdateString('data.type','customerAccessToken');
$json->UpdateString('data.attributes.applicationCustomerReference','15874569');

$payload = $json->emit();
print 'payload = ' . $payload . "\n";

// Step 1: Build the (created) virtual header

$dtNow = new CkDateTime();
$dtNow->SetFromCurrentSystemTime();
$created = $dtNow->getAsUnixTimeStr(false);
print 'created = ' . $created . "\n";

// Step 2: Build the Digest header
$crypt = new CkCrypt2();
$crypt->put_HashAlgorithm('sha512');
$crypt->put_EncodingMode('base64');
$crypt->put_Charset('utf-8');

$sbDigestHdrValue = new CkStringBuilder();
$sbDigestHdrValue->Append('SHA-512=');
$sbDigestHdrValue->Append($crypt->hashStringENC($json->emit()));

print $sbDigestHdrValue->getAsString() . "\n";

// Step 3: Build the (request target) virtual header

// In order to build the signature you will need a virtual header named (request-target) (the parentheses are important). 
// The (request-target) is the string concatenation of the HTTP method (in lowercase) with the path and query parameters.
$request_target = 'post /xs2a/customer-access-tokens';

// Step 4: Build the signing string

// The signing string is the concatenation of the signed header names (in lowercase) and values separated by a LF.

// You must always sign the following headers: (request-target), host, (created), digest. 
// If used, you must also sign the authorization header and any ibanity-* headers, such as ibanity-idempotency-key. 

$sbSigningString = new CkStringBuilder();
$sbSigningString->Append('(request-target): ');
$sbSigningString->AppendLine($request_target,false);
$sbSigningString->Append('host: ');
$sbSigningString->AppendLine('api.ibanity.com',false);
$sbSigningString->Append('digest: ');
$sbSigningString->AppendLine($sbDigestHdrValue->getAsString(),false);
$sbSigningString->Append('(created): ');
$sbSigningString->AppendLine($created,false);
$sbSigningString->Append('ibanity-idempotency-key: ');
$idempotencyKey = $crypt->generateUuid();
$sbSigningString->Append($idempotencyKey);

// Step 5: Build the signed headers list

// To allow Ibanity to check the signed headers, you must provide a list of the header names. They should be lowercase and in the same order used to create the signing string. 
$signed_headers_list = '(request-target) host digest (created) ibanity-idempotency-key';

// Step 6: Build the Signature header

// This is where the real signing happens. The signature header is a combination of several sub-headers -
// 
//     keyId: the identifier for the application's signature certificate, obtained from the Developer Portal
//     algorithm: the digital signature algorithm used to generate the signature (must be hs2019)
//     headers: The list of HTTP headers created in step 5
//     signature: the Base64-encoded digital signature of the signing string created in step 4.

$privKey = new CkPrivateKey();
$success = $privKey->LoadEncryptedPemFile('my_ibanity_signature_private_key.pem','pem_password');
if ($success == false) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

$rsa = new CkRsa();
$rsa->put_PssSaltLen(32);
$rsa->put_EncodingMode('base64');
// Use the RSASSA-PSS signature algorithm
$rsa->put_PkcsPadding(false);

$success = $rsa->UsePrivateKey($privKey);
if ($success == false) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

// Sign the signing string.
$sigBase64 = $rsa->signStringENC($sbSigningString->getAsString(),'sha-256');
if ($rsa->get_LastMethodSuccess() == false) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

// Build the signature header value.
$sbSigHeaderValue = new CkStringBuilder();
$sbSigHeaderValue->Append('keyId=\'');
// Use your identifier for the application's signature certificate, obtained from the Developer Portal
$sbSigHeaderValue->Append('62f02718-eeee-46e1-b5eb-e8fd6e799c2e');
$sbSigHeaderValue->Append('\',created=');
$sbSigHeaderValue->Append($created);
$sbSigHeaderValue->Append(',algorithm=\'hs2019\',headers=\'');
$sbSigHeaderValue->Append($signed_headers_list);
$sbSigHeaderValue->Append('\',signature=\'');
$sbSigHeaderValue->Append($sigBase64);
$sbSigHeaderValue->Append('\'');

print $sbSigHeaderValue->getAsString() . "\n";

?>