CkPython

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. CkPython

import sys
import chilkat

success = False

crypt = chilkat.CkCrypt2()

cert = chilkat.CkCert()
cert.put_SmartCardPin("123456")
success = cert.LoadFromSmartcard("")
if (success != True):
    print(cert.lastErrorText())
    sys.exit()

success = crypt.SetSigningCert(cert)

# Use SHA-256 rather than the default of SHA-1
crypt.put_HashAlgorithm("sha256")

# Create JSON that tells Chilkat what signing attributes to include:
attrs = chilkat.CkJsonObject()
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.put_SigningAttributes(attrs.emit())

strToSign = "Hello World!"

bd = chilkat.CkBinData()
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.
http = chilkat.CkHttp()
# This can be a domain name, hostname, or IP address.
http.put_ProxyDomain("172.16.16.56")
http.put_ProxyPort(808)
http.put_ProxyLogin("myProxyLogin")
http.put_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):
    print(crypt.lastErrorText())
    sys.exit()

# Get the signature in base64 format:
print(bd.getEncoded("base64_mime"))

print("Success.")