(VB.NET) 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.)

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' 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.
Dim fortuna As New Chilkat.Prng
Dim entropy As String = fortuna.GetEntropy(32,"base64")
Dim success As Boolean = fortuna.AddEntropy(entropy,"base64")


Dim ec As New Chilkat.Ecc

' Generate a random EC private key on the prime256v1 curve.
Dim privKey As Chilkat.PrivateKey = ec.GenEccKey("prime256v1",fortuna)
If (ec.LastMethodSuccess <> True) Then
    Debug.WriteLine(ec.LastErrorText)
    Exit Sub
End If



' Create the CSR object and set properties.
Dim csr As New Chilkat.Csr

' Specify your CN
csr.CommonName = "mysubdomain.mydomain.com"

' Create the CSR using the private key.
Dim bdCsr As New Chilkat.BinData
success = csr.GenCsrBd(privKey,bdCsr)
If (success = False) Then
    Debug.WriteLine(csr.LastErrorText)

    Exit Sub
End If


' 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.

Dim http As New Chilkat.Http

Dim tlsClientCert As New Chilkat.Cert
success = tlsClientCert.LoadFromFile("data/myTlsClientCert.pem")
If (success = False) Then
    Debug.WriteLine(tlsClientCert.LastErrorText)
    Exit Sub
End If


Dim bdTlsClientCertPrivKey As New Chilkat.BinData
success = bdTlsClientCertPrivKey.LoadFile("data/myTlsClientCert.key.pem")
If (success = False) Then
    Debug.WriteLine("Failed to load data/myTlsClientCert.key.pem")
    Exit Sub
End If


Dim tlsClientCertPrivKey As New Chilkat.PrivateKey
success = tlsClientCertPrivKey.LoadAnyFormat(bdTlsClientCertPrivKey,"")
If (success = False) Then
    Debug.WriteLine(tlsClientCertPrivKey.LastErrorText)
    Exit Sub
End If


success = tlsClientCert.SetPrivateKey(tlsClientCertPrivKey)
If (success = False) Then
    Debug.WriteLine(tlsClientCert.LastErrorText)
    Exit Sub
End If


http.SetSslClientCert(tlsClientCert)

http.RequireSslCertVerify = True


' The body of the HTTP request contains the binary CSR.
Dim resp As Chilkat.HttpResponse = http.PBinaryBd("POST","https://clientauth.demo.one.digicert.com/.well-known/est/IOT/simplereenroll",bdCsr,"application/pkcs10",False,False)
If (http.LastMethodSuccess = False) Then
    Debug.WriteLine(http.LastErrorText)
    Exit Sub
End If



If (resp.StatusCode <> 200) Then
    Debug.WriteLine("response status code = " & resp.StatusCode)
    Debug.WriteLine(resp.BodyStr)
    Debug.WriteLine("Failed")

    Exit Sub
End If


' The response is the Base64 DER of the new certificate.
Dim myNewCert As New Chilkat.Cert
success = myNewCert.LoadFromBase64(resp.BodyStr)
If (success = False) Then
    Debug.WriteLine(myNewCert.LastErrorText)
    Debug.WriteLine("Cert data = " & resp.BodyStr)
    Debug.WriteLine("Failed.")

    Exit Sub
End If



success = myNewCert.SaveToFile("c:/temp/qa_output/myNewCert.cer")
If (success = False) Then
    Debug.WriteLine(myNewCert.LastErrorText)
    Debug.WriteLine("Failed.")
    Exit Sub
End If


Debug.WriteLine("Success.")