(Delphi ActiveX) Ibanity HTTP Signature for XS2A, Isabel Connect, Ponto Connect

See more Ibanity Examples

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

For more information, see https://documentation.ibanity.com/http-signature

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
json: TChilkatJsonObject;
payload: WideString;
dtNow: TCkDateTime;
created: WideString;
crypt: TChilkatCrypt2;
sbDigestHdrValue: TChilkatStringBuilder;
request_target: WideString;
sbSigningString: TChilkatStringBuilder;
idempotencyKey: WideString;
signed_headers_list: WideString;
privKey: TPrivateKey;
rsa: TChilkatRsa;
sigBase64: WideString;
sbSigHeaderValue: TChilkatStringBuilder;

begin
// 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 := TChilkatJsonObject.Create(Self);
json.UpdateString('data.type','customerAccessToken');
json.UpdateString('data.attributes.applicationCustomerReference','15874569');

payload := json.Emit();
Memo1.Lines.Add('payload = ' + payload);

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

dtNow := TCkDateTime.Create(Self);
dtNow.SetFromCurrentSystemTime();
created := dtNow.GetAsUnixTimeStr(0);
Memo1.Lines.Add('created = ' + created);

// Step 2: Build the Digest header
crypt := TChilkatCrypt2.Create(Self);
crypt.HashAlgorithm := 'sha512';
crypt.EncodingMode := 'base64';
crypt.Charset := 'utf-8';

sbDigestHdrValue := TChilkatStringBuilder.Create(Self);
sbDigestHdrValue.Append('SHA-512=');
sbDigestHdrValue.Append(crypt.HashStringENC(json.Emit()));

Memo1.Lines.Add(sbDigestHdrValue.GetAsString());

// 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 := TChilkatStringBuilder.Create(Self);
sbSigningString.Append('(request-target): ');
sbSigningString.AppendLine(request_target,0);
sbSigningString.Append('host: ');
sbSigningString.AppendLine('api.ibanity.com',0);
sbSigningString.Append('digest: ');
sbSigningString.AppendLine(sbDigestHdrValue.GetAsString(),0);
sbSigningString.Append('(created): ');
sbSigningString.AppendLine(created,0);
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 := TPrivateKey.Create(Self);
success := privKey.LoadEncryptedPemFile('my_ibanity_signature_private_key.pem','pem_password');
if (success = 0) then
  begin
    Memo1.Lines.Add(privKey.LastErrorText);
    Exit;
  end;

rsa := TChilkatRsa.Create(Self);
rsa.PssSaltLen := 32;
rsa.EncodingMode := 'base64';
// Use the RSASSA-PSS signature algorithm
rsa.OaepPadding := 1;

success := rsa.ImportPrivateKeyObj(privKey.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(rsa.LastErrorText);
    Exit;
  end;

// Sign the signing string.
sigBase64 := rsa.SignStringENC(sbSigningString.GetAsString(),'sha-256');
if (rsa.LastMethodSuccess = 0) then
  begin
    Memo1.Lines.Add(rsa.LastErrorText);
    Exit;
  end;

// Build the signature header value.
sbSigHeaderValue := TChilkatStringBuilder.Create(Self);
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('"');

Memo1.Lines.Add(sbSigHeaderValue.GetAsString());
end;