CkPython

Create a CAdES-T Signature

See more CAdES Examples

Demonstrates how to create a signature with an external timestamp that certifies the time of signing. This requires an online TSA (Time Stamping Authority) service that is capable of producing RFC 3161 compliant timestamps.

Note: This example requires Chilkat v9.5.0.78 or greater.

CkPython

import sys
import chilkat

success = False

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

crypt = chilkat.CkCrypt2()

# This example will use a certificate + private key from a .pfx/.p12 file.
# On Windows systems, it is also possible to use certs on smartcards/usb tokens or certs pre-installed in the Windows registry.
cert = chilkat.CkCert()

pfxPath = "qa_data/pfx/myCertAndKey.p12"
pfxPassword = "test123"

success = cert.LoadPfxFile(pfxPath,pfxPassword)
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())

inFile = "qa_data/json/sample.json"
outFile = "qa_output/sample_cades_t.p7m"

# This creates the CAdES-T signature.  During the signature creation, it
# communicates with the TSA to get a timestampToken.
success = crypt.CreateP7M(inFile,outFile)
if (success != True):
    print(crypt.lastErrorText())
    sys.exit()

print("Success.")