Set a Per-Recipient JWE Header

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.SetRecipientHeader, which sets the per-recipient unprotected header for a recipient index.

var
success: Integer;
jwe: TChilkatJwe;
header: TChilkatJsonObject;
base64Key: WideString;
recipHeader: TChilkatJsonObject;
sbContent: TChilkatStringBuilder;
sbJwe: TChilkatStringBuilder;

begin
success := 0;

jwe := TChilkatJwe.Create(Self);

//  Protected header: AES key-wrap with AES-256-GCM content encryption.
header := TChilkatJsonObject.Create(Self);
header.UpdateString('alg','A256KW');
header.UpdateString('enc','A256GCM');
success := jwe.SetProtectedHeader(header.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(jwe.LastErrorText);
    Exit;
  end;

//  The 256-bit key-wrapping key (base64) for recipient index 0.  In production, obtain the key from a
//  secure source rather than hard-coding it.
base64Key := 'YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=';
success := jwe.SetWrappingKey(0,base64Key,'base64');
if (success = 0) then
  begin
    Memo1.Lines.Add(jwe.LastErrorText);
    Exit;
  end;

//  Set the per-recipient unprotected header for recipient 0, for example a key id used to identify
//  which key a recipient should use.
recipHeader := TChilkatJsonObject.Create(Self);
recipHeader.UpdateString('kid','recipient-key-1');
success := jwe.SetRecipientHeader(0,recipHeader.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(jwe.LastErrorText);
    Exit;
  end;

sbContent := TChilkatStringBuilder.Create(Self);
sbContent.Append('This is the secret content.');
sbJwe := TChilkatStringBuilder.Create(Self);
success := jwe.EncryptSb(sbContent.ControlInterface,'utf-8',sbJwe.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(jwe.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add(sbJwe.GetAsString());