(C#) Sign String to create a CAdES-T Signature, using HTTP Proxy to Access Timestamp Server

This example will sign a string to create a CAdEST-T signature. It will use an HTTP proxy to access the timestamp server.

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

Chilkat.Cert cert = new Chilkat.Cert();
cert.SmartCardPin = "123456";
bool success = cert.LoadFromSmartcard("");
if (success != true) {
    Debug.WriteLine(cert.LastErrorText);
    return;
}

success = crypt.SetSigningCert(cert);

// Use SHA-256 rather than the default of SHA-1
crypt.HashAlgorithm = "sha256";

// Create JSON that tells Chilkat what signing attributes to include:
Chilkat.JsonObject attrs = new Chilkat.JsonObject();
attrs.UpdateBool("contentType",true);
attrs.UpdateBool("signingTime",true);
attrs.UpdateBool("messageDigest",true);
attrs.UpdateBool("signingCertificateV2",true);

// A CAdES-T signature is one that includes a timestampToken created by an online TSA (time stamping authority).
// We must include the TSA's URL, as well as a few options to indicate what is desired.
// Except for the TSA URL, the options shown here are typically what you would need.
attrs.UpdateBool("timestampToken.enabled",true);
attrs.UpdateString("timestampToken.tsaUrl","https://freetsa.org/tsr");
attrs.UpdateBool("timestampToken.addNonce",false);
attrs.UpdateBool("timestampToken.requestTsaCert",true);
attrs.UpdateString("timestampToken.hashAlg","sha256");

crypt.SigningAttributes = attrs.Emit();

string strToSign = "Hello World!";

Chilkat.BinData bd = new Chilkat.BinData();
bd.AppendString(strToSign,"utf-8");

// -------------------------------------------------------------------------
// The purpose of this example is to show how an HTTP object with custom
// settings can be used to access the Internet when signing.
// Access to the Internet is needed to communicate with the timestamp server.
Chilkat.Http http = new Chilkat.Http();
// This can be a domain name, hostname, or IP address.
http.ProxyDomain = "172.16.16.56";
http.ProxyPort = 808;
http.ProxyLogin = "myProxyLogin";
http.ProxyPassword = "myProxyPassword";
crypt.SetTsaHttpObj(http);
// -------------------------------------------------------------------------

// This creates the CAdES-T signature.  During the signature creation, it
// communicates with the TSA to get a timestampToken.
// The contents of bd are signed and replaced with the CAdES-T signature (which embeds the original content).
success = crypt.OpaqueSignBd(bd);
if (success != true) {
    Debug.WriteLine(crypt.LastErrorText);
    return;
}

// Get the signature in base64 format:
Debug.WriteLine(bd.GetEncoded("base64_mime"));

Debug.WriteLine("Success.");