(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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#include <C_CkCrypt2.h>
#include <C_CkCert.h>
#include <C_CkJsonObject.h>
#include <C_CkBinData.h>
#include <C_CkHttp.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    HCkCert cert;
    BOOL success;
    HCkJsonObject attrs;
    const char *strToSign;
    HCkBinData bd;
    HCkHttp http;

    crypt = CkCrypt2_Create();

    cert = CkCert_Create();
    CkCert_putSmartCardPin(cert,"123456");
    success = CkCert_LoadFromSmartcard(cert,"");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkCrypt2_Dispose(crypt);
        CkCert_Dispose(cert);
        return;
    }

    success = CkCrypt2_SetSigningCert(crypt,cert);

    // Use SHA-256 rather than the default of SHA-1
    CkCrypt2_putHashAlgorithm(crypt,"sha256");

    // Create JSON that tells Chilkat what signing attributes to include:
    attrs = CkJsonObject_Create();
    CkJsonObject_UpdateBool(attrs,"contentType",TRUE);
    CkJsonObject_UpdateBool(attrs,"signingTime",TRUE);
    CkJsonObject_UpdateBool(attrs,"messageDigest",TRUE);
    CkJsonObject_UpdateBool(attrs,"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.
    CkJsonObject_UpdateBool(attrs,"timestampToken.enabled",TRUE);
    CkJsonObject_UpdateString(attrs,"timestampToken.tsaUrl","https://freetsa.org/tsr");
    CkJsonObject_UpdateBool(attrs,"timestampToken.addNonce",FALSE);
    CkJsonObject_UpdateBool(attrs,"timestampToken.requestTsaCert",TRUE);
    CkJsonObject_UpdateString(attrs,"timestampToken.hashAlg","sha256");

    CkCrypt2_putSigningAttributes(crypt,CkJsonObject_emit(attrs));

    strToSign = "Hello World!";

    bd = CkBinData_Create();
    CkBinData_AppendString(bd,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.
    http = CkHttp_Create();
    // This can be a domain name, hostname, or IP address.
    CkHttp_putProxyDomain(http,"172.16.16.56");
    CkHttp_putProxyPort(http,808);
    CkHttp_putProxyLogin(http,"myProxyLogin");
    CkHttp_putProxyPassword(http,"myProxyPassword");
    CkCrypt2_SetTsaHttpObj(crypt,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 = CkCrypt2_OpaqueSignBd(crypt,bd);
    if (success != TRUE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCrypt2_Dispose(crypt);
        CkCert_Dispose(cert);
        CkJsonObject_Dispose(attrs);
        CkBinData_Dispose(bd);
        CkHttp_Dispose(http);
        return;
    }

    // Get the signature in base64 format:
    printf("%s\n",CkBinData_getEncoded(bd,"base64_mime"));

    printf("Success.\n");


    CkCrypt2_Dispose(crypt);
    CkCert_Dispose(cert);
    CkJsonObject_Dispose(attrs);
    CkBinData_Dispose(bd);
    CkHttp_Dispose(http);

    }