C
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.Chilkat C Downloads
#include <C_CkCrypt2.h>
#include <C_CkCert.h>
#include <C_CkJsonObject.h>
#include <C_CkBinData.h>
#include <C_CkHttp.h>
void ChilkatSample(void)
{
BOOL success;
HCkCrypt2 crypt;
HCkCert cert;
HCkJsonObject attrs;
const char *strToSign;
HCkBinData bd;
HCkHttp http;
success = FALSE;
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);
}