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Dart

Get PDF DSS (Document Security Store)

See more PDF Signatures Examples

This example demonstrates how to extract the information from a PDF's DSS (Document Security Store), if a /DSS exists. (Just because a PDF is signed does not mean a /DSS will exists. In fact, the /DSS is typically created at the point of adding the 2nd or greater signature because the /DSS contains LTV (long term validation) information about the previous signature at the time of adding an additional signature.)

Note: This example requires Chilkat v9.5.0.85 or greater.

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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 pdf = CkPdf();

  try {
    pdf.loadFile('qa_data/pdf/sign_testing_1/helloSigned2.pdf');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final json = CkJsonObject();
  json.emitCompact = false;

  pdf.getDss(json);
  print(json.emit());

  // The document security store contains certificates, OCSP responses, and CRLs.
  // The following JSON is a sample of what the /DSS can contain.
  // Unfortunately, our sample contains /Certs and /OCSPs, but no /CRLs.
  // It's no problem because whatever JSON you get back, you can use the
  // following online tool to generate code to parse.
  // Generate Parsing Code from JSON

  // The code generated by the online tool for this JSON is shown below..

  // {
  //   "/VRI": {
  //     "/EC5BB34CC1F8A0C5FE674427E16E313A08C80808": {}
  //   },
  //   "/Certs": [
  //     {
  //       "serial": "02",
  //       "validFrom": "2011-08-07T19:00:00-05:00",
  //       "validTo": "2021-08-10T23:59:59-05:00",
  //       "expired": false,
  //       "subject": {
  //         "CN": "XYZ Corporation",
  //         "O": "XYZ"
  //       },
  //       "issuer": {
  //         "CN": "XYZ Corporation",
  //         "O": "XYZ"
  //       },
  //       "keyType": "RSA",
  //       "keySize": "2048",
  //       "der": "MIIDz...Q4Zt"
  //     },
  //     {
  //       "serial": "01",
  //       "validFrom": "2011-08-07T19:00:00-05:00",
  //       "validTo": "2021-08-10T23:59:59-05:00",
  //       "expired": false,
  //       "subject": {
  //         "CN": "XYZ Corporation",
  //         "O": "XYZ"
  //       },
  //       "issuer": {
  //         "CN": "XYZ Corporation",
  //         "O": "XYZ"
  //       },
  //       "keyType": "RSA",
  //       "keySize": "2048",
  //       "der": "MIID...jXYFc="
  //     },
  //     {
  //       "serial": "0AA125D6D6321B7E41E405DA3697C215",
  //       "validFrom": "2016-01-07T06:00:00-06:00",
  //       "validTo": "2031-01-07T12:00:00-06:00",
  //       "expired": false,
  //       "subject": {
  //         "CN": "DigiCert SHA2 Assured ID Timestamping CA",
  //         "OU": "www.digicert.com",
  //         "O": "DigiCert Inc",
  //         "C": "US"
  //       },
  //       "issuer": {
  //         "CN": "DigiCert Assured ID Root CA",
  //         "OU": "www.digicert.com",
  //         "O": "DigiCert Inc",
  //         "C": "US"
  //       },
  //       "keyType": "RSA",
  //       "keySize": "2048",
  //       "der": "MIIF...OUg=="
  //     },
  //     {
  //       "serial": "04CD3F8568AE76C61BB0FE7160CCA76D",
  //       "validFrom": "2019-09-30T19:00:00-05:00",
  //       "validTo": "2030-10-17T00:00:00-05:00",
  //       "expired": false,
  //       "subject": {
  //         "CN": "TIMESTAMP-SHA256-2019-10-15",
  //         "O": "DigiCert, Inc.",
  //         "C": "US"
  //       },
  //       "issuer": {
  //         "CN": "DigiCert SHA2 Assured ID Timestamping CA",
  //         "OU": "www.digicert.com",
  //         "O": "DigiCert Inc",
  //         "C": "US"
  //       },
  //       "keyType": "RSA",
  //       "keySize": "2048",
  //       "der": "MIIG...MJtPc="
  //     },
  //     {
  //       "serial": "0CE7E0E517D846FE8FE560FC1BF03039",
  //       "validFrom": "2006-11-09T18:00:00-06:00",
  //       "validTo": "2031-11-10T00:00:00-06:00",
  //       "expired": false,
  //       "subject": {
  //         "CN": "DigiCert Assured ID Root CA",
  //         "OU": "www.digicert.com",
  //         "O": "DigiCert Inc",
  //         "C": "US"
  //       },
  //       "issuer": {
  //         "CN": "DigiCert Assured ID Root CA",
  //         "OU": "www.digicert.com",
  //         "O": "DigiCert Inc",
  //         "C": "US"
  //       },
  //       "keyType": "RSA",
  //       "keySize": "2048",
  //       "der": "MIIDt...FL6Lw8g=="
  //     },
  //     {
  //       "serial": "E4D34D01798BE686424AF7F6F0C3BF41",
  //       "validFrom": "2015-03-24T10:58:16-05:00",
  //       "validTo": "2039-12-31T23:59:59-06:00",
  //       "expired": false,
  //       "subject": {
  //         "CN": "www.xyz.com"
  //       },
  //       "issuer": {
  //         "CN": "www.xyz.com"
  //       },
  //       "keyType": "RSA",
  //       "keySize": "1024",
  //       "der": "MIIB9DCCAWG...UR10lz"
  //     }
  //   ],
  //   "/OCSPs": [
  //     {
  //       "responseStatus": 0,
  //       "responseTypeOid": "1.3.6.1.5.5.7.48.1.1",
  //       "responseTypeName": "ocspBasic",
  //       "response": {
  //         "responderIdChoice": "KeyHash",
  //         "responderKeyHash": "Reuir/SSy4IxLVGLp6chnfNtyA8=",
  //         "dateTime": "20201005173921Z",
  //         "cert": [
  //           {
  //             "hashOid": "1.3.14.3.2.26",
  //             "hashAlg": "SHA-1",
  //             "issuerNameHash": "98S+C0C1w0QzPT+uuU1uONr67FE=",
  //             "issuerKeyHash": "Reuir/SSy4IxLVGLp6chnfNtyA8=",
  //             "serialNumber": "0AA125D6D6321B7E41E405DA3697C215",
  //             "status": 0,
  //             "thisUpdate": "20201005173921Z",
  //             "nextUpdate": "20201012173921Z"
  //           }
  //         ]
  //       }
  //     },
  //     {
  //       "responseStatus": 0,
  //       "responseTypeOid": "1.3.6.1.5.5.7.48.1.1",
  //       "responseTypeName": "ocspBasic",
  //       "response": {
  //         "responderIdChoice": "KeyHash",
  //         "responderKeyHash": "9LbhIB3+Ka7S5GGlsqIlssgXNW4=",
  //         "dateTime": "20201006114501Z",
  //         "cert": [
  //           {
  //             "hashOid": "1.3.14.3.2.26",
  //             "hashAlg": "SHA-1",
  //             "issuerNameHash": "+YYA+KSr7NIxRSxCjUNQo25SyD0=",
  //             "issuerKeyHash": "9LbhIB3+Ka7S5GGlsqIlssgXNW4=",
  //             "serialNumber": "04CD3F8568AE76C61BB0FE7160CCA76D",
  //             "status": 0,
  //             "thisUpdate": "20201006114501Z",
  //             "nextUpdate": "20201013110001Z"
  //           }
  //         ]
  //       }
  //     }
  //   ]
  // }

  final responseDateTime = CkDtObj();
  final thisUpdate = CkDtObj();
  final nextUpdate = CkDtObj();
  var serial = '';
  var validFrom = '';
  var validTo = '';
  var subjectCN = '';
  var subjectO = '';
  var issuerCN = '';
  var issuerO = '';
  var keyType = '';
  var keySize = '';
  var der = '';
  var subjectOU = '';
  var subjectC = '';
  var issuerOU = '';
  var issuerC = '';
  var responseStatus = 0;
  var responseTypeOid = '';
  var responseTypeName = '';
  var responseResponderIdChoice = '';
  var responseResponderKeyHash = '';
  var j = 0;
  var countJ = 0;
  var hashOid = '';
  var hashAlg = '';
  var issuerNameHash = '';
  var issuerKeyHash = '';
  var serialNumber = '';
  var status = 0;

  var i = 0;
  var countI = json.sizeOfArray('/Certs');
  while (i < countI) {
    json.i = i;
    serial = json.stringOf('/Certs[i].serial');
    validFrom = json.stringOf('/Certs[i].validFrom');
    validTo = json.stringOf('/Certs[i].validTo');
    json.boolOf('/Certs[i].expired');
    subjectCN = json.stringOf('/Certs[i].subject.CN');
    subjectO = json.stringOf('/Certs[i].subject.O');
    issuerCN = json.stringOf('/Certs[i].issuer.CN');
    issuerO = json.stringOf('/Certs[i].issuer.O');
    keyType = json.stringOf('/Certs[i].keyType');
    keySize = json.stringOf('/Certs[i].keySize');
    der = json.stringOf('/Certs[i].der');
    subjectOU = json.stringOf('/Certs[i].subject.OU');
    subjectC = json.stringOf('/Certs[i].subject.C');
    issuerOU = json.stringOf('/Certs[i].issuer.OU');
    issuerC = json.stringOf('/Certs[i].issuer.C');
    i++;
  }

  i = 0;
  countI = json.sizeOfArray('/OCSPs');
  while (i < countI) {
    json.i = i;
    responseStatus = json.intOf('/OCSPs[i].responseStatus');
    responseTypeOid = json.stringOf('/OCSPs[i].responseTypeOid');
    responseTypeName = json.stringOf('/OCSPs[i].responseTypeName');
    responseResponderIdChoice = json.stringOf('/OCSPs[i].response.responderIdChoice');
    responseResponderKeyHash = json.stringOf('/OCSPs[i].response.responderKeyHash');
    json.dtOf('/OCSPs[i].response.dateTime', false, responseDateTime);
    j = 0;
    countJ = json.sizeOfArray('/OCSPs[i].response.cert');
    while (j < countJ) {
      json.j = j;
      hashOid = json.stringOf('/OCSPs[i].response.cert[j].hashOid');
      hashAlg = json.stringOf('/OCSPs[i].response.cert[j].hashAlg');
      issuerNameHash = json.stringOf('/OCSPs[i].response.cert[j].issuerNameHash');
      issuerKeyHash = json.stringOf('/OCSPs[i].response.cert[j].issuerKeyHash');
      serialNumber = json.stringOf('/OCSPs[i].response.cert[j].serialNumber');
      status = json.intOf('/OCSPs[i].response.cert[j].status');
      json.dtOf('/OCSPs[i].response.cert[j].thisUpdate', false, thisUpdate);
      json.dtOf('/OCSPs[i].response.cert[j].nextUpdate', false, nextUpdate);
      j++;
    }

    i++;
  }
}