C#

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

See more Digital Signatures Examples

Examine a PKCS7 signature (.p7s) and get information about it. C#

bool 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..
Chilkat.BinData bd = new Chilkat.BinData();
success = bd.LoadFile("qa_data/p7s/sample.p7s");
if (success != true) {
    Debug.WriteLine("Failed to load .p7s file.");
    return;
}

Chilkat.Crypt2 crypt = new Chilkat.Crypt2();

// Assuming this is a signature that contains the original data that was signed..
success = crypt.OpaqueVerifyBd(bd);
if (success == false) {
    Debug.WriteLine(crypt.LastErrorText);
    return;
}

// Examine the last JSON data after signature verification..
Chilkat.JsonObject json = new Chilkat.JsonObject();
crypt.GetLastJsonData(json);

json.EmitCompact = false;
Debug.WriteLine(json.Emit());

// 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="
//         }
//       ]
//     }
//   }
// }
// 

int i;
int count_i;
string strVal;
string certSerialNumber;
string certIssuerCN;
string certIssuerDN;
string certDigestAlgOid;
string certDigestAlgName;
string contentType;
string signingTime;
string messageDigest;
string signingAlgOid;
string signerDigest;
Chilkat.CkDateTime dt = new Chilkat.CkDateTime();

i = 0;
count_i = json.SizeOfArray("pkcs7.verify.digestAlgorithms");
while (i < count_i) {
    json.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.I = i;
    certSerialNumber = json.StringOf("pkcs7.verify.signerInfo[i].cert.serialNumber");
    certIssuerCN = json.StringOf("pkcs7.verify.signerInfo[i].cert.issuerCN");
    certIssuerDN = json.StringOf("pkcs7.verify.signerInfo[i].cert.issuerDN");
    certDigestAlgOid = json.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgOid");
    certDigestAlgName = json.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgName");
    contentType = json.StringOf("pkcs7.verify.signerInfo[i].contentType");
    signingTime = json.StringOf("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 = dt.SetFromTimestamp(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 = json.StringOf("pkcs7.verify.signerInfo[i].messageDigest");
    signingAlgOid = json.StringOf("pkcs7.verify.signerInfo[i].signingAlgOid");
    signerDigest = json.StringOf("pkcs7.verify.signerInfo[i].signerDigest");
    i = i + 1;
}

// println crypt.LastErrorText;
Debug.WriteLine("Success.");