Dart

Create PKCS7 Attached/Opaque Signature (S/MIME)

See more MIME Examples

Create an S/MIME message with a PKCS7 attached/opaque signature. Dart

import 'package:chilkat/chilkat.dart';

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

  final mime = CkMime();

  // Load a certificate w/ private key for signing.
  // There are many ways of getting a certificate object:
  // from a pfx file, from .cer and private-key files, from the
  // Windows registry-based certificate stores, etc.
  // Load a PFX file into a certificate object.
  final cert = CkCert();
  final pfxFilepath = 'pfxFiles/something.pfx';
  final pfxPassword = 'secret';
  try {
    cert.loadPfxFile(pfxFilepath, pfxPassword);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Create a very simple MIME message to be signed:
  mime.addHeaderField('Subject', 'This is a test');
  mime.addHeaderField('MyCustomHeader', 'abc123');
  mime.contentType = 'text/plain';
  mime.setBody('This is a plain-text body.');

  // Examine the MIME prior to signing:
  print('--- MIME prior to signing ---');
  print(mime.getMime());

  // The MIME prior to signing looks like this:
  // -------------------------------------------------------------------------------

  // Subject: This is a test
  // MyCustomHeader: abc123
  // Content-Type: text/plain
  // 
  // This is a plain-text body.

  // -------------------------------------------------------------------------------

  // The default hash algorithm used in the signing process is "SHA1".
  // To change it, set the SigningHashAlg property:
  mime.signingHashAlg = 'SHA256';

  // Convert the MIME to PKCS7 signed-data.
  try {
    mime.convertToSigned(cert);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Examine the signed MIME
  print('--- MIME converted to PKCS7 signed-data ---');
  print(mime.getMime());

  // The MIME after signing looks like this:
  // -------------------------------------------------------------------------------

  // Subject: This is a test
  // MyCustomHeader: abc123
  // Content-Disposition: attachment; filename="smime.p7m";
  // Content-Transfer-Encoding: base64
  // Content-Type: application/x-pkcs7-mime;
  //  name="smime.p7m"; smime-type="signed-data";
  // 
  // MIIObAYJKoZIhvcNAQcCoIIOXTCCDlkCAQExDzANBglghkgBZQMEAgEFADB2BgkqhkiG9w0BBwGg
  // aQRnU3ViamVjdDogVGhpcyBpcyBhIHRlc3QNCk15Q3VzdG9tSGVhZGVyOiBhYmMxMjMNCkNvbnRl
  // bnQtVHlwZTogdGV4dC9wbGFpbg0KDQpUaGlzIGlzIGEgcGxhaW4tdGV4dCBib2R5LqCCCaAwggRm
  // MIIDTqADAgECAhBEvgyLUAAktBHTNi3gs18bMA0GCSqGSIb3DQEBBQUAMIGVMQswCQYDVQQGEwJV
  // UzELMAkGA1UECBMCVVQxFzAVBgNVBAcTDlNhbHQgTGFrZSBDaXR5MR4wHAYDVQQKExVUaGUgVVNF
  // UlRSVVNUIE5ldHdvcmsxITAfBgNVBAsTGGh0dHA6Ly93d3cudXNlcnRydXN0LmNvbTEdMBsGA1UE
  // AxMUVVROLVVTRVJGaXJzdC1PYmplY3QwHhcNOTkwNzA5MTgzMTIwWhcNMTkwNzA5MTg0MDM2WjCB
  // lTELMAkGA1UEBhMCVVMxCzAJBgNVBAgTAlVUMRcwFQYDVQQHEw5TYWx0IExha2UgQ2l0eTEeMBwG
  // A1UEChMVVGhlIFVTRVJUUlVTVCBOZXR3b3JrMSEwHwYDVQQLExhodHRwOi8vd3d3LnVzZXJ0cnVz
  // dC5jb20xHTAbBgNVBAMTFFVUTi1VU0VSRmlyc3QtT2JqZWN0MIIBIjANBgkqhkiG9w0BAQEFAAOC
  // AQ8AMIIBCgKCAQEAzqqBP6OjYXiqMQBVlRGeJw8fHN86m4JoMMBKYR3xLw76vnn3pSPvVVGWhM3b
  // 47luPjHYCiBnx/TZv5TrRwQ+As4qol2HBAn2MJ0Yipeyqhz8QdKhNsv7PZG659lwNfrk55DDm6Ob
  // 0zz1Epl3sbcJ4GjmHLjzlGOIamr+C3bJvvQi5Ge5qxped8GFB90NbL/uBsd3akGepw/X++6UF7f8
  // hb6kq8QcMd3XttHk8O/fFo+yUpPXodSJoQcuv+EBEkIeGuHYlTTbZHko/7ouEcLl6FuSSPtHC8Js
  // 2q0yg0HzpeVBcP1lkG36+lHE+b2WKxkELNNtp9zwf2+DZeJqq4eGdQIDAQABo4GvMIGsMAsGA1Ud
  // DwQEAwIBxjAPBgNVHRMBAf8EBTADAQH/MB0GA1UdDgQWBBTa7WR0FJwUPKvdmam9WyhNizzJ2DBC
  // BgNVHR8EOzA5MDegNaAzhjFodHRwOi8vY3JsLnVzZXJ0cnVzdC5jb20vVVROLVVTRVJGaXJzdC1P
  // YmplY3QuY3JsMCkGA1UdJQQiMCAGCCsGAQUFBwMDBggrBgEFBQcDCAYKKwYBBAGCNwoDBDANBgkq
  // hkiG9w0BAQUFAAOCAQEACB9SsTdEeNv9zrnalZaYqlVkgLVaQN0hpcXB818sTMhHWmnq6PA1NfTQ
  // JfPIpqSHSr0bsXMIvdTDyrY1u1mGdzHNp4AUrhPv/LFI+WslJS1RtixtRcGYyIpWXT7uQ04+ayeO
  // 0DpLhQtf0+1qp3XL0VqHLzl1E1pysAKBn77wD4RUIGJsadThTcYNmUMBDRKWjHidv1CisUSqas8X
  // es9vD9T4JFVf8DQWSWY+UEbJY3E4MWK4YrnzU61stSuiEqoZTwnaXueTxo4UCP7wMIAYoIaFTch9
  // 14sD/m7V950WrJIsoCPlnJFSH5TfF5Rzw7PBwXEFIAB4vRNSHag+zQAfyDCCBTIwggQaoAMCAQIC
  // EQDm/GiUo2tiCnVnsAEgJ0r7MA0GCSqGSIb3DQEBBQUAMIGVMQswCQYDVQQGEwJVUzELMAkGA1UE
  // CBMCVVQxFzAVBgNVBAcTDlNhbHQgTGFrZSBDaXR5MR4wHAYDVQQKExVUaGUgVVNFUlRSVVNUIE5l
  // dHdvcmsxITAfBgNVBAsTGGh0dHA6Ly93d3cudXNlcnRydXN0LmNvbTEdMBsGA1UEAxMUVVROLVVT
  // RVJGaXJzdC1PYmplY3QwHhcNMDkxMDEyMDAwMDAwWhcNMTAxMDEyMjM1OTU5WjCBoDELMAkGA1UE
  // BhMCVVMxDjAMBgNVBBEMBTYwMTg3MREwDwYDVQQIDAhJbGxpbm9pczEQMA4GA1UEBwwHV2hlYXRv
  // bjEaMBgGA1UECQwRMTcxOSBFIEZvcmVzdCBBdmUxHzAdBgNVBAoMFkNoaWxrYXQgU29mdHdhcmUs
  // IEluYy4xHzAdBgNVBAMMFkNoaWxrYXQgU29mdHdhcmUsIEluYy4wggEiMA0GCSqGSIb3DQEBAQUA
  // A4IBDwAwggEKAoIBAQC5ueUJPjI74J5Yavc3JUCWHEMMd2C9T+4VDuUcN7vzYuIOjsyV1yhzAl8+
  // uxzE+dhfcRK8qw9JbRV56Dzfyz5DqJH9x0rlbzkM24NeNZyM1kXIs2NHCJTYlYUqlVLZ2SXpiqru
  // nnYEFScZho3knWoBYC4841sdUay70pqluo2Y1CBbx5t+zYPXit370hEGzKLNK6XRTevcVQQMvL/f
  // d/gz241M8KBT8yvqTAjv6NJz9tHNUqhYO5mTT65nsIwKQ5/T8L+hsOHi4VM2QdVW6ZD9jrfPIfES
  // yOyfXCx2l9oEHfB3gwgdYQ4Mq9hRG77mIc9H+pw1V0yMmQmEVs0LP6hvAgMBAAGjggFuMIIBajAf
  // BgNVHSMEGDAWgBTa7WR0FJwUPKvdmam9WyhNizzJ2DAdBgNVHQ4EFgQUBMe/RfjpWAOjAMHml1qw
  // DvPa4OowDgYDVR0PAQH/BAQDAgeAMAwGA1UdEwEB/wQCMAAwEwYDVR0lBAwwCgYIKwYBBQUHAwMw
  // EQYJYIZIAYb4QgEBBAQDAgQQMEYGA1UdIAQ/MD0wOwYMKwYBBAGyMQECAQMCMCswKQYIKwYBBQUH
  // AgEWHWh0dHBzOi8vc2VjdXJlLmNvbW9kby5uZXQvQ1BTMEIGA1UdHwQ7MDkwN6A1oDOGMWh0dHA6
  // Ly9jcmwudXNlcnRydXN0LmNvbS9VVE4tVVNFUkZpcnN0LU9iamVjdC5jcmwwNAYIKwYBBQUHAQEE
  // KDAmMCQGCCsGAQUFBzABhhhodHRwOi8vb2NzcC5jb21vZG9jYS5jb20wIAYDVR0RBBkwF4EVYWRt
  // aW5AY2hpbGthdHNvZnQuY29tMA0GCSqGSIb3DQEBBQUAA4IBAQAP/2IpG75SHSFFqjHqvCXy0n0O
  // MTQk2IexnIUBlF7wm0oZquXBG2GlOPd9IXNr7k3wf4G+nZ6rgit6slVT1VxZS8RzqhGT3ZRTa2ud
  // dSqJyKxxrqdBJMY/WWaWVtCSU74AKAAm/ONwD1Zz39IZ2Mr8ApXn2LnZy4ZgI3hZnVR8I92/sppl
  // +NKWr0iMBpcz2KEwXZ5lrS5/4qRFlY+LQgRBFnjoM9WDW1lGEqeHFQQ/dqyrNiRAp+l7OzPBS4aM
  // nfxS+Yj/blpnuW41dVi9TJTXozRwiHzQ41FfrkJMD4JZULc539SK1EU1cYMl13x3JODHlng2IrjZ
  // pCKrFCsSCP2BMYIEJTCCBCECAQEwgaswgZUxCzAJBgNVBAYTAlVTMQswCQYDVQQIEwJVVDEXMBUG
  // A1UEBxMOU2FsdCBMYWtlIENpdHkxHjAcBgNVBAoTFVRoZSBVU0VSVFJVU1QgTmV0d29yazEhMB8G
  // A1UECxMYaHR0cDovL3d3dy51c2VydHJ1c3QuY29tMR0wGwYDVQQDExRVVE4tVVNFUkZpcnN0LU9i
  // amVjdAIRAOb8aJSja2IKdWewASAnSvswDQYJYIZIAWUDBAIBBQCgggJKMBgGCSqGSIb3DQEJAzEL
  // BgkqhkiG9w0BBwEwHAYJKoZIhvcNAQkFMQ8XDTEwMDYzMDE0NTg0MFowLwYJKoZIhvcNAQkEMSIE
  // ILEFXqrFbp/l0XOJyyjW1IJhjJxJaOhLUlZTc8VcabVMMF8GCSqGSIb3DQEJDzFSMFAwCwYJYIZI
  // AWUDBAECMAoGCCqGSIb3DQMHMA4GCCqGSIb3DQMCAgIAgDANBggqhkiG9w0DAgIBQDAHBgUrDgMC
  // BzANBggqhkiG9w0DAgIBKDCBvAYJKwYBBAGCNxAEMYGuMIGrMIGVMQswCQYDVQQGEwJVUzELMAkG
  // A1UECBMCVVQxFzAVBgNVBAcTDlNhbHQgTGFrZSBDaXR5MR4wHAYDVQQKExVUaGUgVVNFUlRSVVNU
  // IE5ldHdvcmsxITAfBgNVBAsTGGh0dHA6Ly93d3cudXNlcnRydXN0LmNvbTEdMBsGA1UEAxMUVVRO
  // LVVTRVJGaXJzdC1PYmplY3QCEQDm/GiUo2tiCnVnsAEgJ0r7MIG+BgsqhkiG9w0BCRACCzGBrqCB
  // qzCBlTELMAkGA1UEBhMCVVMxCzAJBgNVBAgTAlVUMRcwFQYDVQQHEw5TYWx0IExha2UgQ2l0eTEe
  // MBwGA1UEChMVVGhlIFVTRVJUUlVTVCBOZXR3b3JrMSEwHwYDVQQLExhodHRwOi8vd3d3LnVzZXJ0
  // cnVzdC5jb20xHTAbBgNVBAMTFFVUTi1VU0VSRmlyc3QtT2JqZWN0AhEA5vxolKNrYgp1Z7ABICdK
  // +zANBgkqhkiG9w0BAQEFAASCAQBfYh75saVFNXRPOzXOemaoVIFz+OHSsQB1fqXbV+hjGkxuvWAT
  // ldq32luVFFCz2gErWDT8eZ0yFVVwi16XyP7ptZeGU4cIGtrOozq78dziWwbNB021c3Dcw0vmH83m
  // FrU8ZNXYhL2+Lu4PlgvSCxHtC9EKrsP0s3WvBk3nMgXhu4Nmvkl1pCAofhAXWs545TfFB3jLEgeR
  // spbT6PhRR2lErXKF/Ga5NUyUqpw/Ba2YB3fFsbwiMyncmYicnUT2eYxxYBPtX9X6DQSKh3+iLNz0
  // sx89fluXIoqWONjR/XyN8zYd6WtEqMMwY6HQPAblFEuMPHZIhC0h/hfGAVisKLmh
  // 

  // -------------------------------------------------------------------------------
}