(CkPython) Renew a DigiCert Certificate from an EST-enabled profile

Demonstrates how to renew a certificate from an EST-enabled profile in DigiCert​​®​​ Trust Lifecycle Manager. (The certificate must be within the renewal window configured in the certificate profile. The CSR must have same Subject DN values as the original certificate.)

Chilkat Python Downloads install with pip pip3 install chilkat or download... Python Module for Windows, MacOS, Linux, Alpine Linux, Solaris

import sys
import chilkat

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

# The example below duplicates the following OpenSSL commands:
# 
# # Name of certificate as argument 1
# 
# # Make new key
# openssl ecparam -name prime256v1 -genkey -noout -out ${1}.key.pem
# 
# # Make csr
# openssl req -new -sha256 -key ${1}.key.pem -out ${1}.p10.csr -subj "/CN=${1}"
# 
# # Request new cert
# curl -v --cacert data/ca.pem --cert data/${1}.pem --key data/${1}.key.pem 
#     --data-binary @${1}.p10.csr -o ${1}.p7.b64 -H "Content-Type: application/pkcs10" https://clientauth.demo.one.digicert.com/.well-known/est/IOT/simplereenroll
# 
# # Convert to PEM
# openssl base64 -d -in ${1}.p7.b64 | openssl pkcs7 -inform DER -outform PEM -print_certs -out ${1}.pem

# ------------------------------------------------------------------------------------------------------------------

# Create a Fortuna PRNG and seed it with system entropy.
# This will be our source of random data for generating the ECC private key.
fortuna = chilkat.CkPrng()
entropy = fortuna.getEntropy(32,"base64")
success = fortuna.AddEntropy(entropy,"base64")

ec = chilkat.CkEcc()

# Generate a random EC private key on the prime256v1 curve.
# privKey is a CkPrivateKey
privKey = ec.GenEccKey("prime256v1",fortuna)
if (ec.get_LastMethodSuccess() != True):
    print(ec.lastErrorText())
    sys.exit()

# Create the CSR object and set properties.
csr = chilkat.CkCsr()

# Specify your CN
csr.put_CommonName("mysubdomain.mydomain.com")

# Create the CSR using the private key.
bdCsr = chilkat.CkBinData()
success = csr.GenCsrBd(privKey,bdCsr)
if (success == False):
    print(csr.lastErrorText())

    sys.exit()

# Save the private key and CSR to files.
privKey.SavePkcs8EncryptedPemFile("password","c:/temp/qa_output/ec_privkey.pem")

bdCsr.WriteFile("c:/temp/qa_output/csr.pem")

# ----------------------------------------------------------------------
# Now do the CURL request to POST the CSR and get the new certificate.

http = chilkat.CkHttp()

tlsClientCert = chilkat.CkCert()
success = tlsClientCert.LoadFromFile("data/myTlsClientCert.pem")
if (success == False):
    print(tlsClientCert.lastErrorText())
    sys.exit()

bdTlsClientCertPrivKey = chilkat.CkBinData()
success = bdTlsClientCertPrivKey.LoadFile("data/myTlsClientCert.key.pem")
if (success == False):
    print("Failed to load data/myTlsClientCert.key.pem")
    sys.exit()

tlsClientCertPrivKey = chilkat.CkPrivateKey()
success = tlsClientCertPrivKey.LoadAnyFormat(bdTlsClientCertPrivKey,"")
if (success == False):
    print(tlsClientCertPrivKey.lastErrorText())
    sys.exit()

success = tlsClientCert.SetPrivateKey(tlsClientCertPrivKey)
if (success == False):
    print(tlsClientCert.lastErrorText())
    sys.exit()

http.SetSslClientCert(tlsClientCert)

http.put_RequireSslCertVerify(True)

# The body of the HTTP request contains the binary CSR.
# resp is a CkHttpResponse
resp = http.PBinaryBd("POST","https://clientauth.demo.one.digicert.com/.well-known/est/IOT/simplereenroll",bdCsr,"application/pkcs10",False,False)
if (http.get_LastMethodSuccess() == False):
    print(http.lastErrorText())
    sys.exit()

if (resp.get_StatusCode() != 200):
    print("response status code = " + str(resp.get_StatusCode()))
    print(resp.bodyStr())
    print("Failed")

    sys.exit()

# The response is the Base64 DER of the new certificate.
myNewCert = chilkat.CkCert()
success = myNewCert.LoadFromBase64(resp.bodyStr())
if (success == False):
    print(myNewCert.lastErrorText())
    print("Cert data = " + resp.bodyStr())
    print("Failed.")

    sys.exit()

success = myNewCert.SaveToFile("c:/temp/qa_output/myNewCert.cer")
if (success == False):
    print(myNewCert.lastErrorText())
    print("Failed.")
    sys.exit()

print("Success.")