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Dart

Sign and Encrypt using Cert to produce -----BEGIN PKCS7----- ... -----END PKCS7-----

See more Encryption Examples

Demonstrates how to first sign content using your own cert + private key to produce PKCS7 binary output. Then encrypt the signed binary output using the recipient's public key to produce output such as:
-----BEGIN PKCS7-----
MIIHPwYJKoZIhvcNAQcEoIIHMDCCBywC ...
...
...
-----END PKCS7-----

Chilkat Dart Downloads

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 crypt = CkCrypt2();

  final toBeSignedAndEncrypted = 'This string is to be signed and then encrypted.';

  final myCert = CkCert();
  try {
    myCert.loadPfxFile('qa_data/pfx/cert_test123.pfx', 'test123');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  try {
    crypt.setSigningCert(myCert);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Get the PKCS7 output in base64 format.
  crypt.encodingMode = 'base64';
  // Perhaps we don't want the entire cert chain to be included in the signature?
  crypt.includeCertChain = false;
  final signedPkcs7 = crypt.opaqueSignStringENC(toBeSignedAndEncrypted);

  // We're going to encrypt the binary PKCS7 signature (which contains the content)
  final bdPkcs7 = CkBinData();
  bdPkcs7.appendEncoded(signedPkcs7, 'base64');

  // ---------------------------------------------------
  // Now for the encryption...

  // Specify the encryption to be used.
  // "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped) message.
  crypt.cryptAlgorithm = 'pki';
  crypt.pkcs7CryptAlg = 'aes';
  crypt.keyLength = 128;
  crypt.oaepHash = 'sha256';
  crypt.oaepPadding = true;

  // A certificate is needed as the encryption key..
  final cert = CkCert();
  try {
    cert.loadFromFile('qa_data/certs/testCert.pem');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Tell the crypt object to use the certificate.
  crypt.setEncryptCert(cert);

  try {
    crypt.encryptBd(bdPkcs7);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
  final sb = CkStringBuilder();
  sb.appendLine('-----BEGIN PKCS7-----', true);
  sb.append(bdPkcs7.getEncoded('base64_mime'));
  sb.appendLine('-----END PKCS7-----', true);

  final outStr = sb.getAsString();

  print(outStr);

  // Sample output:

  // -----BEGIN PKCS7-----
  // MIIMFQYJKoZIhvcNAQcDoIIMBjCCDAICAQAxggH5MIIB9QIBADCBsTCBmzELMAkGA1UEBhMCR0Ix
  // GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR
  // Q09NT0RPIENBIExpbWl0ZWQxQTA/BgNVBAMTOENPTU9ETyBTSEEtMjU2IENsaWVudCBBdXRoZW50
  // aWNhdGlvbiBhbmQgU2VjdXJlIEVtYWlsIENBAhEAuBl4qE2MODB05C5h53M5UDA4BgkqhkiG9w0B
  // AQcwK6APMA0GCWCGSAFlAwQCAQUAoRgwFgYJKoZIhvcNAQEIMAkGBSsOAwIaBQAEggEAA34hkvxY
  // TXMUAsWBmnRIvfFK920WeUVenM4ob7qibDiaXI2qWBgzkIfQH2T1vIYHHzNQuaaiTrK3THn8Nzfy
  // RFqTnhfWwsIL/yinHVn5rA9CbHFmxqHr2UctZxLB7x/DxV7pjqpTTveCwgC9FykxGBcNO92Thlho
  // bHyq1VM+tm4ppkyV982xL1VAIUX6BvqRlfPsB3hJsdGz/Z3HBdLNgkp2z8mMcLZx9vXwZ3Nyrsi1
  // JqUP4wJ+HHYb5aJseE2UtrEh+s/eq+49OS9BhAWKRlmTxZo8XSQPNeVIRt0HvFAr/+E+jiyASI7b
  // 9mjPPWP36ia4+/yhUwchnD/bJxa5gjCCCf4GCSqGSIb3DQEHATAdBglghkgBZQMEAQIEEFApbYsk
  // 2qdwHv7dkngFg3CAggnQiMpHuoyOxSilO2lowI73vwX44PKKu1aGFW+mCbne/UZfOAgbvpHQ1LcP
  // Nam+I8MZRtT7nqN3ZWIIvW468z2Z8ne4DqO/D0adlSwE66Z2JxkZncrUM+QR1Oo9sz7aY0eUxzeB
  // 5yTUcm3gZSFsKJ0czKzxF7r8IE2ytRVjYWbSZ4eGcJ9Pjpxk38+IZTkcWyzreOCSE9NvH+mefJHT
  // IeTH05w96Rei5YEq1Zn41+bw/Yh19hKHarudAerA1v5f36gz/eWMF2VF5/D23dW3tbw1DpDc/96B
  // 3Mu4/Z1CREQ1C6NLlRHIoULADScuzyQTlmbj2v7vBJa46GZvjswyDbALIJ7B026JHpSUCPcf90q4
  // qlAoOjLCOSEMb8qhHHchwEaHcydCRB1bschj+eBHJp6R3spbQXCtRnSLuvTdBSPVR5sD140q8f68
  // YHyozbBWkxp5vv6fOyQMBibUhW7tyLod7M4pcgZlSKE6v9qhOCnE5Ym+wkX/t78E+W1wflmAwVJo
  // WZXoJNul6b6Ith9nCWwX3d6iJY/mdapaqabFGV2qFu1MG1wiKzrZtl/5qbVNXeraLLOTBW+hPeNt
  // hb0XpWHtR28Ig1Y51P2wEGNoTsZrkJrOn8Go0mgHlWnUPLJImyDZYdJF6ZvlRhpSj/99RLHZORT7
  // m1akNtXeQhfE3bj2tlYkviuBYtetwIGos9y74XCQWkours/5as6WqKozYHpFigPB3OLdWbq2txxc
  // k741BL/Mw5ugtHmPqNzRn4txMvB+lAcE1y75sESqC774bSCmrn+uVmOTZFvNob0dhZNTGsbcLCTe
  // LLGS3ZUscah/9iVte5xGnsCOSq18PjPIdqMvzSEcrYQVyqe2/68mae6dpk7gyeiTYpDsSYO+KaHw
  // bwwViPnVOhRkXxU54unymiSmgIRrhn+hsbkxvJk3Q307a7wcj+/ygw5stTV2hLmIQotMvmlpFTLZ
  // PhB5eyFIZaWKV8XJgPV5JInrm39taw8ClHeSC31BNgfkX5u2h0pA1f5zMZ/SvgriW0Xumyoy/9XC
  // eVL6fCZEWmaRZbAy5RlVELR/N2/Z5VS6s8U6Wrck9Zq9sGelf+0QWbCEwNoxQf+xxH55QnzHRvpu
  // s839qRy/5msXSYno0fl3uE6cP/bWwk0Rvt3QYp75UTZDkfXl0ywy00V6AMPssKlDZe0GYWaqcHqz
  // xj2sOK++Iz0tlmhS6QWcGrgWyVaHG9E2van/yLE4Sl4qnKt88/vK+cTKCrRCStslrt2Z/1myLnaB
  // 6b6uAlVFk+kIHH82WaXxfCVedoGVk+jL3qPRbQiCzm7O66N6ecXIFWQ10sR5AXk/k4M6rM2Zhgoh
  // yjPAxEHOzZ7nTLMb2MvPSV4KbrQT7Qs8prefY6o1OANXu4HRzL+zzttiIrV72vVemF80q7e5wYKR
  // pGC85zZwz084RSWSwHTXDeWpI8zRPM7eboR97q9dfy7V23YlYJyM2RYrusweULib6X4me9nPhOzD
  // 4KmqI6FSOvwTUdEDb8k32+GVB+zXsEhI6uPFz+Fgve8WUKcWX0DFoD905+KICeDFlOxWjB5FhKqF
  // DysgV1FCCN8fGWRvbe7R74KR8SYwUOSAE63PDtGDWK345sOQXp5b0Vv4lVG5/ECZqYCM9RixLsyx
  // vrozd8L0wqQJ5vlMOt9wksSYa8zzShC/tO3aGyw9NLz6y3lKoz3NfA04k8IyT2wtx2cG82h4bdwo
  // aBPdFlV9P/WlVPJXgRv0GFJFX4HiVMQBEn3Rj8H/BHzZYPo9tLnPRmuoTWv+HaoAEzxwQ4O+L9av
  // 0BO0eJSJNxs3UTaxl/psm17EinNLCV7lx7jKppj8v7Xxdem0+Fu0ME92XmFKG52tT9XkniF6orNP
  // 9G48f93G7tIx4CLNT5QXhnUejZG0v0uBxnL5dURV4W/49Qg49lEZZr6yUZlDUhMBSKwCW/gcTeGv
  // XVscW4UaGH9ewPFYVHNaDh7ehxkaTtuTrVpS7fPhaWLwozR1ro+U/WIqjE7QeharK+eqJN7OJNcV
  // vx42zsCCzAankT70bGsEqtA/il4IbxEa3EQTqOMLdxSJ/62IZRKGNxwZnRou8i1pswMM5q/9/ITi
  // MweZHH+AWeXrf5CLVObq2ZPk6NUPScFKSy7Vao1SxORhj+YJDd3vznWpjjq88Qs1ntwitY13jnxh
  // 58XEwI+vkjAY34lOEtr2UGXS0DrANN0//VMk40WZat5rVnx9XITC9RmGFvtM0RDgMZ3BOEXyI1mI
  // nGLILcAVW+mnxJcafwFCbI1nd6KyfQU+/RmXdOLPtKMjEKm2jBZt3UGaxLkHKCuzESdYtlUkbbcL
  // K5ynNEANfBNJjf494Sd+jbKe9031E7bl4nbQGFpmJDEnszWfKMdg9ChlOfYLM26pFN0hQahA26fn
  // PgrBYvKaHauR0SUPtibwmy2kIdKoakJoIvyDDYh6HHrdcwGVHfA5nCSFIHGsv3lcdLc2sMq38TR/
  // zh7verXj0Aa71VFfmxBrRvasvdp9ms7GZFzDzMq2yf+a4knzTdRHtst6jOoTXb0RXJuLfvDTJqmF
  // tue95J8OELZOpWnp21Yj52So78BlcOC4W3VexT4hyHhtziG9BKeXvc6WSU1pUEoNkXAXXrHLi/AG
  // lC45zJ+LzDp/3rOzGQ5SIIi67ZSSQNiW85ektAoSEJZlZ1xaXt9DEbugpkySfjI/GFxSmFZqCs6h
  // RNT4f8BAKX56ItobBORZbvk12Mn5QrxIEGFbOFcLt6cA/zqixS8ej1cz+SsMUkuzl/KDh6ncXeuF
  // 2DawyL7/konWins6Jo3gYhRgw4fpck14aaEF5/+h3FvgVw23FieWYc6AImn/2zvtv6+gCJl7YnrG
  // 9zSjHx2Kf7WRiFbpSqYXGGA0iD0b7So9oyrTItepIRQh0OFcDhCGXvhl2Sb7IQM7sL3WvbAHcseS
  // 0xJiEIZogWbVKL5OqAn/VrJsL+0atvkh6qy5FVmk9CBWh92lkmwWyk8+CoTVC6DPMRXLv/MQar2W
  // j0cOL12vohVJe9MSHTMR6kHaaxj1J8b5AswZTBsbgFo16Q6ihxLC1fd70OM1c6Hak341UgCxHsOr
  // j9JfT+r5jpK3booIzBorGNJOkAuaBAEKdcnNpyCP2sDCzG+7Ws1H+lJzXVDXARftZSbMvfLctU49
  // 5YZl+bBifBF8fSSSRNKXMbPeyww1idjezWKiXQC3hA6VPKtW7rn1py7hTlkdm6os1jW9vmSmz30j
  // KHvey6Kcy+fdc1gyYmXhSDD55uYVrj1JmbaZvIeGTh8cQ8E4Dsq2Hy2PQ8S2e2S6YcJ9X6yNkwXG
  // KrqG2vK4AeBuro1IfoUG1EJ17Q==
  // -----END PKCS7-----
}