(Android™) Verify a CAdES-BES Signature and Examine Signature Contents

Demonstrates how to validate a .p7m (.p7s) signature and examine the contents of the signature.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

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

    CkCrypt2 crypt = new CkCrypt2();

    String outputFile = "qa_output/original.xml";
    String inFile = "qa_data/p7m/fattura_signature.xml.p7m";

    // Verify the signature and extract the contained file, which in this case is XML.
    boolean success = crypt.VerifyP7M(inFile,outputFile);
    if (success == false) {
        Log.i(TAG, crypt.lastErrorText());
        return;
        }

    Log.i(TAG, "Signature validated.");

    // Now let's examine the information about the signature.
    CkJsonObject json = crypt.LastJsonData();
    if (crypt.get_LastMethodSuccess() == false) {
        // This should never be the case...
        Log.i(TAG, "No information available.");
        return;
        }

    json.put_EmitCompact(false);
    Log.i(TAG, json.emit());

    // Here's an example of the information about the signature:
    // {
    //   "pkcs7": {
    //     "verify": {
    //       "certs": [
    //         {
    //           "issuerCN": "Xyz EU Qualified Certificates CA G1",
    //           "serial": "99A28A51AC389999"
    //         }
    //       ],
    //       "useConstructedOctets": true,
    //       "digestAlgorithms": [
    //         "sha256"
    //       ],
    //       "signerInfo": [
    //         {
    //           "cert": {
    //             "subjectKeyIdentifier": "5VM4x8AWnXf07yzbXuLtbb0U3yY=",
    //             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
    //             "digestAlgName": "SHA256"
    //           },
    //           "signingAlgOid": "1.2.840.113549.1.1.11",
    //           "signingAlgName": "RSA-SHA256-PKCSV-1_5",
    //           "authAttr": {
    //             "1.2.840.113549.1.9.3": {
    //               "name": "contentType",
    //               "oid": "1.2.840.113549.1.7.1"
    //             },
    //             "1.2.840.113549.1.9.5": {
    //               "name": "signingTime",
    //               "utctime": "190901152340Z"
    //             },
    //             "1.2.840.113549.1.9.4": {
    //               "name": "messageDigest",
    //               "digest": "y+gd/zAQK33A//HInhaZba7w1fUJleV9AHbP1Ntx6U0="
    //             },
    //             "1.2.840.113549.1.9.16.2.47": {
    //               "name": "signingCertificateV2",
    //               "der": "MIH4MI..w4vv0="
    //             }
    //           }
    //         }
    //       ]
    //     }
    //   }
    // }

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    CkDtObj authAttrSigningTimeUtctime = new CkDtObj();
    String issuerCN;
    String serial;
    String strVal;
    String certSubjectKeyIdentifier;
    String certDigestAlgOid;
    String certDigestAlgName;
    String signingAlgOid;
    String signingAlgName;
    String authAttrContentTypeName;
    String authAttrContentTypeOid;
    String authAttrSigningTimeName;
    String authAttrMessageDigestName;
    String authAttrMessageDigestDigest;
    String authAttrSigningCertificateV2Name;
    String authAttrSigningCertificateV2Der;

    int i = 0;
    int count_i = json.SizeOfArray("pkcs7.verify.certs");
    while (i < count_i) {
        json.put_I(i);
        issuerCN = json.stringOf("pkcs7.verify.certs[i].issuerCN");
        serial = json.stringOf("pkcs7.verify.certs[i].serial");
        i = i + 1;
        }

    i = 0;
    count_i = json.SizeOfArray("pkcs7.verify.digestAlgorithms");
    while (i < count_i) {
        json.put_I(i);
        strVal = json.stringOf("pkcs7.verify.digestAlgorithms[i]");
        i = i + 1;
        }

    i = 0;
    count_i = json.SizeOfArray("pkcs7.verify.signerInfo");
    while (i < count_i) {
        json.put_I(i);
        certSubjectKeyIdentifier = json.stringOf("pkcs7.verify.signerInfo[i].cert.subjectKeyIdentifier");
        certDigestAlgOid = json.stringOf("pkcs7.verify.signerInfo[i].cert.digestAlgOid");
        certDigestAlgName = json.stringOf("pkcs7.verify.signerInfo[i].cert.digestAlgName");
        signingAlgOid = json.stringOf("pkcs7.verify.signerInfo[i].signingAlgOid");
        signingAlgName = json.stringOf("pkcs7.verify.signerInfo[i].signingAlgName");
        authAttrContentTypeName = json.stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".name");
        authAttrContentTypeOid = json.stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".oid");
        authAttrSigningTimeName = json.stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".name");
        json.DtOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".utctime",false,authAttrSigningTimeUtctime);
        authAttrMessageDigestName = json.stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".name");
        authAttrMessageDigestDigest = json.stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".digest");
        authAttrSigningCertificateV2Name = json.stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.16.2.47\".name");
        authAttrSigningCertificateV2Der = json.stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.16.2.47\".der");
        i = i + 1;
        }


  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}