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CkPython

PKCS7 Sign Text using RSA 2048, SHA256, Base64 Output

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Demonstrates how to sign text using 2048-bit RSA with SHA256, producing PKCS#7 output in Base64. The certificate w/ private key used for signing is loaded from a .p12/.pfx file.

Chilkat CkPython Downloads

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.

cert = chilkat.CkCert()

# Load the cert and private key.  Whatever the private key happens to be,
# such as RSA or ECC, then Chilkat will use it.  If the private key is 
# a 2048-bit RSA key, then that's what will be used..
success = cert.LoadPfxFile("qa_data/pfx/myCertAndKey.p12","password")
if (success != True):
    print(cert.lastErrorText())
    sys.exit()

crypt = chilkat.CkCrypt2()

success = crypt.SetSigningCert(cert)
if (success != True):
    print(crypt.lastErrorText())
    sys.exit()

# Use SHA-256
crypt.put_HashAlgorithm("sha256")

# Hash the utf-8 byte representation of the string
crypt.put_Charset("utf-8")

# Return the result in base64
crypt.put_EncodingMode("base64")

# Sign some text..
textToSign = "This is the text to be hashed and signed."
sigBase64 = crypt.opaqueSignStringENC(textToSign)
if (crypt.get_LastMethodSuccess() != True):
    print(crypt.lastErrorText())
    sys.exit()

print(sigBase64)

# The result:
# MIIS2wYJKoZIhvcNAQc ... zGeeY4Oxg==