Delphi DLL

P7S - Access Signature Information (date/time, certificate used, etc.)

See more Digital Signatures Examples

Examine a PKCS7 signature (.p7s) and get information about it. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, CkDateTime, BinData, JsonObject, Crypt2;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
bd: HCkBinData;
crypt: HCkCrypt2;
json: HCkJsonObject;
i: Integer;
count_i: Integer;
strVal: PWideChar;
certSerialNumber: PWideChar;
certIssuerCN: PWideChar;
certIssuerDN: PWideChar;
certDigestAlgOid: PWideChar;
certDigestAlgName: PWideChar;
contentType: PWideChar;
signingTime: PWideChar;
messageDigest: PWideChar;
signingAlgOid: PWideChar;
signerDigest: PWideChar;
dt: HCkDateTime;

begin
success := False;

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

// First load the .p7s file into a BinData object..
bd := CkBinData_Create();
success := CkBinData_LoadFile(bd,'qa_data/p7s/sample.p7s');
if (success <> True) then
  begin
    Memo1.Lines.Add('Failed to load .p7s file.');
    Exit;
  end;

crypt := CkCrypt2_Create();

// Assuming this is a signature that contains the original data that was signed..
success := CkCrypt2_OpaqueVerifyBd(crypt,bd);
if (success = False) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

// Examine the last JSON data after signature verification..
json := CkJsonObject_Create();
CkCrypt2_GetLastJsonData(crypt,json);

CkJsonObject_putEmitCompact(json,False);
Memo1.Lines.Add(CkJsonObject__emit(json));

// Sample output...
// Go to http://tools.chilkat.io/jsonParse.cshtml
// and paste the JSON into the online form to generate JSON parsing code.

// {
//   "pkcs7": {
//     "verify": {
//       "digestAlgorithms": [
//         "sha256"
//       ],
//       "signerInfo": [
//         {
//           "cert": {
//             "serialNumber": "AAC5FC48C0FD8FBB",
//             "issuerCN": "AC ABCDEF RFB v5",
//             "issuerDN": "",
//             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
//             "digestAlgName": "SHA-256"
//           },
//           "contentType": "1.2.840.113549.1.7.1",
//           "signingTime": "180607195054Z",
//           "messageDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8=",
//           "signingAlgOid": "1.2.840.113549.1.1.11",
//           "signerDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8="
//         },
//         {
//           "cert": {
//             "serialNumber": "324FB38ABD59723F",
//             "issuerCN": "AC ABCDEF RFB v5",
//             "issuerDN": "",
//             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
//             "digestAlgName": "SHA-256"
//           },
//           "contentType": "1.2.840.113549.1.7.1",
//           "signingTime": "180608182517Z",
//           "messageDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8=",
//           "signingAlgOid": "1.2.840.113549.1.1.11",
//           "signerDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8="
//         }
//       ]
//     }
//   }
// }
// 

dt := CkDateTime_Create();

i := 0;
count_i := CkJsonObject_SizeOfArray(json,'pkcs7.verify.digestAlgorithms');
while i < count_i do
  begin
    CkJsonObject_putI(json,i);
    strVal := CkJsonObject__stringOf(json,'pkcs7.verify.digestAlgorithms[i]');
    i := i + 1;
  end;

i := 0;
count_i := CkJsonObject_SizeOfArray(json,'pkcs7.verify.signerInfo');
while i < count_i do
  begin
    CkJsonObject_putI(json,i);
    certSerialNumber := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].cert.serialNumber');
    certIssuerCN := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].cert.issuerCN');
    certIssuerDN := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].cert.issuerDN');
    certDigestAlgOid := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].cert.digestAlgOid');
    certDigestAlgName := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].cert.digestAlgName');
    contentType := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].contentType');
    signingTime := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].signingTime');

    // The signingTime isin UTCTime format.
    // UTCTime values take the form of either "YYMMDDhhmm[ss]Z" or "YYMMDDhhmm[ss](+|-)hhmm"
    // Starting in Chilkat v9.5.0.77, the SetFromTimestamp method auto-recognizes the UTCTime format and parses it correctly.
    success := CkDateTime_SetFromTimestamp(dt,signingTime);
    // To get the signingTime in other date/time formats, look at the online reference documentation for CkDateTime.
    // There are numerous methods such as GetAsDateTime, GetAsIso8601, GetAsUnixTime, GetAsRfc822, etc.

    messageDigest := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].messageDigest');
    signingAlgOid := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].signingAlgOid');
    signerDigest := CkJsonObject__stringOf(json,'pkcs7.verify.signerInfo[i].signerDigest');
    i := i + 1;
  end;

// println crypt.LastErrorText;
Memo1.Lines.Add('Success.');

CkBinData_Dispose(bd);
CkCrypt2_Dispose(crypt);
CkJsonObject_Dispose(json);
CkDateTime_Dispose(dt);

end;